1.Water filling :
In particular, small axial flow pump horizontal axial flow pump or small vertical axial flow pump are installed in the position above the water, so it is in the start before the pump shell and the suction bell also must be filled with water. Similarly, in the presence of air, the pump and the suction tube can not form a vacuum. Therefore. Generally the other one to several sets of electric vacuum pump, they will use the pump shell and the suction bell mouth pumping out the air in the vacuum, in order to achieve the purpose of water filling.
Large vertical axial flow pump, usually installed in the position below the surface, so the pump shell and the impeller and the suction bell are immersed in a liquid, without prior to the start of the first special it is full of water, therefore, no pumping device, can quickly start, this is one of the characteristics of the axial flow pump. Automatic startup is an advantage.
Axial flow pump start-up operation sequence and method basically and centrifugal pump start-up operation sequence and method of the same. However, it must be pointed out that. Various types of centrifugal pump start. Its export valve is closed, and the start of the axial flow pump, the outlet valve should be open. This is because the flow in axial flow pump is equal to zero, the power is greater than the rated power of two times or two times; at the same time, it will exacerbate the cavitation, which is due to flow into the quarrel deviation blade angle increases, causing off flow phenomenon, only in more than 60% greater than the maximum efficiency point of this phenomenon to disappear.
The stop operation of the axial flow pump is basically the same as that of the centrifugal pump.