ERD - Level 4
Pumps: Notes
Safety precautions when installing, servicing or maintaining pumps.
When we work on pumps for any reason at all we should take the following precautions:
l Work in a clean dry environment. Parts of the pump, like the bearing, must be free of dust and contaminants when installed to prevent excessive wear and tear.
l Make sure a lock out device is in place. This will prevent accidental connection of the pump while you are working on the pump.
l Ensure that the pump is turned off and not operating when you start working on the pump.
l Wear the necessary PPE
l Use the correct tools for the correct job.
l Make sure that you have the correct spares to replace broken parts.
Plan and prepare for pump maintenance.
Mechanical Inspection:
· Check that mounting points are secure
· Check for excessive vibration and noise
· Inspect the mechanical seal and packing
· Inspect the pump flanges for leaks
· Inspect coupling and alignment.
Lubrication:
· Lubricate the motor and pump bearing per manufacturer’s guidelines. Do not over lubricate! More bearing damage occurs as a result of over greasing than under greasing. If the bearing has a vent cap, remove the cap and run pump for 30 minutes before reinstalling cap. This allows excess grease to work its way out of the bearing.
Electrical/motor:
· Check that all terminations are tight
· Inspect starter/contractor for arcing, overheating, etc.
· Put a megohmmeter on the windings to check for insulation failure
Following the outline above will ensure that your pump lives a long and productive life – hopefully without incident!
Dismantle and assemble pumps
1. Ensure that the correct tools are available to dismantle and reassemble the pump.
2. Use the proper equipment to lift and move heavy objects
3. Make sure the lockout devise is in place
4. If pump is used to pump poisonous or hazardous liquids, make sure that the pump is rinsed out and clean with none of the hazardous liquids still present inside
5. Allow pump and components to cool down before dismantling it.
6. Disconnect all piping and tubing from the pump
7. Disconnect coupling
8. Drain oil and lubricants from pump
9. Clean and inspect all parts
10. Replace all broken parts
11. Reassemble the parts
12. Test the pump by turning it by hand
13. Inspect the pump for any leaks
14. Connect and align coupling
15. Run pumps for couple of minutes to listen for strange noises and to visually inspect for leaks
Types of pumps
The positive displacement pump can be classified as:
· Reciprocating pumps - piston, plunger and diaphragm.
· Power pumps.
· Steam pumps.
· Rotary pumps - gear, lobe, screw, vane, regenerative (peripheral) and progressive cavity.
Dynamic Pumps
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Positive Displacement Pumps
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Dynamic pumps include all types of pumps using fluid velocity and the resulting momentum to pump and move the fluid through the piping system.
Although dynamic pumps usually have lower efficiency than positive displacement pumps, they require lower maintenance. They are also capable of operating at high speeds and high fluid flow rates.
Classification of Dynamic Pumps
Dynamic pumps can be classified into the following sub-categories:
· Rotary Pumps
o Centrifugal Pumps
o Axial Flow Pumps
o Mixed Flow Pumps
· Special Pumps
o Jet Pumps
o Electromagnetic Pumps for Liquids & Metals
o Fluid Actuated/Gas Lift or Hydraulic Pumps
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Positive displacement pumps operate by filling and displacing liquid from a cavity. Such pumps deliver a constant flow and volume of liquid without discharge pressure or head.
Positive displacement pumps are ideal for a low flow–high pressure combination, and other application niches.
Classification of Positive Displacement Pumps
Positive displacement pumps can be classified into the following sub-categories:
· Reciprocating Pumps
o Piston / Plunger Pumps
§ Single Acting Piston Pumps
§ Double Acting Simplex Pumps
§ Double Acting Duplex Pumps
o Diaphragm Pumps
§ Single Diaphragm
§ Double Diaphragm
o Rotary Pumps
§ Single Rotor Pumps
§ Sliding Vane Pumps
§ Flexible Tube or Lining Pumps
§ Screw Pumps
§ Radial Pumps
§ Multiple Rotor Pumps
§ Gear Pumps
§ Double Lobe Pumps
§ Triple Lobe Pump
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Compressors: Notes
FAILURE TO MAKE THESE RECOMMENDED CHECKS COULD RESULT IN SERIOUS INJURY, PROPERTY DAMAGE, AND MECHANICAL FAILURE.
1. Remove all loose pieces and tools around the compressor installation.
2. Check oil level in crankcase.
3. Check motor and compressor pulley for alignment and tightness on shaft
4. Be absolutely certain that all mounting bolts are tight.
5. Manually rotate compressor through enough revolutions to be certain there are no mechanical interference.
6. Check belt tension, it should be neither too loose nor too tight.
7. Check all pressure connections for tightness.
8. Check to make sure all safety relief valves are in place.
9. Check to be sure all guards are in place and securely mounted.
10. Check fuses, circuit breakers and thermal overloads for proper size.
11. Open all manual shutoff valves (block valves) at and beyond the compressor discharge.
After all of the above conditions have been satisfied, jog the starter switch button to check the rotational direction of the compressor, it should agree with the rotation arrow on the unit. Follow this procedure for start up of a new installation, after changes to an existing installation have been made, and after service or repairs have been performed.
1. Instructions in addition to those contained within this manual, supplied by manufacturer of support equipment, must also be read and understood before start-up.
2. Jog starter button and check compressor rotation.
3. Start compressor and watch for excessive vibration and noises. If either is present, stop compressor and correct.
4. Check air receiver pressure.
5. Manually blow safety relief valve(s).
6. Check operation of controls.
7. Observe general compressor operation closely for first hour and then frequently for next seven hours. If any abnormal conditions exist, stop compressor and correct the problem.
8. After two days of operation, check belt tension, air and oil piping for leaks and crankcase oil level.
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