Maintenance of Reciprocating ammonia Feed Pump

Views:
 
     
 

Presentation Description

maintenance of ammonia Feed Pump

Comments

Presentation Transcript

slide 1:

MAINTENANCE OF RECIPROCATING AMMONIA FEED PUMP Author Prem Baboo Sr. Manager Prod National Fertilizers Ltd. Vijaipur India Following regularly maintenance are required for Ammonia reciprocating Feed pumps 1. Tandem valve maintenance 2. Plunger packing maintenance. 3. Crank Case Maintenance 4. Other maintenance 1. PREVENTATIVE MAINTENANCE OF TANDEM VALVES At least once every four months check for proper operation by following the preventative maintenance steps outlined below. These steps can be performed while the actuator is in service and in some cases without interrupting service. Generally by experience internal passing sound are coming from block means the “ O” ring to be replaced.

slide 2:

1. Clean and lubricate all internal parts. All O-rings should be replaced and lubricated using a silicone lubricant. The bore that houses the sliding seal assembly in the transfer case must be smooth and clean. 2. Reassemble the sliding seal assembly by pushing the base seal into the transfer case. Place the sliding seal collar on top of the base seal so that the raised portion of the sliding collar protrudes through the hole in the top clamp. 3. Replace the top clamp and the spiral snap-ring. Fig-1 Tandem Valves

slide 3:

Fig.-2. High Pressure Block

slide 4:

2. PLUNGER PACKING REPLACEMENT In a reciprocating pump in which a plunger is slid ably disposed within a pumping chamber for reciprocating movement therein it is necessary to provide packing for the plunger to prevent the leakage of liquid out of the pumping chamber between the plunger and the cylinder wall. It is a common practice to provide a bore in the head of the pumping chamber for the packing box. However with this type of construction it is difficult to replace the worn packing without removing the plunger from the head of the pumping chamber especially if the packing is of the closed ring type. Reciprocating pumps use various method of packing as their sealing methodology. For packing to be reliable it must always be in contact with lubricant such as pump product or an external flash like steam condensate. The flow for plunger about 120 lit/hr./plunger Sample of ammonia plunger packing outlet should be done regularly twice in week. We are allowed about 12.0 ammonia in plunger packing outlet analysis Sample Plunger packing outlet analysis for ammonia by lab. Sample Points Ammonia analysis Status Plunger No. 1 5.0 Ok Plunger No. 2 7.0 Ok Plunger no. 3 14.0 Plunger packing tightening to be done

slide 5:

About two month plunger packing tightening is required for reducing ammonia contents in plunger outlet water. Plunger packing life about 2.0 to 2.5 years depends upon packing quality. We are using Inmarco packing. Fig. 3. Packing material Enmarco Fig. 4. Stuffing box 3. CRANK CASE MAINTENANCE

slide 6:

As you know this device can protect the pump against overload around the shaft The reason of the overload can be as following items: 1. closing of control valve or hand valve in the discharge of the pump. 2. Suddenly increasing in the synthesis pressure. No action can take during checking of the overload only the distance between switch and body of crank shaft must be measure and checked in specific time intervals

slide 7:

Crank case Overload Protection switch As you know this device can protect the pump against overload around the shaft .The reason of the overload can be as following items: 1-closing of control valve or hand valve in the discharge of the pump. 2-Sundenly increasing in the synthesis Pressure. No action can take during checking of the overload .only the distance between switch and body of crank shaft must be measure and cheeked at the operating pressure of the ammonia feed pump i.e. 240 ata. Fig.5. Crank case Overload Protection switch

slide 8:

Over load Protection Grooves Calibration of over load Protection Switch at the Pressure of 240 ata.

slide 9:

Calibration of over load Protection Switch at the Pressure of 240 ata.

slide 12:

Water in Crankcase Oil 1. Water Condensation. 2. Worn seals. 3. Clogged Air Breathers. 4. Worn Crankcase Packing. 5. Loose Covers Oil Leakage from Crankcase 1. Oil Level/Temperature Too High. 2. Worn seals. 3. Worn Crankcase Packing. 4. Loose Crankcase Cover Excessive Heat in Power End. 1. Pump Running Backward/RPM too low Insufficient Oil in Power End. 2. Excessive Oil in Power End. Incorrect Oil Viscosity. 3. Operating Pump above Recommended Pressure 6 Main Bearings too Tight. 4. Drive Misaligned. 5. Suction dampener tracing steam closed 6. Pump RPM too Low. 7. Inadequate Ventilation. 8. Liquid end Packing Adjusted too Tight adjustable style packing only 4. OTHERS PROBLEMS Like all other pump designs reciprocating positive displacement pumps have their own set of disadvantages with the most common being the pulsations. The pulsating flow and pressure have specific suction and discharge piping system requirement to ensure proper pump performance and to protect the piping and other system components like discharge resonator and suction dampener. A STUD FAILUR 1. Excessive discharge pressure. 2. Improper torqueing of nuts. 3. Shock overload caused by pump cavitation’s’ B EXCESSIVE VALVE NOISE 1. Broken or weak valve spring. 2. Pump cavitation’s’. 3. Air leak in inlet piping or loose bolts in pump inlet manifold. 4. Air trapped above inlet valve

slide 13:

Noisy Operation Be sure to differentiate between liquid knock and mechanical knock - very few knocks are mechanical on new installations. 1. Piston or plunger loose 2. Valve noise amplified through power end 3. Pump cavitation’s 4. Liquid knock 5. Air leak in inlet piping 6. Loose bolts in pump inlet manifold 7. Hydraulic noise in liquid end 8. Loose or worn crosshead pins and bushings 9. Loose connecting rod cap bolt 10. Worn connecting rod bearings 11. Worn crosshead 12. Main bearing end play excessive 13. Worn gears 14. Gears out of line 15. Partial loss of prime 16. Shocks in piping system 17. Steam closed in suction dampener tracing.

authorStream Live Help