Gorman-Rupp Pumps 3D-B 883512 and up - Manual (Page 10)

D SERIES OM−01490
PAGE B − 3 INSTALLATION
Fixed, Rigid Piping
This pump is equipped with an integral suction ac-
cumulator chamber which promotes an efficient
flow of liquid and acts as an air cushion against
shock. Since the air in this chamber will leak away
during pump operation, the air must be replen-
ished periodically. To introduce air into the cham-
ber, stop the pump and remove the suction accu-
mulator plug and integral gasket; this will break
prime and allow the liquid in the chamber to drain
away through the suction line.
If the pump is mounted in a system with fixed, rigid
piping, it is recommended that a flexible connec-
tion be installed at or near the suction and dis-
charge ports to absorb shock which would other-
wise be transmitted through the drive train and
greatly accelerate pump wear.
In a fixed piping installation, properly sized surge
suppressors must be installed in both suction and
discharge lines. If commercial surge suppressors
are not readily available, air chambers may be fab-
ricated from pipe as shown in Figure 2.
AIR CHAMBERS
(18 TO 24 INCH LENGTHS OF
6 TO 8 INCH DIAMETER PIPE
WITH WELDED CAPS)
DISCHARGE
CHAMBER
DISCHARGE
FLEXIBLE JOINT
FLEXIBLE JOINT
SUCTION
CHAMBER
1/2-INCH VALVE FOR
RECHARGING AIR
CHAMBER WITH
COMPRESSED AIR
(ALSO ON DISCHARGE
CHAMBER)
SUCTION
NOTE: INSTALL AIR CHAMBERS OFF FLOW LINE TEES
TO AVOID SURFACE TURBULENCE WITHIN CHAMBERS.
Figure 2. Fixed Piping Installation
Note that the air chambers have not been installed
directly in the flow line, but have been installed off
tees to avoid turbulence within the chambers. The
air chambers are fitted with valves to permit intro-
duction of small amounts of compressed air to fur-
ther dampen shock; this compressed air will leak
away during operation, and should be replaced
from time to time. If the suction chamber floods,
open the suction chamber valve to break prime
and allow the liquid in chamber to drain through
the suction line. Gauges
If discharge pressure and vacuum suction gauges
are desired, drill and tap the suction and discharge
lines not less than 18 inches (457,2 mm) from the
suction and discharge ports and install the lines.
Installation closer to the pump may result in erratic
readings.