Discharge lines – Gorman-Rupp Pumps V3A60-4024T 1435149 and up User Manual
Page 14
ULTRA V SERIES
OM−06266
PAGE B − 7
INSTALLATION
FLOW
DISCHARGE
LINE
SUCTION
LINE
SIGNAL CABLE
(ATTACH TO
SUCTION LINE)
SUBMERSIBLE
TRANSDUCER
(DOWNSTREAM
FROM SUCTION)
SUCTION
STRAINER
Figure 4. Typical Submersible Transducer Installation
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.
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
Self-priming pumps are not air compressors. Dur-
ing the priming cycle, air from the suction line must
be vented to atmosphere on the discharge side. If
the discharge line is open, this air will be vented
through the discharge. However, if a check valve
has been installed in the discharge line, the dis-
charge side of the pump must be opened to atmos-
pheric pressure through a bypass line installed be-
tween the pump discharge and the check valve. A
self-priming centrifugal pump will not prime if
there is sufficient static liquid head to hold the dis-
charge check valve closed.