Best Practices for ANSI Pumps
- Operate pumps at 85% to 110% of best efficiency point (BEP).
- Ensure NPSHA is 20% or 1.5m (5ft) over NPSHR, whichever is greater.
- Impeller trims of 75% are optimal, so trim impellers 60% to 95% of maximum.
- Consider using variable speed technology for multiple operating point conditions.
- Level pump, base & motor, and ensure the area is free of soft foot conditions.
- Provide at least 10 diameters of straight pipe to the pump’s suction inlet.
- Use highly rigid baseplates, such as reinforced stilt or grout installed designs.
- Utilize low shrink grout to install baseplates. Epoxy grout is superior.
- Design piping to ensure minimum stress, i.e., fasteners should be installed without force.
- Use laser or reverse dial indicator technology to align pump & motor.
- Align before and after the pump & piping are bolted together.
- Consider using C-flange motor adapters when pumping fluids hotter than 95°C (200°F).
- For pumping temperatures greater than 175°C (350°F) consider centerline mounted casing.
- Refer to equipment operation & maintenance manuals for start-up procedures and checklists.
- Slowly close process valves to avoid water hammer.
- Consider soft start for frequent on-off duty pumps.
- Avoid run-dry conditions.
- Operate spare pumps at least every three months to maintain proper working conditions.
- Change lubrication at recommended intervals.
- Protect lubricant from contamination.
- Maintain mechanical seal flush environment.
- Predictive maintenance, vibration monitoring and lubricant analysis are beneficial practices.