Pipe-Manufacturing: Pipe-Manufacturing A glance at Pipe Manufacturing Industry….. Contents: Contents This will be discussed under following Major headings:- Types of Pipe Manufacturing Process. Manufacturing Parameters. Inspection-Raw material inspection. Requirement & End usage. Production,Quality & End Customers. Types of Pipe Manufacturing Process: Types of Pipe Manufacturing Process HSAW PIPES(Helical Submerged arc Welded Pipes). LSAW PIPES. ERW PIPES. SEAMLESS PIPES. HSAW PIPES: HSAW PIPES Manufacturing Process for Seamless Pipes: Manufacturing Process for Seamless Pipes Seamless pipe: Seamless pipe ERW PIPES: ERW PIPES Raw material required for Manufacturing Seamless,ERW,LSAW,HSAW PIPES: Raw material required for Manufacturing Seamless,ERW,LSAW,HSAW PIPES Steel round billets are required to manufacture Seamless pipes.Billets are procured both from Indigenous Suppliers & from abroad. HR Coils are required to manufacture ERW pipes,HSAW pipes which are Sourced from POSCO,ESSAR,TATA,JSW,HADEED & Other International & domestic mills from Europe,Canada & Far East of China. For LSAW pipes HR-Plates are required ,source from domestic & International-Mills. Difference betn SeamlessPipes,ERW & SAW pipes:
Difference betn SeamlessPipes,ERW & SAW pipes In Seamless pipe,there are no welding or joints & is manufactured from solid round billets.It is mainly used for High-Pressure applications such as Oil & Gas Exploration & Drilling,Oil & Gas Transportation,Hydrocarbon Industries & Refineries,Air & Hydraulic Cylinders,Bearings,Boilers,Automobiles etc ERW pipes are welded longitudinally manufactured from Strip/Coil & can be manufactured up to 20-inches mainly used for low/medium pressure applications such as
of Water/Oil. SAW Pipes are either longitudinally or Spiral welded manufactured from Plate & Coil ,can be manufactured up to 100-inches OD.It is used for transportation of large volume of liquid/gases. Seamless Pipes cannot be substituted for others.Only ERW & SAW Pipes can be substituted.
Does Pipe industry forsee any threat from substitution of Other types of Pipes: Does Pipe industry forsee any threat from substitution of Other types of Pipes Seamless Pipe is a high-end Product & used only in the high Pressure application areas & Other Steel-Pipes Viz. Spiral & ERW Pipes Cannot be used as a substitute .Hence Seamless Pipe industries has a bright future ahead. Technologies for Production of Seamless & ERW Pipes: Technologies for Production of Seamless & ERW Pipes “CPE” Technology” used for Seamless Pipes & Tubes Production up to 7-inches OD is the world renowned Technology. “Plug Mill” Technology used for Higher Dia. Seamless Pipes & Tubes Production from 7-inches to 14-inches,is the most reliable technology,in higher dia. Segment. High frequency Induction Welding Technology is used for ERW Pipes &Tubes upto 21-inchesOD. Major Customers of Seamless Pipes,ERW Pipes: Major Customers of Seamless Pipes,ERW Pipes Oil & Gas Sectors Companies:- ONGC,Oil India,GAIL etc. Automation Sector Companies:-Bajaj Auto,LML,M&M,TELCO,etc Bearing Industry-: FAG,NEI,etc . Boiler & Heat Exchanger( ABB,BHEL,ISGEC,Thermax etc). Indian Railways etc. Export Segment viz. USA,Europe,Middle -East & Far East Countries. Hydraulic-Cylinders –Salzgitter Hydraulic Ltd. PipeMills registered Vendors with domestic Oil & Gas Players,refineries: PipeMills registered Vendors with domestic Oil & Gas Players,refineries ONGC,OIL,GAIL,RIL,Indraprastha Gas,Cairn-energy,Mahanagar Gas Ltd,British Gas etc,KOC,Saudi-aramco,KNPC,PETRONAS,SHELL,EXXON . Exploration & Production of Crude Oil is going up,this will lead to increasing demand of Seamless Pipes mainly for Oil Companies & Tabular Goods(OCTG).Globally Exploration & Production activities which will lead to increase in demand of Seamless Pipe World-over. LSAW-Pipe Manufacturing: LSAW-Pipe Manufacturing Edge milling Machine. Roll bending machine. Post bending machine. Continous root welding machine. Internal welding station. External welding station. X-ray Station. Hydrotester . End facing machine. Expanded area External welding station. Ultrasonic testing station Picture depicting LSAW-Pipe Manufacturing: Picture depicting LSAW-Pipe Manufacturing Edge milling machine: Edge milling machine b)Roll bending machine: b)Roll bending machine The forming in the pipe mill is accomplished through the use of a Hydraulic 3-Roll bending machine type with prestressed top roll. With only 2-3 passes a plate is bent into an open seam pipe. c)Post bending machine: c)Post bending machine In the post bending machine,which works by an innovative roll/die process the remaining flat ends are formed to the proper pipe diameter. Continous welding machine: Continous welding machine The finished formed slot pipe is finally adjusted & tack –welded with a continous root in the tack-welding machine under gas shielded arc.The root weld also serves as backing for the inside welding of the pipe. Internal welding station: Internal welding station The internal welding station consists of a height-adjustable welding boom including SAW equipment.The pipe moves on a pipe transport carriage.A video system helps the operator to control the process. External welding station: External welding station The external welding station consists of a pipe transport carriage & outside heigt -adjustable welding boom equipped with SAW equipment.The pipe is transported through the station on the carriage.Following the weld seam is extremely visually inspected.The end taps are removed & the overstand of welding on both pipe ends is manually smoothed following the test procedure. Pic.-External Welding Station: Pic .-External Welding Station X-ray Station: X-ray Station In the second X-ray station both pipe ends of the weld seam are filmed accprding to the required standard.Eventual suspected defects observed in the ultrasonic defects observed in the ultrasonic station are also filmed. The equipment can also be extended for a real-time X-ray over the full pipe length.Afterwards a visual inspection covers the complete pipe surface in order to detect & remove any visual defects. Pic-Showing LSAW Pipes: Pic -Showing LSAW Pipes Pic-For XRAY-Station: Pic -For XRAY-Station Hydrotester: Hydrotester The hydrostatic pipe tester,necessary for all quality standards,tests each pipe by internal water pressure.Each length of pipe must withstand without leakage a hydrostatic test to at least the pressure specified in the standards. Pic-For Hydrostation: Pic -For Hydrostation End facing machine: End facing machine The pipe-end bevelling machine chamfers simultaneously both ends to the requirement. By bevelling both ends simultaneously their parallelism is guaranteed.The bevel is concentric with the pipe inside the diameter. Pic-For End facing Station: Pic -For End facing Station Internal welding station: Internal welding station The internal welding station consists of a height-adjustable welding boom including SAW equipment.The pipe moves on a pipe transport carriage.A video system helps the operator to control the process. Pic.-For Internal Welding Station: Pic .-For Internal Welding Station Expanded area: Expanded area The pre-washing station serves to remove all remaining flux,slags & milling scale by water. In the mechanical expander the pipe is sized to tighter tolerances of diameter & straightened according to any international standards or Customer requirements.Beside the sizing process for closer tolerances the expanding process increases the material yield of about 5-8%. The post-washing station removes the expander lubrication oil from the internal pipe body by high water pressure. External welding station: External welding station The external welding station consists of a pipe transport carriage & outside height-adjustable welding boom equipped with SAW equipment.The pipe is transported through the station on the carriage. Following the weld seam is extremely visually inspected.The end taps are removed & the overstand of welding on both pipe ends is manually smoothed for the following testingprocedure . At the visual inside weld inspection,the pipe is cleaned from flux & slag & visually inspected by a video camera or an operator(depending on the pipe diameter). Ultrasonic testing station: Ultrasonic testing station In the first ultrasonic testing station the weld seam is tested for any defects.Satisfactory pipes are transported to the pre-washing station while pipes with defects are diverted to the repair x-ray station where the defects are documented and repaired. Pic –For Ultrasonic test Station: Pic –For Ultrasonic test Station API Pipe Grades: API Pipe Grades Different API-Grades:- API Pipe Grades: API Pipe Grades Grade B, X42, X52, X60, X65, X70, X80 And Two Product Specification Levels API Pipe Grades: API Pipe Grades Grade B, X42, X52, X60, X65, X70, X80 And Two Product Specification Levels PSL 1 and PSL 2 Slide 39: API Grade X60, PSL 2 Yield Strength Range 60.2 – 81.9 ksi 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 API Grade X65, PSL 2 Yield Strength Range 65.3 – 87 ksi Yield Strength in ksi API Grade X70, PSL 2 Yield Strength Range 70.3 – 92.1 ksi Historically, it has been a common practice to apply dual-grade markings at the lower end of the grade spectrum : Historically, it has been a common practice to apply dual-grade markings at the lower end of the grade spectrum The most common dual grade product has always been Grade B/X42: The most common dual grade product has always been Grade B/X42 Other common dual-grade items are: -X42/X46 -B/X42/X46 -X42/X52 Slide 42: - Pipe manufactured as Grade X60 (415) or higher shall not be substituted for pipe ordered as Grade X52 (360), or a lower grade, without the purchaser's approval. API Specification 5L Provides Only Minimal Guidelines regarding dual markings for Line Pipe: - API Spec 5L, Annex N specifically allows marking pipe with comparable specifications. This allows pipe to have API markings as well as CSA or ISO designations In the last few years, pipe mills have seen an increased number of requests for application of dual-grade markings in upper grades. - X60 / X65 -X65 / X70 - X60 / X65 / X70 -X70 / X80 : In the last few years, pipe mills have seen an increased number of requests for application of dual-grade markings in upper grades. - X60 / X65 -X65 / X70 - X60 / X65 / X70 -X70 / X80 Slide 44: API Grade X60, PSL 1 Yield Strength Minimum 60.2 (no maximum for PSL 1) 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 API Grade X65, PSL 1 Yield Strength Minimum 65.3 (no maximum for PSL 1) Yield Strength in ksi API Grade X70, PSL 2 Yield Strength Range 70.3 – 92.1 ksi API Grade X80, PSL 2 Yield Strength Range 80.5 – 102.3 ksi 96 98 100 102 104 API Grade X52, PSL 1 Yield Strength Minimum 52.6 (no maximum for PSL 1) X52 PSL 1, X60 PSL1, X65 PSL 1, X70 PSL 2, X80 PSL 2: X52 PSL 1, X60 PSL1, X65 PSL 1, X70 PSL 2, X80 PSL 2 There have been reports of pipe being stenciled and certified as follows: Welding Procedures shall be qualified within the following grade ranges: < X42 X46, X52, X56 (including intermediate grades) For X60 & above, each grade is qualified individually: Welding Procedures shall be qualified within the following grade ranges: < X42 X46, X52, X56 (including intermediate grades) For X60 & above, each grade is qualified individually API 1104 for Field Welding of Line Pipe contains the following restrictions on welding procedure qualification: Slide 47: One pipeline operator reported that they were laying a line of X65 PSL 2 pipe. They were using X65 / X70 dual grade pipe in the line. They were audited by the pipeline regulatory agency (PHMSA) and all of their welding documentation referenced qualification of API Grade X65, PSL 2. Since the pipe was X65 / X70 and each grade is required to be qualified separately, the auditor would not accept the X65 documentation. Slide 48: Proposal Issued for Vote to the API Membership for requirements to be added to API Spec 5L: Slide 49: The results of the ballot were surprising. Overall, the votes were for acceptance of the new requirement. However, as expected, there were a number of negative votes. The biggest objection was that the current proposal restricts dual-grading of X42 / X52, which has been a common industry practice. API requires that negative ballots must be resolved before the item can go forward. Slide 50: The work on this item is currently on-going. A new edition of API Specification 5L will probably be issued early 2011. It is the intent of the work group to have this item finalized and ready for publication in the next edition of the Specification. Before that can happen, all negative votes have to be resolved and the exact wording of the requirement will need to be finalized. The final version will be reviewed by members of the API 1104 group as well as the API Quality group to assure compliance with those requirements. Slide 51: Marking of Pipe to Multiple Grades: Marking of pipe to multiple grades is permitted only by agreement between the purchaser and the manufacturer within the following guidelines: - Pipe may have multiple markings within the following grade ranges: < X42 X46, X52, X56 (including intermediate grades) For X60 & above, marking of multiple grades is prohibited - The manufacturer is responsible to assure that the pipe conforms to all requirements of each of the certified grades. This allows pipe to be used as any of the grades individually. - Pipe shall be marked to only one PSL level. - Where pipe is marked to multiple grades, a single certification document shall be issued referencing the grade combination as marked on the pipe. The certification document may contain a specific statement that pipe conforms to each grade individually. - Pipe shall only be re-graded and re-marked under the manufacturer’s control. Certificates for re-graded pipe may only be issued by the pipe manufacturer. Slide 52: While designing the pipeline, following needs to be considered. The type of material and properties, Manufacturing methods, Time required for pipe laying, Tolerance controls on dimensions of pipes, Welding processes and techniques, Inspection methods and techniques, Acceptance limits of defects, etc. SPECIFICATION FOR LINE PIPE: SPECIFICATION FOR LINE PIPE API 5L/2007 ISO 3183/2007 NACE MR 0175/ ISO15156 TYPES OF PIPE: TYPES OF PIPE SEAMLESS PIPE CONTINUOS WELDED PIPE ELECTRIC WELDED PIPE - PSL 1 Electric Welded Pipe: For grades higher than X42, heat treatment of weld seam and entire HAZ - PSL 2 Electric Welded Pipe: Welding with a minimum welder frequency of 100 kHz. LONGTITUDINAL SEAM SUBMERGED-ARC WELDED PIPE One longitudinal seam produced by automatic submerged –arc welding process GAS METAL-ARC WELDED PIPE One longitudinal seam produced by continuous gas metal arc welding process HELICAL SEAM SUBMERGED ARC WELDED PIPE Making of one helical seam PSL 2: PSL 2 PSL 2 has mandatory requirements for Carbon equivalent , Notch toughness, Max. yield strength and Max. tensile strength MATERIAL REQUIREMENTS : MATERIAL REQUIREMENTS Chemical Composition Different grades of steel must contain certain amount of iron and alloying elements (Mn, Cu, Ni, Si, Al etc.) to attain desired mechanical properties. Mechanical Properties - For cold expanded pipe, ratio of body yield strength and body UTS shall not exceed 0.90. -The YS shall be the tensile stress required to produce a total elongation of 0.5% of the gage length as determined by extensometer. CARBON EQUIVALENT FOR PSL 2: CARBON EQUIVALENT FOR PSL 2 When Carbon content <= 0.12%, CE= C+Si /30+Mn/20+Cu/20+Ni/60+Cr/20+Mo/15+V/10+5B Max. CE =0.25% When Carbon content >= 0.12%, CE= C+Mn /6+( Cr+Mo+V )/5+( Ni+Cu )/15 Max. CE =0.43% TYPICAL COMPOSITION AND MECH. PROPERTIES (PSL2): TYPICAL COMPOSITION AND MECH. PROPERTIES (PSL2) Composition: GRADE C (Wt%) max Mn (Wt%) max P (Wt%) max S (Wt%) Max Ti (Wt%) Max X46, X52 0.22 1.40 0.025 0.015 0.04 X65 0.22 1.45 0.025 0.015 0.06 X70 0.22 1.65 0.025 0.015 0.06 Mechanical Properties: GRADE YS (psi), min YS (psi), max UTS (psi), min UTS (psi), max X52 52000 77000 66000 110000 X70 70000 90000 82000 110000 MATERIALS USED : MATERIALS USED Traditionally, C- Mn steels similar to API 5L grades- X46, X52, X56, X60 and X65 were used. Use of X 70 and X80 and higher grades are gaining momentum to reduce the wall thickness and cost. Special steel grades are used for more corrosive environments such as sour service and for highly corrosive field production pipelines. New higher strength grades require special production methods and controls on chemical composition and toughness properties. MATERIALS RELATED CONSIDERATIONS: MATERIALS RELATED CONSIDERATIONS Newer materials are to be produced through advanced steel melting, tertiary refining and controlled rolling processes to obtain highest quality levels. Typically, Basic open hearth furnace or an LD convertor process in used with special ladle fluxing and vacuum degassing would be required to achieve low levels of C, S, P, Mn, Si and dissolved gases and non-metallic inclusions. Additional steps such as Calcium treatment are to be utilized for inclusion shape control for sour services. Slide 61: Recently, bainitic steels with ultra low carbon and additions of alloying elements such as Mn, Nb, B, Ti, with special online accelerated cooling and controlled rolling steps, are being increasingly used. The need to use faster laying techniques require faster welding techniques which by itself put many restrictions on the material quality, welding processes and manufacturing tolerances, NDT etc. Newer materials such as Duplex stainless steels, High Nickel alloy clad carbon steels, heat traced pipelines etc. are being introduced to tackle corrosive fluids. Slide 62: For all materials used for pipelines, the upper limit of the UTS must be specified in order to restrict the spring back and residual stresses. The ratio yield strength/ UTS must not exceed 0.90, in order to ensure ductile behavior. The residual stress levels should be controlled in order to derive full utility of the strength of the material. The weld metal chosen should have mechanical properties matching the base metal Base metal and weld metal should have sufficiently high impact properties to ensure freedom from brittle fracture in service. For sour service, compliance to NACE requirements must be ensured by testing. 5: 5 INSPECTION & TESTING: INSPECTION & TESTING TESTING OF CHEMICAL COMPOSITION Heat analyses and Sampling methods TESTING OF MECHANICAL PROPERTIES - Tensile tests - Flattening tests - Bend tests - Fracture toughness tests - Hydrostatic tests DIMENSIONAL TESTING SURFACE INSPECTION NONDESTRUCTIVE TESTING Slide 66: COATINGS DESIRABLE CHARACTERISTICS OF COATING : DESIRABLE CHARACTERISTICS OF COATING EFFECTIVE ELECTRICAL INSULATOR EFFECTIVE MOISTURE BARRIER ABILITY TO RESIST DEVELOPMENT OF HOLIDAYS GOOD ADHESION TO PIPE SURFACE RESISTANCE TO DISBONDING EASE OF REPAIR NONTOXIC INTERACTION WITH ENVIRONMENT GOOD HARDNESS/ABRASION RESISTANCE GOOD PENETRATION RESISTANCE GOOD SOIL STRESSING RESISTANCE APPLICABILITY COATING STANDARDS: COATING STANDARDS CSAZ 245.20-06 – External fusion bond epoxy coating for steel pipe (double layer) ISO/FDIS 21809-2:2007(E) – External coatings for buried or submerged pipelines used in pipeline transportation systems- Fusion bonded epoxy coatings (single layer) DIN 30670 – Polyethylene coatings for steel pipes and fittings NACE RP 0169-96 SECTION 5 AWWA C203-02 – Coal tar protective coatings and linings for steel water pipelines TYPES OF PIPELINE COATINGS: TYPES OF PIPELINE COATINGS COAL TAR ENAMEL (CTE) FUSION BONDED EPOXY (FBE), SINGLE AND DUAL LAYER 3 LAYER POLYETHELYNE (3LPE) 3 LAYER POLYPROPYLENE (3LPP) COATING CHARACTERISTICS & LIMITATIONS: COATING CHARACTERISTICS & LIMITATIONS PIPE COATING CHARACTERICTICS LIMITATIONS CTE -Low current requirement Good resistance to cathodic disbondment Good adhesion to steel Limited manufacturers Limited applicators Health and air quality concerns FBE - Low current requirement Excellent resistance to cathodic disbondment Excellent adhesion to steel Excellent resistance to hydrocarbons -High moisture absorption Lower impact and abrasion resistance High application temp 3LPE Lowest current requirement Highest resistance to cathodic disbondment Excellent adhesion to steel Excellent resistance to hydrocarbons High impact and abrasion resistance - Limited applicators Higher initial cost Possible shielding of CP current HARDNESS COMPARISON CURVE: HARDNESS COMPARISON CURVE IMPACT RESISTANCE COMPARISON CURVE AT 20 DEGREE CENTIGRATE: IMPACT RESISTANCE COMPARISON CURVE AT 20 DEGREE CENTIGRATE IMPACT RESISTANCE COMPARISON CURVE AT 20 DEGREE CENTIGRATE: IMPACT RESISTANCE COMPARISON CURVE AT 20 DEGREE CENTIGRATE CATHODIC DISBONDMENT COMPARISON CURVE: CATHODIC DISBONDMENT COMPARISON CURVE PENETRATION COMPARISON CURVE: PENETRATION COMPARISON CURVE WATER ABSORPTION COMPARISON CURVE: WATER ABSORPTION COMPARISON CURVE Slide 77: Inside welding process As the arc is completely covered by the flux layer, heat loss is extremely low. This produces a thermal efficiency as high as 60% (compared with 25% for manual metal arc). There is no visible arc light, welding is spatter-free and there is no need for fume extraction Operating characteristics SAW is usually operated as a fully-mechanised or automatic process, but it can be semi-automatic. Welding parameters: current, arc voltage and travel speed all affect bead shape, depth of penetration and chemical composition of the deposited weld metal. Because the operator cannot see the weld pool, greater reliance must be placed on parameter settings. 5.Submerged Arc Welding Slide 78: Outside Welding Process Process features SAW involves formation of an arc between a continuously-fed bare wire electrode and the work piece. The process uses a flux to generate protective gases and slag, and to add alloying elements to the weld pool. thin layer of flux powder is placed on the workpiece surface. excess flux is recycled via a hopper. Remaining fused slag layers can be easily removed after welding. 5.Submerged Arc Welding Slide 79: Porosity : Causes : Poor steel (high sulfur content) Organic contamination - oil Rusty joint or wire ( moisture bond in the rust) Contaminants in the flux (moisture, dirt and “mil scale) Electrode contamination under unusual storage Insufficient flux Tack welds Arc blow Trapped flux 7.Welding defects Slag:: Slag: a) Poor (convex) weld bead profile resulted in pockets of slag being trapped between the weld runs Causes The slag becomes trapped in the weld when two adjacent weld beads are deposited with inadequate overlap and a void is formed. When the next layer is deposited, the entrapped slag is not melted out. As slag is the residue of the flux coating in MMA welding, it is principally a deoxidation product from the reaction between the flux, air and surface oxide. Slag may also become entrapped in cavities in multi-pass welds through excessive undercut in the weld toe or the uneven surface profile of the preceding weld runs, 7.Welding defects 7. Welding Defects : 7. Welding Defects Lack of penetration: Causes Low current, High welding speed, Low voltage, Poor welding technique 7. Welding Defects: 7. Welding Defects Undercut: Causes High welding speed, Improper electrode angle, High welding current, Improper manipulation of electrodes Weld Reinforcement:: Weld Reinforcement: Correct reinforcement Minimum cost Good joint strength Excess reinforcement High cost Poor joint strength Under reinforcement Poor joint strength 7. Welding defects 8.Welding consumables: 8.Welding consumables 1. Introduction 2. Welding Processes 3. Welding Position & Joints 4. SMAW Process 5. SAW Process 6. Main variables effect 7. Welding defects 8. Welding Consumables 9. Flux Management 10. Welding Procedure and performance qualification 11. Remainder Topics Slide 85: SAW is a combination of two consumables. It can be confusing, and result of that is a lack of confidence in your product. 8.Welding consumables Slide 86: How to choose the proper filler metal ? Flux choice will be driven by : Base metal (stainless/non or low alloy) Single pass or multiple passes (non and low alloyed steels only) Mechanical properties (impacts) Dedicated to one job or “universal “ product in the workshop (optimisation) 8.Welding consumables Slide 87: Flux Normally Used in Pipe Industries: Multipass & / or single pass: 995N = Specific application with LNS 140TB P223 = Good impact and because of his slag freezing point and viscosity very good in spiral pipe mills 960 = Slow speed, large puddles, impact @ 20°C. Plates thickness from 25mm and up 980 = Impact @-0°C, good with contaminated plates. Welding speed can be higher than 960 . Thin gauge plates 8.Welding consumables Slide 88: Electrode Normally Used in Pipe Industries : Single, Multiple or Combination of these - LNS 140TB - EM12K - EA2 (S2Mo) 8.Welding consumables Slide 89: Non & low alloyed steels: 1)Single pass / two run : What is it ? Two different kind of application High tech : 2 passes (pipes) Low tech : one or 2 passes (sound weld at low cost) 8.Welding consumables Slide 90: Basicity of flux : Basi. Index Melting range Acid <0,9 1100°c /1300°c Neutral 0,9<BI<1,2 1300°c/ 1500°c Basic 1,2<BI<2 >1500°c Highly basic <2 >1500°c 8.Welding consumables Slide 91: Why not a fully basic flux for “high quality “ in single or two run technique ? 8.Welding consumables 9. Flux Management: 9. Flux Management 1. Introduction 2. Welding Processes 3. Welding Position & Joints 4. SMAW Process 5. SAW Process 6. Main variables effect 7. Welding defects 8. Welding Consumables 9. Flux Management 10. Welding Procedure and performance qualification 11. Remainder Topics 9.Requirement : 9.Requirement Why flux management is important? Flux shields weld from outside atmosphere Facilitates welding, covers arc Flux is made of materials which produce slag of specific viscosity which allows entrapped gases to come out but provides effective shielding Hygroscopic in nature, absorbs moisture Melts due to weld arc, gets converted to slag, rises to top If contaminated with foreign materials, can produce weld defects 9.Requirement : 9.Requirement Bake for 350 0 C, hold at 80-100 0 C Baking cycle 2 hours, holding time till issue Data: Flux name / number Each bag contains 25 kg Cost Consumption per meter of welding Administration: 2 ovens ID, 2 ovens OD 4 welding stations for ID, 4 for OD 9.Administration-ID welding station: 9.Administration-ID welding station 2 ovens Each oven has 7 trays Fresh flux & recycled flux within closed loop is used Unique system for handling is used System comprises of hoppers, holding tanks, dry air inlet, recovery Temperature for holding can be set 9.Administration-Operating procedure: 9.Administration-Operating procedure Oven is loaded with trays filled for 2” height Oven is set for 350 0 C Time of loading is recorded Batch number is recorded After 350 0 C temperature is reached, time is recorded Flux is held for 2 hours After 2 hours, time is recorded & Either flux is removed & fed to hopper or Temperature is reduced to 80-100 0 C Unloading time is recorded Next loading starts 9.Administration-OD welding station: 9.Administration-OD welding station 2 ovens Each oven has 7 trays collected by suction, fed to feeding tank Recycling: Recycling Recycling is done to reduce cost without effecting quality All foreign material to be separated This is ensured by sieving, passing thru separators Collected & re-baked 9.Administration-ID welding station: 9.Administration-ID welding station 2 ovens Each oven has 7 trays Fresh flux & recycled flux within closed loop is used Unique system for handling is used System comprises of hoppers, holding tanks, dry air inlet, recovery Temperature for holding can be set Slide 100: 10. Welding Procedure and Performance Qualification 1. Introduction 2. Welding Processes 3. Welding Position & Joints 4. SMAW Process 5. SAW Process 6. Main variables effect 7. Welding defects 8. Welding Consumables 9. Flux Management 10. Welding Procedure and performance qualification 11. Remainder Topics Edge Preparation - Need: Edge Preparation - Need Poor penetration Poor access at root Poor strength Good penetration Good access at root Good joint strength Basic Joint Types: Basic Joint Types butt tee lap corner edge Applicable Welds for Butt joint: Applicable Welds for Butt joint Square Groove weld V Groove weld U Groove weld Bevel Groove weld J Groove weld Applicable Welds for Butt joint: Applicable Welds for Butt joint Double V Groove weld Double U Groove weld Double Bevel Groove weld Double J Groove weld Butt joint: Butt joint Single V Groove weld Groove angle Root face Root gap Groove angle Root gap Root radius Single U Groove weld Root face Double V Groove weld Weld Reinforcement: Weld Reinforcement Correct reinforcement Minimum cost Good joint strength Excess reinforcement High cost Poor joint strength Under reinforcement Poor joint strength Butt joint – Complete Joint penetration: Butt joint – Complete Joint penetration Weld from face side Back gouging Back weld Backing weld from root side Back gouging from face side Weld from face side Welding Position – Groove: Welding Position – Groove 1 G 2 G 3 G 4 G Welding Position – Groove: Welding Position – Groove 1 G 2 G 5 G 6 G 45° Dilution: Dilution Dilution is the amount of base metal present in the weld metal and given by (Area B / (Area A + Area B)) Dilution depends on the welding process and heat input. High dilution alters the chemical composition of weld metal Area A Area B Weld Metal Requirements : Weld Metal Requirements Matching strength with the parent metal Good notch toughness at the operating temperature Corrosion resistance Creep resistance for elevated temperature application Resistance to wear, erosion etc Filler Metal Selection : Filler Metal Selection Mechanical / chemical properties required Welding process Type of electrode, current, power range Metal to be joined and its thickness Weld joint design and welding position Shop or Field weld / surface condition Number of passes / amount of weld metal Welding Procedure Specification : Welding Procedure Specification It is a written document that provides direction to the welder for making production welds in accordance with code requirements. Any WPS must be qualified by the manufacturer. WPS specifies the condition (ranges) under which welding must be performed called variables. WPS addresses essential, supplementary essential and non essential variables Purpose of WPS Qualification: Purpose of WPS Qualification To determine that the weldment is capable of providing the required properties for the intended application. WPS establishes the properties of the weldment and not the skill of the welder . Procedure Qualification : Procedure Qualification PQR is a record of welding data to weld a test coupon. It also contains test results. Completed PQR shall document all essential variables including ranges. PQR to be certified accurate and shall not be subcontracted. If more than one process is employed then weld deposit thickness for each process and filler metal to be recorded. Base Metal Classification : Base Metal Classification Base metals classified into various P Nos depending on composition, weldability & mechanical properties. P1 - P11 Steel P21 - P25 Al alloys etc. Group nos. within P nos classify metals for procedure qualification where notch toughness requirements are specified. Filler Metal Classification : Filler Metal Classification F Numbers are based on usability characteristics i.e ability of welders to make satisfactory welds with given filler e.g. F1 - E XX20, F2 - E XX12, F3 - E XX10, F4 - E XX18 etc. A Numbers are based on chemical composition e.g. A1 - Mild steel A2 - C - Mo steel etc. WPS for SMAW: WPS for SMAW Essential variables Change in qualified Thickness Change in P no Change in F no of filler metal Change in A no of filler metal Change in deposited metal thickness Decrease of more than 100° F in preheat Change in PWHT Procedure Qualification Thickness limits : Procedure Qualification Thickness limits T (mm) Range of T max t Tests <1.6 T - 2T 2t 2T, 2 FB, 2 RB 1.6 – 10 1.6 - 2T 2t -do- 10 - 19 4.8 - 2T 2t -do- 19 - 38 4.8 - 2T 2t if t<19 2T, 4 SB 2T if t>19 >38 4.8 - 203 2t if t<19 -do- 203 if t>19 Welding Performance Qualification : Welding Performance Qualification The performance qualification tests are intended to determine the ability of welders to make sound welds A welder is qualified by radiography of a test coupon or by radiography of initial production welding or by bend tests taken from a test coupon Welding Performance Qualification : Welding Performance Qualification The performance qualification tests are intended to determine the ability of welders to make sound welds A welder is qualified by radiography of a test coupon or by radiography of initial production welding or by bend tests taken from a test coupon Welding Performance Qualification : Welding Performance Qualification Variables for SMAW Removal of backing Change in Pipe diameter Change in P number Change in F Number Change in thickness of weld deposit Change in welding position Change in vertical welding Slide 123: 11.Reminder 1. Introduction 2. Welding Processes 3. Welding Position & Joints 4. SMAW Process 5. SAW Process 6. Main variables effect 7. Welding defects 8. Welding Consumables 9. Flux Management 10. Welding Procedure and performance qualification 11. Remainder Topics Possibilities for Welding-Seam Monitoring by Personnel in Submerged-Arc Welding Plants: Possibilities for Welding-Seam Monitoring by Personnel in Submerged-Arc Welding Plants Visual Assessment of the Pipe to be Final-Welded One prerequisite for a high-quality submerged-arc welding seam is proper preparation of the inside and outside seam area. The seam area must be free from rust and scale. It is imperative that the surface is free from oil, grease and water. The tack-welded seam must be uniform. Both the strip edges must have the same contour from the miller. If these points are not complied with, this results in contamination of the welding seam by slag and pores and in irregularities in the arc and thus poorer seam geometry and penetration notches. 11.Reminder Slide 125: 11.Reminder B) Checking of Specified Production Data In principle, every operator must convince himself at the start of the shift that the production data specified for the order in question (current intensity, voltage, welding speed and welding-wire position) has been set correctly. If welding-seam faults are found as a result of the micrographs or non-destructive testing or if there are any irregularities in the production sequence which have a negative influence on the welding seam, then the production data must be checked immediately, including checking of the welding-wire feed and of the flux supply. Slide 126: 11.Reminder C) Observation of Production Sequence Attention must always be paid to the constancy of the measuring-instrument displays for the electrical welding data. The regularity and temperature of glowing-through during the welding process must be observed. The flux feed must be adequate, regular and symmetrical to the centre of the seam. Constant wire discharge is shown by steady welding data, uniform glowing through and a stable position of the inside arm. Surrounding influences, such as shocks to the installations as a result of pipe transport, sticking of control elements, wearing of parts of the installation, jerking of the pipe etc., must be observed and eliminated immediately. Slide 127: 11.Reminder D) External Assessment of Welding Seam External inspection and measurement of the seam is often sufficient to provide information about the quality of the welding seam. It is thus possible to assess the regularity and dimensions (height and width) of the seam shape. In most cases, impermissible faults, such as notches, external pores, seam protuberances, seam offset and seam interruptions, are obvious. E) Metallographic Micrograph Assessment The metallographic micrograph of the submerged-arc welding seam primarily serves to assess the seam geometry, the seam shape and the heat influence in the seam area. It also enables information to be given about the purity of the welding seam and about the material properties. During ongoing operational testing, the following data is determined and registered on the basis of the micrographs: excess seam height, seam width, seam offset, width / transition zone, penetration figure and normalization. If faults are included in the welding deposit or in the base material, special marking is applied. Process route for Hot finished Product: Process route for Hot finished Product Process route for Casing & Tubing: Process route for Casing & Tubing Process route for anti-corrosion coating: Process route for anti-corrosion coating Process route for Cold-finished Product: Process route for Cold-finished Product Survey of API-leveller information format data: Survey of API- leveller information format data PIPE MILLS INCLUDED ARE:- WELSPUN GUJARAT. JINDAL SAW LTD. PSL LIMITED. RATNAMANI LTD. MAN INDUSTRIES LIMITED. Slide 133: No.1 leveller No.2 leveller ①-1 ②-1 ③-1 ④-1 ④-2 ①-2 ②-2 ③-2 ① work roll diameter ② pitch between the center of upper 1 st roll and the center of upper 2 nd roll ③ the distance between the center of upper roll and the center of bottom roll = ④ intermesh (roll gap) ⑤ maximum motor power of each leveller. ⑥ wheather or not the back up roll is exist. (if back up roll is exist, then it needs of back up roll ’ s information like work roll.) Slide 134: Tube making line No 1 st leveller 2 nd leveller Upper/ Lower No of roll Work Roll Diameter Motor pressure Max Have a Back-up roll? Upper/ Lower No of roll Work Roll Diameter Motor pressure Max Have a Back-up roll? Spiral no.1 2/1 300mm 100bar No 3/2 250mm 150bar Yes Spiral no.2 2/1 250mm 80bar Yes 2/1 200mm 100bar Yes Leveller information format Slide 135: LEVELLER INFORMATION Tube making line No 1 st leveller (Non drive) 2 nd leveller (Non drive) Upper/Lower No of roll 1- Work Roll Diameter 2- pitch between upper 1 st & 2 nd roll 3- center of upper roll and the center of bottom roll 4- intermesh (roll gap) Motor power/ pressure Max for work roll up down Have a Back-up roll? Upper/Lower No of roll 1- Work Roll Diameter 2- pitch between upper 1 st & 2 nd roll 3- center of upper roll and the center of bottom roll 4- intermesh (roll gap) Motor power/ pressure Max for work roll up down Have a Back-up roll? Spiral no.-1 3/4 340mm 360mm 440mm 80mm 23.6kw / screw jack No No Spiral no.-2 2/1 340mm 350mm 400mm 60mm hyd. Cylinder / 100 bar No 2/3 340mm 360mm 340mm 00mm 2.2kw/ screw jack Yes Spiral no.-3 2/1 340mm 350mm 400mm 60mm hyd. Cylinder / 100 bar No 2/3 340mm 360mm 340mm 00mm 2.2kw/ screw jack Yes 1 st leveller back up roll 2 nd leveller back up roll Upper wrok roll & bottom back up roll back up roll Diameter 2- pitch between bottom work roll & back up roll 3- center of bottom work roll & back up roll 4- intermesh (roll gap) Remarks Upper wrok roll & bottom back up roll back up roll Diameter 2- pitch between bottom work roll & back up roll 3- center of bottom work roll & back up roll 4- intermesh (roll gap) Remarks Spiral no.-1 No No Spiral no.-2 No 1/2 190mm 240mm 236.27mm - Spiral no.-3 No 1/2 190mm 240mm 236.27mm -