The air valves of piston compressors are very prone to damage! !

There are several reasons for valve damage: 1. If the installation is incorrect and the gap is not set properly, it should be corrected according to the drawings. 2. Metal fragments or other debris may fall between the valve seat and the valve disc, preventing a proper seal and resulting in air leakage. This affects not only the displacement but also the changes in interstage pressure and temperature ； Leakage occurs due to a poor fit between the valve seat and the valve disc, which affects the exhaust volume. One reason is a manufacturing defect, such as warping of the valve disc; the other reason is leakage resulting from severe wear between the valve seat and the valve disc. 3. The spring force of the gas valve is not well matched with the gas force. Excessive elasticity causes the valve disc to open slowly, while too weak elasticity results in the valve disc not closing promptly. These issues not only affect the volume of air flow but also impact power output, as well as the lifespan of the valve disc and springs. At the same time, it will also affect changes in gas pressure and temperature. 4. The clamping force of the pressure valve is inappropriate. If the clamping force is too low, air leakage will occur; on the other hand, if it’s too high, it can cause the valve cover to deform or get damaged. The clamping force can generally be calculated using the formula: p = kπ/4 D²P², where D is the diameter of the valve chamber, P₂ is the maximum gas pressure, and K is a value greater than 1, typically ranging from 1.5 to 2.5. For low pressures, K = 1.5 to 2.0, while for high pressures, K = 1.5 to 2.5. Choosing K in this way has proven to be effective in practice. If there is a fault with the air valve, the valve cover will inevitably heat up, and the pressure will also be abnormal.

The air valve is itself a wear-prone component of piston-type air compressors, and its damage is normal; what’s important is how long it was in use before it failed. Generally, the most common spare parts needed for such air compressors are air valves. If you know how to adjust and sharpen them as mentioned, it can save a lot of money.

It’s already quite comprehensive, but here are a few additional points: 1\ The material of the valve disc must be chosen carefully, ensuring it is suitable for the medium being transported. 2\ The lift distance of the valve disc must meet the required standards. 3\ The springs used should be appropriate. Additionally, it is recommended to use advanced valve assemblies to solve these problems; for example, the Junzhun mushroom valve, which has a long service life and can address the issues mentioned by the original poster

Sometimes it is also necessary to be careful not to have liquid present during the processing steps

The air valve is itself a wear-prone component of piston air compressors, and its damage is normal; what’s important is how long it was in use before it failed! And then there’s the amount of impurities in the gas! The valve seats can be ground by oneself! ! ! !

The experts upstairs have all explained the reasons for the design selection very clearly! If the design and selection of the air valve are correct, then it’s necessary to check whether the air valve is installed properly. Valves and springs are considered wear-prone components; usually, abnormal operation of a valve is caused by a broken spring or severe wear of the valve disc! Wear around the valve disc is normal! Also, consider the incoming air to the compressor – whether its composition contains excessive impurities. Remove the pre-filter of the compressor and check it!

In my high-pressure compressor (with an outlet pressure of 20 MPa), failures at the inlets and outlets of various sections used to occur quite frequently. The main reasons for these failures were as follows: 1. The spring of a certain valve broke, and the fragments from this broken spring caused indentations on the sealing surfaces of the valves downstream, leading to air leakage. 2. When the piston rings broke, their fragments got stuck in the inlet and outlet valve elements, resulting in those sections not functioning for a short period of time, which in turn triggered an automatic shutdown of the unit. To address this issue, Helbig was called in by the workshop; they improved the faulty inlet and outlet valves as well as the piston rings, and replaced them once a year during maintenance activities. This approach enabled the unit to meet the requirement of operating for 8,000 hours continuously. (I state the following absolutely not to promote Holbig)

The use of PEEK mesh valve discs in the low-pressure section can effectively extend operational time.

Thank you all for your valuable suggestions! ! ! ! ! ! ! !