1.Motor rotation :
Because the connection elements will cause the motor turning request and pump is contrary to the general practice, so start to look into the steering pump, if the steering reaction, should be on the motor terminal wires can be arbitrary AC.
2.Point to large flow low head offset :
Under normal circumstances, the centrifugal pump has a series of downward curve, flow with the head to reduce the gradual change. In the operation process, because some elements of the pump pressure is reduced, the working point of the pump equipment passively follow the curve shift to the low lift and large flow rate, so it will form a head lower, originally this is because changes outside elements such as equipment and structure, and the pump itself did not have a special relationship. At this time only to add pump back pressure, such as the closure of a point of export valve can handle the question.
3.Speed reduction:
Is an important factor affecting the pump impeller diameter and pump speed, in other conditions unchanged, two times the distance and speed of the pump is proportional to the contact effect of visible speed on the head is very large, sometimes because of some external factors that reduce the pump speed will be reduced accordingly. Pump head. Should check the speed of the pump at the moment, if indeed speed does not work, should view elements, reasonable treatment.
4.Imported attack cavitation:
If the pump suction inlet pressure is too low, lower than the pumping medium saturated vapor pressure, cavitation will constitute. Should look at the import pipeline system at the moment there is no obstruction or inlet valve opening is too small, or may progress to the level of the tank suction tank.
5.Episodes of internal leakage:
When the pump stop and some more than some space planning scale, will cause the internal leak, reduced to reflect the pump discharge pressure, such as impeller ring gap, the gap between the level of multistage pump. At the moment should be the corresponding dismantling of the components of the gap is too large to repair or replace.
6.Impeller duct obstruction:
If some impeller flow blockage, will affect the work of the impeller, the pressure decreases. Therefore need to remove the pump to see the removal of foreign bodies. In order to avoid this question again, if necessary, can be added to the pump inlet filtration equipment.
