Recently, some netizens left a message to Xiaobian asking about the cause of the explosion of the exhaust pipe of the vacuum pump. By sorting out relevant information and consulting relevant experts, Xiaobian summarized the following treatment methods, hoping to help everyone.

1. Filtration

In the process of vacuum pump absorbing air, a small amount of some materials and residual liquid will be sucked into the valve plate of the pump, at the same time, some lubricating oil will be stuck on the valve plate of the pump. These substances are carbonized at high temperature for a long time to form carbon deposition. Under certain conditions, when they meet the mixture of combustible gases, they are easy to cause deflagration and release through the exhaust pipe to form detonation. In order to eliminate this phenomenon, a filter device can be installed on the front gas pipeline of the pump to filter the dust or residual liquid, and the filtering facilities should be cleaned regularly to ensure the good performance of the device. At the same time, the whole pump body should be maintained and the valve plate should be cleaned in time. Practice has proved that this work is best carried out every three months.

2. Cooling

Due to the reciprocating motion of the piston of the vacuum pump in the cylinder, the temperature of the pump body is too high, which provides conditions for the carbonization of materials, and finally leads to accidents. In order to avoid the occurrence of this situation, the operator is required to open the cooling system of the pump before starting the pump, and ensure that the water pipeline in and out of the system is unobstructed. The main causes of the accident are that the operator has no strong sense of responsibility, violates the operation regulations and is negligent.

3. Washing and buffering

Adding water washing and buffer tank in front of the vacuum pump can effectively eliminate the residual liquid inhaled, and has a certain cooling effect on the mixed air. However, in the actual work, there are often two phenomena as follows: first, when the residual liquid in the tank is small, a small amount of feed liquid will be sucked into the pump body, and the material will be carbonized at high temperature; second, when the residual liquid is large, if it is not discharged in time, the vacuum pump is likely to inhale the liquid and flush the pump, resulting in large equipment accidents. Therefore, in the production process, workers need to have a strong sense of responsibility, timely discharge of residual liquid, to avoid accidents.

4. Prevention of blocked or blocked exhaust pipe

If the exhaust pipe is blocked or blocked, the mixed gas containing methanol vapor can not be discharged in time. If it accumulates to a certain extent, it will leak out forcefully, explode or even explode. There are many reasons for this phenomenon, which may be due to design defects, resulting in relatively low position of the exhaust pipe and water or oil accumulation in the pipe; it may also be due to some human factors or natural factors, for example, the outlet valve is not opened or not opened enough, and the rain cover collapses, resulting in poor exhaust. Therefore, when designing the position of vacuum pump, the position of main exhaust pipe and the design of related accessories are also more important.

5. Tail gas control

To prevent the explosion of vacuum pump and strengthen the control of exhaust gas is a very important safety technical measure. The exhaust gas from vacuum pump is mainly mixed gas containing a large amount of methanol vapor. According to the physicochemical characteristics and working practice of Jiazui, one or several condensing devices (ice salt water of about - 10 ℃ is generally used) before the buffer tank to condense the mixed gas; Secondly, a condensing device is also installed on the exhaust pipe to condense the final exhaust gas, so as to reduce the concentration of methanol vapor in the exhaust gas to below the lower explosion limit, and at the same time, it can also protect the environment. However, in the process of condensation, it is necessary to properly control the flow of condensate water. If the flow rate is too small, it is easy to cause poor condensation effect. If the flow rate is too large, it is easy to cause blockage of the pipeline due to strong condensation and affect the vacuum effect.

To sum up, these safety measures can effectively avoid the explosion of vacuum pump. Of course, in order to ensure the real safe operation of vacuum pump, in addition to taking these safety technical measures, we must also make efforts to improve the operation skills and safety quality of operators from the aspects of people, materials and management.