Generally speaking, the inlet and outlet of rotary positive displacement pumps such as screw pumps can be reversed, that is to say, the inlet and outlet of the pump can be interchanged theoretically, but there are several problems in this before the product leaves the factory. Need to solve:
1. Sealing problem of screw pump: Generally, manufacturers design the sealing scheme of the pump according to one rotation direction. If the inlet and outlet of the pump need to be changed, the rotation direction of the rotor needs to be changed, so the sealing scheme inside the pump chamber must be changed, otherwise, the seal will fail. Work;
2. Force balance system: A small number of rotary positive displacement pumps need to design a force balance system, such as a three-screw pump, so it is not possible to change the direction of the inlet and outlet at will;
3. The diameter of the inlet and outlet pipes of screw pumps. Generally, the inlet of positive displacement pumps is designed to be larger than the outlet. Changing the direction of the inlet and outlet is not only the matching of pipe flanges but also whether the necessary NPSH of the pump is satisfied;
So in general, unless special requirements are made before ordering, most rotary positive displacement pumps are not recommended to be interchangeable with import and export.