Installation
GeneralInformation
The Typical Installation shown is only a guide
for selecting and installing system components.
Contact your Graco distributor for assistance in
planning a system to suit your needs. Always use
Genuine Graco Parts and Accessories. Be sure all
accessories are adequately sized and pressure rated
to meet the system’s requirements.
Reference letters in the text, for example (A), refer to
the callouts in the figures.
NOTE: For outdoor applications, be sure to provide
adequate protection from the elements.
Tighten Fasteners
Before mounting and using the pump for the first time,
check and retorque all external fasteners. Follow
, or see the torque
tag on your pump. After the first day of operation,
retorque the fasteners.
Tips to Reduce Cavitation
Cavitation in a double diaphragm pump is the
formation and collapse of bubbles in the pumped
liquid. Frequent or excessive cavitation can cause
serious damage, including pitting and early wear of
fluid chambers, balls, and seats. It may result in
reduced efficiency of the pump. Cavitation damage
and reduced efficiency both result in increased
operating costs.
Cavitation depends on the vapor pressure of the
pumped liquid, the system suction pressure, and the
velocity pressure. It can be reduced by changing any
of these factors.
1. Reduce vapor pressure: Decrease the
temperature of the pumped liquid.
2. Increase suction pressure:
a. Lower the installed position of the pump
relative to the liquid level in the supply.
b. Reduce the friction length of the suction
piping. Remember that fittings add friction
length to the piping. Reduce the number of
fittings to reduce the friction length.
c. Increase the size of the suction piping.
d. Increase the Net Positive Suction
Head Available (NPSHa). See
.
NOTE: Be sure the inlet fluid pressure does not
exceed 25% of the outlet working pressure.
3. Reduce liquid velocity: Slow the cyclic rate of
the pump.
Pumped liquid viscosity is also very important but
normally is controlled by factors that are process
dependent and cannot be changed to reduce
cavitation. Viscous liquids are more difficult to pump
and more prone to cavitation.
Graco recommends taking all of the above factors
into account in system design. To maintain pump
efficiency, supply only enough power to the pump to
achieve the required flow.
Graco distributors can supply site specific
suggestions to improve pump performance and
reduce operating costs.
10
334188P
Tel: 866-777-6060
Fax: 866-777-6383
Springer Pumps, LLC
Website: www.springerpumps.com
Int'l: +001 267 404 2910
