Ampco Pumps Company K-Series Metric Maintenance Manual M-033 Rev A 11.16
2
General Piping Notes
•
Pipe hangars or other supports must be used at proper intervals to ensure proper piping
support near the pump.
Do not use the pump to support piping!
•
When flange bolts are tightened no strain should be transmitted to the pump, thus
suction and discharge piping should be supported independent of the pump and care
should be taken that the pump and piping are properly aligned.
•
Piping must be as straight as possible. Avoid all unnecessary bends and fittings. When
bends are necessary use 45
°
or long-sweep 90
°
pipe fittings in order to decrease minor
friction losses.
•
Make sure all flanged joints have matching inside diameters and properly aligned
mounting holes – especially close to the pump.
•
Do not force piping when making connections. This can cause the impeller to rub
on the casing or premature seal failure.
Suction Piping
It is very important that suction piping be selected and installed such that it minimizes
pressure loss and allows sufficient liquid flow into the pump. A proper suction piping system
design can eliminate many NPSH problems. The following precautions should be followed to
ensure a proper suction piping system.
•
Suction piping must be kept as direct as possible. It is suggested that any elbows be
kept at least 5 pipe diameters away from the pump’s suction flange.
•
Suction piping length should be at least ten times the pipe diameter overall.
•
When suction piping has a larger diameter than the pump suction opening an eccentric
reducer must be used, with the taper oriented down. (Note: Do not use a concentric
reducer)
•
Suction piping must never have a smaller diameter than the pump suction opening.
•
When possible, horizontal suction piping should follow an even gradient.
