Pulsafeeder Pulsar Shadow - Manual (Page 12)

7
4.2 Piping System
All piping systems should include:
1. Shutoff valves and unions (or flanges) on
suction and discharge piping. This
permits check valve inspection without
draining long runs of piping. Shutoff
valves should be of the same size as
connecting pipe. Ball valves are
preferred since they offer minimum flow
restriction.
2. An inlet strainer, if the product is not a
slurry. Pump check valves are
susceptible to dirt and other solid
contaminants unless designed for that
service, and any accumulation can cause
a malfunction. The strainer should be
located between the suction shutoff valve
and the pump suction valve. It must be
sized to accommodate the flow rate and
the anticipated level of contamination.
100-mesh screen is recommended.
3. Vacuum/pressure gauges in the suction
and discharge lines in order to check
system operation. Gauges should be
fitted with protective shutoff valves for
isolation while not in use.
4. A separate system relief valve to protect
piping and process equipment, including
the pump, from excess process pressures.
Figure 8
The hydraulic bypass valve (HBV) in the pump is not intended to protect the system!
Piping weight must not be supported by the valve housings or other portions of the reagent head, as the
resulting stresses can cause leaks. If appropriate, provide for thermal expansion and contraction so that
no excess force or moments are applied to the pump.
In piping assembly, use a sealing compound chemically compatible with the process material.
Users of sealing tape are cautioned to ensure that the pipe thread ends are not taped. 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. Flow issues at pump startup are often
related to the check valves being fouled with piping and process debris.