What are the working points of positive displacement pumps?
发布时间：2022-03-28 14:34:00 点击：
Answer: The positive displacement pump relies on the periodic change of the volume of the sealed working space containing the liquid to periodically transfer the energy to the liquid, so that the pressure of the liquid increases until the liquid is forcibly discharged.
The working characteristics of the positive displacement pump are:
1) Flow and pressure (head) pulsation;
2) It has self-priming ability, but be sure to open the outlet valve before starting;
3. It can transport viscous media with little change in efficiency, and it can also transport media with a certain amount of air
4) As the viscosity of the liquid increases and the gas content increases, the flow rate and efficiency of the pump decrease;
5) The positive displacement pump must be equipped with a safety valve;
6) The flow rate cannot be adjusted by the outlet control valve, and the methods of bypass adjustment, speed adjustment and stroke adjustment are commonly used to adjust;
7) The theoretical flow qvr has nothing to do with the characteristics of the pipeline, but only depends on the pump itself, and the pressure provided only depends on the characteristics of the pipeline, and has nothing to do with the pump itself;
The working characteristics of the positive displacement pump are:
1) Flow and pressure (head) pulsation;
2) It has self-priming ability, but be sure to open the outlet valve before starting;
3. It can transport viscous media with little change in efficiency, and it can also transport media with a certain amount of air
4) As the viscosity of the liquid increases and the gas content increases, the flow rate and efficiency of the pump decrease;
5) The positive displacement pump must be equipped with a safety valve;
6) The flow rate cannot be adjusted by the outlet control valve, and the methods of bypass adjustment, speed adjustment and stroke adjustment are commonly used to adjust;
7) The theoretical flow qvr has nothing to do with the characteristics of the pipeline, but only depends on the pump itself, and the pressure provided only depends on the characteristics of the pipeline, and has nothing to do with the pump itself;
8) As the discharge pressure increases, the internal leakage loss of the pump increases, so the actual flow of the pump also decreases slightly with the increase of pressure;
9) The shaft power increases with the increase of the discharge pressure, and the efficiency of the pump also increases, but after the pressure exceeds the rated value, the efficiency will decrease due to the increase of internal leakage.
