Standards for leak testing of air valves in reciprocating compressors

It is more appropriate to determine this based on the size of the air valve and whether it is a mesh valve or a ring valve. It seems no specific standards have been established; my personal suggestion is that during leak testing, intermittent dripping should be allowed within 5 minutes. For small valves (with an outer diameter of 100 mm), the number of drops per minute should be around 10. As for other cases, it’s better for LZ to determine the appropriate value based on the small valves. With high requirements, it is possible to achieve almost no leakage from small valves, but this is generally not achievable with large air valves. This post was last edited by gql on 2007-10-25 11:45]

My valve diameters are 250mm and 380mm

My valve diameters are 250mm and 380mm

It seems that during installation, the air valves are checked using kerosene, and leaks are not allowed; there are relevant regulations – look for them on forums.

Now, most valve manufacturers require that cleaning oils such as kerosene and diesel not be used for leak testing; with the advancement of technology and the emergence of new materials and designs, using kerosene to test valve leaks is no longer appropriate. Here are two examples to illustrate this: 1– For valves with non-metallic disc (ring) seals, testing for leaks using kerosene is likely to result in a failure. However, if it passes the airtightness test, there will be no problems when the valve is put into operation. The sealing of the valve disc is achieved through pressure differences, and the airtightness test simulates this condition by assessing the valve disc’s ability to seal gases under such pressure differences. 2- For some gas valves with special structures, such as those that have spacers like lift gaskets between the valve disc and the valve seat, if kerosene is used for leak detection, the middle ring of the gas valve will always show leaks. But if the airtightness test is successful, it should be ready for installation and use. In short, testing the leakage rate of gas valves using a hermetic device is practical and reliable, while the kerosene testing method is no longer suitable for today’s technological advancements. Of course, there is no valve that is leak-proof. As long as the leakage amount is below the allowable value, it is considered qualified. The airtightness testing method can quantitatively determine the leakage rate of air valves, whereas the kerosene testing method cannot.

A dedicated airtightness testing device is of course the best option, but for most small enterprises in China, which already have few compressors and a limited number of air valves, it is impractical to acquire such a device or send the products to professional manufacturers for testing; thus, makeshift solutions have to be used. :lol

During installation, check the air valve using kerosene; 3 drops per minute are allowed

It is difficult to achieve a leakage of 3 drops per minute for air valves with diameters of 250 mm and 380 mm

Friends, don’t just focus on studying textbooks or manuals; you can fix any air valve leakage issues within 2 to 4 hours by using compressed air. Do we still need to consider N years? That’s so stupid! ! ! ! :L :'( :funk:

We are a maintenance company, and we don’t repair gas valves very often; therefore, we don’t have the necessary equipment. I could create my own set of simulation testing equipment, but that would require investment. I only need to repair a few gas valves temporarily, and it is the client’s standards that drive me to seek compliance with certain regulations. There are relevant standards specified in HGJ206-92 for small and medium-sized piston compressors, but the gas valves we use are larger than those specified in these standards. According to those standards, when there are 4 valve leaf rings, the leakage rate should be 64 drops every five minutes. We’re not just following rules mechanically; we can ensure that the gas valves function properly. However, working for foreign companies makes it difficult to meet such standards