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NACE MR0175- CRA
Written Exam
My Reading 2b QA 51100
2017 Nov 24
th
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Oil Exploration Production
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Oil Exploration Production
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Oil Exploration Production
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Oil Exploration Production
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闭门练功
slide 8: 闭门练功
Charlie Chong/ Fion Zhang
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闭门练功
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闭门练功
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闭
门
练
功
slide 12: NACE MR0175 Written Exam
Charlie Chong/ Fion Zhang
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ISO 15156-1:2009E
9 Report of the method of selection or qualification
Materials selected or qualified in accordance with this part of ISO 15156 shall
have the method of selection documented by reporting item a from the
following list together with one other item b c or d:
https://oilandgascorrosion.com/faqs/
slide 15: Charlie Chong/ Fion Zhang
51. Is there a NACE office available in Italy or in other European
countries
Question:
Is a NACE office available in Italy or in other European countries
All inquiries should be transmitted to the ISO Maintenance NACE
Headquarters in Houston Texas Maintenance.Panelnace.org. The
Maintenance Panel has an international membership. Details of its current
membership can be obtained from the above address.
This question is in relation to NACE MR0175/ISO 15156
Reference: ISO 15156 Maintenance Panel Inquiry 2003-26 Q5
https://oilandgascorrosion.com/faqs/
slide 16: Charlie Chong/ Fion Zhang
52. Is ISO 9001/9002 required to supply NACE MR0175 equipment and
material
Question:
Some buyers in the U.S. are requesting equipment to ISO 15156 and then saying that
the supplying company has to be ISO registered i.e. has ISO 9002 in place quality
standard. As far as I know these are unrelated issues a supplier to ISO 15156 does
not have to be ISO 9002 registered. Can the Maintenance Panel confirm that ISO
9002 is not a requirement for supply to ISO 15156 Is there an equivalent U.S.
standard to ISO 9002
Answer:
ISO 9002 is NOT referenced in any of the ISO 15156 parts. That means ISO 9002 is
not necessary to comply with ISO 15156.
If ISO 9002 is part of a contract between two business parties ISO 9002 becomes a
requirement based on the contract not based on ISO 15156.
In addition ISO 9002 has been replaced by ISO 9001: Quality management systems--
Requirements.
There are no widely accepted American equivalents to either ISO 9002 or ISO 9001.
This question is in relation to NACE MR0175/ISO 15156
Reference: ISO 15156 Maintenance Panel Inquiry 2009-25
https://oilandgascorrosion.com/faqs/
slide 17: Charlie Chong/ Fion Zhang
53. Crude oil storage does it have to comply with NACE MR0175
Question:
Crude oil storage and handling facilities operating at a total absolute pressure
below 0.45 MPa. My understanding of the above paragraph is that it includes
only dead oils with no gas in equilibrium. If any gas is in equilibrium with a
crude operating less than 0.45 MPa which contains H2S more than 0.3kPa
in the gas phase the whole system is considered as sour. I need your
advice for my understanding if correct or not
Answer:
Crude oil storage and handling facilities means that it is dead oil and
H2S/CO2 have been removed. The very low residual amount is considered
negligible. This is the reason why these facilities are permitted exclusions
from the standard. However it is up to the user to check that these
statements are true for the considered facilities.
This question is in relation to NACE MR0175/ISO 15156
Reference: ISO 15156 Maintenance Panel Inquiry 2009-14
https://oilandgascorrosion.com/faqs/
slide 18: Charlie Chong/ Fion Zhang
Remarks:
Crude oil storage and handling
facilities means that it is dead oil and
H
2
S/CO
2
have been removed.
The very low residual amount is
considered negligible.
The P
H2S
is thus believe to be
0.3kPa / 0.05 psi
https://oilandgascorrosion.com/faqs/
slide 19: Charlie Chong/ Fion Zhang
Crude Oil Storage- Exclusion item
https://oilandgascorrosion.com/faqs/
slide 20: Charlie Chong/ Fion Zhang
Crude Oil Storage Handling- Exclusion item
https://oilandgascorrosion.com/faqs/
slide 21: Charlie Chong/ Fion Zhang
Crude Oil Storage Handling- Exclusion item
https://oilandgascorrosion.com/faqs/
slide 22: Charlie Chong/ Fion Zhang
ISO 15156-3:2015E
Table 1 — List of equipment
https://oilandgascorrosion.com/faqs/
ISO 15156 is applicable to materials
used for the
following equipment
Permitted exclusions
Flow-lines gathering lines field facilities
and field processing plants
Crude oil storage and handling facilities
operating at
a total absolute pressure below 045 MPa
65 psi
Water-handling equipment Water-handling facilities operating at a
total absolute
pressure below 045 MPa 65 psi
Water injection and water disposal
equipment
slide 23: Charlie Chong/ Fion Zhang
Permitted exclusions
Crude oil storage and handling facilities operating at
a total absolute pressure below 045 MPa 65 psi
https://oilandgascorrosion.com/faqs/
slide 24: Charlie Chong/ Fion Zhang https://oilandgascorrosion.com/faqs/
Permitted exclusions
Crude oil storage and handling facilities operating at
a total absolute pressure below 045 MPa 65 psi
slide 25: Charlie Chong/ Fion Zhang https://oilandgascorrosion.com/faqs/
Permitted exclusions
Crude oil storage and handling facilities operating at
a total absolute pressure below 045 MPa 65 psi
slide 26: Charlie Chong/ Fion Zhang
ISO 15156 is applicable to materials used for the
following equipment –
Flow-lines gathering lines field facilities and field processing plants
Transportation pipelines for liquids gases and multi-phase fluids
https://oilandgascorrosion.com/faqs/
slide 27: Charlie Chong/ Fion Zhang https://oilandgascorrosion.com/faqs/
ISO 15156 is applicable to materials used for the
following equipment –
Flow-lines gathering lines field facilities and field processing plants
Transportation pipelines for liquids gases and multi-phase fluids
slide 28: Charlie Chong/ Fion Zhang
54. Who is responsible for certification of materials and equipment to
NACE MR0175 The manufacturer or the user
Question:
Is it the intent of NACE MR0175/ISO 15156-2 that material manufacturers state on the
Material Test Certificates that material conforms to the NACE standard even though
no operating criteria are known
Answer:
Certification requirements are outside the scope of the standard and there are no
stipulations concerning certification in NACE MR0175/ISO 15156.
The compliance with the NACE/ISO standard of a material for use in H2S-containing
environments in oil and gas can only be assessed for the material in its final product
form and this may differ metallurgically from that of the material supplied by the
materials manufacturer. In addition compliance with the standard also depends on the
cracking mechanisms that have to be considered.
NACE MR0175/ISO 15156-2 Clause 9 Annex E Informative and NACE
MR0175/ISO 15156-3 7.2 Annex C Informative make some suggestions on how
materials manufacturers and other suppliers might mark their materials to indicate the
evaluation testing that they have carried out.
This question is in relation to NACE MR0175/ISO 15156 / Certification and
Compliance
Reference: ISO 15156 Maintenance Panel Inquiry 2006-13.
https://oilandgascorrosion.com/faqs/
slide 29: Charlie Chong/ Fion Zhang
Certification requirements are outside the
scope of the standard and there are no
stipulations concerning certification in NACE
MR0175/ISO 15156.
The compliance with the NACE/ISO standard
of a material for use in H2S-containing
environments in oil and gas can only be
assessed for the material in its final product
form and this may differ metallurgically from
that of the material supplied by the materials
manufacturer.
https://oilandgascorrosion.com/faqs/
slide 30: Charlie Chong/ Fion Zhang
In addition compliance with the
standard also depends on the
cracking mechanisms that have
to be considered.
https://oilandgascorrosion.com/faqs/
slide 31: Charlie Chong/ Fion Zhang
Discussion on:
The compliance with the NACE/ISO standard of a material for use in
H2S-containing environments in oil and gas can only be assessed for
the material in its final product form and this may differ metallurgically
from that of the material supplied by the materials manufacturer.
https://oilandgascorrosion.com/faqs/
slide 32: Charlie Chong/ Fion Zhang
■ ωσμ∙Ωπ∆ ∇ º≠δ≤ηθφФρ|β≠Ɛ∠ ʋ λ α ρτ√ ≠≥ѵФε ≠≥ѵФ:
https://oilandgascorrosion.com/faqs/
Discussion on:
In addition compliance with the standard also depends on the cracking
mechanisms that have to be considered.
slide 33: Charlie Chong/ Fion Zhang
55. What is NACE MR0175 definition of a Corrosion Resistant Alloy
CRA
Question:
I need your help with the definition of CRAs in Part 3 of MR0175/ISO 15156.
The "corrosion-resistant alloys" is very general and does not specify whether
or not the definition includes the Fe-based alloys or not. More than that the
term CRA is used together with "other alloys" making it even more confusing.
Answer:
NACE MR0175/ISO 15156-1 Paragraph 3.6 contains a definition of
"corrosion-resistant alloy" CRA. It reads: "alloy intended to be resistant to
general and localized corrosion of oilfield environments that are corrosive to
carbon steel." This is taken from EFC 17.
"Other Alloys" are those not covered by the definitions of carbon steel or CRA.
For example copper is not considered resistant to general corrosion but is
considered in NACE MR0175/ISO 15156-3.
This question is in relation to NACE MR0175/ISO 15156-1 Clause 3
Reference: ISO 15156 Maintenance Panel Inquiry 2004-12
https://oilandgascorrosion.com/faqs/
slide 34: Charlie Chong/ Fion Zhang
56. Are metal rupture discs outside of the scope of NACE MR0175-ISO
15156
Question: Using NACE MR0175-ISO 15156-1 Clause 5 Paragraph 9 and
NACE Interpretation MP INQUIRY 2009-05 Part 1 as references. Based on
the fact that most metal rupture discs are plastically deformed during
manufacturing and all metal rupture discs plastically deform when they burst
are metal rupture discs outside of the scope of NACE MR0175-ISO 15156
Answer:
No. Permitted exclusions are listed in ISO 15156-1 Table 1. When ISO 15156
is specified components including rupture discs must comply with the
materials and conditions listed in the standard or qualified in accordance with
Annex B.
This question is in relation to NACE MR0175/ISO 15156-1 Clause 5
Reference: ISO 15156 Maintenance Panel Inquiry 2011-08
https://oilandgascorrosion.com/faqs/
slide 35: Charlie Chong/ Fion Zhang
57. NACE MR0175 and elastic or plastic design criteria
Question:
Unfortunately answer 2011-08 left my organization at a loss. This answer
does not address the fact that NACE MR0175-ISO 15156-1 Clause 5 states:
This part of ANSI/NACE MR0175/ISO 15156 applies to the qualification and
selection of materials for equipment designed and constructed using
conventional elastic design criteria. For designs using plastic criteria e.g.
stain-based and limit-states designs use of this part of ANSI/NACE
MR0175/ISO 15156 might not be appropriate and the equipment/material
supplier in conjunction with the equipment user shall assess the need for
other requirements. This response does not address the issue that rupture
discs plastically deform which is at the heart of and the basis of the previous
inquiry. Metal rupture discs are made 8 to order product that plastically
deform as part of the manufacturing process and will plastically deform when
they burst fail when exposed to an overpressure process condition.
https://oilandgascorrosion.com/faqs/
slide 36: Charlie Chong/ Fion Zhang
Answer:
"The Maintenance Panel for NACE MR0175/ISO 15156 has reviewed your
inquiry submitted May 4 2012. You asked for further clarification of the
answers to MP Inquiries 2009-05 and 2011-08.
Here is the Maintenance Panel’s response:
• The answer previously given has been confirmed to be correct by the
Maintenance Panel MP.
• The MP also confirms there is no conflict with the reply given for Inquiry
2009-05.
• Since the rupture disk is not a “Table A.1 exclusion” it must either meet the
material requirements in Annex A or be approved by the end user based on
laboratory testing or field history. Confirming compliance with the material
requirements in Annex A may be difficult for a rupture disk. However it may
be possible to demonstrate that the same raw material sheet with plastic
deformation equivalent to worst-case locations on the rupture disk have
metallurgical properties well within the material requirements in the standard.
https://oilandgascorrosion.com/faqs/
slide 37: Charlie Chong/ Fion Zhang
Additional comments from other MP members:
1. On the issue of plastic deformation during manufacturing:
-Whether the material is plastically deformed in fabrication is not the issue here.
-Plastic deformation during manufacturing is irrelevant to clause 5 paragraph 9.
2. On the issue of deformation during rupture:
-Plastic deformation occurs when they burst but then they’re intended to burst.
-The rupture disk functions within its elastic limit during the pressure-containing
bulk of its service life. They are not designed to operate after additional in situ
deformation i.e. no strain-based design. Plastic deformation on failure is
incidental to the function.
-The purpose of the wording in Part 1 Section 5 is to cover design criteria
where the material is expected to function beyond the elastic limit in service
without failing strain-based designs for pipelines being a prime example.
Bursting disks do not fall into this category either being plastically deformed
cold worked prior to service or suffering from plastic deformation incidental to
failure albeit failure is part of the function of the bursting disc in cases of over
pressurization in service."
This question is in relation to NACE MR0175/ISO 15156-1 Clause 5
https://oilandgascorrosion.com/faqs/
slide 38: Charlie Chong/ Fion Zhang
58. How can used and old equipment be certified to NACE MR0175
Question:
My customer has some swab tanks that were manufactured in 1953 they are made of rolled 1/2-
inch plate A283C the tank is 84 in. in diameter and is rated for 100-psi service. The question is
given the following conditions does this tank meet NACE MR0175 According to Section A2.1.6
the requirement that all rolled or deformed material must be stress relieved and have a hardness
of 22 HRC max. The problem is we cannot or have no documentation as it relates to the heat
treat of the plate post welding. yet when tested the material meets the A283C requirements and
the hardness are in the 120-127 HB. Ultrasonic testing as part of a corrosion survey on the tank
was performed and all was in order. Engineering approval was granted on the status of the
vessel as a pressure vessel under the ABSA Alberta Boilers Safety Association. This tank is 52
years old is in excellent condition and the customer wants to have more current documents on
the tank as it relates to its status as an ABSA pressure vessel and its NACE MR0175. With all
this information can a determination be made that this material in its current state is suitable as a
material that qualifies as a NACE MR0175/ISO 15156-compliant material Using the long life
performance and the mechanical data gathered can this determination be made If so can
these criteria be used to establish a basis for performing future work on this exact style of tank
Answer:
The ISO 15156 Maintenance Panel cannot advise on the suitability of this tank for use in sour
service. It is the responsibility of the equipment user to assess the suitability of the material and
to ensure compliance with NACE MR0175 / ISO 15156.
https://oilandgascorrosion.com/faqs/
slide 39: Charlie Chong/ Fion Zhang
Answer:
The ISO 15156 Maintenance Panel
cannot advise on the suitability of this
tank for use in sour service. It is the
responsibility of the equipment user to
assess the suitability of the material
and to ensure compliance with NACE
MR0175 / ISO 15156.
https://oilandgascorrosion.com/faqs/
slide 40: Charlie Chong/ Fion Zhang
MP do not advice on the
suitability of equipment
The User responsibility to
assess the suitability of
equipment
https://oilandgascorrosion.com/faqs/
slide 41: Charlie Chong/ Fion Zhang
Discussion on:
How the user assess the suitability of equipment in the intended
environment What are the basis of acceptance
https://oilandgascorrosion.com/faqs/
slide 42: Charlie Chong/ Fion Zhang
59. What are the NACE MR0175 requirements for C95800 C95400
C95500 and C63200
Question:
We are using the following materials for manufacturing of valve components. In
reference to the clause A.12.1 of NACE MR0175/ISO 15156-3:2003 no any special
requirements are specified to these materials for use in SOUR environment. We wish
to know what shall be the chemical physical hardness properties and heat treatment
requirements for using these materials in SOUR service environment. Valve
Components: Body – ASTM B148 UNS C95800 C95400 C95500. Stem – ASTM
B150 UNS C63200. Ball – ASTM B148 UNS C95800.
Answer:
For these materials there are no 15156 restrictions on chemistry hardness or heat
treatment. However note that these materials can undergo severe weight loss
corrosion. They may also be susceptible hydrogen stress cracking when galvanically
coupled to steel. It is up to the user to decide if qualification of these materials is
necessary in the applicable sour service environment. § 8 of NACE MR0175/ISO
15156 Part 1 indicates how these materials can be qualified.
This question is in relation to NACE MR0175/ISO 15156-1 Clause 8
Reference: ISO 15156 Maintenance Panel Inquiry 2009-12
https://oilandgascorrosion.com/faqs/
slide 43: Charlie Chong/ Fion Zhang
ASTM B150 / B150M - 122017
Standard Specification for Aluminum Bronze Rod Bar and Shapes
A.12.1 Copper-based alloys
Copper-based alloys have been used without restriction on temperature
pH2S Cl− or in situ pH in production environments.
NOTE 1 Copper-based alloys can undergo accelerated mass loss corrosion
weight loss corrosion in sour oil field environments particularly if oxygen is
present.
NOTE 2 Some copper-based alloys have shown sensitivity to GHSC.
A.12.2 Aluminium-based alloys
These materials have been used without restriction on temperature pH2S
Cl− or in situ pH in production environments.
The user should be aware that mass loss corrosion weight loss corrosion of
aluminium-based alloys is strongly dependent on environmental pH.
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slide 44: Charlie Chong/ Fion Zhang
For Copper and Aluminum
materials
“ have been used without
restriction ”
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slide 45: Charlie Chong/ Fion Zhang
For Copper and Aluminum
materials
“ It is up to the user to decide
if qualification of these
materials is necessary ”
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slide 46: Charlie Chong/ Fion Zhang
60. Successful field service No documentation What does NACE
MR0175 require
Question:
When materials in an existing field are replaced what criteria should be used
Paragraph 8.2 of ISO 15156-1 provides some criteria for qualification but it is
not clear what approach should be used for materials that have been in use
with no problems but documentation does not exist.
Answer:
NACE MR0175/ISO 15156-1 Paragraphs 6.2 8.1 8.2 and 9.0 provide a
complete description of the documentation required for two years’ successful
field service. Documentation has always been required.
This question is in relation to NACE MR0175/ISO 15156-1 Clause 8.2
Reference: ISO 15156 Maintenance Panel Inquiry 2003-41
https://oilandgascorrosion.com/faqs/
slide 47: Charlie Chong/ Fion Zhang
ISO 15156-1:2009E
8 Qualification of materials for H2S service
8.1 Material description and documentation
The material being qualified shall be described and documented such that
those of its properties likely to affect performance in H2S-containing media
are defined. The tolerances or ranges of properties that can occur within the
material shall be described and documented.
Metallurgical properties known to affect performance in H2S-containing
environments include chemical composition method of manufacture product
form strength hardness amount of cold work heat-treatment condition and
microstructure.
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slide 48: Charlie Chong/ Fion Zhang
8.2 Qualification based upon field experience
A material may be qualified by documented field experience. The material
description shall meet the requirements of 8.1. The description of the service
conditions in which the experience has been gained shall meet the relevant
requirements of 6.1.
The duration of the documented field experience shall be at least two
years and should preferably involve a full examination of the equipment
following field use. The severity of intended service conditions shall not
exceed that of the field experience for which documented records are
available.
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slide 49: Charlie Chong/ Fion Zhang
6 Evaluation and definition of service conditions to enable material
selection
6.1 Before selecting or qualifying materials using Parts 2 and 3 of ISO 15156
the user of the equipment shall define evaluate and document the service
conditions to which materials can be exposed for each application. The
defined conditions shall include both intended exposures and unintended
exposures that can result from the failure of primary containment or protection
methods. Particular attention shall be paid to the quantification of those
factors known to affect the susceptibility of materials to cracking caused by
H2S.
Factors other than material properties known to affect the susceptibility of
metallic materials to cracking in H2S service include H2S partial pressure in
situ pH the concentration of dissolved chloride or other halide the presence
of elemental sulfur or other oxidant temperature galvanic effects mechanical
stress and time of exposure to contact with a liquid water phase.
https://oilandgascorrosion.com/faqs/
slide 50: Charlie Chong/ Fion Zhang
61. What does NACE MR0175 mean by "Qualification based upon field
experience"
Question:
Q1: I need some clarifications on the clause 8.2 of the MR0175/ISO 15156-1
Qualification based upon field experience. “A material may be qualified by
documented field experience”--”the duration of the documented field
experience shall be at least two years. . . “ What kind of documentation is
expected We need to know exactly what to ask from the end user. Is a letter
describing the conditions for which the material qualified for the past two
years enough
Answer:
A1: NACE MR0175/ISO 15156-1 Paragraphs 6.2 8.1 8.2 and 9.0 provide a
complete description of the documentation required for two years’ successful
field service. Documentation has always been required.
ISO 15156-1:2009E
6 Evaluation and definition of service conditions to enable material selection
6.2 The documented service conditions shall be used for one or more of the following purposes:
8.1 Material description and documentation
8.2 Qualification based upon field experience
9 Report of the method of selection or qualification
https://oilandgascorrosion.com/faqs/
slide 51: Charlie Chong/ Fion Zhang
Normal Routes :Qualification based
upon laboratory testing
https://oilandgascorrosion.com/faqs/
Qualification based upon
field experience
Paragraphs 6.2 8.1 8.2 and
9.0 provide a complete
description of the
documentation required
ISO 15156-1:2009E
6 Evaluation and definition of
service conditions to enable
material selection
6.2 The documented
service conditions shall be
used for one or more of the
following purposes:
8.1 Material description and
documentation
8.2 Qualification based upon
field experience
9 Report of the method of
selection or qualification
slide 52: Charlie Chong/ Fion Zhang
Normal Routes :Qualification based upon laboratory testing
https://oilandgascorrosion.com/faqs/
Paragraphs 6.2 8.1 8.3 and 9.0
provide a complete description of the
documentation required
ISO 15156-1:2009E
6 Evaluation and definition of
service conditions to enable
material selection
6.2 The documented
service conditions shall be
used for one or more of the
following purposes:
8.1 Material description and
documentation
8.3 Qualification based upon
laboratory testing
9 Report of the method of
selection or qualification
slide 53: Charlie Chong/ Fion Zhang
Normal Routes :Selection of materials resistant to SSC/SCC in the presence of
sulfides from existing lists and tables
https://oilandgascorrosion.com/faqs/
Paragraphs 6.2 7 and 9.0 provide a
complete description of the
documentation required
ISO 15156-1:2009E
6 Evaluation and definition of
service conditions to enable
material selection
6.2 The documented
service conditions shall be
used for one or more of the
following purposes:
7 Selection of materials
resistant to SSC/SCC in the
presence of sulfides from
existing lists and tables
9 Report of the method of
selection or qualification
slide 54: Charlie Chong/ Fion Zhang
Q2: What do we the equipment manufacturer do with this documentation
field service qualification
A2:The equipment user is responsible for the preparation of the required
documentation see NACE MR0175/ISO 15156-1 Clause 9 Paragraph 1 to
support the use of a material in a plant on the basis of field experience. It
would also be in the equipment user’s interest to keep copies of this
documentation in their records in case they are challenged to prove they are
responsible operators. The equipment manufacturer can choose to retain a
copy for future reference.
https://oilandgascorrosion.com/faqs/
slide 55: Charlie Chong/ Fion Zhang
Q3: Does it have to be filed with NACE If yes is this our responsibility
A3: It is not the responsibility of the equipment manufacturer to file
information with NACE unless they choose to. This may be the case because
the equipment manufacturer has made the effort to compile a non-proprietary
database that they believe supports the use of alloys for their equipment
under the conditions documented by the process in Question One.
Q4: If filing field service documentation with NACE is not required do we
have to verify the claims or can we just provide the materials as requested by
the end user
A4: The manufacturer can provide this information to a user but it is the
user’s responsibility to determine the operating conditions and select the
appropriate materials. It is the manufacturer’s responsibility to meet the
metallurgical requirements of the appropriate alloys in NACE MR0175/ISO
15156.
This question is in relation to NACE MR0175/ISO 15156-1 Clause 8.2
Reference: ISO 15156 Maintenance Panel Inquiry 2004-05
https://oilandgascorrosion.com/faqs/
slide 56: Charlie Chong/ Fion Zhang
Qualification based upon field experience
The duration of the documented field experience shall be at least two years
https://oilandgascorrosion.com/faqs/
slide 57: Charlie Chong/ Fion Zhang
Qualification based upon field experience
The duration of the documented field experience shall be at least two years
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slide 58: Charlie Chong/ Fion Zhang
Qualification based upon field experience
The duration of the documented field experience shall be at least two years
https://oilandgascorrosion.com/faqs/
slide 59: Charlie Chong/ Fion Zhang
……….. It would also be in the equipment
user’s interest to keep copies of this
documentation in their records in case they
are challenged to prove they are
responsible operators.
https://oilandgascorrosion.com/faqs/
slide 60: Charlie Chong/ Fion Zhang
62. What happens to equipment and material certified to old NACE
MR0175 versions
Question:
How should existing equipment affected by changing materials requirements
in later editions of the standard be handled
Answer:
By convention a new version of the standard is not applied retrospectively to
equipment built to the previous version of the standard valid at the time of
equipment construction.
New requirements in the latest version may be applied retrospectively by an
equipment user or mandated for retrospective application by a regulatory
authority.
This question is in relation to NACE MR0175/ISO 15156-1 Clause 8.2
Reference: ISO 15156 Maintenance Panel Inquiry 2005-10
https://oilandgascorrosion.com/faqs/
slide 61: Charlie Chong/ Fion Zhang
Retrospectively
retrospective
said of data already collected or of events that have already occurred. Hence
a retrospective study is a study of past events in contradistinction to a
prospective study.
https://oilandgascorrosion.com/faqs/
https://dictionary.cambridge.org/dictionary/english/retrospectively
https://medical-dictionary.thefreedictionary.com/retrospectively
Compliances
slide 62: Charlie Chong/ Fion Zhang https://oilandgascorrosion.com/faqs/
slide 63: Charlie Chong/ Fion Zhang
By convention a new version of the standard is not
applied retrospectively to equipment built to the
previous version
https://oilandgascorrosion.com/faqs/
slide 64: Charlie Chong/ Fion Zhang
In “Simple English”:
New certified equipment complied with the prevision revision standard if
required
Old certified equipment complied only with the standard during time of
certification and before that
https://oilandgascorrosion.com/faqs/
slide 65: Charlie Chong/ Fion Zhang
In “Simple English”:
New certified equipment complied with the prevision revision standard if
required
Old certified equipment complied only with the standard during time of
certification and before that
https://oilandgascorrosion.com/faqs/
slide 66: Charlie Chong/ Fion Zhang
In “Simple English”:
New certified equipment complied with the prevision revision standard if
required
Old certified equipment complied only with the standard during time of
certification and before that
https://oilandgascorrosion.com/faqs/
slide 67: Charlie Chong/ Fion Zhang
63. Equipment of a SAGD plant is it covered by NACE MR0175
Question: Regarding Table 1 in NACE MR0175/ISO 15156-2 is it defined
what field facilities and field processing plants include Would this include a
SAGD plant Also when using below 65 psi for exclusion does this stand true
for all: liquid vapour or mixed streams also in Table 1
Answer:
SAGD plant is not specifically included in Table 1 because it is not a
“conventional” technique of oil production. However it is up to the user to
determine if some parts of a SAGD process may fit with the listed permitted
exclusions. Please refer to answer to Inquiry 2009-14 for the second part of
the question.
This question is in relation to NACE MR0175/ISO 15156-2
Reference: ISO 15156 Maintenance Panel Inquiry 2010-01
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slide 68: Charlie Chong/ Fion Zhang
SAGD- Steam-assisted gravity drainage
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slide 69: Charlie Chong/ Fion Zhang
SAGD- Steam-assisted gravity drainage
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slide 70: Charlie Chong/ Fion Zhang
SAGD- Steam-assisted gravity drainage
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slide 71: Charlie Chong/ Fion Zhang
SAGD- Steam-assisted gravity drainage
Steam Generator and Injection Trees
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slide 72: Charlie Chong/ Fion Zhang
64. NACE MR0175 and the definition of pressure-containing parts “parts
whose failure would result in a release“
Question:
Definition of pressure-containing parts: “Those parts whose failure to function
as intended would result in a release of retained fluid to the atmosphere.
Examples are valve bodies bonnets and stems.” Are stems always defined
as pressure-containing parts regardless of features that by design keep the
stem intact Example 1: Internal entry stems for ball valves that have a
shoulder that rests against the body around the stem bore. Example 2:
Shafts for butterfly valves that have a retaining ring holding the shaft inside
the valve.
Answer:
NACE MR0175/ISO 15156 cannot interpret design issues.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 3.14
Reference: ISO 15156 Maintenance Panel Inquiry 2003-12 Q2.
https://oilandgascorrosion.com/faqs/
slide 73: Charlie Chong/ Fion Zhang
The original inquiry to the NACE MR0175 Maintenance Panel is below
Question: Definition of pressure-containing parts: “Those parts whose failure
to function as intended would result in a release of retained fluid to the
atmosphere. Examples are valve bodies bonnets and stems.” Are stems
always defined as pressure-containing parts regardless of features that by
design keep the stem intact Example 1: Internal entry stems for ball valves
that have a shoulder that rests against the body around the stem bore.
Example 2: Shafts for butterfly valves that have a retaining ring holding the
shaft inside the valve.
Answer:
NACE MR0175/ISO 15156 cannot interpret design issues.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 3.14
Reference: ISO 15156 Maintenance Panel Inquiry 2003-12 Q2.
https://oilandgascorrosion.com/faqs/
slide 74: Charlie Chong/ Fion Zhang
65. Is HIC Resistance "included" when specifying NACE MR0175
Question:
Does requiring/specifying steel compliance to ANSI/NACE MR0175/ISO 15156-2 in a
purchase order include resistance to HIC as well as other forms of sulfide cracking or
must HIC resistance be specifically required separately in the purchase order
Answer:
ISO 15156 / NACE MR0175 covers all cracking mechanisms caused by H2S to be
addressed for materials exposed in production environments. This includes HIC/SWC
as stated in the scope for Part 2. Section 8 in ISO 15156 / NACE MR0175 Part 2
describes how carbon and low alloy steels shall be evaluated for their resistance to
HIC/SWC. Test procedures and acceptance criteria to evaluate the resistance of
carbon and low-alloy steels to HIC/SWC are described in B.5.
As only flat-rolled carbon steel products are susceptible to HIC/SWC section 5.2
requires that “requirements for HIC resistance” are provided in the purchasing
specification. Note that a list of information must be included in the purchase order
note also the use of the word “shall” in the section that includes “requirements for
HIC resistance”.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 5.2
Reference: ISO 15156 Maintenance Panel Inquiry 2014-02
https://oilandgascorrosion.com/faqs/
slide 75: Charlie Chong/ Fion Zhang
8 Evaluation of carbon and low alloy steels for their resistance to
HIC/SWC
The equipment user shall consider HIC/SWC as defined in ISO 15156-1 when
evaluating flat-rolled carbon steel products for sour service environments containing
even trace amounts of H2S and shall consider HIC/SWC testing of these products.
Annex B provides guidance on test methods and acceptance criteria to evaluate
resistance to HIC/SWC. The probability of HIC/SWC is influenced by steel chemistry
and manufacturing route. The level of sulfur in the steel is of particular importance
typical maximum acceptable levels for flat-rolled and seamless products are 0003
mass fraction and 001 mass fraction respectively. Comparison purposes on
seamless Conventional forgings with sulfur levels less than 0025 mass fraction
and castings are not normally considered sensitive to HIC or SOHIC.
NOTE 1 HIC/SWC leading to loss of containment has occurred only rarely in seamless
pipe and other products that are not flat-rolled. Furthermore seamless pipe
manufactured using modern technology is much less sensitive to HIC/SWC than older
products. Hence there can be benefits in evaluating seamless pipe for HIC/SWC
resistance for applications where the potential consequences of failure make this
justifiable.
NOTE 2 The presence of rust sulfur or oxygen particularly together with chloride in
the service environment is thought to increase the probability of damage.
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slide 76: Charlie Chong/ Fion Zhang
The severity to HIC/SWC of Flat-
Rolled products w.r.t others was
highlighted
The level of sulfur in the steel is of particular
importance typical maximum acceptable levels for flat-
rolled and seamless products are 0003 mass
fraction and 001 mass fraction respectively.
Conventional forgings with sulfur levels less
than 0025 mass fraction and castings
are not normally considered sensitive
to HIC or SOHIC.
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slide 77: Charlie Chong/ Fion Zhang
The severity to HIC/SWC of Flat-
Rolled products w.r.t others was
highlighted
All product forms are
sensitive to HIC/SWC
damage in one way
or others
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slide 78: Charlie Chong/ Fion Zhang https://oilandgascorrosion.com/faqs/
slide 79: Charlie Chong/ Fion Zhang https://oilandgascorrosion.com/faqs/
slide 80: Charlie Chong/ Fion Zhang
66. In NACE MR0175 Is a welding consumable with a nickel content of
1.03 acceptable
Question: Is a welding consumable with a nickel content of 1.03
acceptable or is 1.00 the maximum allowed
Answer:
For carbon and low-alloy steels 1 nickel has been set to be the maximum
to avoid SSC. However a value above 1 could be used if it is qualified as
stated in A.2.1.4. It is not the role of the Maintenance Panel to give an opinion
on a specific metallurgical issue.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 5.3.1.4
Reference: ISO 15156 Maintenance Panel Inquiry 2009-20
https://oilandgascorrosion.com/faqs/
slide 81: Charlie Chong/ Fion Zhang
ISO 15156-2:2015E
A.2.1.4 Welding
Welding and weld-hardness determinations shall be performed in accordance
with 7.3.3. Acceptable maximum hardness values for carbon steel carbon
manganese steel and low alloy steel welds are given in Table A.1.
……… Welding consumables and procedures that produce a deposit
containing more than 1 mass fraction nickel are acceptable after successful
weld SSC qualification by testing in accordance with Annex B.
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slide 82: Charlie Chong/ Fion Zhang
67. Difference between the NACE MR0175 requirements of SSC and
HIC/SWC
Question: There is ambiguity between two passages they contradict paragraph
7.2.1.2 “SSC regions of environmental severity” of NACE MR0175/ISO 15156-2:2009
E to 17 Paragraph 8 “Evaluation of carbon and low alloy steels for their resistance to
HIC/SWC” of NACE MR0175/ISO 15156 – 2:2009 E The paragraph 7.2.1.2 for
Region 0 – For pH2S 0.3 kPa 0.05 psi “ Normally no precautions are required for
the selection of steels for use under these conditions whereas paragraph 8 says
even trace amounts of H2S and shall consider HIC/SWC testing of these products” In
addition the Sulfur restriction in the chemistry of.003 maximum.
Answer:
“Your quoted passages of the standard are not contradictory. The standard provides
different qualification requirements for different materials and different potential
cracking modes. Clause 7 is for “- - steels with resistance to SSC SOHIC and SZC”.
7.2.1.2 7.2.1.3 are only applicable to SSC. Clause 8 is for “Evaluation of carbon and
low alloy steels for their resistance to HIC/SWC”. For carbon steel products made from
rolled plate in addition to consideration of SSC resistance HIC/SWC shall be
considered clause 8 and SOHIC and SCZ should be considered clause 7.2.2.”
This question is in relation to NACE MR0175/ISO 15156-2 Clause 7.2.1.2
Reference: ISO 15156 Maintenance Panel Inquiry 2012-09
https://oilandgascorrosion.com/faqs/
slide 83: Charlie Chong/ Fion Zhang
68. In NACE MR0175 what does the uncertainty below 0.3 kPa mean
Question:
There is the sentence in the note 1 of Figure 1 in ISO 15156-2: "The
discontinuities in the figure below 0.3 kPa 0.05 psi and above 1 MPa 150
psi partial pressure H2S reflect uncertainty with respect to the measurement
of H2S partial pressure low H2S and steels performance outside these limits
both lower and higher H2S." I understand the above sentence and if I will
use the carbon steel and low-alloy steel in the sour service above 1 MPa 150
psi of partial pressure of H2S what can I do Should I require a special
laboratory test imitating the H2S partial pressure and pH in the service for
SSC of the carbon steel and low-alloy steel Which solution can I use in the
special laboratory test NACE TM0177 A solution or the imitating solution in
the service
Keywords:
uncertainty with respect to the measurement of H2S partial pressure
uncertainty steels performance outside these limits
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slide 84: Charlie Chong/ Fion Zhang
Answer:
The following response must be seen in the context of NACE MR0175/ISO 15156-2
Clause 7.
1. NACE MR0175/ISO 15156-2 Fig. 1 is a schematic definition of Regions of
environmental severity with respect to SSC of carbon and low alloy steels. As
mentioned in Paragraph 7.2.1.4 qualification for the use of a material not listed in
Annex A for use in one or more of the Regions of Fig. 1 is always dependent on
reported field experience or laboratory testing.
There is little documented evidence that describes the SSC resistance of carbon
and low alloy steels in H2S-containing environments outside the H2S limits of
Fig. 1. The Note quoted reflects this.
2. The equipment user must decide whether the listing of a steel in Annex A serves
as an adequate guide for its behavior in H2S-containing field environments that
might be more severe with respect to SSC than those represented by the SSC
testing methods normally used see Annex B.1a. For qualification for a specific
application all the test conditions must be at least as severe with respect to the
potential mode of failure as those expected to occur in field service.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 7.2.1.2 Fig 1
Reference: ISO 15156 Maintenance Panel Inquiry 2005-17
https://oilandgascorrosion.com/faqs/
slide 85: Charlie Chong/ Fion Zhang
69. Does NACE MR0175/ISO 15156 require production casing to be sour
service compliant
Question: Does NACE MR0175/ISO 15156 require production casing to be sour
service compliant if the containment string of tubing is a sour service grade and the
bottom hole temperature below the packer satisfies the casing material operating
temperature For example--a sour gas well with a H2S partial pressure of 0.10 psi
0.007 bar P-110 casing L-80 tubing and a bottom hole temperature of 300 F 150
C. Supporting Information: Related information can be found in NACE MR0175/ISO
15156-2 Table 1 page 2.
Production casing is not excluded from meeting the requirements of ISO 15156. AND
ISO 15156-1/NACE MR0175 Section 6 which is reproduced in part below with the
relevant parts underlined.
6. Evaluation and definition of service conditions to enable material selection
6.1 Before selecting or qualifying materials using other parts of NACE MR0175/ISO
15156 the user of the equipment shall define evaluate and document the service
conditions to which materials may be exposed for each application. The defined
conditions shall include both intended exposures and unintended exposures which
may result from the failure of primary containment or protection methods. Particular
attention shall be paid to the quantification of those factors known to affect the
susceptibility of materials to cracking caused by H2S.
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slide 86: Charlie Chong/ Fion Zhang
Answer:
1. As stated in your inquiry the secondary barrier must also be sour service
and follow the requirements of NACE MR0175/ISO 15156.
2. A casing grade can be used under severity 3 of the diagram Fig. 1 of §
7.2.1.2. provided its working temperature is always above the minimum
temperature given in ISO 15156-2 Table A.3. This can only be true if the
material is well defined API grade and its temperature is always above
the minimum temperature. According to Table A.3 if P110 is at a
temperature ≥80°C 175°F it can be used in Region 3 of the diagram
Figure 1 of §7.2 in ISO 15156-2. It is up to the equipment user to
establish that all intended and unintended exposure conditions are
covered.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 7.2.1.2
Reference: ISO 15156 Maintenance Panel Inquiry 2010-12
https://oilandgascorrosion.com/faqs/
slide 87: Charlie Chong/ Fion Zhang https://oilandgascorrosion.com/faqs/
containment
string of
tubing
slide 88: Charlie Chong/ Fion Zhang
https://oilandgascorrosion.com/faqs/
slide 89: Charlie Chong/ Fion Zhang
Downhole tubing material selection for Region 1/2/3
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A.4 SSC-resistant steels for use throughout SSC region 1
A.4.2 Downhole casing tubing and tubular components
Casing tubing and tubular components made of Cr-Mo low-alloy steels
UNS G41XX0 formerly AISI 41XX and modifications have proven
acceptable in the quenched and tempered condition. Typically the actual
yield strength of acceptable steels has been no more than 896 MPa 130
ksi an SMYS of approximately 760 MPa 110 ksi and their hardness
has been no more than 30 HRC. Other requirements shall be in
accordance with the applicable manufacturing specification.
A.3 SSC-resistant steels for use throughout SSC region 2
A.3.2 Downhole casing tubing and tubular components
Casing tubing and tubular components made of Cr-Mo low-alloy steels
UNS G41XX0 formerly AISI 41XX and modifications have proven
acceptable in the quenched and tempered condition.
Typically the actual yield strength of acceptable steels has been no more
than 760 MPa 110 ksi an SMYS of approximately 550 MPa 80 ksi
and their hardness has been no more than 27 HRC. Other requirements
shall be in accordance with the applicable manufacturing specification.
A.2 SSC-resistant carbon and low-alloy steels and the use of cast
irons
A.2.2.3 Downhole casing tubing and tubular components
A.2.2.3.1 ISO and API grades of casing and tubing are acceptable
for the temperature ranges given in Table A.3.
slide 90: Charlie Chong/ Fion Zhang
Table A.3 — Environmental conditions for which grades of casing and
tubing are acceptable
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slide 91: Charlie Chong/ Fion Zhang
ISO 15156-2:2015E
Table 1 — List of equipment
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slide 93: Charlie Chong/ Fion Zhang
Charlie Chong/ Fion Zhang
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70. Does ISO 15156-2 7.3.2 also apply to low-alloy martensitic steels
such as CA6NM
Question:
Does the MR0175/ISO 15156-2 7.3.2 also apply to low-alloy martensitic
steels such as CA6NM which is in fact considered a CRA MR0175/ISO
15156-3
Answer:
No it does not. Please see ISO 15156-3 6.2.1 and ISO 15156-3 A.6.2 Table
A18.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 7.3.2 and
7.3.3
Reference: ISO 15156 Maintenance Panel Inquiry 2004-18 Q2
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slide 95: Charlie Chong/ Fion Zhang
71. In NACE MR0175 does “Hardness of parent metals” apply to
machined forgings just to weldment parent metals
Question:
Do NACE MR0175/ISO 15156-2 7.3.2 “Parent metals” and NACE
MR0175/ISO 15156-3 6.2.1 “Hardness of parent metals” apply to machined
forgings or are they meant to be applied to weldment parent metals only
Answer:
The requirements listed in NACE MR0175/ISO 15156-2 Section 7.3.2 apply
to the parent materials applicable to part 2 carbon and low alloy steels and
cast irons. The parent materials include forgings. See also sections A.2.1.2
and A.2.1.3 of Annex A for additional requirements. The requirements listed in
NACE MR0175/ISO 15156-3 Section 6.2.1 apply to parent materials
applicable to part 2 CRAs and other alloys. The parent materials include
forgings
This question is in relation to NACE MR0175/ISO 15156-3 Clause 6.2.1
Reference: ISO 15156 Maintenance Panel Inquiry 2014-03
https://oilandgascorrosion.com/faqs/
slide 96: Charlie Chong/ Fion Zhang
72. For Hardness vickers HV What is NACE MR0175 retesting criteria
Question:
Typically when an indentation fails the micro hardness test several additional
indentations are made and measured in the same area as the suspect
indentation on the same weld test coupon. The results are then averaged. If
the additional indentations average is acceptable the survey is considered
acceptable. This is in line with the NACE MR0175 Part 2 Section 7.3
“Hardness” paragraph 7.3.2 “Parent Materials” which allows additional
hardness readings in the adjacent areas of a failed hardness reading.
Logically the same testing methodology would apply to welds even though it
is not specifically stated in the standard and subsequent paragraphs of Part 2.
I would like to clarify if the above is acceptable with regards to Vickers HV 10
micro hardness testing / re-testing requirements for welds while conforming to
NACE MR0175 Section 7.3.3 Welds.
Answer:
Maximum acceptable hardness values for carbon steel carbon-manganese
steel and low-alloy steel welds are given in Table A.1.
No individual readings above these limits are acceptable for welds.
Reference: ISO 15156 Maintenance Panel Inquiry 2014-07
https://oilandgascorrosion.com/faqs/
slide 97: Charlie Chong/ Fion Zhang
Parent Material Hardness:
Individual HRC readings exceeding the
value permitted by this part of ISO 15156
may be considered acceptable if the
average of several readings taken within
close proximity does not exceed the value
permitted by this part of ISO 15156 and no
individual reading is greater than 2 HRC
above the specified value.
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slide 98: Charlie Chong/ Fion Zhang
Weld Material Hardness:
Maximum acceptable hardness
values for carbon steel carbon-
manganese steel and low-alloy
steel welds are given in Table A.1.
No individual readings above these
limits are acceptable for welds.
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slide 99: Charlie Chong/ Fion Zhang
Heat Affected Zone Hardness:
HAZ is Parent Material
HAZ is Weld
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slide 100: Charlie Chong/ Fion Zhang
ISO 15156-2:2015E
7.3 Hardness requirements
7.3.2 Parent metals
If hardness measurements on parent metal are specified sufficient hardness
tests shall be made to establish the actual hardness of the steel being
examined. Individual HRC readings exceeding the value permitted by this
part of ISO 15156 may be considered acceptable if the average of several
readings taken within close proximity does not exceed the value permitted by
this part of ISO 15156 and no individual reading is greater than 2 HRC above
the specified value. Equivalent requirements shall apply to other methods of
hardness measurement when specified in this part of ISO 15156 or
referenced in a manufacturing specification.
NOTE The number and location of hardness tests on parent metal are not
specified in ISO 15156.
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slide 101: Charlie Chong/ Fion Zhang
7.3.3 Welds
The qualification of welding procedures for sour service shall include
hardness testing in accordance with 7.3.3.2 7.3.3.3 and 7.3.3.4.
7.3.3.4 Hardness acceptance criteria for welds
Weld hardness acceptance criteria for steels selected using option 1 see 7.1
shall be as specified in A.2.1.4.
Alternative weld hardness acceptance criteria may be established from
successful SSC testing of welded samples. SSC testing shall be in
accordance with Annex B. Weld-hardness acceptance criteria for steels
qualified and/or selected using option 2 see 7.2 may be established from
successful SSC testing of welded samples. SSC testing shall be in
accordance with Annex B.
A.2.1.4 Welding
Welding and weld-hardness determinations shall be performed in accordance
with 7.3.3. Acceptable maximum hardness values for carbon steel carbon
manganese steel and low alloy steel welds are given in Table A.1.
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slide 102: Charlie Chong/ Fion Zhang
73. Seal welding of vent holes on saddle plates welded to pipe do they
need to comply with NACE MR0175
Question:
Seal welding of vent holes on saddle plates welded to pipe. We have provided vent
holes on saddle plates in accordance with ASME B31.3. We have used these saddle
plates at support locations as a protective shield to pipe. Now we would like to close
the vent hole by seal welding after completion of saddle welding with pipe and carrying
out PWHT. Permanent closing of vent hole is required to avoid corrosion in offshore
conditions. Service is crude oil with H2S i.e. NACE MR0175/ISO 15156 is applicable.
Kindly advise us about the acceptance of seal welding for these service conditions.
Answer:
The ISO 15156 Maintenance Panel cannot provide guidance on the acceptability of
seal welding in this application.
It is the responsibility of the equipment user to decide whether NACE MR0175/ISO
15156-2 is applicable to these seal welds. The applicability of this standard is
described in Clause 1 Scope. If this standard is considered applicable then the seal
welds must comply with the requirements of NACE MR0175/ISO 15156-2 7.3.3 or
NACE MR0175/ISO 15156-3 6.2.2.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 7.3.3
Reference: ISO 15156 Maintenance Panel Inquiry 2005-21
https://oilandgascorrosion.com/faqs/
slide 103: Charlie Chong/ Fion Zhang
Pressure Vessel and Pipe Support Plates
Vessel
support lug’s
attachment
plate
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slide 104: Charlie Chong/ Fion Zhang
Pressure Vessel and Pipe Support Plates
Pipe support
saddle plate
with bleed
hole
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slide 105: Charlie Chong/ Fion Zhang
Pressure Vessel and Pipe Support Plates
Pipe support
saddle plate
with bleed
hole
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slide 106: Charlie Chong/ Fion Zhang
TROLL C- Offshore Piping and Process Vessels
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slide 107: Charlie Chong/ Fion Zhang
74. In the NACE MR0175 butt weld survey criteria what is the
acceptance criteria of middle points
Question:
Ref Part 2 Figure 2 Butt Weld Survey method for Vickers Hardness
Measurement. Location points 17 18 19. What are the acceptance criteria
Table A.1 only provides acceptance for the Weld Cap and Root. As the area is
not exposed should the acceptance level be 275 HV 10
Answer:
Since it is not at the cap the acceptance level should be 250 HV 10 unless it
is proven that it can be relaxed. For now there is no demonstrated evidence
to show that 250 Hv can be relaxed at location points 17 18 and 19 of Part 2
Figure 2.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 7.3.3
Figure 2 Table A.1
Reference: ISO 15156 Maintenance Panel Inquiry 2009-04
https://oilandgascorrosion.com/faqs/
slide 108: Charlie Chong/ Fion Zhang
Hardness Survey Indentation Points
919
indentations-
Weld root
12345678
indentations –
Weld cap
919
indentations-
Weld root
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slide 109: Charlie Chong/ Fion Zhang
Table A.1 — Maximum acceptable hardness values for carbon steel
carbon-manganese steel and low-alloy steel welds
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slide 110: Charlie Chong/ Fion Zhang
75. Is it acceptable to use HV 500g microhardness testing for NACE
applications for WPS qualification
Question:
Is it acceptable to use HV 500g microhardness testing for NACE
applications for WPS qualification I understand that Paragraph 7.3.3.2 of
NACE MR0175/ISO 15156 Part 2 says that hardness testing shall normally
be carried out using HV 10kg or HV 5kg which is our usual practice. FYI the
hardness testing was done with HV 500g on CSA Z245.1 Grade 359 pipe
material.
Answer:
Yes subject to the agreement of the equipment user. Please see NACE
MR0175/ISO 15156-2 Para. 7.3.3.2.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 7.3.3.2
Reference: ISO 15156 Maintenance Panel Inquiry 2006-08
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slide 111: Charlie Chong/ Fion Zhang
76. According to NACE MR0175 is 22HRC and PWHT required
Question:
Section 7.3.3.2 states: "The HRC method may be used for welding procedure
qualification. . . And the welding procedure specification includes post-weld heat
treatment" and Clause A.2.1.4 states: "As-welded carbon steels carbon manganese
steels and low alloy steels that comply with the hardness requirements of Table A.1 do
not require postweld heat treatment." It is confusing whether the latter statement
implies that an as-welded carbon steel carbon manganese steel or low alloy steel
would require a PWHT if only HRC hardness testing is performed. Per Section 7.3.3.2
I would say yes it does require PWHT. But if the as-welded hardness survey meets the
22 HRC limit then doesnt the as-welded material "comply with the hardness
requirements of Table A.1 as stated in clause A.2.1.4
Answer:
For carbon carbon manganese and low alloy steels hardness testing for welding
procedure qualification PQR may be performed by the HRC method only if the
design stress does not exceed 2/3 SMYS and PWHT is perform. If PQR hardness
testing is performed by the 7.3.3.2 specified HV or HR15N methods the restrictions
for design stress and PWHT are not required.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 7.3.3.2
Reference: ISO 15156 Maintenance Panel Inquiry 2011-14
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slide 112: Charlie Chong/ Fion Zhang
Post Weld Heat Treatment
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slide 113: Charlie Chong/ Fion Zhang
Post Weld Heat Treatment
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slide 114: Charlie Chong/ Fion Zhang
77. In NACE MR0175 what does "as close as possible to but no more
than 1mm from the fusion boundary" mean
Question:
Per 7.3.3.3 Using the Vickers or Rockwell 15N measurement methods
hardness impressions 2 6 and 10 should be entirely within the heat-affected
zone and located as close as possible to but no more than 1mm from the
fusion boundary between the weld overlay and HAZ." Is a correct
interpretation that when welding dissimilar metals such as corrosion resistant
overlays on low alloy steels the phrase "as close as possible to but no more
than 1mm from the fusion boundary" means that the indentation should be
no less than 3x the mean diagonal length of the indentation from the fusion
boundary as is required for adjacent indentations in ISO 6507-1:1998 Note:
ISO 6507-1:1998 is referenced by NACE/ISO 15156-2 in the first paragraph
of Section 7.3.3.2 Hardness testing methods for welding procedure
qualification.
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slide 115: Charlie Chong/ Fion Zhang
Answer:
The ISO 15156 Maintenance Panel cannot provide an interpretation of the
ISO 6507-1:1998 in relation to the minimum distance of hardness
indentations from the boundary between the base metal and the overlay weld.
As stated in ISO 15156-2 7.3.3.2 and ISO 15156-3 6.2.2.2.2 hardness
measurements can also be carried out using a smaller indentation load for
example HV5 rather than HV10 and in many cases this will allow compliance
with the requirements of ISO 15156-2 Fig. 6.
It is important to recognize that there will be a gradient in HAZ hardness in
any case and thus measurements too far from the fusion boundary could be
un-conservative.
In all cases it is the task of the equipment user and hence the supplier to
ensure that the hardness values measured are the most representative
possible of the cracking resistance of the welded material in any sour service
it is expected to experience.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 7.3.3.3
Reference: ISO 15156 Maintenance Panel Inquiry 2006-01Q2
https://oilandgascorrosion.com/faqs/
slide 116: Charlie Chong/ Fion Zhang
In all cases it is the task of the equipment user and hence the supplier to
ensure that the hardness values measured are the most representative
possible of the cracking resistance of the welded material in any sour service
it is expected to experience.
https://oilandgascorrosion.com/faqs/
slide 117: Charlie Chong/ Fion Zhang
78. About welds in accordance with NACE MR0175/ISO 15156 Part 2 Item
7.3.3.4 "hardness acceptance criteria for welds" "weld hardness acceptance
criteria for steels selected using option 1 see 7.1 shall be as specified in
A.2.1.4. Alternative weld hardness acceptance criteria may be established
from successful SSC testing of welded samples. SSC testing shall be in
accordance with Annex B." So in our understanding if our welding procedure
qualifications WPSs are qualified in accordance with NACE MR0175/ISO
15156 Part 2 Item A.2.1.4 it is not necessary to test them according to
NACE TM0177. We would like you to confirm whether our interpretation
below is correct and if not give us the correct interpretation.
https://oilandgascorrosion.com/faqs/
slide 118: Charlie Chong/ Fion Zhang
Question:
About welds in accordance with NACE MR0175/ISO 15156 Part 2 Item
7.3.3.4 “hardness acceptance criteria for welds” “weld hardness acceptance
criteria for steels selected using option 1 see 7.1 shall be as specified in
A.2.1.4. Alternative weld hardness acceptance criteria may be established
from successful SSC testing of welded samples. SSC testing shall be in
accordance with Annex B.”
So in our understanding if our welding procedure qualifications WPSs are
qualified in accordance with NACE MR0175/ISO 15156 Part 2 Item A.2.1.4
it is not necessary to test them according to NACE TM0177. We would like
you to confirm whether our interpretation below is correct and if not give us
the correct interpretation.
Answer:
Your interpretation is correct.
https://oilandgascorrosion.com/faqs/
slide 119: Charlie Chong/ Fion Zhang
7.3.3.4 Hardness acceptance criteria for welds
Weld hardness acceptance criteria for steels selected using option 1 see 7.1
shall be as specified in A.2.1.4.
Alternative weld hardness acceptance criteria may be established from
successful SSC testing of welded samples. SSC testing shall be in
accordance with Annex B.
Weld-hardness acceptance criteria for steels qualified and/or selected using
option 2 see 7.2 may be established from successful SSC testing of welded
samples. SSC testing shall be in accordance with Annex B.
Complying with hardness is the
mandatory requirement for welding of
material selected from Appendix A.
All selected material including weld
consumable shall be within the App.
A specified
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slide 120: Charlie Chong/ Fion Zhang
Question:
NACE MR0175/ISO 15156 and NACE TM0177–WELDS
On the other hand if we make the test in accordance with NACE TM0177 in our
WPSs that are previously qualified to conform to NACE MR0175/ISO 15156 what
kind of results will we have Will we have necessary or redundant results
Answer:
A manufacturer may choose to qualify a welding procedure specification in
accordance with ANNEX B. Testing welds acceptable in accordance with A.2.1.4 is an
optional activity chosen by the manufacturer to confirm resistance to cracking. This is
not necessarily a redundant result depending on the anticipated service conditions
and the selected test environment the results could be used:
to confirm that the hardness control specified in A.2.1.4 is adequate to prevent
sulfide stress cracking
or to define alternative weld hardness control requirements that will not lead to
sulfide stress cracking when the requirements of A.2.1.4 are not met.
Reference: ISO 15156 Maintenance Panel Inquiry 2005-08 Q1 Q2 and Q3
This question is in relation to NACE MR0175/ISO 15156-1 Clause 7
https://oilandgascorrosion.com/faqs/
slide 121: Charlie Chong/ Fion Zhang
NACE TM0177 Testing
https://oilandgascorrosion.com/faqs/
slide 122: Charlie Chong/ Fion Zhang
NACE TM0177 Testing
https://oilandgascorrosion.com/faqs/
slide 123: Charlie Chong/ Fion Zhang
80. According to NACE MR0175/ISO 15156 is there a maximum sulfur
content for carbon steel SMLS pipe
Question:
According to NACE MR0175/ISO 15156 Part 2 Paragraph 8 HIC test is not
mandatory for carbon steel SMLS pipe. But what about maximum sulfur
content Do we have to apply maximum sulfur content requirement to carbon
steel regardless of HIC test
Answer:
There are no requirements for the control of the chemistry of any elements to
prevent HIC in NACE MR0175/ISO 15156. Some guidance concerning
acceptable sulfur levels is given in Section 8 of NACE MR0175/ISO 15156
Part 2. For seamless products testing can also be performed according to
Table B.3 if deemed necessary.
This question relates to Part 2 paragraph 8
Reference: ISO 15156 Maintenance Panel Inquiry 2005-15
https://oilandgascorrosion.com/faqs/
slide 124: Charlie Chong/ Fion Zhang
81. What is NACE MR0175 acceptance criteria for HIC / NACE TM0284
Question: It appears that ISO 15156-2 is ambiguous in defining the acceptance criteria for HIC
testing. Section B.5 and Table B.3 refer to NACE TM0284. This TM prescribes CLR CTR and
CSR results to be reported for each of the three sections taken from a specimen and also as the
average per specimen.
Q1. Could you please confirm that the intention of Section B.5 and Table B.3 is that the
requirements of NACE TM0284 for the evaluation of test specimens should be followed and that
CLR CTR and CSR should be calculated and reported for each section and the average for
each test specimen. Table B.3 does not specify if the criteria apply to the single section numbers
or to the averages per specimen or to the averages over a series of specimens. The last of these
was suggested recently to us for qualification purposes by a materials manufacturer. ISO 3183-
3 the successor to API 5L uses the same CLR CTR and CSR values as criteria as ISO 15156
but in addition it mentions that averages per specimen should be measured against the
acceptance criteria not single section numbers. I think it is common practice to apply this
approach. If one decides that the acceptance criteria are to be applied to single sections I do not
believe that using in addition the same criteria for the average per specimen yields any useful
additional information because it is less restrictive but it does no harm either. If however one
decides that the acceptance criteria are to be applied only to the average per specimen I am of
the opinion that an additional condition should be imposed for single section results or for single
crack lengths for instance no single crack length should exceed 5 mm as part of the overall
acceptance requirements.
https://oilandgascorrosion.com/faqs/
slide 125: Charlie Chong/ Fion Zhang
Q2. Are the acceptance criteria intended to apply to the test results of both
single section and the average per specimen
Q3. Is the intention that in coming to a qualification the CLR CTR and CSR
values be calculated by averaging the results for a series of specimens
Q4. If they are intended to apply to only the average per specimen what
additional requirements should be placed on the results of single section
results
ANSI/NACE TM0284-2016 Evaluation of Pipeline and Pressure Vessel Steels for
Resistance to Hydrogen-Induced Cracking
TM0177-2016 Laboratory Testing of Metals for Resistance to Sulfide Stress
Cracking and Stress Corrosion Cracking in H2S Environments
https://oilandgascorrosion.com/faqs/
slide 126: Charlie Chong/ Fion Zhang
Answer:
A1. Yes.
A2. The referenced standard NACE TM0284 Paragraph 8.4 requires the calculation
and reporting of test results for each of three sections and the average for each test
specimen. The application of the acceptance criteria to single section and/or the
average for a specimen is subject to agreement between equipment user and the
manufacturer.
A3. See Answer A.2 above the referenced standard NACE TM0284 makes no
mention of calculating results by averaging the results for a series of test specimens.
A4. The Maintenance Panel is unable to comment on issues that would involve an
extension of the requirements of the standard. Any materials purchaser is free to add
requirements beyond those required or made optional by the standard. Any
amendment proposal to extend the requirements for single section test results must
be submitted in accordance with the requirements outlined in:-
01. Introduction to ISO 15156 maintenance activities Annex C of the web site
www.iso.org/iso15156maintenance.
This question is in relation to NACE MR0175/ISO 15156-2 Clause 8
Reference: ISO 15156 Maintenance Panel Inquiry 2006-11
https://oilandgascorrosion.com/faqs/
slide 127: Charlie Chong/ Fion Zhang
B.5 Test procedures and acceptance criteria to evaluate the resistance
of carbon and low-alloy steels to HIC/SWC
Test procedures and acceptance criteria shall be in accordance with Table B.3.
Testing shall be performed at ambient temperature 25 °C ± 3 °C 77 °F ± 5
°F.
Unless otherwise indicated test requirements shall be in accordance with
NACE TM0284.
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slide 128: Charlie Chong/ Fion Zhang
Table B.3 — HIC/SWC test procedure and acceptance criteria
slide 129: Charlie Chong/ Fion Zhang
82. NACE MR0175 does not mention clearly about sulfur restrictions for
carbon steels such as ASTM A105 and A216. What are the sulfur limits
NACE MR0175 / ISO 15156 -2 in section 8 states:
"The probability of HIC/SWC is influenced by the steel chemistry and
manufacturing route. The level of sulfur in the carbon and low alloy steel is
of particular importance“
At Oil Gas Corrosion we help clients to develop material specifications that
specify sulfur contents in order to meet NACE MR0175 / ISO 15156 and that
consider integrity threats throughout service life including HIC SWC and
SOHIC.
https://oilandgascorrosion.com/faqs/
slide 130: Charlie Chong/ Fion Zhang
Question: NACE MR0175 /ISO 15156 does not mention clearly about sulfur restrictions for
carbon steel forgings and castings to ASTM-A105 and ASTM-A216 respectively. These two
specs are work-horse of any oil/gas processing industry. Almost 75 to 90 of materials of
construction would fall into these specifications. For example: flanges and fittings and valves and
rotating machinery casings. The paragraph A.2.1.3 states: A.2.1.3 Carbon steels acceptable with
revised or additional restrictions In addition to the restrictions of A.2.1.2 some carbon steels are
acceptable subject to the revised or additional restrictions as follows. a Forgings produced in
accordance with ASTM A 105 are acceptable if the hardness does not exceed 187 HBW. Please
note: In the original standards ASTM-A105 allows sulfur up to 0.040 and ASTM A 216 allows
sulfur up to 0.045. However NACE MR0175/ISO 15156 Section 8 says: Conventional forgings
with sulfur levels less than 0.025 and castings are not normally considered sensitive to HIC
or SOHIC. The above statement means ASTM A 105 forgings are acceptable if sulfur is limited
to 0.025 and hardness to 187 HBW Castings have no additional sulfur limit other than specified
in the base spec. for example: 0.045 for ASTM-A216. The document has reference to many
casting and forging grades but these two grades are not adequately covered. ASTM A 216 is
not covered at all. It would be appreciated if NACE clearly makes mention of these two important
materials with limitations if any clearly stated. Would such changes be possible
Answer:
It is outside the scope of the standard to provide information concerning the "limitations" of ASTM
A 105 and ASTM A 216 in the specific form you request.
slide 131: Charlie Chong/ Fion Zhang
83. Is 243 Brinell acceptable for carbon steels in accordance with NACE
MR0175 / ISO15156-2 Table A.1
Question:
I am writing to you to ask for clarification regarding NACE MR0175/ISO 15156-2 We have a part
here which was welded and PWHT and the subsequent hardness check revealed a hardness on
the weld cap of 243 Brinell. Our engineering department dispositioned this as acceptable in
accordance with Table A.1 as Section A.2.1.4 suggests that "Acceptable maximum hardness
values for carbon steel carbon manganese steel and low-alloy steel welds are given in Table
A.1." An independent Competent Body Lloyds Register however has pointed out that Table A.1
mentions "Hardness test locations for welding procedure qualification" utilizing Vickers and
Rockwell hardness techniques. Can you please therefore confirm if NACE compliant production
welding can be accepted in accordance with this Table or is it merely for weld procedure
qualification.
Answer:
Hardness measurements must be performed according to § 7.3.3 using Vickers hardness HV 10
or 5 or Rockwell 15N methods. Brinell hardness method is subject to the acceptance of the
equipment user.
Table A.1 applies to qualification and production hardness values. However since 243 Brinell is
above 250 HV or 22 HRC but below the alternate weld cap limit of 275 HV it requires “equipment
user” acceptance and also to obey the two other listed requirements in Table A.1.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A T able A.1
Reference: ISO 15156 Maintenance Panel Inquiry 2011-05
https://oilandgascorrosion.com/faqs/
slide 132: Charlie Chong/ Fion Zhang
84. In NACE MR0175 when is a "qualification" required
Question:
Could you please define the word "Qualification." In our understanding
qualification is required for new materials that are not listed in Table A.2 of
NACE MR0175/ISO 15156-2. We would like you to confirm that our
interpretation is correct and if not what is your position
Answer:
Table A.2 of ISO 15156-2 gives examples of materials that can be qualified
provided they comply with Paragraph A.2.1. If not listed in Table A.2
materials must be assessed in the terms of the requirements given in Annex A
as explained in Paragraph 7 of Part 1. Again it is up to the equipment user to
decide if materials need further qualification through testing or field
experience as explained in Paragraph 8 of Part 1.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A T able A.2
Reference: ISO 15156 Maintenance Panel Inquiry 2009-01
https://oilandgascorrosion.com/faqs/
slide 133: Charlie Chong/ Fion Zhang
85. In NACE MR0175 does the term “hot rolled” only apply to sheet or
plate material and cannot be applied to the forming of butt weld fittings
Question:
Does the term “hot rolled” referred to in Paragraph A.2.1.2 only apply to sheet
or plate material and as such cannot be applied to the forming of butt weld
fittings
Answer:
Yes “hot rolled” in the view of the Maintenance Panel does not apply to the
forming of butt weld fittings.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A.2.1.2
Reference: ISO 15156 Maintenance Panel Inquiry 2004-06
https://oilandgascorrosion.com/faqs/
slide 134: Charlie Chong/ Fion Zhang
86. Can "as-forged" material be certified to NACE MR0175
Question:
Often my company is asked by customers to certify our forgings to NACE MR0175. It
is my understanding from them that our competition including imports certifies to
MR0175 without normalizing and consequently we are pressured to do the same. We
have three presses two are fed by gas-fired furnaces and one is with induction
heaters. The gas heat forgings are typically heated to 2300 to 2350°F and forged on
a 900T or 3500T open die press in a tooling pot then still air cooled to ambient. The
forgings heated by induction are heated to similar temperatures but only a portion of a
bar and the flange end is forged close to shape then air cooled in still air. Customers
can order these forgings in the "as forged" or "normalized" condition per SA105. My
question is do we have to normalize the forgings coming from either forging process in
order to certify to NACE MR0175 The problem is interpretation of NACE
MR0175/ISO 15156-2:2003E page 17 Annex A Paragraph A.2.1.2. The heat-
treated condition "hot-rolled" is not clearly understood and competitors with similar
processes interpret that if the entire raw material piece prior to forge lets call it a mult
is taken to 2300 to 2350°F prior to forge that this satisfies the "hot-rolled" definition.
We have contended that our products need to be subsequently followed with a
normalizing cycle after being fully cooled to ambient in order to be certified to NACE
and that neither of the forging processes listed above satisfies the definition of "hot-
rolled" process.
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slide 135: Charlie Chong/ Fion Zhang
Hot-forged material does not meet the intent of NACE MR0175/ISO 15156-2
A.2.1.2a.
An exception to this statement is given in A.2.1.3a.
Other hot-forged materials would have to be treated according to one of the
five other heat-treatment conditions described in Paragraph A.2.1.2 to comply
with this standard.
As a consequence ASTM A 105 material is acceptable in the "as-forged"
condition not because it is equivalent to a "hot rolled" condition in A.2.1.2 but
because it is a permitted exception in A.2.1.3.a.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A.2.1.2
Reference: ISO 15156 Maintenance Panel Inquiry 2005-25
https://oilandgascorrosion.com/faqs/
slide 136: Charlie Chong/ Fion Zhang
87. Is ASTM A105 Class 150 flange in the non-normalized is acceptable
to NACE MR0175
Question:
Would a forged ASTM A105 Class 150 flange in the non-normalized
condition be in accordance with NACE MR0175 and NACE MR0103
Answer:
The ISO 15156 Maintenance Panel can only answer for NACE MR0175/ISO
15156 not for NACE MR0103.
AS FORGED is not an acceptable condition in A.2.1.2. Both requirements of
A.2.1.2. and A.2.1.3 of Part 2 must be fulfilled for ASTM A 105 flanges to meet
NACE MR0175/ISO 15156.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A.2.1.2
Reference: ISO 15156 Maintenance Panel Inquiry 2009-08
https://oilandgascorrosion.com/faqs/
slide 137: Charlie Chong/ Fion Zhang
88. In NACE MR0175 are tubulars with SMYS below 52ksi exempt of
hardness testing
Question:
Per A.2.1.4 "Tubular products with an SMYS not exceeding 360 MPa 52ksi
and listed in Table A.2 are acceptable in the as-welded condition. For these
products hardness testing of welding procedures may be waived if agreed by
the equipment user". Is a correct interpretation that all hardness testing is
being waived for tubular products with an SMYS not exceeding 52ksi in the
as-welded condition if as agreed by the equipment user
Answer:
No tubular products listed in Table A.2 with an SMYS not exceeding 360 MPa
52 ksi are acceptable in the as welded condition. For these products
hardness testing OF WELDING PROCEDURES may be waived if agreed by
the equipment user.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A.2.1.4
Reference: ISO 15156 Maintenance Panel Inquiry 2006-01Q1
https://oilandgascorrosion.com/faqs/
slide 138: Charlie Chong/ Fion Zhang
NOTE:
Hardness testing on WPS could be
waived with hardness testing on
parent metal remains
https://oilandgascorrosion.com/faqs/
slide 139: Charlie Chong/ Fion Zhang
89. For NACE MR0175 compliance of carbon steels whats the
maximum hardness after PWHT
Question:
A.2.1.4 Welding Paragraph 6 states: "Carbon steel and low-alloy steel weldments that
do not comply with other paragraphs of this subclause shall be stress-relieved at a
minimum temperature of 620 °C 1 150 °F after welding. The maximum weld zone
hardness determined in accordance with 7.3 shall be 250 HV or subject to the
restrictions described in 7.3.3 22 HRC." This particular paragraph does not refer to
Table A.1 Maximum acceptable hardness values for carbon steel carbon-manganese
steel and low-alloy steel welds which states that weld cap hardness can be 275 HV
with limitations. Could NACE please clarify if Table A.1 should or should not be
applicable for stress-relieved weldments. Which hardness value 250 HV or 275 HV
shall be applicable for weld cap hardness of stress-relieved weldments
Answer
Table A.1 gives maximum acceptable values for carbon steel carbon-manganese
steel and low alloy steel weldments. It is applicable to welds whether they have been
post weld heat treated or not.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A.2.1.4
Reference: ISO 15156 Maintenance Panel Inquiry 2011-01
https://oilandgascorrosion.com/faqs/
slide 140: Charlie Chong/ Fion Zhang
90. Weldment with Nickel greater than 1 does NACE MR0175 / ISO
15156-2 subclause A.2.1.4 say they are not acceptable
Question:
ISO 15156-2 subclause A2.1.4 Welding has the following two paragraphs:
"Carbon steel and low-alloy steel weldments that do not comply with other
paragraphs of this subclause shall be stress-relieved at a minimum
temperature of 620 °C 1150 °F after welding. The maximum weld zone
hardness determined in accordance with 7.3 shall be 250 HV or subject to
the restrictions described in 7.3.3 22 HRC". "Welding consumables and
procedures that produce a deposit containing more than 1 mass fraction
nickel are acceptable after successful weld SSC qualification by testing in
accordance with Annex B". Based on this I interpret the requirements as
follows: If there are weldments with Ni contents greater than 1 mass fraction
they can be accepted if the weld procedures are successfully tested to SSC
qualification in accordance with Annex B. Alternately weldments with Ni
contents greater than 1 mass fraction shall be acceptable if stress-relieved
at a minimum temperature of 620 °C 1150 °F after welding. The maximum
weld zone hardness shall be 250HV or 22 HRC in that case. Please can you
confirm the interpretation.
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slide 141: Charlie Chong/ Fion Zhang
Answer:
The intent of the next to last paragraph in A.2.1.4 15156-2 Annex A dealing
with the 620C 1150F SR option does not negate the requirement in the
following paragraph which requires SSC qualification testing regardless of SR
if the weld deposit is 1 Ni.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A.2.1.4
Reference: ISO 15156 Maintenance Panel Inquiry 2013-07
https://oilandgascorrosion.com/faqs/
slide 142: Charlie Chong/ Fion Zhang
The intent of the next to last paragraph
in A.2.1.4 15156-2 Annex A dealing
with the 620C 1150F SR option does
not negate the requirement in the
following paragraph which requires
SSC qualification testing regardless of
SR if the weld deposit is 1 Ni.
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slide 143: Charlie Chong/ Fion Zhang
91. Does NACE MR0175 require PWHT of overlay weld inconel 625
Question:
We have weld overlays Inconel 625 filler metal with SAW process applied to
low-alloy ferritic steel valves ASME/ASTM A 352 Gr LCC. The steel valve is
used on wet gas wellhead production platform with operating temperatures at
93°C operating pressure of 145 bar with vapor fraction of H2S 177 kg-mol/h
and CO2 877 kg-mol/h. Hardness tests were performed on the as-welded
condition. The results achieved were well below the 250 HV criteria of Table
A.1 of NACE MR0175/ISO 15156-2. Since the hardness results complied with
the requirements of Table A.1 of NACE MR0175/ISO 15156-2 we believe and
understand that the valve does not require postweld heat treatment after the
weld overlay. Having met the hardness criteria after overlay we believe that
we met the requirements of the following paragraphs of NACE MR0175/ISO
15156-2: -Paragraph A.2.1.5 and -Paragraph A.2.1.4
Question: Is our interpretation of Paragraphs A.2.1.5 and A.2.1.4 of NACE
MR0175/ISO 15156-2 correct based on the above-stated specific application
and conditions and that the valves overlayed with Inconel 625 consumables
do not require postweld heat treatment
https://oilandgascorrosion.com/faqs/
slide 144: Charlie Chong/ Fion Zhang
Answer:
Paragraph A.2.1.4 states in the third sentence:
“As welded carbon steels carbon manganese steels and low-alloy steels that
comply with the hardness requirements of Table A.1 do not require postweld
heat treatment.” Paragraph A.2.1.5 states: “Overlays applied by thermal
processes such as welding . . . are acceptable if they comply with one of the
following: a The heat-treated condition of the substrate is unchanged i.e. it
does not exceed the lower critical temperature during application of the
overlay. b The maximum hardness and final heat-treated condition of the
base metal substrate comply with A.2.1.2 and in the case of welded overlays
A.2.1.4.
Therefore your interpretation is correct. Provided your weld procedure
qualification complies with the hardness requirements in A.2.1.4 and A.2.1.5
no postweld heat treatment is required.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A.2.1.4 and
A.2.1.5
Reference: ISO 15156 Maintenance Panel Inquiry 2004-11
https://oilandgascorrosion.com/faqs/
slide 145: Charlie Chong/ Fion Zhang
Weld Overlays
https://oilandgascorrosion.com/faqs/
slide 146: Charlie Chong/ Fion Zhang
Weld Overlays
https://oilandgascorrosion.com/faqs/
slide 147: Charlie Chong/ Fion Zhang
Weld Overlays
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slide 148: Charlie Chong/ Fion Zhang
92. NACE MR0175 and surface treatments to prevent SSC
Question:
ANSI/NACE MR0175/ISO 15156-2 Section A.2.1.5 Surface Treatments
Overlays Plating Coatings Linings etc. This section states that metallic
coatings such as electroless nickel plating are not acceptable for preventing
SSC. It was my understanding that the qualification of a plated part was
dependent on the base metal. If the base metal is in conformance with
MR0175 then the part can be qualified regardless of what plating or coating
may be applied. Is my understanding correct
Answer:
The application and use of metallic plating that does not affect the ISO 15156
compliant base material is not prohibited. No metallic platings are listed as
acceptable or unacceptable in ISO 15156 but the use of any surface
treatments to prevent SSC is not acceptable.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A.2.1.5
Reference: ISO 15156 Maintenance Panel Inquiry 2011-13
https://oilandgascorrosion.com/faqs/
slide 149: Charlie Chong/ Fion Zhang
93. For NACE MR0175 compliant products is Carburizing an acceptable
surface treatment process
Q1: For NACE MR0175 compliant products is Carburizing an acceptable surface
treatment process
A1 Carburizing is not currently permitted in ISO 15156 except in conjunction with the
permitted exclusions in Table 1 of ISO 15156-2. These exclusions are associated with
specific equipment that is loaded in compression and equipment that is outside the
scope of ISO 15156.
Q2: If Carburizing is not considered the same as Nitriding in paragraph A. 2.1.5 is it
acceptable to have carburized surface treatment where the surface hardness will be
well over HRC 22 hardness but the core to meet the maximum average hardness of
22 HRC
A2: Carburizing is not permitted regardless of core hardness except as noted in Q1.
Q3: If Carburizing is acceptable surface treatment method can the max hardness
HRC 22 and Nickel content max 1 of the core of carburized part be allowed to be
higher than what NACE MR0175 allows
A3: Not applicable.
This question is in relation to NACE MR0175/ISO 15156-3 Annex A.1.5.1
Reference: ISO 15156 Maintenance Panel Inquiry 2013-04
https://oilandgascorrosion.com/faqs/
slide 150: Charlie Chong/ Fion Zhang
94. Does NACE MR0175 accepts 26HRC for temporary pipework
Question:
We need a clarification on MR0175/ISO 15156 Part 2 Annex A. We are a
manufacturer of temporary pipe work flowlines etc. for sour gas service in
well testing and process use in a surface application. As such we believe
Paragraphs A.2.1 through A.2.4 and Table A.1 with a hardness limit of 22
HRC are applicable in these circumstances. However pipe suppliers in this
region tell us that 26 HRC is acceptable in such applications. I believe the 26
HRC limit is only applicable to material used in a downhole application as in
Paragraph A.2.2.3 etc. i.e. not a surface application and that this is in error
in terms of our usage.
https://oilandgascorrosion.com/faqs/
slide 151: Charlie Chong/ Fion Zhang
Answer:
ISO 15156-2 A.2.2.1 indicates that carbon and low alloy steels for use in any
product form must comply with the requirements of A.2.1 which include the
hardness requirement of maximum 22 HRC for the parent material.
Exceptions to this rule are named specifically in other paragraphs of Annex A.
Welds in such materials shall comply with the requirements of A.2.1.4 that
also refers to Table A.1 that sets hardness requirements for welds.
Sub-clause A.2.2.2 provides examples of materials that can comply with
A.2.1 including some examples of tubular products in Table A.2.
Sub-clause A.2.2.3 addresses downhole components only.
The standard allows materials such as AISI 4130 to be qualified at higher
hardness than 22 HRC for possible use as pipe in sour service by laboratory
testing in accordance with Annex B and Table B.1 or on the basis of field
experience as described in ISO 15156-1 8.2. Welds must be shown to
comply with the requirements of Paragraph 7.3.3.4.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A.2.2.1
A.2.2.2 and A.2.2.3
Reference: ISO 15156 Maintenance Panel Inquiry 2005-23
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slide 152: Charlie Chong/ Fion Zhang
A.2.2.3.2 Tubulars and tubular components made of Cr-Mo low-alloy
steels UNS G41XX0 formerly
AISI 41XX and modifications if quenched and tempered in the tubular form
are acceptable if their hardness does not exceed 30 HRC and they have
SMYS grades of 690 MPa 100 ksi 720 MPa 105 ksi and 760 MPa 110
ksi. The maximum yield strength for each grade shall be no more than 103
Mpa 15 ksi higher than the SMYS. SSC resistance shall be demonstrated by
testing each test batch and shall comply with B.1 using the UT test.
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slide 153: Charlie Chong/ Fion Zhang
95. What are the NACE MR0175 requirements for risers choke kill and
booster lines
Question:
We have a request for interpretation of item A.2.2.3.3 of ISO 15156-2. It
states that “tubulars and tubular components made of Cr-Mo low alloy steels
UNS G41XX0 formerly AISI 41XX and modifications if quenched and
tempered in the tubular form are acceptable if the hardness does not exceed
26 HRC. These products should be qualified by SSC testing in accordance
with B.1 using the UT test.” We use AISI 4130 tubes in the quenched and
tempered condition for drilling riser P-lines choke kill and booster lines and
have at present a hardness limit of HRC 22. The relaxation of above
hardness requirement to HRC 26 would be helpful in production of the pipes
as well as weldments.
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slide 154: Charlie Chong/ Fion Zhang
Answer:
Paragraph A.2.2.3.3 of ISO 15156-2 is applicable to downhole casing tubing
and tubular components used in region 3 of the diagram in Paragraph 7.2.
Materials for P-lines in drilling risers are not included in Paragraph A.2.2.3.3.
Materials for P-lines used in Region 3 are hardness limited to HRC 22. The
point you raise concerning Inquiry 2005-23 is valid since testing according to
Table B.1 in Annex B is one of the accepted qualification methods. Testing
can be used to qualify any material/application including 4130/P-lines in
drilling risers provided it is performed according to ISO 15156 requirements.
This question is in relation to NACE MR0175/ISO 15156-2 Annex A.2.2.2 and
A.2.2.3
Reference: ISO 15156 Maintenance Panel Inquiry 2010-04
Note:
A.2.2.3 Downhole casing tubing and tubular components
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slide 155: Charlie Chong/ Fion Zhang
A.2.2 Application to product forms
A.2.2.1 General
Except as modified below the general requirements of A.2.1 shall apply
to all product forms.
A.2.2.2 Pipe plate and fittings
A.2.2.3 Downhole casing tubing and tubular components
A.2.2.4 Bolting and fasteners
A.2.1.2 Parent metal composition heat treatment and hardness
Carbon and low-alloy steels are acceptable at 22 HRC maximum hardness
provided they contain less than 1 mass fraction
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slide 156: Charlie Chong/ Fion Zhang
A.2.3 Application to equipment
A.2.3.1 General
A.2.3.2 Drilling blowout preventers
A.2.3.3 Compressors and pumps
slide 157: Charlie Chong/ Fion Zhang
ISO 15156-2:2015E
A.2.1.2 Parent metal composition heat treatment and hardness
Carbon and low-alloy steels are acceptable at 22 HRC maximum hardness provided
they contain less than 1 mass fraction nickel are not free-machining steels and are
used in one of the following heat treatment
conditions:
a hot-rolled carbon steels only
b annealed
c normalized
d normalized and tempered
e normalized austenitized quenched and tempered
f austenitized quenched and tempered.
A.2.1.3 Carbon steels acceptable with revised or additional restrictions
In addition to the restrictions of A.2.1.2 some carbon steels are acceptable subject to
the following revised or additional restrictions.
a Forgings produced in accordance with ASTM A105 are acceptable if the hardness
does not exceed 187 HBW.
b Wrought pipe fittings to ASTM A234 grades WPB and WPC are acceptable if the
hardness does not exceed 197 HBW.
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slide 158: Charlie Chong/ Fion Zhang
A.2.1.2 Parent metal composition heat treatment and hardness
Carbon and low-alloy steels are acceptable at 22 HRC maximum hardness
provided they contain less than 1 mass fraction nickel are not free-
machining steels and are used in one of the following heat treatment
conditions:
a hot-rolled carbon steels only
b annealed
c normalized
d normalized and tempered
e normalized austenitized quenched and tempered
f austenitized quenched and tempered.
Does it mean ALL Carbon and low-alloy steels are acceptable satisfying the
above conditions With the exception stated for A.2.1.3 on Forgings
produced in accordance with ASTM A105 and Wrought pipe fittings to ASTM
A234 grades WPB and WPC both with lower maximum hardness limitations .
It could be more exception
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slide 159: Charlie Chong/ Fion Zhang
Carbon and low-alloy steels
are acceptable at 22 HRC
maximum hardness
provided they contain less
than 1 mass fraction
nickel are not free-
machining steels and are
used in one of the specified
heat treatment
conditions.
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slide 160: Charlie Chong/ Fion Zhang
Kobel Steel 神户钢铁
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slide 162: Charlie Chong/ Fion Zhang
96. What does NACE MR0175 require from dissimilar welds without
filler
Question:
My employer manufactures pressure sensing devices that have a very small sensing
diaphragm welded to a threaded port. I am hoping you can provide some clarification
regarding welding of dissimilar metals. I am employing the material hardness limits for
specific materials from Annex A of ISO 15156-3 in conjunction with the weld survey
locations specified in 7.3.3.3 of ISO 15156-2. I believe the hardness requirements are
clearly interpreted if welding dissimilar metals by use of a third weld-filler metal.
Hardness requirements can be clearly applied to each of the weld survey locations for
all three involved parent materials. However I do not know how to apply the hardness
requirements when two materials are welded directly together without the use of a
third weld-filler metal. 1. If the two materials have different hardness limits what is the
hardness requirement for the weld survey locations within the weld metal region non
parent material nor HAZ regions 2. Is the hardness limit governed by the higher of
the two material limits or the lower of the two 3. Can you tell me where I can find
clarification in these standards or where I can direct my question 4. On an unrelated
note I would like to suggest a minor improvement to table A.1 of ISO 15156-3 Annex
A. In T able A.6 Note-B defines the table applicable to “…diaphragms pressure
measuring devices and pressure seals.” Table A.1 would be improved if “A.6” was
specified in the first column Austenitic stainless steel for the row designated for
“Diaphragms pressure measuring devices and pressure seals”.
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Answer:
1. The hardness requirements for each material shall be met for both the
base metal and HAZ. The standard does not specify requirements for the
fusion line hardness between two dissimilar metals with different maximum
hardness requirements. Qualification by successful laboratory testing in
accordance with Annex B of ISO 15156-3 is required. Qualification based on
satisfactory field experience is also acceptable. Such qualification shall
comply with ISO 15156-1.
2. See answer to point 1
3. See answer to point 1.
4. This is an editorial improvement and this will be changed.
This question is in relation to NACE MR0175/ISO 15156-3 Annex A
Reference: ISO 15156 Maintenance Panel Inquiry 2014-04
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slide 164: Charlie Chong/ Fion Zhang
97. Flame spraying is it allowed in NACE MR0175
Question:
We have some 316 stainless steel housings with a large through bore
machined. Inadvertently this bore was machined oversize. We would like to
flame spray build up the surface with 316 or 316L stainless material and
remachine to size. As we understand the standard 316 and 316L stainless
are both included in a lengthy list of materials accepted for direct exposure to
sour gas. As we intend to apply stainless to stainless for the purpose of
remachining to dimension and not as a corrosion-inhibiting coating would this
process be acceptable and compliant with the NACE Standard MR0175/ISO
15156
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slide 165: Charlie Chong/ Fion Zhang
Answer:
1.0 Flame spraying as a coating for corrosion resistance over a base material
that is resistant to sulfide stress cracking is acceptable within the
requirements of NACE MR0175/ISO15156 Part 2 Paragraph A.2.1.5 when
applied over carbon steels and of Part 3 Paragraph A.1.5.1. In the case of
your inquiry the 316 or 316L base materials are acceptable coating
substrates if they conform to the metallurgical requirements of Part 3 Table
A.2 and are used within the environmental restrictions of this table for any
equipment.
2.0 If this application of flame spray is for the replacement of material that will
be load bearing of tensile stresses then the inquiry is not currently addressed
by NACE MR0175/ISO15156. NACE/ISO have not been balloted with data to
demonstrate that the 316 SS or 316L SS deposited flame spray coating has
the same cracking resistance as the materials referenced in Part 3 Table A.2
which are assumed to be in the cast or wrought conditions.
This question is in relation to NACE MR0175/ISO 15156-3 Annex A.1.5.1
Reference: ISO 15156 Maintenance Panel Inquiry 2005-01
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slide 166: Charlie Chong/ Fion Zhang
ISO 15156-2:2015E
A.2.1.5 Surface treatments overlays plating coatings linings etc.
NOTE The composition and cracking resistance of overlays are addressed in
ISO 15156-3.
ISO 15156-3:2015E
A.13 Cladding overlays and wear-resistant alloys
A.13.1 Corrosion-resistant claddings linings and overlays
The materials listed and defined in A.2 to A.11 can be used as corrosion-
resistant claddings linings or as weld overlay materials.
The overlay material shall be as materials
listed and defined in A.2 to A.11
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slide 167: Charlie Chong/ Fion Zhang
98. For NACE MR0175 compliant products is Carburizing is an
acceptable surface treatment process
Carburizing is not currently permitted in ISO 15156 except in conjunction with
the permitted exclusions in Table 1 of ISO 15156-2. These exclusions are
associated with specific equipment that is loaded in compression and
equipment that is outside the scope of ISO 15156.
This question is in relation to NACE MR0175/ISO 15156-3 Annex A.1.5.1
Reference: ISO 15156 Maintenance Panel Inquiry 2013-04Q1
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slide 168: Charlie Chong/ Fion Zhang
99. If Carburizing is not considered the same as Nitriding in paragraph
A. 2.1.5 is it acceptable to have carburized surface treatment where the
surface hardness will be well over HRC 22 hardness but the core to
meet the maximum average hardness of 22 HRC
Carburizing is not permitted regardless of core hardness except as noted in
Q1.
This question is in relation to NACE MR0175/ISO 15156-3 Annex A.1.5.1
Reference: ISO 15156 Maintenance Panel Inquiry 2013-04Q2
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slide 169: Charlie Chong/ Fion Zhang
100. If Carburizing is acceptable surface treatment method can the max
hardness HRC 22 and Nickel content max 1 of the core of
carburized part be allowed to be higher than what NACE MR0175
allows
Not applicable.
This question is in relation to NACE MR0175/ISO 15156-3 Annex A.1.5.1
Reference: ISO 15156 Maintenance Panel Inquiry 2013-04Q3
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slide 170: Charlie Chong/ Fion Zhang