Pump is a kind of energy conversion machine, the energy conversion process inevitably accompanied by the loss of energy, and a measure of the efficiency is the conversion, how to improve the efficiency of the pump and reduce energy loss?Must be understood within the pump energy loss.Inside the pump energy loss mainly includes the following three aspects.
1. The mechanical loss
Mainly liquid and the impeller external surface of the plate before and after and the pump cavity of the friction loss (also called disc loss)
Test shows that disc loss is the direct ratio three times of the speed, and the direct ratio five times of impeller diameter.Therefore, the larger the impeller diameter, the loss is larger.But under the given head, with the improvement of speed, accordingly to reduce the impeller diameter, loss of disc into five power was down, so, with the increase of rotational speed, disk loss does not increase, instead of falling, this is one of the reasons for the development of high speed pump.
Part of the liquid by the impeller leakage through impeller sealing ring clearance returned to the impeller inlet can not effectively use and make loss.As a result, the clearance between the sealing ring should be as small as possible, but due to machining and assembly, the gap too small may be forming eccentric wear or jammed, national standards for various types of pump clearance made specific provisions.
Pump flow section (from inlet to outlet) liquid fluid must have a velocity and direction change caused by the loss, the two parts is the hydraulic loss.To reduce this part of the loss, in addition to improve the flow components, try choosing excellent hydraulic model.
Vibration can be felt, with the hand touch the motor end, pump head end respectively, if only the motor vibration, may coupling, or there is something wrong with the motor bearing.
Pipeline centrifugal pump Import uneven distribution of flow velocity and pressure is uneven distribution , pump working liquid pressure pulsation, import and export flow, bias current and flow, the working condition of quota and the various causes of water pump cavitation, etc., are common causes of pump unit vibration.
Motor is the main equipment units, the internal magnetic imbalance and other electrical system disorders, often cause vibration and noise.Test for a balanced three-phase motor runtime, check whether the power frequency is stable.