1, according to the purchase of stainless steel self-priming pump, commonly used stainless steel self-priming pump according to the principle of action is divided into the following three kinds:

    A. gas-liquid mixed type self-priming pump working process: due to the special structure of the pump body, the pump stops after the turn, the memory of the pump body has a certain amount of water, pump starts up again due to the action of the rotating impeller, inhalation pipe air and water are fully mixed, and is discharged into the gas water separation chamber, gas water separation chamber and the upper part of the gas overflow, the lower part of the water return impeller, re and suction pipe residual air mixed until the pump and suction tube gas discharge, the self-priming is completed, and the normal pumping.

   B. water wheel self-priming pump is water ring round the pump impeller and the combination in a shell, with water ring round the gas discharge to achieve self absorption. When the pump to work, can cut off the water through the valve and pump impeller ring round channel, and release the water within the liquid ring round.

   C. self-priming pump, composed of centrifugal pump and jet pump (hydraulic injector), relying on the injection device, in the nozzle caused by vacuum suction to achieve.

   2, should be properly selected pump. After determining the type of pump to consider their economic performance, with particular attention to the choice of pump head and flow and the supporting power. Must pay attention to and pump signs marked on the head (total head) and the use of water head (the actual head) is different, which is due to the flow of water through pipes and pipe near there will be some loss of resistance. Therefore, the actual head is generally lower than the total head of 20% ~ 10%, the corresponding reduction in the amount of water. Therefore, the actual use, only according to sign the note head and flow rate of 80% ~ 90% estimate, matching pumps power of choice, according to the signs indicate the power selection, in order to make the water pump start rapid and safe use, the engine power can also be slightly larger than the pump power required, generally higher than 10% is appropriate; if already have power, to buy water, can purchase by the power of the engine and the matching pumps.