Single screw pump. Double screw pump. Three-screw pump and five-screw pump have their own advantages, and must be selected in the promotion and application of screw pump. Only by making full use of their own characteristics can we achieve better energy saving. Save materials. Improve efficiency or meet some special requirements.

Double screw pumps. Three screw pumps are collectively referred to as multi-screw pumps. Since the invention of multi-screw pump, it has been widely used in the original oil pump. Fuel oil. Lubricants. Power fluids. Food. Chemical and synthetic fiber pulp. There are about 1 million more screw pumps in operation. Multi-screw pump is widely used, of course, very careful in the choice. Here is how to chooseknoll double screw pump:

1. Process:

The main factor affecting the flow rate of the double screw pump is the speed of the medium. Pressure and viscosity.

When the screw pump works, a sealing cavity is formed between the two screws and the bushing, and the screw moves a sealing cavity from the inlet and outlet every week, that is, the liquid of the sealing cavity volume is discharged. In the ideal state of no leakage in the pump, the flow rate of the pump is proportional to the speed.

However, in the actual work process, the seal chamber of the pump has a certain gap, and there is a pressure difference before and after the seal chamber, so there is some liquid reflux, that is, leakage. With the increase of the pressure difference between the front and back of the sealing cavity, the leakage amount increases gradually. For different lines and structures, the size of the impact is different.

For the double screw pump, the fluid viscosity is less than the viscosity of the leaking liquid, and the leakage amount has a certain proportion to the viscosity of the medium.

2. Stress:

The working pressure of the double screw pump is determined by the outlet load, that is, the outlet resistance. The outlet resistance matches the outlet pressure of the pump. The greater the outlet resistance, the greater the working pressure. To understand the pressure, it is necessary to use the knowledge of fluid mechanics to accurately calculate the exit resistance.

3. Shaft power:

Pump shaft power is divided into hydraulic power (pressure liquid energy) and friction power two parts. For the specified pressure and flow, the hydraulic power is certain, so the factor affecting the shaft power is the friction rate.

Friction power is the part of power consumed by friction of moving parts. Obviously, the friction power increases with the increase of the working pressure difference, and the increase of the viscosity of the medium will also lead to the increase of the liquid friction power. Therefore, when selecting a matching motor, the viscosity of the medium is also a very important reference data. Especially when conveying high viscosity media, more accurate calculations are needed.

4. Suction:

The work of the pump is divided into the following stages: suction, the liquid continues to move along the suction tube; The rotating screw transfers energy to the working fluid; Output the pressure required to overcome all resistance of the output piping system.

In the above three stages, z* this is an important stage, is to ensure the suction conditions of the pump, the pump can work normally, which is an important condition for the work of the pump, otherwise cavitation will occur, that is, cause vibration. Noise and other problems.

5. Cavitation allowance:

Pump cavitation and pump speed. The lead is related to factors such as the viscosity of the pump conveying medium, and it increases with the increase of the axial speed.

The above content is knoll Kono double screw pump selection skills, Shenzhen Oudejie technology professional sales of imported knoll Kono screw pump, and committed to sales of screw pump products are new original imports, while providing our customers with quotation, selection, product information and other services.