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Part 4 of 4

It is good practice to initially fill the pump and as much of the inlet piping system as possible with the liquid to be pumped. This will assist in priming and reduce the risk of pump damage during an otherwise dry start. A rotary pump will prime more quickly if internal pumping elements are at least wetted. Priming is nothing more than pumping air from the inlet system to the discharge system. The ability of a rotary positive displacement pump to act as an air compressor is very much related to having some liquid present internally.

Pump shaft seals, especially mechanical seals, should never be operated dry. Immediate, or at best premature, seal failure is the inevitable result. Again, filling the pump with the liquid to be pumped and hand rotating the pump a few times helps ensure that liquid is present at the shaft sealing mechanism to carry away frictional heat during startup. If the particular pump has a seal chamber access plug, remove the plug, fill the chamber with liquid and reinstall the plug.

Have phone numbers of key vendor service departments, fire brigade and medical emergency services on hand in the event they are needed. When handling petroleum and other flammable liquids, there are both pollution and fire hazards present.

Ensure that there is an adequate supply of liquid in the pump inlet system (no half empty supply oil tanks or the like). It is also prudent to confirm where pump discharge flow will be going to be sure the discharge system is ready.

Loud or erratic noise at startup is an indication of cavitation (inadequate pump inlet pressure) or air being drawn into the pump inlet system. It is frequently accompanied by increases in or excessive vibration. If mild, troubleshoot the cause. If severe, shut down the pump and find the source of the problem.

Use the ROTARY PUMP STARTUP CHECK LIST or a similar control to help ensure that all contingencies have been addressed.

CONCLUSION

Our discussion cannot be considered all-inclusive since each pumping system has unique features and requirements, some of which may interact with each other or with other aspects of the overall plant operation. In addition, no allowance has been made here for regulatory requirements, specialised industry or company guidelines or the like. Where values are recommended, they are intended for use in the absence of vendor or specifically engineered information. Always use the more stringent of either the recommendations herein or the vendor or engineer’s guidelines.

ROTARY PUMP

Project:__________Location:__________Unit No.:__________Tag No.:_________

1. PIPING 7. SPARES AVAILABLE

❏ Clean ❏ Pump

❏ Bolts Tight ❏ Driver

❏ Strain Removed ❏ Gear

❏ Gaskets in Place ❏ Other__________

❏ Pressure Tested

❏ Flushed 8. RESOURCES AVAILABLE

❏ Other__________ ❏ Electric

❏ Steam

2. VALVES ❏ Cooling Water

❏ Not Backwards ❏ Hot Oil

❏ Clean ❏ Auxiliaries

❏ Bolts Tight ❏ Gages in Place

❏ Gaskets in Place ❏ Other__________

❏ Correct Position (Open/Close)

❏ Relief Valve Set Pressure 9. LAST MINUTE

❏ Other__________ ❏ Pump Filled with Liquid

❏ Shaft Seals Wetted

❏ Key Contact Phone Nos.

3. FOUNDATION ❏ Inlet Liquid Supply

❏ Level ❏ Discharge System Ready

❏ Solid (No Voids) ❏ Air Bleed Valve Open

❏ Bolts Tight ❏ Pump Hand Rotated

❏ Other__________ ❏ Other__________

10. COMPANY/INDUSTRY SPECIFIC

4. ALIGNMENT ❏ _______________

❏ Angular (Cold & Hot)_____ _____ ❏ _______________

❏ Parallel (Cold & Hot)_____ _____ ❏ _______________

❏ Other__________ ❏ _______________

❏ _______________

5. ROTATION

❏ Verified (CW or CCW)

❏ Other__________

6. LUBRICATION

❏ Pump

❏ Driver

❏ Gear

❏ Other__________

7. SPARES AVAILABLE

❏ Pump

❏ Driver

❏ Gear

❏ Other_______

8. RESOURCES AVAILABLE

❏ Electric

❏Steam

❏ Compressed air

❏Cooling water

❏ Hot oil

❏ Auxiliaries

❏ Gages in place

❏ Other_________

9. LAST MINUTE

❏ Pump filled with liquid

❏ Shaft seals wetted

❏ Key contact phone numbers

❏ Inlet liquid supply

❏ Discharge system ready

❏ Air bleed valve open

❏ Pump hand rotated

❏ Other____________

10. COMPANY SPECIFIC

❏ _________________

❏ _________________

❏ _________________

❏ _________________

❏ _________________

For more information, contact Jim Brennan at

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