The Accuracy index of Ra value of the surface of hydraulic valve spool

Product Details

Factory Can Not Even Achieve The Valve Spool Ra Value at 0.16μm, but AAK Has Already Mass Produced Hydraulic Valves 5 Times Finer Than It

Charles is our old hydraulic valve customer. Some time ago, he purchased a batch of hydraulic flow valves from a hydraulic valve manufacturer in Guangdong. However, he didn't expect to be busy on changing suppliers before the order was shipped. The hydraulic flow valves can not pass inspection. The surface roughness Ra value of hydraulic valve spool work piece should be below 0.16μm, but there was 0.2μm、0.25μm、0.28μm in mass production. The problem had not been properly solved through repeated communication. Seeing that the delivery date was coming, Charles was worried and could only plan to cancel the order with his customer.

It is easy to lose the customer if there is no solution but directly express the problem like this. His boss asked him to get the solution and let the customer decide whether to cancel the order. I noticed that he was asking for help on LinkedIn. After communicating with him, I learned the whole story.

This hydraulic valve factory in Guangdong is Charles’ old supplier. It has been supplying his company with some conventional hydraulic valves. He had asked the factory whether the surface roughness Ra value of the valve spool could reach below 0.16μm, and the factory said that there was no problem. The proofing was also smooth, then Charles decided to place order with this hydraulic valve factory. Later, it was learned that this hydraulic valve factory could not produce hydraulic valve with Ra value below 0.16μm due to the limitation of its own process equipment and technology. The factory was worried that the customer might walk away, so he accepted the order regardless of his ability. The proofing of this factory’s hydraulic valve was outsourced. It was originally agreed that the mass production was also completed by the proofing factory, but the proofing factory rejected the production of the goods finally. Then the hydraulic valve factory arranged mass production in its own factory without authorization, thinking it could muddle through.

I asked him to send us the drawings of this hydraulic flow valve and told him that AAK had mass produced the valve spool with the Ra value reached 0.02 ~ 0.04μm. He immediately asked the production time of 1000 hydraulic flow valves by e-mail, and asked the old supplier to send us several production samples to see the quality.

After getting the support of AAK, Charles truthfully told his customer that the current goods can not pass inspection, he needs to change factory and needs another two months to for re-production. Unexpectedly, the customer expressed understanding. Out of the trust of cooperation, the customer not only did not cancel the order, but also accepted the new delivery date.

We have produced the hydraulic valves with Ra value of valve spool at 0.02 ~ 0.04μm, which can't be done by our peers. Let's take a look at how AAK hydraulic valve makes the valve spool.

AAK proprietary valve spool processing technology: the valve spool generally uses bar material as blank and is processed after normalizing. The process includes: cutting the end face, drilling the center hole, rough turning and fine turning the outer circle, end face and inner hole of countersunk groove, drilling, milling, heat treatment, grinding the center hole, grinding the outer circle, and finishing the outer circle. At the same time, in grinding, high finish grinding is generally used to make the surface roughness Ra value of the workpiece below 0.16μm, some RA values can even reach 0.02 ~ 0.04μm, the roughness value can be nearly 10 times higher than that of peers.

After we started producing this hydraulic flow valve, and sent a video to show Charles our production situation and progress, he was finally able to relax and said he would start his vacation.

AAK value spool precision, let you rest assured.

AAK Hydraulic Valve (74) 2021-09-01