Method 1: the opening of the outlet valve adjustment :
In this method, the pump and the outlet pipe are connected in series, its actual effect is similar to the new pump system, the maximum output pressure of the pump has not changed, but the flow curve has been damped.
Method two: bypass valve adjustment :
In this method, the valve and the pump are connected in parallel, the actual effect is similar to the new pump system, the maximum output pressure of the pump is changed, and the characteristics of the flow curve is changed, the flow curve is more close to the line.
Method three: adjusting the diameter of the impeller :
This method does not use any external components, and the flow characteristic curve varies with the diameter.
Method four: speed control:
Impeller speed change directly change the pump flow curve, the characteristics of the curve does not change, the speed decreases, the curve becomes flat, the pressure head and the maximum flow are reduced.
The overall efficiency of the pump system outlet valve adjustment and bypass adjustment methods are increased pipeline pressure loss, pump system efficiency is significantly reduced. Impeller diameter adjustment to the entire pump system efficiency is small, the speed control method basically does not affect the system efficiency, as long as the speed is not less than 50% of the normal speed.
Energy consumption level:
These four methods will be assumed by the pump output flow is adjusted from 60m³/h to 50m³/h, output power of 60m³/h for the consumption of 100% (now head of 70m), then control the flow way of several power consumption effects?
1.Outlet valve opening adjustment, energy consumption is 94%, the flow rate is low, the power consumption is large.
2.Bypass regulation, bypass valve will be reduced to 55M pressure head, which can only be achieved by increasing the flow of the pump, the result of energy consumption increased by 10%.
3.Adjust the impeller diameter, reduce the impeller diameter of the pump output flow and pressure are reduced, energy consumption reduced to 67%.
4.Speed control, speed reduction, pump flow and pressure head are reduced, energy consumption reduced to 65%.
