Gorman-Rupp Pumps 612M60-B 1453214 and up - Manual (Page 11)

OM−04407 60 SERIES
PAGE B − 4 INSTALLATION
Figure B−2. Recommended Minimum Suction Line Submergence vs. Velocity
DISCHARGE LINES
Siphoning
Do not terminate the discharge line at a level lower
than that of the liquid being pumped unless a si-
phon breaker is used in the line. Otherwise, a si-
phoning action causing damage to the pump
could result.
Valves
If a throttling valve is desired in the discharge line,
use a valve as large as the largest pipe to minimize
friction losses. Never install a throttling valve in a
suction line.
A check valve in the discharge line is normally rec-
ommended, but it is not necessary in low dis-
charge head applications.
With high discharge heads, it is recommended that
a throttling valve and a system check valve be in-
stalled in the discharge line to protect the pump
from excessive shock pressure and reverse rota-
tion when it is stopped.
If the application involves a high discharge
head, gradually close the discharge
throttling valve before stopping the pump.
Bypass Lines
If it is necessary to permit the escape of air to at-
mosphere during initial priming or in the repriming
cycle, install a bypass line (sized so that it will not
affect pump discharge capacity) between the
pump and the discharge check valve. Since this
pump does not use a suction check valve, the dis-
charge end of the bypass line must be submerged
in the liquid being pumped in order to maintain
suction.
ALIGNMENT
The alignment of the pump and its power source is
critical for trouble-free mechanical operation. In
either a flexible coupling or V-belt driven system,
the driver and pump must be mounted so that their
shafts are aligned with and parallel to each other. It