The hydraulic check valve leaked after 3 months of use. After AAK redesigned it,

At the beginning of last year, Lawrence sent an email to ask for help. He is a purchaser of a hydraulic equipment company in Italy and has cooperated with AAK for 2 or 3 years. Almost all of the orders are a small number of hydraulic check valves with high requirements. When encountering problems, he always asks for help from AAK, and AAK is also happy to help him. After several rounds of email communication, it turned out that the power unit for controlling the hydraulic lifting column produced by their company had a customer complaint 3 months after sales. Their engineers found a leak on the valve block of the power unit, that is, around the valve hole equipped with the hydraulic pilot operated check valve. It is preliminarily judged that the leakage should be caused by the wear of the seal of the hydraulic pilot operated check valve. However, after dismantling the hydraulic pilot operated check valve, it is found that the sealing ring is intact.

After Lawrence communicated with the original manufacturer of hydraulic pilot operated check valve, they both thought that there should be no problem with the hydraulic pilot operated check valve or valve block, because the test data before shipping were qualified. The leakage problem should be caused by the wrong operation of the installation personnel of their company. Lawrence seemed to understand because it is true that the test result of the hydraulic pilot operated check valve originally shipped was OK. Lawrence asked their engineers to reinstall it. As a result, it worked normally and everyone thought the problem had been solved. But 3 months later, the same problem happened again, and the customer could not accept and requested to return goods. The boss was very angry and asked Lawrence and the engineer to completely solve the leakage problem of the hydraulic pilot operated check valve. This is why Lawrence emailed to AAK for help.

AAK engineers analyzed according to the valve block integration diagram and the drawing of hydraulic pilot operated check valve provided by Lawrence. There is an assumption that the frequent vibration of the power unit of the hydraulic lifting column affects the stability of the installation of the hydraulic pilot check valve. Following this idea, it is found that the hole depth of the threaded socket integrated with the valve is not enough, which leads to the loosening of the jack position of the hydraulic pilot operated check valve. This problem can only be solved by adjusting the depth of the jack, increasing the thread torque of the hydraulic pilot operated check valve and increasing the bonding area between the valve and the hole. The next day I emailed Lawrence the idea of our engineer's. If we want to verify this idea, we can only make samples. One month later, AAK sent the redesigned hydraulic pilot operated check valve and integrated valve block to Lawrence.

Last week, Lawrence sent an email saying that after the hydraulic pilot operated check valve and valve block redesigned by AAK were installed on the equipment, so far, the hydraulic lifting column has been used without abnormality.