Although the three-screw pump has many advantages, if it is not properly selected, it not only can not get a satisfactory operation result, but also causes noise and vibration of the pump and even seriously damages internal parts of the pump so that the pump system can not work normally. Therefore, Selection of personnel should be cautious and careful consideration, a reasonable selection, if necessary, should I plant technical advice. Three screw pump selection, to be as detailed as possible to understand the conditions of the pump, in addition to the operating parameters, such as flow, pressure needs to be clear, the characteristics of the transmission medium such as media corrosivity, gas content, solid solution containing the ratio And the size of the solid particles, as well as the medium temperature, viscosity, specific gravity, corrosive materials such as pumping equipment and suction conditions, installation conditions should be understood, according to our experience, three screw pump selection should pay attention to the following Point: 1. Pump speed selection 1.1 to determine the transmission medium viscosity and pump speed range: high viscosity medium, the pump should be selected low speed, if the viscosity is low, the corresponding choice of high speed: medium viscosity> 20 ° E , For large size pump (main rod diameter 60mm and above), the speed should be 970rpm or 720rpm. If the viscosity is higher (viscosity> 80 ° E), such as viscose, the speed can be reduced, 200-500rpm is recommended; For small pump sizes, medium speeds> 14 ° or 970 rpm for medium viscosities> 20 ° E and lower speeds for higher viscosities (> 80 ° E), 300- 600rpm; 1.2 As the pump speed is higher, in the same performance parameters, the smaller the pump size, but because of high speed, high friction power, pump wear large, short life, if the lubrication of the transmission medium is relatively poor Or contain trace impurities, should choose a lower speed, so that the pump to maintain a longer life, recommended below 1450rpm. 2. The choice of structure according to the conditions of the installation and use of the pump reference to the three screw pump series and type, in principle: 2.1 conveying lubricated oil, the temperature below 80 ° C select the built-in bearing structure of the pump; 2.2 temperature exceeds 80 ° C or the transmission medium poor lubrication, the choice of external bearing structure of the pump; 2.3 conveying poor mobility, high viscosity medium or medium need to heat or heat transmission medium selection double-layer structure of the pump heat pump; 2.4 high temperature Transportation, should choose the pump made of high temperature materials, please contact our factory. 3. pump material combination of choice: see the material combination. 4. Pump suction capacity can be found in our factory sample NPSHr or [HS] value. 5. matching motor matching pump selection is determined, according to the sample data can be found in the pump shaft power N, the shaft power coupled with a certain power reserve, as a basis for optional motor, the general motor power Nm should Is not less than the value obtained by multiplying the pump shaft power N by the power reserve coefficient K, and the value of K can be taken as the following table: N (KW) N50 K 1.25 1.2 1.15 1.1 In addition, the pump performance parameters In the form of a table or a specific viscosity, speed curve is given in the form of performance, the required pump performance sometimes can not be read directly, then the following principles can be roughly estimated, if more accurate data can consult professionals. Three screw pump flow, pressure in the same speed, viscosity is approximately linear relationship, the higher the pressure, the smaller the flow. The same viscosity, pressure, pump flow and speed is approximately proportional to. The same speed, viscosity, shaft power and pressure is approximately proportional. The same viscosity, pressure, shaft power and speed is approximately proportional. As the viscosity increases, both flow and shaft power increase, but because of the complex relationship between them, consult a specialist if necessary. As long as the proper selection, maintenance and reasonable, three screw pump can ensure satisfactory operation.
Plastic Grilles,Plastic Return Air Grille,Plastic Air Vent Grilles,Plastic Ventilation Grilles
Guangzhou Jointair Co., Ltd. , https://www.jointair.cn