The method of regulating the flow control of the multistage pump has three kinds of adjusting plunger or piston stroke, adjusting stroke and pump speed, in which the way of adjusting the stroke is the most widely used. The method is simple and reliable. There are three ways to adjust the stroke.
1, manual adjustment when parking: manually adjust the stroke of multistage pump when parking.
2, manual adjustment in operation: change the axial displacement in the pump operation, in order to change the radius of the crank succinctly, to achieve the purpose of adjusting the length of the stroke. The common methods are N - shaped crankshaft adjustment, L - shaped crankshaft adjustment and eccentric cam adjustment.
3, automatic regulation in operation: there are two kinds of pneumatic control and electric control. Pneumatic control is to automatically adjust the stroke by changing the pressure signal of the gas source, and the electric control is to automatically adjust the stroke by changing the electrical signal.
Under the condition of determining the metering medium and working pressure, the multistage pump can realize the two-dimensional adjustment of the output of the metering pump by adjusting the stroke length and reciprocating frequency. The import of reciprocating stroke length and frequency can be used as variable, but generally in the engineering application of stroke length as coarse variable, reciprocating frequency fine tune the variables: adjusting the stroke length to a certain value, then change its frequency to achieve fine adjustment, increase the flexibility of adjusting the metering pump. In relatively simple applications, the length of the stroke can be set manually, and the stroke frequency is only used as an adjustment variable, thus simplifying the configuration of the system.