With 3 Tricks to Strengthen the Valve Spool, the service life of AAK Hydraulic C

Blade is from Canada. He has been purchasing hydraulic components successfully for 3 years. Unexpectedly, a hydraulic cartridge directional control valve stumped him. In the second half of last year, a batch of their hydraulic logistics lifts were complained by customers, some of them were unable to work, probably because the hydraulic cartridge directional control valve leaked. After checking, it was found that the valve spool was deformed. The original manufacturer of the hydraulic cartridge directional control valves said that it had been shipped for 9 months, and some exceptions were inevitable. It is possible that the internal stress of the valve spool was not eliminated in time during the heat treatment process, resulting in deformation or cracking of the valve spool. However, there are more and more complaints later. Blade realized that the service life of the hydraulic cartridge directional control valves from the original cartridge valve manufacturer may be about 1 year. He had to find a new hydraulic cartridge directional control valve manufacturer with a service life of 2 years. A week has passed, and no one can guarantee a 2-year life span.

Blade found AAK when browsing Google. He noticed that AAK was continuously supplying HydraForce, and left a message: Can AAK ensure that each hydraulic cartridge directional control valve spool is free of deformation or cracking within 2 years? I guess he encountered trouble in purchasing hydraulic cartridge directional control valves. After communication, I learned the above information. I replied that the life expectancy of 2 years should not be a big problem. Blade sent the drawing of the hydraulic cartridge directional control valve and asked for the lead time for 10 samples. After 45 days, AAK sent the samples of the hydraulic cartridge directional control valves, but there was no email from him after that.

Last week, Blade suddenly sent an email, and it was a PO for 600 hydraulic cartridge directional control valves. It can be seen that the samples of AAK hydraulic cartridge directional control valve was approved by his customer. The valve spool is the key to long service life of this hydraulic cartridge directional control valve.

1. AAK select 20CrMo material to produce the valve spool. After quenching and tempering, the materials are more conducive to processing. Most hydraulic cartridge valve manufacturers ignore this action.

2. 0.25~0.35mm machining allowance shall be reserved for rough turning, then carburizing, quenching and high temperature tempering shall be carried out, and then the valve spool shall be subject to low temperature cold treatment. The surface hardness of such valve spool is above HRC63, and the residual austenite in the internal structure is eliminated.