The original manufacturer cannot handle the Hydraulic Cartridge Directional Valve with valve spool Ra0.2, after AAK taking over, it is worry free

China [CN]

Derya is from Türkiye. Most of the customers in Türkiye who contact AAK are dealers of hydraulic cartridge valves, but Derya operates a hydraulic equipment manufacturing company. At the beginning of this year, they developed an aviation hydraulic power unit that requires high-precision hydraulic cartridge directional control valves, especially the surface finish of the valve spool to be controlled within Ra0.3. Derya customized the hydraulic cartridge directional control valve with a manufacturer in China that had been cooperating for 3 years. 2 months later, the debugging of the aviation hydraulic power unit was not smooth, due to the insensitive opening and closing performance of the hydraulic cartridge directional control valve and equipment operation hysteresis. The engineer found that the surface finish of the hydraulic cartridge directional control valve spool from the original manufacturer exceeded Ra0.5. The original hydraulic cartridge valve manufacturer stated that they can only produce more valve spools and select them one by one. Derya realized that the manufacturing quality of the original hydraulic cartridge valve manufacturer was unstable, so he had to choose a new manufacturer for the hydraulic cartridge directional control valve. However, 2 months had passed since then, Derya was in a hurry.

Derya found AAK on Google and left a message: 

1. How long does it take for AAK to customize the hydraulic cartridge directional control valve?

2. Is it possible for AAK to control the smoothness of the valve spool of each hydraulic cartridge directional control valve within Ra0.3?

After communication, it was learned that he was facing the dilemma of customizing a hydraulic cartridge directional control valve. I provided him a customer case of a hydraulic cartridge directional control valve previously customized for a Russian customer, with a surface finish of Ra0.2 on the valve spool and a video of how we handled the surface finish of the valve spool. Derya had no concerns anymore and requested AAK to make samples. After 50 days, AAK sent 20 samples of hydraulic cartridge directional control valves.

4 weeks later, Derya informed us via email that their aviation hydraulic power unit had been successfully tested and was on its way to deliver to the customer. The smoothness of the AAK hydraulic cartridge directional control valve spool was controlled at Ra0.2 and satisfied their engineers.

For AAK hydraulic cartridge directional control valve spool components, the first is to choose suitable materials. For this model, we use 20CrNi2MoV high permeability carbon bearing steel, which has wear-resistant performance and can better protect the smoothness of the valve spool. Then it is polished and precision processed, and AAK uses a Taiwan centerless grinder. The process setting for centerless grinding is done by AAK this way: Firstly, the surface error and feed speed of the grinding wheel are set, and the surface error value of the hydraulic cartridge directional control valve spool is set to within 2μm, the feed speed of the grinding wheel is set at 400mm/min. The relative vibration between the grinding wheel and the valve spool, as well as the contact stiffness between the valve spool, guide wheel components, and support plate, can be more smoothly controlled, ensuring that the surface finish of each hydraulic cartridge directional control valve spool can be controlled within Ra0.2 after processing.

AAK hydraulic cartridge directional control valve, the spool smoothness controlled within Ra0.2, you can also give it a try!

AAK HYDRAULIC VALVES (635) 2024-07-25

https://www.aakindustry.com/info-detail/cartridge-directional-valves-aak635