Bill is a purchaser of Manitowoc company in the United States. Two years ago, AAK received an inquiry about hydraulic counterbalance valves from him, and there were few contacts later. Unexpectedly, two years later, we received an email from him consulting about the problems of the hydraulic counterbalance valves. After communication, we learned that a batch of hydraulic counterbalance valves he purchased elsewhere had problems and almost got into a big trouble. Last summer, a crane shipped by their company, the crane winch system lost control during construction and the hook slipped off. Fortunately, there was no one under the hook at that time, otherwise there would be great trouble. According to the analysis of the field engineer, it is considered that the hydraulic counterbalance valve used in the crane winch system is abnormal. After disassembling the hydraulic counterbalance valve, it is found that there is a deviation in the concentricity between the valve spool and the valve seat. The valve spool is affected by large eccentric hydraulic force, so that the hydraulic counterbalance valve lost its function of balance and the hook slipped off. After knowing the reason, Bill contacted the original hydraulic counterbalance valve supplier. The supplier replied that the hydraulic counterbalance valves were indeed within the warranty period, he can replace the abnormal hydraulic counterbalance valves with a new ones, but can not guarantee that each hydraulic counterbalance valve had the same concentricity and could be used for more than 1 year. Bill was worried about the stability of the new hydraulic counterbalance valves. He didn't want to have big trouble and had to find a new hydraulic counterbalance valve manufacturer. In crane hydraulic system, the performance of hydraulic counterbalance valve is the cornerstone of winch system, and the consistency of hydraulic counterbalance valve concentricity is the key. Bill also asked other hydraulic counterbalance valve manufacturers. No factory guarantees that the concentricity of the hydraulic counterbalance valve can be still consistent after 1 year of use. Bill wants to know how about the concentricity of AAK hydraulic counterbalance valves after being used for 1 year. We told Bill that perhaps having a try is the best answer. He can detect the concentricity of AAK hydraulic counterbalance valves in an all-round way. After 15 days, we sent 4 samples of hydraulic counterbalance valves according to his drawings. Seven days later, Bill informed us that the concentricity test data of AAK hydraulic counterbalance valves were indeed more comprehensive than that of his original manufacturer. How to ensure that the concentricity of AAK hydraulic counterbalance valves is still consistent after 1 year of use? For some manufacturers, when processing the components of hydraulic counterbalance valves, there are discrepancies between the specification parameters and design,
Smith is the head purchasing of a hydraulic company from California. His purchasing of hydraulic valves in recent years has been smooth. In the last hydraulic valve block order, the parameters were normal when the hydraulic valve block approval sample was tested for the first time, but there was oil leakage in the second test on the hydraulic valve block. After rechecking, the oil leaked again in the third test on the hydraulic valve block. Smith communicated with the hydraulic valve block manufacturer for many times but without results. The manufacturer said that this is the traditional sealing process of hydraulic valve block, Smith should either accept it as is or cancel the order. Smith knew that the delivery date confirmed with the customer was due in 1 month, so it was urgent to find a new hydraulic valve block manufacturer to replace the current one. Smith checked the sealing process of no less than 20 hydraulic valve block manufacturers. They all adopted the traditional sealing method of hexagonal plug combined with and sealing gasket. Smith knew that although this sealing method is simple to operate, it has very high requirements for tightening torque. When the torque parameters are not up to standard, the hydraulic valve block is easy to leak. In order to prevent leakage, some hydraulic valve block manufacturers apply anaerobic glue on the threads. During operation, the particles of anaerobic glue fall into the valve hole, causing oil pollution or valve jamming of the hydraulic valve block. The delivery date is approaching day by day, but the new qualified hydraulic valve block manufacturer has not been found yet. Smith is worried and asks around. His friend Caleb gave him the contact information of AAK hydraulic valve. Caleb is also our hydraulic valve customer in the United States. He suggested Smith contact AAK, and told him that AAK hydraulic valve exports to European and American markets all year round and has some unique R & D processes. Perhaps AAK will be different in the sealing treatment process of hydraulic valve block. Smith directly sent us the hydraulic valve block drawing and required that the traditional sealing technology should not be used. A week later, AAK sent the hydraulic valve block sample successfully. Two weeks later, Smith informed AAK by email that the parameters of AAK hydraulic valve block were fully up to standard after 3 tests, and there was still no leakage after the 4th and 5th tests. Smith is very curious about how the sealing process of AAK hydraulic valve block is different from that of other hydraulic valve manufacturers? The vast majority of hydraulic valve manufacturers fail to seal the hydraulic valve block in place because they stick to the rules in technology. 6 years ago, AAK was eliminated by the customer due to the leakage of the traditional sealing technology of the hydraulic valve block. After that, we deci
In the Spring Festival, I received a confirmed price for a large quantity of hydraulic check valves from Stephen. The contact between Stephen and I is only 2-3 times in the whole last year. It was noted at the end of the email that he needs me to contact him as soon as possible to discuss this hydraulic check valve. Stephen comes from American CASE company. We met the year before last. After communication, it was learned that at the beginning of last year, a bulldozer of their company needed to use hydraulic check valve, the one that AAK had made samples at the beginning. Because the price of AAK hydraulic check valve was 20% higher than that of his original supplier, Stephen did not choose to purchase hydraulic check valve from AAK. Some time ago, the customer complained that the hydraulic pump was damaged due to the sudden increase of hydraulic system pressure. Stephen communicated with the original hydraulic check valve manufacturer and the manufacturer replaced the hydraulic check valve with a new one, but 3 months later, the same problem came again. The customer was very dissatisfied that this delayed the construction and needed the problem solved at one time. Stephen went back to AAK and asked about the price of the hydraulic check valve. He needed us to maintain the quotation offered last year. I asked Stephen why he went back to AAK to purchase the hydraulic check valve. He told that since the first complaint from the customer, their engineers retested the original hydraulic check valve samples. The hardness of AAK sample was the highest, and the material hardness of each part of the hydraulic check valve was no less than HRC65. I know why their hydraulic check valve went on strike in 3 months. When we made the sample, we knew that the working pressure was more than 450bar, which was a challenge for the hydraulic check valve. The material hardness of each part of the hydraulic check valve is required to reach more than HRC65. There may be no more than 5 hydraulic valve manufacturers that can reach this level in Ningbo. Stephen wondered why the material hardness of each part of AAK hydraulic check valve can be over HRC65? 1. Material selection is the core. AAK adopts 20CrNi2MoV high carburizing bearing steel imported from Germany for this hydraulic check valve. 2. Heat treatment is the key. Through secondary quenching + cryogenic treatment + low-temperature tempering process, it is cooled to 650 ~ 700 and put into the furnace. After cooling to 450 ~ 500 , it is discharged from the furnace. The micro hardness is 237 ~ 247 HV. 3. In the later stage, point-to-point testing is the key. SonoDur3, a Rockwell hardness tester imported from Germany, adopts the UCI hardness test method, and the test program is fast and mobile to carry out nondestructive testing on the hardness of each component of the hydraulic check valve efficiently and accurately.
When back from the Spring Festival, we received a reorder for 120 hydraulic threaded cartridge valves from Echerle company. Dean has been engaged in hydraulic parts purchasing in Echerle company for many years, and has been doing very well. The boss also trusts him. At the beginning of last year, the company developed a new hydraulic power unit, which has high requirements for the accuracy of the hydraulic threaded cartridge valve to be used. Because of the high accuracy requirement, the original hydraulic threaded cartridge valve manufacturer said that he was not able to achieve it. Dean used a new hydraulic threaded cartridge valve manufacturer finally. After their hydraulic power unit equipment has been sold for just less than 3 months, the customer complained about insufficient power supply. Their engineers believe that the hydraulic threaded cartridge valve was stuck and caused the problem. However, the hydraulic threaded cartridge valve manufacturer believes that it is caused by the uncleanness of hydraulic oil, but the engineer detected that the hydraulic oil is normal. The owner was not satisfied with such a hydraulic threaded cartridge valve manufacturer and asked dean to find a new hydraulic valve manufacturer and replenish goods as soon as possible. Dean left a message on AAK website and asked, what are the reasons for the stuck of the hydraulic threaded cartridge valve? We estimated that he had encountered the complaint about the stuck of hydraulic threaded cartridge valve. After communication, we learned that he was cheated by the new hydraulic valve manufacturer. According to the hydraulic threaded cartridge valve drawings sent by him, the accuracy requirements are high, especially the dimensional accuracy requirement of the valve hole is IT7 ~ 4. Among the hydraulic valve manufacturers in Ningbo, there may be no more than 3 factories that are able to meet it. We suggested Dean send the abnormal hydraulic threaded cartridge valve to us. After receiving and disassembling the sample, it was found that the cylindricity and coaxiality of the valve hole of the hydraulic threaded cartridge valve had errors, that is, the accuracy was not enough, the pressure in the matching gap between the valve hole and the valve spool is not balanced, resulting in the limited flexibility and easy stagnation of the valve spool in the valve body. Dean asked whether we can produce hydraulic threaded cartridge valves meeting valve hole accuracy requirements of IT7 ~ 4? We told Dean that for the hydraulic threaded cartridge valve, the valve hole accuracy is the key point and also the difficulty of quality control process. It directly affects the working performance, service life and stability of the hydraulic threaded cartridge valve. General hydraulic valve manufacturers surrender to this accuracy. AAK has a precision honing machine imported from the United States, which guarantees the finishing of the valve hole of the hydraulic thread cartridg
Malcolm is a purchaser from an American hydraulic equipment manufacturer. He has purchased various hydraulic valves from AAK for some years. We know each other very well. At the beginning of the year before last, their company received an urgent order from a customer in South America. The company required that the accessories of the whole hydraulic system must be in place within 20 days. AAK is their long-term supplier of hydraulic valve blocks. Malcolm estimates that if the hydraulic valve blocks are purchased from AAK this time, including the transportation and customs clearance time, it will be over 20 days. AAK is only required to offer the quotation according to the hydraulic valve block drawings for their file and is informed that due to time constraints, they will first purchase the hydraulic valve blocks from the local hydraulic valve manufacturer this time. About 8 months after our quotation, Malcolm asked by email about what is the reason for the leakage of the hydraulic valve blocks. I asked jokingly if leakage happened in the hydraulic valve blocks purchased locally last time. He said that the customer initially complained that about 30% of the hydraulic valve blocks were leaking. The local manufacturer also replaced the bad hydraulic valve blocks with new ones. However, 3-4 months after installation, the customer reported that there was leakage fault of the hydraulic valve blocks again. Now the customer is not satisfied with the stability of the hydraulic valve blocks and needs the leakage problem of the hydraulic valve blocks solved at one time. The trouble is that the local hydraulic valve manufacturer in the United States does not cooperate to replace the hydraulic valve blocks again. We replied that if we simply look at the leakage cause of the hydraulic valve block, the probability is that the surface roughness of the hydraulic valve block is not up to standard, or the roughness Ra value of the hydraulic valve block is unstable. According to the requirements of these working conditions of your hydraulic equipment, if the Ra value is stable at 0.4um, the problem of hydraulic valve block leakage will not occur. 10 days later, AAK sent 12 samples of hydraulic valve blocks for emergency first. After 20 days, the remaining 30% of the hydraulic valve block was sent from AAK. Now, 12 months have passed, and no complaint from customer. Malcolm mentioned 2 days ago that the customer was ready to place an order again. This time, his owner said that no matter how urgent it was, it was necessary to purchase from AAK, because AAK hydraulic valve block was the most trustworthy, and the owner would communicate with the customer about the delivery date. Why can AAK achieve the surface roughness Ra value of hydraulic valve block to 0.4um? First of all, the Ra value of the hydraulic valve is the cornerstone. The coarser the surface, the easier it is to wear. The intermediate gap gradually increases during use
Andrew is the purchasing director of VIS Hydraulics in Italy and an old friend of AAK. He has cooperated with AAK for more than 4 years. One morning in October, I received an email from Andrew with the subject of "a big trouble". It is the first time that I received such an emotional email from Andrew. After reading, it turned out that the pressure of a hydraulic power system of their company was not enough, and the customer complained. The root of the problem is that the hydraulic threaded cartridge valve and hydraulic valve block does not match each other. The owner asked him to solve the problem within a month. After communication, it was learned that the hydraulic threaded cartridge valve and the hydraulic valve block purchased by Andrew were not produced by the same manufacturer. Now both manufacturers do not admit that it was their own problem. The hydraulic threaded cartridge valve manufacturer said that the pressure of the hydraulic system was slow due to the processing accuracy of the hydraulic valve block, while the hydraulic valve block manufacturer said that the hydraulic threaded cartridge valve had leakage, resulting in insufficient flow. Andrew failed to communicate for several times and thought of AAK. During so many years of cooperation, only AAK hydraulic valve has no complaint. He hopes that AAK can help him find out what the problem is. Andrew sent us the design drawings of the hydraulic threaded cartridge valve and hydraulic valve block. After analysis, AAK engineers found that the probability is that the design of the hydraulic valve block is unreasonable, the flow area of the through hole designed is not enough, and the direction and position of the oil inlet and outlet are not optimal, resulting in insufficient pressure of the whole hydraulic system. Andrew asked the hydraulic valve block manufacturer to design and produce, but the manufacturer needs 2 months to complete it, while the time given by his owner is only 1 month. Andrew asked the fastest time that AAK can finish the hydraulic valve block. Our engineers are worried that there may be deviation if design the hydraulic valve block alone. If combined with the mapping of the valve, we can achieve 100% of the optimal design scheme. We recommended Andrew to send us the hydraulic threaded cartridge valve, too. After receiving it, the scanning analysis was carried out, and the design scheme was obtained 2 days later. After 20 days, the redesigned hydraulic valve block was sent to Andrew. After installation and commissioning, the pressure of the hydraulic system was normal. After the complaint was resolved, the owner was also happy and asked Andrew to purchase both the hydraulic threaded cartridge valve and hydraulic valve block from AAK in the future. Don't purchase them separately any more. AAK engineers use professional automation studio version 7.0 software to automatically generate simulated hydraulic valve block of
Vasiliev is a purchaser from an oil field production company in Russia. Although he has not been in office for a long time, his purchasing is very smooth. Early last year, he purchased a batch of hydraulic relief valves for the hydraulic system of drilling rigs for oil exploration in Alaska. The testing on the hydraulic relief valve sample from the original supplier was smooth, but the drilling machine was unable to start after working for about 3 months. It was judged on site that the hydraulic relief valve in the equipment was leaking. After further disassembling the hydraulic relief valve, it was found that the O-ring in the hydraulic relief valve was worn and broken. Vasiliev contacted the original hydraulic valve manufacturer. The manufacturer replied that the standard nitrile rubber (NBR) O-ring used for this hydraulic relief valve has a service life of at least more than 1 year. He asked Vasiliev to check the temperature of the working environment. When he learned that it was extremely cold at - 50 â??, the manufacturer said that the sealing ring of the hydraulic relief valve can only be replaced once every 3 months, and there is no other alternative sealing ring. Vasiliev was helpless and had to replace the sealing ring of the hydraulic relief valve to maintain the start-up. Two months after the new O-ring was installed, the hydraulic relief valve leaked again. The engineer complained that the hydraulic relief valve purchased by Vasiliev was too unreliable. Vasiliev has to find new suppliers. He contacted with more than 30 hydraulic valve manufacturers, including we AAK hydraulic valve. Nearly all manufacturers replied that under the extremely cold condition of - 50 â??, it is normal for sealing ring to have a service life of only 2-3 months. Only a few hydraulic valve manufacturers are willing to test new materials, but the lead time is to be determined. After receiving the email, AAK just asked about the quantity and delivery date, and told Vasiliev that our product quality can be guaranteed for 1 year under the extremely cold condition of - 50 â??. Vasiliev may have realized the AAK hydraulic valve is some different, and asked about 4 why and 3 how in a short email. We replied that there is no need to make sample for this hydraulic relief valve, because we produced a hydraulic relief valve for a North American customer that was used under similar working conditions the year before last. It has been used for more than 1 year and there was no complaint about the leakage of the hydraulic relief valve. Vasiliev was still rather in doubt about this, but he had no other choice except to try AAK hydraulic relief valve, because other hydraulic valve manufacturers either gave up or can not determine the lead time. After 30 days, AAK delivered the hydraulic relief valve as scheduled. After the test was normal, the original hydraulic relief valve was replaced.
William is a purchaser of a hydraulic equipment company in the United States. At the beginning of last year, a South American customer wanted to customize a drilling machine for geological exploration. The South American customer promised to order this equipment for a long time if it has excellent performance and stability. The owner asked the engineers to design and test samples. According to the working conditions, the maximum pressure of the hydraulic system is 450bar or above, which has a very high requirement on the pressure resistance and stability of the hydraulic pilot operated pressure control valves. When William received the task of purchasing this hydraulic pilot operated pressure control valve, he felt a big pressure, because the pressure resistance of normal hydraulic pilot operated pressure control valve is basically 250bar, and the maximum pressure resistance provided by previous hydraulic valve manufacturers was also only 380bar. He asked all the hydraulic valve manufacturers that he contacted before, they basically replied that according to this working condition, their hydraulic pilot operated pressure control valve can only ensure a service life of 3 months, but the customer asked for a service life of 1 year. William also contacted the local hydraulic valve manufacturers in the United States. They told him that he could not promise a service life of 1 year for this hydraulic pilot operated pressure control valve. They can only test the samples first, then to know the service life. One of his other hydraulic valve manufacturers in China introduced AAK to him. He told William that AAK shipped a hydraulic pilot operated pressure control valve for a working condition of maximum pressure 450bar before, but the service life required by that customer is 6 months. After receiving the drawings of the hydraulic pilot operated pressure control valve from William, AAK technical team found that the requirements of this hydraulic pilot operated pressure control valve were higher than those of our last shipment. The conventional No. 45 steel could not meet the requirements, so we had to find special steel. Later, after 5 times of material selection and testing, 2 months later, AAK internal sample testing was successful by using a German steel with high wear resistance and high fatigue resistance. After sending the samples of hydraulic pilot operated pressure control valve, we have been waiting for news from William. William said that no news from customer is the best news. Last month, 1 year after AAK samples were sent, William emailed us that he would order 100 hydraulic pilot operated pressure control valves at one time. The quality standard is the same as that of the hydraulic pilot operated pressure control valves sent last year. Because the other hydraulic valve manufacturers in China can only ensure the service life of 3 months,
At the beginning of last year, LIEBHERR customized a high-power and high-pressure excavator for their customer. 6 months later, customer complained about oil leakage. After testing, the engineer found that there was no problem with the hydraulic relief valve. The leakage was concentrated in the auxiliary valve, so it was locked as a sealing problem. After disassembling the hydraulic relief valve, it was found that it was caused by the serious wear of the sealing ring. David was responsible for the purchase of hydraulic valves. After he contacted the original factory of hydraulic relief valve, the manufacturer soon sent a new sealing ring. However, a similar situation occurred again in 2 months, and the sealing ring of hydraulic relief valve was replaced for 3 consecutive cycles. The customer was very dissatisfied with this after-sales service and complained directly to the headquarters. The owner asked David to come up with a thorough solution as soon as possible. David was also surprised why the sealing ring of the hydraulic relief valve had to be replaced in 2 months. The manufacturer informed that the pressure and limit temperature of this equipment are very special, especially for high-frequency operation. The service life of the sealing ring of the hydraulic relief valve can only be guaranteed in 2 months, it has to be replaced every 2 months, no other solution. David contacted many other hydraulic valve manufacturers, most of them said that they could only replace the sealing ring every 2 months, and some also suggested changing the whole hydraulic system assembly of the excavator. After 1 year, David hasn't come up with a new plan yet. The customer is unhappy and the owner keeps pushing him. David browsed AAK website and asked directly by email whether AAK has tips on the sealing ring of hydraulic relief valve or not. After receiving the drawings and working conditions of the hydraulic relief valve from David, we found that the pressure of the hydraulic relief valve is 550bar, the limit temperature is 180 â??, and it has very high-frequency operation. Even the high temperature resistant fluororubber sealing ring is not suitable for this hydraulic relief valve. After 3 days of thinking, AAK technical team jumped out of the dead end of thinking about the material of the sealing ring. Can we redesign the structure between the sealing ring and the valve? After the test, it was found that adding "Glyd-ring" may solve the sealing problem of the hydraulic relief valve. David asked us to design and make samples of the hydraulic relief valve installed with Glyd-ring as soon as possible.
Walt placed an order for 1000 hydraulic threaded cartridge valves at one time last week, which surprised me. Three years ago, I met Walt from an American company at the Shanghai PTC exhibition. He communicated with us at our booth for more than half an hour. After the exhibition, Walt sent an email saying that his company happened to have a newly developed hydraulic equipment, which needs to use hydraulic threaded cartridge valves. He asked AAK to urgently provide 30 samples of hydraulic threaded cartridge valves according to his drawings. AAK sent out 30 hydraulic threaded cartridge valves after 25 days. After this, there was no inquiry for any hydraulic threaded cartridge valves from him. Half a year later, Walt sent a new test order of 40pcs for another new hydraulic threaded cartridge valve. Same as last time, there is no further news after delivery. In this way, we just received 2 test orders in about 2 years. I thought that there should be a mistake on the quantity of this large order of hydraulic threaded cartridge valve this time. After several rounds of emails, we know the story for this hydraulic threaded cartridge valve. Their company has only begun to purchase hydraulic valves from China in recent 3 years. For the hydraulic threaded cartridge valves purchased at the beginning, there are always complaints from customers after a period of time, such as leakage or jamming, insensitive opening and closing or serious wear and tear, etc. In the past 2 years, Walt also tried samples from more than 20 hydraulic valve manufacturers. The same problems still occur after each replacement. Only AAK hydraulic threaded cartridge valves have not received a complaint. Walt compared more than 20 suppliers for 2 years, and only AAK hydraulic threaded cartridge valves had no complaints. This time, he strongly suggested his owner that the future hydraulic threaded cartridge valves can only be purchased from AAK. His owner also wants to know why AAK can ensure that there are no complaints about the hydraulic threaded cartridge valves. AAK hydraulic valve not only has the CNC machining center imported from Switzerland, but also has its own upgraded and refitted independent fixtures, which eliminates man-made errors. At the same time, we have accurately controlled every detail of the processing, production, assembly, inspection and packaging of each hydraulic threaded cartridge valve, which has surpassed the vast majority of domestic peers. Firstly, AAK will divide the installed products into several assembly units according to the structure and process characteristics of the hydraulic valve, reduce the single parts entering the general assembly as much as possible, and ensure the reasonable assembly sequence and specified assembly accuracy of the hydraulic valve. All parts will be accurately measured, strictly inspected and tested before and after the general assembly of the hydraulic threaded cartridge valve.
Last week, Eddy emailed me that after AAK hydraulic check valves of the test order has been used for 3 months , the O-ring seal was still free of wear. He was finally relieved. Eddy, who works at Terex company in the United States, has successfully purchased hydraulic valves from China over the years, and his owner is also very satisfied. At the beginning of last year, a customer complained about the hydraulic equipment supplied by their company for offshore oil field exploitation, which made him very passive. Some equipment has the phenomenon that the drilling machine rises slowly or cannot rise. Their engineer found that the hydraulic check valves used in the oil circuit of the hydraulic equipment had internal leakage, the one-way oil circuit could not be fully locked, resulting in the inability of the equipment to rise. Their engineer can only replace the hydraulic check valves with the previous spare ones and bring the problematic hydraulic check valves back to the company. Eddy sent these hydraulic check valves to the original supplier. The supplier replied that the reason for the leakage in the hydraulic check valves was that the ambient temperature was too low. The O-ring seal of the hydraulic check valves was hardened and worn quickly in extremely cold conditions, which was difficult to solve. Eddy knows that if he can't give reply to customer like this, he must find a manufacturer who is able to produce the hydraulic check valves working at low temperature. Eddy contacted several hydraulic check valve manufacturers, most of them reported that it was difficult to achieve 100% leakage free under such extremely cold conditions. Eddy was worried. When Eddy contacted us, our engineer wanted to see the real reason for the wear of the O-ring of his hydraulic check valves and asked him to send the defective hydraulic check valves. After receiving the samples, our engineer realized that even if the cold resistant O-ring is used, it may not be 100% leak free, and the structure of the sealing ring needs to be changed, because the internal structure of this hydraulic check valve is a little complex. Eddy said that this is the only different reply he received. It seems that Eddy still doesn't believe that AAK can solve the leakage problem of the hydraulic check valves. I told him that a Russian customer has purchased hydraulic relief valves from us, and their hydraulic equipment is also used in oil fields. The customer told us that under extremely cold conditions, the service life of AAK hydraulic relief valve is more than 4 times that of its peers. Three weeks later, we sent 4 pieces of hydraulic check valves of the test order to Eddy. There was no news after 3 months. Until last week, we received email from Eddy amazing that their engineers also admired our idea of adding retaining ring to the O-ring of the hydraulic check valves.
The email from Draper this morning made me in a good mood all day. I had two bowls of rice at noon. He said that 5 months have passed since AAK supplied the hydraulic needle valves in September last year, they have not received any complaints from users. His owner finally accepted his suggestion: "AAK is the preferred supplier for hydraulic needle valves, even if the price is 20% more expensive". Draper, whom we met in 2019, is a purchasing veteran of Doedijns company in the Netherlands. In 2019, he purchased 3 small batches of hydraulic needle valves from AAK in 3 times. He was very satisfied with the quality and service of AAK hydraulic valves, but in the recent two years of 2020 and 2021, he basically just placed orders for the very difficult and small quantity of hydraulic valves. Draper told the truth privately that he couldn't persuade the owner to place a big order with AAK. The problem is the price. Sometimes the price of AAK hydraulic valves is 20% higher than that of other manufacturers. Only the orders that are out of the capacity other hydraulic valve manufacturers will be placed with AAK. Last July, Draper sent us an email with the subject of "the production time of 1200 hydraulic needle valves". Because he had never sent an inquiry for such a big quantity of hydraulic needle valves, I thought that he sent the email to us by mistake. After communication, it was learned that he finally persuaded the owner to place big order with AAK even if the hydraulic needle valve is 20% more expensive, because they don't want to waste time on the after-sales for the hydraulic needle valves. In the past 2 years, customers have complained more and more about the hydraulic needle valves purchased by Draper. The complaints are basically about some small details of the hydraulic needle valves. For example, the hidden burr of the hydraulic needle valves in the hydraulic power system is not completely cleaned, which affects the matching accuracy and assembly of various parts in the system, as well as the tightness of the matching interface, resulting in internal leakage. Some hydraulic needle valves are complained by users after being used for even only 3 months. For many times, they needed to replace the hydraulic needle valves for users with new ones, which wasted too much of time due to after-sales and also interrupted the construction progress of users. The 1200 hydraulic needle valves purchased from AAK this time are the repeat order for their old customer. The customer said that they will not accept the repair of hydraulic power equipment within 6 months for any reason. Draper once again suggested the owner purchase the hydraulic needle valves from AAK, because in the past 3 years, there has never been any abnormal quality of any hydraulic valves purchased from AAK within 12 months.
Taylor suddenly emailed us to ask if we can deliver 110 hydraulic diverter valves within 20 days? As the purchasing manager of Caterpillar, Taylor has cooperated with AAK for several years, but since the last half year, there has been only inquiry and no actual order. There must be a reason for this urgent hydraulic diverter valve order. Taylor said that the customer complained that their excavator was weak. The hydraulic diverter valves used in the excavator were abnormal. Their engineers found that the valve spool of the hydraulic diverter valve was stuck, so they had to re purchase new hydraulic diverter valves for replacement. The customer asked them to replace these hydraulic diverter valves within 1 month. This time was very tight, and Taylor didn't have any confidence about it at all. The original manufacturer considered that the residues in the valve were due to the unclean hydraulic oil used, and was unwilling to offer free replacement for the hydraulic diverter valves. He only can accept to produce the hydraulic diverter valves for another new order, but it would take 35 days to complete it. After disassembling the hydraulic diverter valve, the Caterpillar engineer found that there were a few fine metal particles left on the contact surface between the valve spool and the valve sleeve, and no particles were found in the hydraulic oil. These particles were caused by incomplete cleaning of the hydraulic diverter valve after processing, but the original manufacturer still denied it. Taylor had to contact other hydraulic diverter valve manufacturers, including several local factories in the United States. Unfortunately, none of them were able to complete the production of 110 hydraulic diverter valves in 20 days. This is why Taylor emailed to AAK. He regretted to save 20% of the price, resulted in the current embarrassing situation. We don't know whether we can complete the production of 110 hydraulic diverter valves within 20 days. One day later, we advised Taylor that we are 90% confident that we can complete the production of this batch of hydraulic diverter valves. This hydraulic diverter valve is just very close to another one that we produced for a German company. We still have the stock materials, but only need to adjust the size slightly. This can save some time. After 20 days, the 110 excavator hydraulic diverter valves were successfully delivered, and their company successfully replaced the hydraulic diverter valves. The customer was very satisfied with their after-sales speed, and Taylor was finally relieved. AAK hydraulic diverter valve strictly controls and tests each production process, especially the cleaning in the valve is clean. We use the ultrasonic cleaning machine imported from Japan, which converts the sound energy of the power ultrasonic frequency source into mechanical vibration through the transducer, and rad
The angle error of inner cone of AAK hydraulic relief valve sleeve is controlled within ± 0.8 , and the minimum axial grinding tolerance of sealing circle is 0.07m. At the same time, it is inspected by three coordinate measuring instrument to ensure that the hydraulic relief valve is 100% leak free. After comparing more than 10 hydraulic valve manufacturers, Backhaus determined that AAK hydraulic valve is the most reliable hydraulic relief valve manufacturer. At present, in the manufacturing process of hydraulic relief valve, when grinding the conical surface inside the valve, most hydraulic valve manufacturers just let the operator judges the feed rate, angle control and grinding tolerance by experience completely. There is no grinding amount detection link, and there is no precision detection of each part in the valve. When this type of common quality hydraulic relief valve is used on equipment with high requirements, troubles will come out. Backhaus is a purchaser of a German hydraulic pump company for less than a year. In the first half of the year, a batch of hydraulic pumps of their company were complained by customers. After the hydraulic pump is started, the system pressure begins to lose stability and there is pressure drift. The engineer judged that there was a problem with the hydraulic relief valve. After disassembly, it was found that there was a gap between the valve sleeve and valve spool of the hydraulic relief valve. After measurement, it was found that the error of the cone angle in the valve sleeve of the hydraulic relief valve was too big and caused leakage of the hydraulic relief valve. The only solution is to replace the hydraulic relief valve. It is estimated that 30% of hydraulic relief valves need to be replaced. The owner asked Backhaus to replenish the goods as soon as possible and solve the customer complaints. Backhaus contacted the original manufacturer of the hydraulic relief valve. The manufacturer was willing to replenish. Backhaus thought it would be all right after replacing the hydraulic relief valve. A month later, the customer complained again, which is still the same problem. This shows that the quality of the hydraulic relief valve from the old manufacturer is not trustworthy, and it is urgent to replace the hydraulic relief valve supplier. Backhaus contacted more than 10 hydraulic relief valve manufacturers, including AAK hydraulic valve. The hydraulic relief valve is required to be 100% leak free. AAK hydraulic valve and other 3 manufacturers are required to send samples for testing according to his hydraulic relief valve drawings and working conditions. A month later, Backhaus asked us about the production time of replenishing 30% hydraulic relief valve. It should be that AAK hydraulic relief valve has been recognized by the customer.
AAK hydraulic valve blocks adopt MB Series Plug of KVT company in Switzerland, and forms a solid sealing surface after metal extrusion in the way of expansion bite, 100% avoiding oil seepage and oil leakage of hydraulic valve block, which fundamentally solves the problem of high-pressure plugging of hydraulic valve block, and the rated pressure can be as high as 450bar without pollution. Most hydraulic valve manufacturers fail to seal the hydraulic valve block in place, but AAK has become a long-term cooperative supplier of hydraulic valve block for American customer. The vast majority of hydraulic valve manufacturers use the traditional sealing method of inner hexagonal (or outer hexagonal) screw plug and sealing combination gasket to process the hydraulic valve block. The service pressure is basically in the range of 50-300bar, and the operation is simple and easy to disassemble. The hidden danger is that there are requirements for tightening torque. If the torque is not reached, it is easy to leak, and if it exceeds, the thread is easy to be damaged, some hydraulic valve manufacturers even apply anaerobic glue on the thread, which is easy to cause particles of anaerobic glue to fall into the hole, resulting in oil pollution or valve jamming of the hydraulic valve. In addition to the function of hydraulic logic control, some hydraulic valve blocks also need to work for a long time in the environment of high-pressure, high-frequency pressure impact and temperature impact. Therefore, the sealing process of hydraulic valve blocks is very important. Declan, an American customer, is a hydraulic friend of Blake. He recently encountered trouble in purchasing the hydraulic valve block. The approval sample of the hydraulic valve block provided by the original factory showed that the parameters were completely normal in the first test, and there was slight oil seepage in the second test. Declan thought it was something wrong with the hydraulic system. Declan checked and tested the samples for the third time, the hydraulic valve block began to leak oil. After communicated with the original manufacturer, Declan was advised that this sealing process is common in the industry, he should either accept the hydraulic valve block as is or cancel the order. Declan consulted more than 30 hydraulic valve manufacturers through B2B, Google and other websites. Their hydraulic valve blocks all adopt the general sealing process in the industry, and can not guarantee 100% sealing. After consulting Blake, Blake suggested him contacting AAK and told him that AAK hydraulic valves are not market goods and have some their own R & D processes. Perhaps AAK does not adopt the general sealing process in the industry for the sealing of hydraulic valve blocks. According to the hydraulic valve block drawings from Declan, we sent out the hydraulic valve block samples a week later.
Richard is a purchaser of ATOS company in Italy. Last September, ATOS received a complaint from a South African customer that the starting pressure of the hydraulic pump was often insufficient recently. The field engineer analyzed that the valve spool spring of the pilot hydraulic relief valve of the hydraulic pump was deformed, resulting in the unstable pressure of the hydraulic system. He tried to replace the pilot hydraulic relief valve to solve the problem. The customer questioned the stability of their equipment because it had been used for less than 1 year. After learning about it, the owner asked Richard to solve the customer complaint as soon as possible and replace this batch of pilot hydraulic relief valves. Richard wondered about the problem with the pilot hydraulic relief valve. This pilot hydraulic relief valve was produced by an American company and was re purchased this time. The original manufacturer replied that this pilot hydraulic relief valve has been produced according to the standard. The strength limit and elastic limit of the piano steel wire used meet the requirements. The problem should be caused by improper use by the user. Of course, he can not tell the owner of such results. The original manufacturer was unwilling to take responsibility. Richard contacted nearly 20 hydraulic valve manufacturers, including AAK hydraulic valve. After several rounds of communication, Richard eliminated half of the hydraulic valve manufacturers, and then asked the shortlisted hydraulic valve manufacturers to send their own ready-made pilot hydraulic relief valves. Their company conducted spring elasticity test. Finally, 5 manufacturers were selected to send samples for the second round according to the drawing size of his pilot hydraulic relief valve and improve the spring elasticity. After communicating with Richard, we learned that the service limit pressure of the hydraulic pump is above 350bar and the service frequency is very high. Although the piano wire spring used by Sun, the original American manufacturer, is advanced, special materials must be used for this special working condition. We started to test the special spring first. Richard has received samples of pilot hydraulic relief valves from other 4 factories, but AAK hasn't sent them yet. Richard pushed us several times and we advised that we are still in testing. Richard may think AAK should not be able to do it. AAK engineers spent 3 weeks, 6 times replacing materials and 9 times proofing, determined the special alloy steel spring as a trial, and sent the pilot hydraulic relief valve 30 days later. We specially asked Richard about the test of the pilot hydraulic relief valves from the other 4 manufacturers. Richard advised that if AAK pilot hydraulic relief valve could not pass the test, he would need a new round of looking for suppliers.
Bauer is a purchaser of American PowerTeam company. In recent years, the purchasing of hydraulic valves has been smooth. Last October, PowerTeam received a test order for a hydraulic power unit from a South African customer. The customer requires to receive the prototype in the shortest time. If the prototype test is normal, there will be a series of orders later. The boss attached great importance to it and asked the technical team to design and develop it. What the engineers are most worried about is that the use frequency of the hydraulic power unit is twice that of the conventional one. Therefore, the durability of the hydraulic threaded cartridge valve used should be at least more than 2 million times. According to the parameters and working conditions of the hydraulic threaded cartridge valve, Bauer contacted more than 20 new and old hydraulic valve manufacturers. After one-to-one communication, he selected 5 hydraulic valve manufacturers to make samples for testing. 20 days later, Bauer received 6 samples of hydraulic threaded cartridge valves. After the engineers installed and tested, none of the hydraulic threaded cartridge valves could pass the durability test for 2 million times. Bauer had a second round of communication with the manufacturers, 3 of the hydraulic valve manufacturers said they would re-sample the hydraulic threaded cartridge valve. After the second round of testing, although the durability of hydraulic threaded cartridge valves has been improved, they have not reached 2 million times. Bauer was embarrassed. He might have killed the big order. After communicating, the manufacturer advised that there was nothing he could do. Bauer was very worried and had to try his luck with a new hydraulic valve manufacturer. He found AAK hydraulic valve on Google and searched AAK. After browsing, Bauer thought that AAK might be able to successfully sample this hydraulic threaded cartridge valve. After receiving the working condition requirements and drawings of the hydraulic threaded cartridge valve from Bauer, AAK engineer made analysis and determined that they were more than 95% confident to make it successfully. After 2 rounds of testing, the engineer defined the production process of proofing and circled the technical difficulties. After 20 days, AAK sent the samples of the hydraulic threaded cartridge valve. Unexpectedly, 2 months after the samples of hydraulic threaded cartridge valves were sent, we received the official order of 600 hydraulic threaded cartridge valves from Bauer. Bauer said that the equipment commissioning of South African customer was successful and the operation was stable, they were very satisfied with the quality of PowerTeam. The owner was very satisfied that Bauer found such a great hydraulic valve manufacturer and designated AAK as their exclusive supplier of hydraulic threaded cartridge valves.
The opening and closing characteristics can reach 95% opening rate and 90% closing rate, the operating pressure swing is not greater than ± 0.1MPa, and the design service life is more than 1 million times. For this high precision, high stability and high durability 3-high hydraulic threaded cartridge valve, Jacob is surprised that the AAK hydraulic valve is successful in one-time sample, while most hydraulic valve manufacturers are not able to do at all. Jacob is a purchaser of Intermot company in Italy. The company has a newly developed hydraulic motor, which needs to use hydraulic threaded cartridge valve. This motor is a high-frequency operation and has strict requirements for various parameters, especially for the parameters of hydraulic threaded cartridge valve, which has 3 high requirements of high accuracy, high stability and high durability. The owner asked Jacob to complete the procurement of this batch of hydraulic threaded cartridge valves within 60 days. He selected 4 from the original hydraulic valve suppliers to make samples. After installation, it was found that the opening and closing characteristics of hydraulic threaded cartridge valves can only reach 90% opening rate and 85% closing rate, which is 5% lower than the parameter requirements. Even the operating pressure swing of some hydraulic threaded cartridge valves exceeds 0.2MPa. In the last step testing, only 2 or 3 samples can be intact after 1 million durability tests. If all three requirements should be reached at the same time, nearly none of the samples meet the standard. Due to the limitation of equipment, the original manufacturer said it was difficult to improve significantly. Jacob learned about AAK hydraulic valve under the introduction of its peers. After browsing AAK website (www.aakindustry. com), he felt that the AAK hydraulic threaded cartridge valve might help him. After receiving the parameter requirements and drawings of his hydraulic threaded cartridge valve, we found that the requirements of this hydraulic threaded cartridge valve are not simple, but our technical team needs to chew this hard bone and gave reply to Jacob that if it goes well, the samples of the hydraulic threaded cartridge valve can be sent within 20 days. On the contrary, it needs more time for proofing. Jacob hopes that AAK hydraulic threaded cartridge valve sample will be successful, which just meets the delivery time required by the owner. After 15 days, AAK sent the hydraulic threaded cartridge valve samples successfully. After installation and test by the engineer, all parameters of the hydraulic threaded cartridge valves are qualified and meet the 3 high requirements of high accuracy, high stability and high durability. After 25 days, the shipment of the hydraulic threaded cartridge valve was delivered as scheduled.
Brooke is the purchasing manager of the American company Vickers and has been working with AAK for more than 6 years. One morning last month, he emailed us that his job was finally saved. I was surprised how a veteran suddenly said that he had finally "saved his job". In private, I learned that it was because he had some disagreements with his owner and quarreled. The owner almost let him go. Because his owner is not satisfied with the price of AAK, sometimes the price of AAK for the same hydraulic valve will be more than 20% higher than that of other Chinese hydraulic valve manufacturers. At the cost meeting last month, the owner proposed to replace the Chinese hydraulic valve manufacturer, but Brooke insisted that AAK is the most cost-effective Chinese hydraulic valve manufacturer, so it is not recommended to replace it. On the contrary, he can only leave. The year before last, the owner went to Shanghai PTC exhibition with him to develop suitable Chinese hydraulic valve manufacturers for cooperation. They did get acquainted with many Chinese hydraulic valve manufacturers at the exhibition, but after more than 2 years of testing samples and running in, Brooke found that there is really no second Chinese hydraulic valve manufacturer that can compare with AAK in all aspects. AAK is not only reliable, but also has temperature, whether it is cooperation, delivery, quality, after-sales etc. Brooke remembers the support and help from AAK hydraulic valve over the years. On one occasion, due to the urgent delivery time of a South African customer, Brooke could not find a factory with stock at that time and could only customize it. Most Chinese hydraulic valve manufacturers said that the lead time from sampling to delivery should be at least 2 months. AAK stopped a production line and asked technicians to work overtime to speed up the production. Samples can be produced in 30 days and shipped in 45 days. It is precisely because of the temperature of AAK that Vickers has the opportunity to cooperate with this big customer in South Africa. Every time, AAK products can be successful at one time during testing. They are the best among all Chinese hydraulic valve manufacturers in terms of accuracy, concentricity, fatigue resistance and durability. Brooke's deepest memory is that one time, the South African customer mentioned that the hydraulic valve used for more than 2 years often stuck during work and asked for replacement. After receiving the news, AAK immediately told Brooke to ask the customer to return the goods. After inspection, it turned out that the hydraulic oil used by the South African customer was not clean and caused the problem. Later, AAK disassembled and cleaned the valve and sent it again, and asked the customer to change the hydraulic oil. Until now, no problem has been mentioned. If this happened to other Chinese hydraulic valve manufacturers, their reply must be that this has passed the warranty period.
Erdmann has been a purchaser of German HAWE company for 5 or 6 years and has been doing very well. Last month, the company had a special hydraulic threaded cartridge valve to purchase. Because it is to be used in the Arctic region, the corrosion resistance of hydraulic threaded cartridge valve needs to be very high. The owner asked him to identify the suppliers and approve the samples within 2 months. Erdmann felt that it could be completed within 20 days. He sent the drawings of hydraulic threaded cartridge valves to the original hydraulic valve manufacturers. Only 2 weeks later, he received samples of hydraulic threaded cartridge valves from one factory. The surface gloss of these samples of hydraulic threaded cartridge valves was quite good. The company tested them on the exploration drilling machine and delivered it quickly to the customer. 3 months later, the customer complained that the hydraulic threaded cartridge valve on the hydraulic pump was seriously corroded, some threads were stuck, the equipment could not be started, and the test run was unsuccessful. The owner thought that Erdmann was careless and ignored the use scene of the Arctic region. The owner again asked him to make new samples and do salt spray test inside the company. Actually, Erdmann emphasized that the hydraulic threaded cartridge valve is to be used in the Arctic region. The original supplier said that their hydraulic threaded cartridge valves have good gloss and corrosion resistance, and can be used in the Arctic region. Erdmann communicated with the original hydraulic threaded cartridge valve supplier again, and the reply was that most hydraulic valve manufacturers just adopt the zinc plating process, and he used the nickel plating process which is the highest level of corrosion resistance. Erdmann realized the difficulty of corrosion resistance in the Arctic regions. Erdmann emailed more than 20 hydraulic valve manufacturers who had been contacted before, emphasizing that the hydraulic threaded cartridge valve must be in the highly corrosive environment in the Arctic region, and the service life shall not be less than 9 months. Only 3 hydraulic valve manufacturers said they could have a try, but there was no response from other manufacturers. Erdmann was a little flustered. Erdmann saw AAK hydraulic valve on Google, who supplied to hydraulic pump company in Russia. He felt that AAK might give him a glimmer of hope. He emailed us to ask if we can produce hydraulic threaded cartridge valves to be used in Arctic regions. We directly replied that the components of the valve should be treated by special electroplating process in order to meet the condition in the Arctic regions. After 20 days, AAK sent samples according to his hydraulic threaded cartridge valve drawings. HAWE company conducted salt spray test on samples from all 4 manufacturers, with the corrosion condition twice that of Arctic regions.
