AAK uses Rockwell hardness tester to check the hardness of each part of the hydraulic valve, so that the hardness of each heat-treated alloy steel is "exposed". Nearly 90% of domestic hydraulic valve manufacturers are not equipped with this Rockwell hardness tester with the highest accuracy. An Italian hydraulic valve customer, who disliked the expensive price of AAK, purchased the high hardness hydraulic directional valves from another hydraulic valve manufacturer but suffered loss from poor quality, he finally returned to AAK to place an order.
Because of the common problem of unstable heat treatment in the industry, the hardness test of hydraulic valves with high requirements for stability is very important. Most hydraulic valve manufacturers can't grasp the details of hardness testing. They don't have high-precision hardness testing instruments, just checking the hardness by experience. They often put on-line production without knowing the hardness of materials is not up to standard due to human errors.
Harvey is a hydraulic valve purchaser from Italy. In particular, there are many inquiries for hydraulic directional valves, and the hardness requirements for hydraulic directional valves are particularly high, with few requirements below 65HRC. Since last year, he has sent AAK inquiries for hydraulic directional valves every 2 weeks, all of which are 65-68HRC hardness indicators. Strangely, there were 10 inquiries for hydraulic directional valve, but no order was placed with AAK. Every time we followed, the reply we almost received was "the price is too high and will not be considered for the time being". We realized that this is not our customer.
In June this year, Harvey sent an inquiry for the hydraulic directional valve with 68HRC hardness index, which is very similar to the 68HRC hydraulic directional valve inquired last year. We didn't quote the same day and intended to give up. The next day, he emailed again to ask whether his inquiry had been received. We replied that the AAK price doesn't meet your goal. We won't make an offer for the time being. Let's make friends. Harvey probably realized that AAK didn't want to waste time, he told us the truth frankly. There was a problem with the 68HRC hardness hydraulic directional valve he purchased from another hydraulic valve manufacturer. Strangely, the thickness measured in the shipping inspection link was up to standard. After the customer received the shipments of hydraulic directional valve, there were continuous complaints, all of which were due to the instability of the hydraulic system caused by unqualified hardness.
From his description, I felt that there was something wrong with the testing instrument and asked him to send samples to us for testing. He was surprised when he learned from the other hydraulic valve manufacturer that there was no test report for 68HRC hardness. Before placing the order, Harvey's colleague visited the hydraulic valve manufacturer, who has its own heat treatment processing plant, and the heat treatment testing link is also equipped with a Leeb hardness tester to check the hardness. The price of their hydraulic directional valve was 6% cheaper than AAK HYDRAULIC VALVE, so order was placed with this hydraulic valve manufacturer.
Harvey was curious about how we detected that these hydraulic directional valves did not have a hardness of 68HRC. AAK has been engaged in the hydraulic valve industry for so many years, wholeheartedly pursuing product quality and checking step by step from material selection. In terms of hardness index, it not only has its own exclusive heat treatment plant, but also has its own exclusive quenching and tempering heat treatment process. Through the combination of quenching and tempering at different temperatures, the hardness of materials can be greatly improved. At the same time, the testing equipment is equipped with Rockwell hardness tester with the highest accuracy in China. The hardness testing range is HRC 20 ~ 70. As long as the hardness requirement is within this range, the test error will not exceed +/- 0.1HRC, while the detection range of Leeb hardness tester used by most hydraulic valve manufacturers is HRC 20.4-67.1. If the hardness exceeds this range, the test data is distorted. In high precision, we benchmarked Eaton Vickers directional hydraulic valve.
Harvey suddenly understood and hoped that we could maintain the original quotation for this inquiry for the hydraulic directional valve, and asked us to arrange samples of the hydraulic directional valve within 10 days and send them to his customers for testing. 3 days later, Harvey sent the order for the hydraulic directional valve. He said that he recognized the product hardness of AAK hydraulic valve very much, and would send the inquiry of 68HRC hydraulic directional valve to AAK only in the future.
AAK HYDRAULIC VALVE has a rigid heart never compromising on quality and high-precision equipment. You can buy at ease, use at ease, worthy of a try.
AAK HYDRAULIC VALVE (110) 2021-12-03