Owner's manual

Piping System Recommendations

1. When making the threaded joint to the valve cap assembly, use a sealing compound chemically

compatible with the process material (for example Loctite® 8551 [Loctite is a registered Trade Mark of

Henkel Corporation] for water service). Do not use sealing tape. The valve cap should be tightened by

hand and then tightened 1 additional turn (i.e., 360 degrees) with the aid of an adjustable wrench.

2. Both new and existing piping should be cleaned, preferably by flushing with a clean liquid (compatible

with process material) and blown out with air, prior to connection to the pump.

Note - Debris from manufacturing the piping system (e.g., PVC shavings, TFE Tape, dirt, etc.)

can be unknowingly assembled inside the pipe. When fluid is introduced this material can be

transferred to the pump and prevent proper check valve operation. This is a common startup

issue.

3. Piping weight must not be supported by valve housings or other portions of the reagent head, as the

resulting stresses can cause leaks. Valve loads must not exceed 13.5 N-M (10 FT-LBF) moment or

22N (5 LBF) in any direction. When temperature variations are expected provide for thermal

expansion and contraction of piping components so that force and/or moments are controlled within

the allowable range.

4. When making process connections, ensure that pipe joint cement and thread sealants do not run into

the check valve assemblies as this will inhibit valve operation. This is a common startup issue.

2.4 Suction Pressure Requirements

Although PULSA GLM

metering pumps have some suction lift capability, a flooded suction (i.e., suction

pressure higher than atmospheric pressure) is preferable whenever possible. The pump should be

located as close as possible to the suction side reservoir or fluid supply source.

For fluid with a vapor pressure of 0.35 Bar (5 psia) or less (at operating temperature) the wet suction lift

capability is approximately 3 meters (10 feet). If this requirement is not met, the pump will not provide

reliable, accurate flow. In suction lift conditions, the use of a foot valve is recommended at the lowest

point of the pickup tube or pipe. Pumps operating under suction lift conditions may require some liquid

priming before they will operate reliably.