The angle error of inner cone of AAK hydraulic relief valve sleeve is controlled within ± 0.8 , and the minimum axial grinding tolerance of sealing circle is 0.07m. At the same time, it is inspected by three coordinate measuring instrument to ensure that the hydraulic relief valve is 100% leak free. After comparing more than 10 hydraulic valve manufacturers, Backhaus determined that AAK hydraulic valve is the most reliable hydraulic relief valve manufacturer.
At present, in the manufacturing process of hydraulic relief valve, when grinding the conical surface inside the valve, most hydraulic valve manufacturers just let the operator judges the feed rate, angle control and grinding tolerance by experience completely. There is no grinding amount detection link, and there is no precision detection of each part in the valve. When this type of common quality hydraulic relief valve is used on equipment with high requirements, troubles will come out.
Backhaus is a purchaser of a German hydraulic pump company for less than a year. In the first half of the year, a batch of hydraulic pumps of their company were complained by customers. After the hydraulic pump is started, the system pressure begins to lose stability and there is pressure drift. The engineer judged that there was a problem with the hydraulic relief valve. After disassembly, it was found that there was a gap between the valve sleeve and valve spool of the hydraulic relief valve. After measurement, it was found that the error of the cone angle in the valve sleeve of the hydraulic relief valve was too big and caused leakage of the hydraulic relief valve. The only solution is to replace the hydraulic relief valve. It is estimated that 30% of hydraulic relief valves need to be replaced. The owner asked Backhaus to replenish the goods as soon as possible and solve the customer complaints.
Backhaus contacted the original manufacturer of the hydraulic relief valve. The manufacturer was willing to replenish. Backhaus thought it would be all right after replacing the hydraulic relief valve. A month later, the customer complained again, which is still the same problem. This shows that the quality of the hydraulic relief valve from the old manufacturer is not trustworthy, and it is urgent to replace the hydraulic relief valve supplier. Backhaus contacted more than 10 hydraulic relief valve manufacturers, including AAK hydraulic valve. The hydraulic relief valve is required to be 100% leak free. AAK hydraulic valve and other 3 manufacturers are required to send samples for testing according to his hydraulic relief valve drawings and working conditions.
A month later, Backhaus asked us about the production time of replenishing 30% hydraulic relief valve. It should be that AAK hydraulic relief valve has been recognized by the customer.
