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5-1.Piping System for The Centrifugal Pump:
The successful working of a centrifugal pump depends upon the correct selection layout of its piping system. An extreme care should always be taken in selecting the sizes of the pipes and their arrangement. In general a centrifugal pump has:
a) Suction Pipe.
b) Delivery Pipe.
a) Suction Pipe:
The suction pipe of a centrifugal pump plays an important role in the successful and smooth working of the pump. A poorly designed suction pipe cause insufficient net positive suction head (NPSH), vibration, noise, water hammer, excessive wear, etc. While laying the pipe, a great care should be taken to make it air tight. A strainer foot-valve is connected at the inlet of the pump is limited to avoid cavitations, it is therefore essential that the losses in the suction pipe should be as small as possible, for this purpose bends in the suction pipe are avoided and its diameter is often kept larger. Sometimes, to reduce the axial thrust, the suction pipe is branched into two parts and the liquid is allowed to enter the impeller from sides, such a pump is called double suction pump.
b) Delivery Pipe
c) A check valve is provided in the delivery pipe near the pump, in order to protect the pump from hammer and also to regulate the discharge from the pump. The size and length of the delivery pipe depends upon the requirement.
d) Manometric Head:
It is an important term, in the field of centrifugal pumps, and may be defined in any one of the following four ways:
1-the manometric head is the actual head against which the pump has to work.