AAK hydraulic valve used Rockwell hardness tester, Harvey admired

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.

https://www.aakindustry.com/info-detail/hy , draulic-directional-valve-aak110

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