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". Pump Selection and Specification$n overview of and understanding of the differentiation etween Centrifugal Pumpand Positive Displacement Pump emphasised in term of Performance, %low Rateand &fficiency:

%ig '()* Charts represents Performance, %low rate + &fficiency.

#. CaitationThe term Cavitation implies a dynamic process of formation of ules inside theli"uid, their growth and suse"uent collapse as the li"uid flows through the pump-The concept of cavitation and its effects on pumps e#emplified through video sessionin the classroom.

%ig '()* mpeller Cavitation Regions.

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There are two types of ule formation inside the li"uid:

/.0. $aporous Caitation:vaporous cavitation is a common form ofcavitation found in process plants. 1enerally,resulted from insufficiency of the availale.

#.2. %aseous Caitation:1as ules are formed due to the presence of dissolved gases in the li"uidthat eing pumped2 generally air.

#.". Suction Caitation:Suction cavitation occurs when the pump suction is under a low*pressure3high*vacuum condition where the li"uid turns into a vapor at the eyeof the pump impeller.

#.#. !isc&ar'e Caitation:Discharge cavitation occurs when the pump discharge pressure is e#tremelyhigh, normally occurring in a pump that is running at less than 045 of its estefficiency point.

(. Pump Sealin'Sealing of pumps outlined during the course as a 6ey role in pump maintenance.

Soft Pac6ing

Mechanical Seal

Mechanical seal Classification:

%ig '()* Cavitation Steps

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Pusher Mechanical Seal 7on*Pusher Mechanical Seal