1. The influence of condensed water:
Condensate has an insignificant position in a multi-stage vacuum pump. In order to ensure that the condensate can fully condense the steam, the partial pressure of water vapor in the discharge pressure of the vacuum pump must be higher than its corresponding full vapor pressure, so the temperature of the condensate must also be Below the full temperature under this pressure, the normal operation of the pump body can be guaranteed. In addition, the condensing power of the condenser is also very important. The poor condensing effect of the condenser will cause the steam to directly enter the next stage pump because it is too late to condense, increase the load of the subsequent stage pump, and affect the pumping ability of the pump. For this reason, the inlet temperature of the condensate, the flow rate and the operation of the condenser have a great influence on the function of the pump.

2.The influence of steam:
The steam eruption vacuum pump uses over-saturated steam as the working medium, and the condition of the steam has a decisive influence on the function of the pump. Wet steam not only affects the function of the pump, but also corrodes the steam nozzle, adding the amount of steam to the pump, making the pump's operating conditions unstable.

3. The impact of internal leakage:
During the entire liquid steel disposal process, the vacuum degree of the system is continuously increasing with the reduction of the gas outgas of the liquid steel. In the early stage of liquid steel disposal, the vacuum of the system is low, and the amount of gas released is large, and the pumping capacity of the fore-stage pump is required. Usually, multiple pumps in parallel are used to increase the pumping capacity of the system. When the vacuum of the system continues to increase, the outgassing volume of the system is also reduced. In order to reduce steam consumption and save energy, it is necessary to close several of the front-stage parallel pumps. The 3A, 3B, 4A, and 4B in the pump layout diagram are called backing pumps, or pre-pumps, and B1, B2 are called booster pumps. When the full pump is put in, B1, B2 are open, and 3B, 4B pumps are closed. In the layout diagram, it can be seen that the system is connected with the 3B and 4B pumps through two check valves. If the two check valves are not in place, there may be leakage, which will affect the ability of the system, especially the leakage of the valve. A system short circuit is formed, which makes the upper-stage pump unable to operate normally due to excessive back pressure, presenting a double vacuum appearance. Secondly, the nozzle of the vacuum pump is composed of two parts. The two parts are connected by flanges. Regarding the vacuum pump with the connecting flange in the pump body, if the connection is leaked due to sealing and other reasons, it will also give the pump function. Form an impact.

4. The influence of pump body layout:
Regarding the single-stage vacuum pump, the simple wear part is the steam nozzle. After the nozzle is worn, it will not only affect the function of the pump, but also increase the operating cost of the system.

5. Environmental impact:
The environmental impact mainly refers to the pollution of the system by the pumped gas. During the disposal of the molten steel, the molten steel will release a lot of gas. At the same time, a part of fine oxide powder and other small particles will be sucked into the vacuum pump, and these small particles will accumulate. Adhere to the pump body, reduce the conductance of the pumping pipeline, extend the pumping time, and reduce the pumping function of the pump.

After a long period of theoretical exploration, the major influences on the function of the pump are: internal leakage, the influence of steam, and the influence of the layout of the pump.