Gorman-Rupp Pumps RD2A31-BAR All serial numbers - Manual (Page 9)

OM-03989 RS AND RD SERIES PUMPS
PAGE B - 3 INSTALLATION
Materials
Either pipe or hose maybe used for suction and
discharge lines; however, the materials must be
compatible with the liquid being pumped. If hose is
used in suction lines, it must be the rigid‐wall, rein­
forced type to prevent collapse under suction. Us­
ing piping couplings in suction lines is not recom­
mended.
Line Configuration
Keep suction and discharge lines as straight as
possible to minimize friction losses. Make mini­
mum use of elbows and fittings, which substan­
tially increase friction loss. If elbows are necessary,
use the long‐radius type to minimize friction loss.
Connections to Pump
Before tightening a connecting flange, align it ex­
actly with the pump port. Never pull a pipe line into
place by tightening the flange bolts and/or cou­
plings.
Lines near the pump must be independently sup­
ported to avoid strain on the pump which could
cause excessive vibration, decreased bearing life,
and increased shaft and seal wear. If hose‐type
lines are used, they should have adequate support
to secure them when filled with liquid and under
pressure.
Gauges
Most pumps are drilled and tapped for installing
discharge pressure and vacuum suction gauges. If
these gauges are desired for pumps that are not
tapped, 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.
SUCTION LINES
To avoid air pockets which could affect pump prim­
ing, the suction line must be as short and direct as
possible. When operation involves a suction lift, the
line must always slope upward to the pump from
the source of the liquid being pumped; if the line
slopes down to the pump at any point along the
suction run, air pockets will be created.
Refer to Figure 1 for the recommended configura­
tion of the suction line.
INCORRECT PITCH
VAPOR
POCKETS
INCORRECT LOOPS
RECOMMENDED
NO
POCKETS
PITCH UP TO
SUCTION
WITH NO
LOOPS
VAPOR
POCKETS
Figure 1. Suction Line Configuration