Leo from Germany, who had been successful in the purchase of hydraulic valves, recently lost confidence in an order for hydraulic relief valves. During the test phase, when the pressure of the hydraulic relief valve sample is below 250bar, the system operates normally. Once it exceeds 250bar, the hydraulic relief valve will leak oil and the pressure will be unstable. After several debugging by their professional technicians, the oil will still leak when the pressure is high. After disassembling the hydraulic relief valves, no abnormality was found, but the O-ring was slightly scratched or the position was slightly offset, which may be the cause of oil leakage. The original hydraulic pressure relief valve manufacturer said that the O-ring material is synthetic rubber with the best anti-aging and oil resistance. It is the most suitable medium for this working condition. The assembly is also completed by 5 years of skilled workers. More new samples of hydraulic relief valves were tested, but they still leaks when the pressure is high.
Leo believes that the O-ring seal of the hydraulic relief valve is improperly assembled, so it is urgent to find a reliable hydraulic relief valve manufacturer to re-produce it, otherwise there is a risk of shipping by air. Leo contacted more than 10 factories in 3 days, but none of them guaranteed that the sealing ring will be 100% free of displacement and scratches after assembly. The customer has been pushing for the progress of the approval samples, but Leo hasn't even determined the manufacturer. How can he take it easy?
Leo started to look for new hydraulic relief valve manufacturers on Google, and noticed AAK hydraulic valve. He left a message to us: how should the synthetic rubber O-ring be assembled to make sure that there is no displacement or scratch? At the same time, it needs to make sure that when the pressure is above 250bar, the hydraulic relief valve does not leak oil, and the pressure is still stable. I told him that the disadvantage of the synthetic rubber sealing ring is that it is easy to deform under strong force, and not installed in place. As soon as the pressure is high, it will leak oil. Leo immediately sent the drawing of the hydraulic relief valve to AAK to make samples. Because we have the existing procedures for this hydraulic relief valve, 7 days later, the samples of the hydraulic relief valve were sent. 2 weeks later, Leo told me that AAK hydraulic relief valve had no oil leakage when it was pressurized to 300bar and tested continuously for 3 days.
Most of hydraulic relief valve manufacturers install the sealing ring by directly pressing it with clamps. AAK suffered similar complaints 5 years ago. We have been skilled in and improved the installation process of O-ring 3 years ago. Apply lubricant to the long shaft of the valve first to ensure that the O-ring slides without resistance. When passes through the external thread, we will use the metal guide sleeve to guide it into the O-ring groove instead of forcing it in. After the O-ring is put into the groove and the O-ring is restored to 100%, check the gap to ensure that there is no displacement or scratch, and then install it into the valve body. When it is installed in the valve body, it should also be coated with lubricant to rotate and insert slowly, and the O-ring will not be affected.
Yesterday, Leo sent a photo of him in the bar and told me that this was the most relaxing time in the past month for him.
AAK hydraulic relief valve, O-ring is assembled with unique skills, no oil leakage, you can also have a small try!
AAK HYDRAULIC VALVES (271) 2022-06-28