Gorman-Rupp Pumps T10A3S-B /FM,/WW - Manual (Page 11)

OM-05290 SUPER T SERIES
PAGE B - 4 INSTALLATION
NOTE
The pipe submergence required may be reduced
by installing a standard pipe increaser fitting at the
end of the suction line. The larger opening size will
reduce the inlet velocity. Calculate the required
submergence using the following formula based
on the increased opening size (area or diameter).
Figure 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
A check valve in the discharge line is normally rec­
ommended, but it is not necessary in low dis­
charge head applications.
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.
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 mecessary to permit the escape of air to at­
mosphere during initial priming or in the repriming
cycle, install a bypass line between th epump and
the discharge check valve. The bypass line should
be sized so that it does not affect pump discharge
capacity.
It is recommended that a Gorman‐Rupp Automatic
Air Release Valve be installed in the bypass line.