SBI/SBN Vertical Multistage Centrifugal Pumps
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8.
If it is necessary to increase the diameter of the suction pipe, place an eccentric reducer between the
check valve and the flexible pipe section.
9.
Using elbows will increase the flow resistance. Long radius bends will result in less flow resistance.
10.
The piping must have a level or positive gradient to prevent the formation of air pockets.
11.
The diameter of the drop pipe must be bigger than the diameter of the pump’s suction port.
12.
Use a foot valve in case of negative suction head.
13.
Size pump for correct head.
14.
Place the intake of the suction pipe so that the footvalve is always submerged to prevent entry of air.
15.
Install a compound gauge at the pump suction and a pressure gauge at the pump discharge.
6. Electrical connection
—
All electrical connection should be in accordance with the local regulations and made by a qualified electrician.
— Make sure that the supply voltages and frequencies, and phase are suitable for the motor used.
— Before proceeding, make sure that all the connections are grounded and well insulated.
— Overload protection should be provided.
— To connect, proceed as shown on the inside of the terminal board cover.
— The terminal box can be turned to four positions.
— Check the direction of rotation (Three-phase motor only).
— Make sure that the controls are properly grounded.
— To avoid the possibility of dry running, we strongly recommend installing dry running protection.
7. Start-up
T
he pump and suction pipe should be filled with the liquid to be pumped before start-up to prevent dry running at
start-up.
WARNING:
Dry running can damage the pump bearing and shaft seal.
7.1 Operation
— Start the pump and check the direction of rotation of the motor (Three –Phase motors).
— Start the pump, keeping the on-off valve of the discharge side of the pump closed. Then, open the on-
off valve slowly. The pump must run smoothly and noiselessly. If not, then it may be necessary re-prime
the pump.
— Check the current drawn by the motor. If necessary, adjust the setting of the thermal relay.
— Any air pockets trapped inside the pump may be released by adjusting the air screw.
