Centrifugal pump flow, why can be adjusted through the outlet valve? Can the flow of the reciprocating pump be adjusted in the same way?. Why
Reciprocating pump is a positive displacement pump, the volume change of flow is the unit of time, constant flow speed constant, can not rely on increased resistance to change the flow resistance increase is only leaked, only small changes in flow.
First of all, we know that pump according to the principle of work is divided into speed and volume type, centrifugal pumps are speed type, and reciprocating pumps are volume type.The centrifugal pump can adjust the flow through the outlet valve and outlet valve opening can determine the pump flow and head performance curve parameters such as specific relationship between the outlet flow and pressure can be provided by the data pump manufacturers endplate that even close the outlet valve of the pump pressure will also have a fixed value, but not allow zero flow pump operation, vibration caused by damage to the pump on the mechanical seal is not good and so easy to cavitation, set the minimum reflux line.
Centrifugal pump, and is a very common method of centrifugal pump, flow with the head (or pressure) increases, off a small valve resistance increases, the pump head should be increased, then the flow decreased, whereas open valve flow increase
