Any equipment has its working efficiency, and people calculate the working efficiency of vacuum pump by calculating the suction volume and speed of vacuum pump. The pumping rate of the vacuum pump is well understood, that is, the time consumed in the process of pumping the air in the container to the point where it cannot be pumped. This price comparison is easy to calculate, as long as the time required for the vacuum pump from operation to stop operation is observed. As for its air extraction, it can not be obtained through observation, but needs to be calculated. If the vacuum pump is pumping at a uniform speed, the time and rate can be achieved, but most vacuum pumps do not work at a uniform speed, especially at the beginning of operation, there must be an acceleration process. A variety of methods for calculating the extraction volume are provided here. The first method is to determine the amount of air pumped by the vacuum pump by measuring the reduction of air in the container, which is an equal relationship. The air lacking in the container is absorbed by the vacuum pump. The air capacity here can be tested before pumping, and then measured after pumping. The result is the subtraction of the two. Of course, such calculation may cause errors, because the gas in the container may not be in a sealed environment at first, and the gas content here may be affected by other components. Moreover, this method is not a commonly used detection method, because it needs multiple measurements, which will increase and decrease the workload. Some say that the extraction volume can be calculated according to the extraction rate. In fact, the pumping rate is also a quantity that needs to be calculated, and the results obtained from the machine manual are also obtained through precise calculation. There is a vacuum chamber in the vacuum pump. Its volume determines the volume of air that the vacuum pump can absorb, so the pumping rate of the vacuum pump can be calculated by measuring it. Generally, the size of a part of the same brand and model is fixed, and the volume has been determined since the end of production. Then measure the pressure in the vacuum chamber and compare the pressure changes before and after. The speed of pressure change is positively correlated with the pumping rate, and the results can be measured. If you want to know a certain period of time, the air extraction of the machine can be calculated. Consumers do not need to calculate this value by themselves, because it has been measured by technicians when leaving the factory. This can be used as the reference data for everyone to choose products. If the pumping capacity of the vacuum pump is large, the pumping rate will be faster.