AAK hydraulic directional control valve, which has been used for 2 years, is free of rust and corrosion. It stands out from 3 hydraulic valve manufacturers. Joseph finally received a large order for 1000 hydraulic directional control valves from customer. Joseph is the purchasing manager of a hydraulic pump company in Italy. Two years ago, the company received a test order for a special chemical hydraulic pump, which needs a hydraulic direction control valve. The customer requires that after 2 years, if the hydraulic directional control valve is free of rust and corrosion, it will have the opportunity to obtain a large order. The boss asked Joseph to find a very professional hydraulic valve manufacturer. Joseph knew that relying only on the existing hydraulic valve suppliers is not enough to guarantee the quality. He checked with all the hydraulic valve manufacturers he had contacted before and the new ones searched online, and selected 16 hydraulic valve factories, including AAK Hydraulic Valve. He asked all hydraulic valve manufacturers to provide 2 samples of hydraulic directional control valves according to the drawing requirements of the customer for testing at their headquarters. According to the post analysis to the drawing of hydraulic directional control valve from Joseph, we found that there is no problem to meet the accuracy, sensitivity and durability of this hydraulic directional control valve, except that the finish of the outer surface of the hydraulic directional control valve must be free of abnormality, rust and corrosion after 2 years of use, which is too uncertain. We didn't receive email from Joseph until 15 days after we sent out the hydraulic directional control valve samples. According to their simulation test, only the hydraulic directional control valves from 3 factories can be approved to send samples to their customer. It would take 2 years for AAK to know if we can get the order of hydraulic directional control valve. At that time, we were very surprised that there were such strange customers. We almost forgot the test order of this hydraulic directional control valve 2 years ago. Last week, Joseph sent an email asking about the production time and new price of 1000 hydraulic directional control valves, and told us that the surface of the hydraulic directional control valves from other two hydraulic valve manufacturers began to have scratches, corrosion, fading and rust after more than a year of use, only the surface gloss of AAK hydraulic direction control valve does not change. In fact, when we sent out the hydraulic directional control valve samples, we were not 100% sure to meet this special requirement, because we used a new process to proofing. We know that the conventional nickel plating, chromium plating, zinc plating, blackening and other processes basically can not keep the same appearance after 2 years of use. We adopted electroless nickel plating.
Donald, a hydraulic valve customer from the United States, recently had an order for hydraulic valve sleeve parts with an old supplier. It took more than 30 days to adjust the approval sample of hydraulic valve sleeve for many times. The taper of hydraulic valve sleeve always failed to meet the customer requirement of 0.3-0.5m. The manufacturer can only give up the order, but this wastes Donald's time. The trouble is that the customer is still urging the progress of the modification of the hydraulic valve sleeve. Donald consulted more than 30 hydraulic valve manufacturers online, but none of them can guarantee that the taper could reach 0.3-0.5m. Only 2 manufacturers indicated that 1-2m is the limit that they can reach. Donald plans to give up this hydraulic valve sleeve order, but he doesn't know how to talk to the customer. While Donald was worried, his colleague Smith gave him the contact information of AAK HYDRAULIC VALVE. Smith had inquired about the hydraulic valve with AAK before. Smith directly emailed us the inquiry requirements and the drawings of the hydraulic valve sleeve, and CC Donald. He asked us to communicate with Donald directly to see how to solve the taper requirements of the hydraulic valve sleeve. After our technical department had a meeting, they found that it was really a bit tricky. At present, they are not sure to tell the specific accuracy of the taper of the hydraulic valve sleeve. Except for the taper of the hydraulic valve sleeve, the straightness and roundness can fully meet the requirements. We can study the taper of the hydraulic valve sleeve while proofing. However, the specific parameters still need to be determined until the final samples come out. With a try attitude, Donald asked us to start sampling the same day. A week later, we sent out the samples of the hydraulic valve sleeve. A few days later, Donald asked by email if we could try again to improve the taper accuracy of our hydraulic valve sleeve from 0.8-1.2m to 0.3-0.5m to meet the customer requirement. AAK technical department made modification and adjustment for 3 days and 2 nights, and sent the modified sample of hydraulic valve sleeve on the 4th day. Donald soon informed that the parameters of the second hydraulic valve sleeve sample of AAK met the requirements. Donald is curious that more than 30 hydraulic valve manufacturers can't achieve the taper accuracy of hydraulic valve sleeve. How can AAK achieve it by making samples only in two times? As a precision part, the precision of hydraulic valve sleeve is guaranteed by operators and equipment, especially precision grinding is very important. For most hydraulic valve manufacturers, the length of the grinder they used is basically an extended grinder with a hole length of 120%. Although it can repair and maintain the hole straightness, the accuracy of the hydraulic valve sleeve can only be controlled at 1-2m maximum.
is a hydraulic customer from the . Recently, a batch of hydraulic cartridge valves he temporarily purchased were in trouble. Because the parameters from customer were not complete, he used the same model product recommended by the hydraulic valve manufacturer instead. During testing, the flow parameters were not equal. The rated flow of the hydraulic cartridge valve was smaller than the working flow and could not be used normally, which wasted more than 10 days and the delivery time was urgent. He contacted with more than 10 hydraulic valve manufacturers. For hydraulic cartridge valves of the same model, their rated flow setting is either smaller than the working flow or close to the working flow of the system. was very distressed that no hydraulic cartridge valve has a rated flow setting greater than the working flow. found HYDRAULIC VALVE on Google. He felt that HYDRAULIC VALVE was a little different from other hydraulic valve manufacturers. With a try attitude, actively contacted us and sent us the product picture and product model of this hydraulic cartridge valve. He just emphasized that the rated flow must be greater than the working flow and asked us to recommend the hydraulic cartridge valve of the same model, there was no any parameter information. After careful comparison, engineers sent pictures and drawings of a hydraulic cartridge valve of the same model. asked us to send the hydraulic cartridge valve samples as soon as possible. On the 3rd day after receiving the hydraulic cartridge valve sample, emailed to inform that the rated flow of hydraulic cartridge valve can really meet the normal operation of their current hydraulic system. expressed his curiosity that the hydraulic cartridge valve model recommended by is consistent with that recommended by other manufacturers. How can there be such a big difference in the rated flow setting For the selection of flow specifications of hydraulic valves, the settings of each factory are different. If the rated flow of the valve is close to the working flow of the system, this situation is the most economical and cost-effective, and it is also the first choice of nearly 90% of hydraulic valve manufacturers. But there may be a problem, once the working flow in the hydraulic system exceeds the rated flow, it will cause hydraulic clamping and affect the hydraulic power. It will also have an adverse impact on the hydraulic system of the valve. To be safe, when all cartridge valves are produced, will give priority to the maximum flow that may pass through the circuit where the hydraulic valve is located, and the setting of rated flow is greater than the maximum flow of operation, so as to ensure the normal operation of whole system, which is also the reason why most customers prefer .
When I opened the mailbox this morning, I saw a reorder for 500 pilot hydraulic relief valves from Jimmy. He mentioned that the pilot hydraulic relief valve designed by AAK had been used for 2 years and without any complaints. Jimmy is a purchaser of American company Vickers, responsible for the purchasing of hydraulic parts. 2 years ago, his company encountered a complaint from customer for a hydraulic pump. The customer complained that it screamed after being used for a period of time. After dissecting, their engineer found that there was a problem with the hydraulic relief valve in the hydraulic pump. The owner asked Jimmy to solve the problem as soon as possible. Jimmy sent the hydraulic relief valve back to the original supplier, but the supplier replied that the inspection result was good. Maybe the problem happened during installation. Jimmyâ??s engineers tested the samples by themselves and found that there was no problem with the hydraulic relief valve, but there was also no problem with the installation method and operation. Now Jimmy is depressed. The owner is pushing for status, but he has no clue. He contacted with several local hydraulic valve manufacturers in the United States, and they all replied that there was no problem on the hydraulic relief valve. One day, after browsing AAK website (www.aakindustry.com) in Google, Jimmy sent an email asking if AAK could help analyze the reason. We replied that it would be better for engineers to have video communication on site Jimmy decided to ask Vickers engineers to make a video with AAK engineers the next morning. After more than half an hour of observation, AAK engineers found that once the pressure oil at the inlet, outlet and control port of the hydraulic relief valve fluctuated, it would produce a scream. We got their original samples and drawings, as well as the working parameters of the hydraulic pump. After 15 days, AAK sent a sample of the pilot hydraulic relief valve. A week later, Jimmy e-mailed us that AAK hydraulic relief valve was installed and tested on site for 24 hours, and there was no scream. Jimmy wondered why there was no scream when AAK hydraulic relief valve was used. AAK engineers analyze the cause from the hydraulic impact. After the hydraulic pressure impacts the main valve spool in the hydraulic relief valve, the pressure oil converges through the check valve, resulting in fluid impact and fluctuation, causing the hydraulic relief valve to oscillate, resulting in the instability of the pressure oil at the outlet of the hydraulic pump. Because the pressure oil output by the pump itself has pulsation, the pressure oil output by the pump will fluctuate strongly and arouse the vibration of the hydraulic relief valve. For the natural frequencies of the two hydraulic relief valves are the same, it causes the resonance of the relief valve and the scream occurs.
Martin, a purchaser of American company PowerTeam, sent an email last week saying that he saw on the Internet that AAK was a hydraulic valve supplier of some European hydraulic pump companies. He wanted to know whether the quality of AAK could match the quality of the hydraulic valve produced in the United States he was currently using. I directly answered that the quality of hydraulic valves in the United States should also be in different levels, you can have a small try and compare them with your hydraulic valves purchased in the United States. Martin frankly told about his current purchasing status. He needed to re-purchase a batch of hydraulic sequence valves for hydraulic pumps. After placing an order with the original manufacturer in the United States, the manufacturer told him that there were not enough labor for mass production at this moment. He had to wait for 3 months at least. The owner was not satisfied with his purchasing arrangement and asked him to find a new supplier of hydraulic sequence valve and complete production within 2 months. Martin is a little embarrassed because this hydraulic sequence valve has particularly high requirements for various accuracy. In the early stage of development 3 years ago, he contacted more than 20 hydraulic valve manufacturers, compared and tested the hydraulic sequence valves from them, and only the samples from the local hydraulic valve manufacturer in the United States met the requirements. Martin saw the information of AAK to found that it was actually the supplier of hydraulic pumps in Europe. After browsing AAK website (www.aakindustry.com), he felt that AAK hydraulic valve might become his supplier. According to the drawings and working conditions of his hydraulic sequence valve, we found that it does have high requirements for the accuracy of the hydraulic sequence valve. I told Martin that we need 15 days to make and test samples. After the samples of the hydraulic sequence valve pass the test, we will discuss the order at that time. 10 days after the hydraulic sequence valve sample was sent, Martin emailed AAK that the hydraulic sequence valve fully met the production requirements of the existing hydraulic pump. At the same time, the engineers of PowerTeam also applauded every detail of AAK hydraulic sequence valve sample, which was no worse than that of the American company. In particular, some core parameters, such as the matching surface roughness of AAK hydraulic sequence valve spool and valve hole, can reach Ra value of 0.1 ~ 0.2�¼m. The surface roughness Ra value of the outer circle of the valve spool is 0.1m. The Ra value of the inner circular surface of the valve hole is 0.2m. Some parameters are even higher than those of his original American manufacturer, including 100% burr removal.
On Monday afternoon, I received an email from Tony. Tony is a purchasing manager of CASAPPA in Italian, mainly responsible for the purchasing of hydraulic pump components, and the work has been very smooth. Last month, they received a complaint from the largest customer that the pressure at the outlet of the hydraulic pump sometimes rises by itself, resulting in unstable operation of the equipment. The customer's site engineer couldn't solve it and turned to CASAPPA for after-sales service. Although the warranty period has expired, they still need to help customer solve the problem. Their engineers tested various parameters of the hydraulic pump. After comprehensive analysis, they were still uncertain about the root cause, but they suspected that the hydraulic pressure relief valve in the pump is faulty. The engineer asked Tony to contact the original supplier of the hydraulic pressure relief valve and ask him to send a sample of the hydraulic pressure relief valve for replacement and test. It is a local hydraulic valve manufacturer and they still have samples in stock. After receiving samples and commissioning, the engineer's suspicion was proved to be correct. After replacing the hydraulic pressure relief valve, the hydraulic pump worked normally. Tony asked the original hydraulic valve manufacturer to urgently replenish 30 hydraulic pressure relief valves to solve this complaint. The manufacturer said that the shipment has passed the two-year warranty period. At present, there are only 3 samples in stock. The remaining quantity needs to wait in production schedule for production, and can only be delivered after 3 months. If offering this plan to the big customer, Tony would be scolded by the boss. He thought of AAK, because the hydraulic valve failed last year, which was also solved by AAK. Tony established a business relationship with us last October. Now we are also friends besides business. We often discuss the knowledge related to hydraulic valves. His email on Monday is just to ask for help on this hydraulic pressure relief valve. After knowing these conditions, I asked him to send us samples of those faulty hydraulic pressure relief valves, and provide us the drawings of this hydraulic pressure relief valve, noting those special requirements. After receiving and disassembling the samples from Tony, we found that the main valve spool of the hydraulic pressure relief valve was too loose and had increased leakage, then the pressure at the oil outlet increased. The problem should be caused by high-frequency wear or insufficient accuracy of the original shipped hydraulic pressure relief valve. The engineer of CASAPPA asked us to reply why it was determined that it was the problem of the valve spool?
On Monday afternoon, I received an email from Tony. Tony is a purchasing manager of CASAPPA in Italian, mainly responsible for the purchasing of hydraulic pump components, and the work has been very smooth. Last month, they received a complaint from the largest customer that the pressure at the outlet of the hydraulic pump sometimes rises by itself, resulting in unstable operation of the equipment. The customer's site engineer couldn't solve it and turned to CASAPPA for after-sales service. Although the warranty period has expired, they still need to help customer solve the problem. Their engineers tested various parameters of the hydraulic pump. After comprehensive analysis, they were still uncertain about the root cause, but they suspected that the hydraulic pressure relief valve in the pump is faulty. The engineer asked Tony to contact the original supplier of the hydraulic pressure relief valve and ask him to send a sample of the hydraulic pressure relief valve for replacement and test. It is a local hydraulic valve manufacturer and they still have samples in stock. After receiving samples and commissioning, the engineer's suspicion was proved to be correct. After replacing the hydraulic pressure relief valve, the hydraulic pump worked normally. Tony asked the original hydraulic valve manufacturer to urgently replenish 30 hydraulic pressure relief valves to solve this complaint. The manufacturer said that the shipment has passed the two-year warranty period. At present, there are only 3 samples in stock. The remaining quantity needs to wait in production schedule for production, and can only be delivered after 3 months. If offering this plan to the big customer, Tony would be scolded by the boss. He thought of AAK, because the hydraulic valve failed last year, which was also solved by AAK. Tony established a business relationship with us last October. Now we are also friends besides business. We often discuss the knowledge related to hydraulic valves. His email on Monday is just to ask for help on this hydraulic pressure relief valve. After knowing these conditions, I asked him to send us samples of those faulty hydraulic pressure relief valves, and provide us the drawings of this hydraulic pressure relief valve, noting those special requirements. After receiving and disassembling the samples from Tony, we found that the main valve spool of the hydraulic pressure relief valve was too loose and had increased leakage, then the pressure at the oil outlet increased. The problem should be caused by high-frequency wear or insufficient accuracy of the original shipped hydraulic pressure relief valve. The engineer of CASAPPA asked us to reply why it was determined that it was the problem of the valve spool?
AAK uses endoscope C50 to detect the internal burr of the hydraulic valve block, and then sprays the burr remaining in the hydraulic valve block with high-pressure solution, so that there is nowhere for the burr to hide. Nearly 95% of domestic hydraulic valve manufacturers are not equipped with endoscope and ignore 100% removal of the residual burr of the hydraulic valve block. The American customer who has suffered a loss elsewhere chose to order from AAK again. Most domestic hydraulic valve manufacturers use conventional physical methods to deal with the burr of hydraulic valve block, and check whether the burr is cleaned by experience, especially the burr of deep hole or magnetic burr, which can hardly be cleaned. It is common that the defective rate of hydraulic valve block exceeds the standard due to human error. At the beginning of last year, we received an inquiry for hydraulic valve block from Hunter, an American customer. We calculated the price according to his hydraulic valve block drawings. Hunter was not satisfied with our quotation. Because the communication was very pleasant, I wanted to make friends with hunter and gave up my commission to adjust the price. Hunter frankly said that although the new price of AAK hydraulic valve block meets his target price, the prices of other hydraulic valve manufacturers are still cheaper than those of AAK. We can only withdraw from the purchase of hydraulic valve block amicably. If something goes unusual, there will be problems. 2 months later, Hunter came back to us and said that he was very willing to accept our quotation for hydraulic valve block. He informed that there were different degrees of burrs at the internal cross holes of the hydraulic valve block samples proofed by the original hydraulic valve manufacturer. The hydraulic valve block samples were modified 3 times. Each time the cartridge valve was installed and debugged, the valve spool was stuck from time to time. The factory has also conducted commissioning for many times, and has been unable to remove burrs for 100%. He can only give up this hydraulic valve manufacturer and came back to AAK. Burr must be produced in the drilling process of hydraulic valve block, which is very harmful to the hydraulic system. In addition to adopting appropriate treatment process for burr removal, it is also necessary to have relevant auxiliary testing equipment to guarantee the complete 100% removal of burr. Hunter asked us to arrange approval samples of hydraulic valve block immediately. After 15 days, we sent the hydraulic valve block samples. On the 3rd day after Hunter received the samples, he sent an email to inform AAK that the samples passed testing at one time. Hunter admired that AAK can get the hydraulic valve block samples approved at one time that the peer can't get approval at 3 times. At the same time, he also expressed his curiosity about how AAK can accurately remove the burrs?
One morning in the first half of this year, shortly after arrived at the company, the owner asked him to come to his office. He realized whether there was a complaint about the hydraulic valve. He saw that the technical director was also in the owner's office. It turned out that the hydraulic check valve installed on the hydraulic pump had leakage in different proportions. These hydraulic pumps were due to ship in 20 days. The owner asked him to purchase the qualified hydraulic check valve in 40 days, because their customer only gave the company a 4-week extension. The technical director informed that according to the on-site detection, about 20% of the hydraulic check valves had leakage. After dissection, it was found that the gap between the valve body hole and the valve spool of these leaking hydraulic check valves was uneven, and some even exceeded 40m. The gap dimensions are quite different. Sam immediately contacted the original hydraulic valve manufacturer and asked him to replenish 30% to replace those unqualified hydraulic check valves, but he was rejected. Per the original hydraulic valve manufacturer, these hydraulic check valves passed the inspection before delivery and the leaked hydraulic check valves were caused by their improper installation. In the end, the manufacturer didn't even reply to his email. was angry and had to find a new supplier of hydraulic check valve. which made him see the dawn and feel that hydraulic valve is different. He emailed us inquiry about the hydraulic check valve and truthfully informed us of the problems he encountered with the Chinese hydraulic valve manufacturer. After several rounds of and operating conditions provided by , promised him to offer qualified hydraulic check valve samples within 14 days. If the samples are qualified, the 30% of quantity that he needs can be delivered in 4 weeks. After 14 days, received the hydraulic check valve samples. There was no leakage after installation and commissioning, and the gap between the valve body hole and the valve spool of each hydraulic check valve could be stable within a range and uniform in size. The technical department told him that the standard deviation (sigma) accuracy of the clearance dimension of hydraulic check valve was more than 3 times higher than that of the original supplier. was surprised how hydraulic valve was different The whole line of production equipment of hydraulic valve is a high precision machine tool and processing center
Kate, the buyer of Terex company, was asked by the head office last month to purchase a batch of hydraulic pressure valves within 3 months. She vowed to the owner that it would be completed in 2 months. As usual, Kate sent the hydraulic pressure valve inquiry to more than 10 hydraulic valve manufacturers she was familiar with, including American hydraulic valve manufacturers and Chinese hydraulic valve manufacturers. She chose 3 factories to provide hydraulic pressure valve samples for testing. After the test, the technical department informed that only the hydraulic pressure valve samples provided by American manufacturer were qualified. The trouble is that the price of the qualified hydraulic pressure valve exceeds 40% of the company's budget price. She has no authority to decide to use the products of this American hydraulic valve manufacturer. After discussion with the technical department, she learned that those unqualified hydraulic pressure valves are mainly due to the wear or fracture of the sealing ring after 15,000 times of impact during the durability test of the hydraulic pressure valve, resulting in the leakage of the hydraulic pressure valve. Only those hydraulic pressure valves that have not leaked for more than 40,000 times are qualified. She was very depressed that the quotation of the other 3 hydraulic pressure valves was within the budget, but the quality was unqualified. At this time, Kate realized why the company gave him 3 months to purchase. She hurriedly sent inquiry to new hydraulic valve manufacturers, and specially emphasized the need for hydraulic pressure valves with more than 40,000 durability tests. The trouble is that no hydraulic valve manufacturer gave her an offer. Kate realized the difficulty of procurement. She had wasted 3 weeks. Procurement was still in its infancy, and the technicians had been urging progress. After learning about Kate's purchase status, the colleague recommended her to contact AAK HYDRAULIC VALVE to try. When we received the hydraulic pressure valve drawing from Kate, we first gave a quotation. She told us very frankly that the price of AAK was 20% higher than that of other China hydraulic valve manufacturers, but 15% cheaper than that of the United States. She needed us to reduce the price greatly. We suggested providing the hydraulic pressure valve samples for testing first, and then discuss the price after passing the test. 2 weeks later, Kate informed that the test was qualified and AAK hydraulic pressure valve durability test had reached more than 40,000 times. She was surprised why AAK passed the hydraulic pressure valve durability test, while the other hydraulic valve manufacturers in China failed. AAK hydraulic valve was also eliminated by customers 2 years ago because the durability test of hydraulic pressure valve failed to meet the standard.
Early last month, I saw an email from Mark, the purchasing manager of hydraulic system of Caterpillar, an old friend of ours. The subject of the email is "I need help from AAK, I believe". After reading the email about hydraulic threaded cartridge valve, I understood Mark's embarrassment. A small less-known excavator designed by them at the beginning of this year was not smooth in the commissioning process, the response of the excavation part was slow and the power was not enough. After testing, the technical department found that the measured value of the maximum overflow pressure was lower than the specified value, so it was determined that there was a problem with the hydraulic threaded cartridge valve. Mark communicated with the original hydraulic valve supplier. The supplier mentioned that the hydraulic threaded cartridge valve was sampled according to their company's drawings, and all parameter tests were up to standard. The supplier told the fact. He then could only patiently communicate with the design department to see how to modify the hydraulic threaded cartridge valve design, but the design Department said that there was a problem with the installation of the technical team. The company's design and technology departments prevaricate with each other and Mark are caught in the middle, which is very embarrassing and time is also being wasted. If the owner is angry one day, it is estimated that all 3 parties will be criticized. AAK HYDRAULIC VALVE has always been Mark's most trusted supplier of hydraulic valves. I asked Mark to send us the original design drawings of the hydraulic threaded cartridge valve and the working condition requirements of existing equipment, as well as the problems and data encountered in commissioning. 3 days later, we replied to Mark that we have a new design scheme, and we are 90% sure that we can make the hydraulic threaded cartridge valve that meet the equipment requirements, but it will take 2-3 weeks. On the 3rd day after receiving our sample of the hydraulic threaded cartridge valve, Mark happily informed us that the technical department tested AAK hydraulic threaded cartridge valve, the equipment commissioning was smooth, and the reaction and power of the excavation part were normal. The technical department said that the large goods of this hydraulic threaded cartridge valve can only come from AAK, and other hydraulic valve manufacturers are unreliable. Caterpillar designers are also curious about how AAK HYDRAULIC VALVE redesigns this hydraulic threaded cartridge valve? AAK engineering team tried 30 times to design, sampling and make adjustment to find a breakthrough. A sealing ring groove is arranged between the oil replenishment outlet and the oil replenishment inlet of the oil replenishment valve seat of the hydraulic threaded cartridge valve.
AAK hydraulic valve block adopts multi edge particle cutting with diamond reamer, the accuracy can reach 0.002mm, and the surface roughness can reach Ra 0.2um, the precision is twice that of other hydraulic valve manufacturers, and there is no iron filings. Because the price of AAK hydraulic valve block is a little higher than that of peers, LIEBHERR excluded AAK from the supplier list. However, 3 months later, LIEBHERR still placed an order for the hydraulic valve block with AAK. This morning, I received an order for hydraulic valve block from Herta from LIEBHERR company in Germany, which was a little unexpected. Because this is the hydraulic valve block that AAK sent sample for 3 months ago. Since the sample was sent, there was no news about the sample. After several follow up emails, the reply was "unqualified". I asked about the reason why the hydraulic valve block was unqualified, but didn't get reply. Now I can't understand why the order comes to us 3 months later. Herta is mainly responsible for the procurement of hydraulic accessories of LIEBHERR. In the first half of this year, his company needed to purchase a batch of high-precision hydraulic valve blocks for hydraulic excavators. At that time, he selected 5 hydraulic valve factories to send samples to test the quality and conduct assembly tests. 3 months later, after comprehensive comparison, their technical team found that the test data of AAK hydraulic valve block was the best among the 5 hydraulic valve manufacturers. I asked Herta curiously why the reply he gave us 3 months ago was "unqualified". He replied that your quotation was unqualified and more expensive than the other 4 hydraulic valve manufacturers, so we judged AAK to be unqualified. After 3 months of testing, the technical team believes that AAK's hydraulic valve block has the highest precision, the strongest durability and the simplest follow-up maintenance. Although the price of AAK is a little higher than that of other suppliers, according to the comparison of various parameters, the hydraulic valve block of AAK can enable LIEBHERR to reduce the cost of subsequent maintenance, so the technical department designated AAK to supply this hydraulic valve block. Herta asked us why some parameters of AAK hydraulic valve block are twice better than those of peers? The high precision of AAK hydraulic valve block mainly comes from the diamond reamer used in AAK machining center, which is a multi edge particle cutting. In the reaming process, the chips are hidden between the diamond particles and thrown out via coolant flushing and high-speed rotation, so that the chip removal in the first step is complete.
In this year, , an customer, visited 5 hydraulic valve factories before and after, and made samples of hydraulic relief valve with 1m inner hole for 3 times, but none of them reached the accuracy requirements. sent samples and met the standard for the 1st time, finally chose to cooperate with . The inner hole accuracy is not enough, which is mainly caused by the different built in equipment of honing machines equipped by many hydraulic valve manufacturers. Conventional honing machines use diamond reamers., Because the main cutting part of the diamond reamer is at the tool head, the tool head wears quickly. After the head is worn, it is very easy to cause the size of the hole bottom to be small, resulting in the poor cylindricity of the whole hole and affecting the accuracy. This is the key to the 5% accuracy error. Many hydraulic valve manufacturers are not aware of this key point. , a purchaser from a hydraulic valve in , has an inquiry for a special hydraulic relief valve, and the inner hole accuracy must be controlled within 1m. checked with the original hydraulic valve supplier, and got reply that only the hydraulic valve manufacturer equipped with high precision honing machine is able to make the hydraulic relief valve with 1m inner hole accuracy. According to the equipment configuration, has contacted with more than 10 hydraulic valve manufacturers, determined to visit 5 hydraulic valve manufacturers, and asked 3 powerful factories to sample the hydraulic relief valve. After testing and comparing the samples received from these 3 hydraulic valve factories, all failed to meet the standard. asked the manufacturer with the highest accuracy to continue to improve the proofing, and there is still 0.1m gap. The factory gave up and introduced HYDRAULIC VALVE to him, maybe can do the hydraulic relief valve with 0.1m inner hole accuracy. According to his hydraulic relief valve drawing, we advised that we can send 1pc hydraulic relief valve quality sample after 10 days. 5 days after successfully sent the hydraulic relief valve sample, Bowen informed that the accuracy met the standard. He wanted to know why so many hydraulic valve manufacturers could not achieve 1m inner hole hydraulic relief valve, even if the hydraulic valve manufacturers promised to do so and they also have high precision honing machines, but several proofing did not meet the standard. How did hydraulic valve achieve it Honing machine is really helpful for the machining of high precision inner hole. Due to different equipment configuration, not every hydraulic valve manufacturer can produce the hydraulic relief valve with 1m inner hole accuracy.
In March this year, the sales manager of Caterpillar received a phone call from a Spanish customer complaining that several excavators produced by their company had small start-up faults. The repairman judged that the hydraulic system leaked oil, which should be caused by the leakage of the hydraulic check valve. The customer asked them to replace the hydraulic check valve as soon as possible. This customer accounts for 40% of Caterpillar's sales. Although it has passed the maintenance period, they must help the customer solve the problem. The original hydraulic valve supplier said that for the hydraulic check valve under this working condition, there can only be no leakage for 2-12 months. In extreme cases, it may be less than 2 months. The customer was disappointed with such a maintenance plan. The owner asked Mark, the purchasing manager, to find a solution satisfying the customer. Mark contacted more than 10 hydraulic valve manufacturers, but did not get a satisfactory reply. He owner urged him to make a new plan twice a day. Mark thought of AAK HYDRAULIC VALVE he had contacted before. Maybe AAK can do some help. He firstly asked us why so many hydraulic valve manufacturers can't achieve 0 leakage for more than 12 months for this style of hydraulic check valve? The hydraulic check valves often use steel ball or metal cone slide valve to contact and compress with the orifice of metal valve seat under the action of spring and fluid pressure to prevent the reverse flow of liquid, but it is difficult to achieve absolute seamless butt joint in the cutting of metal contact surface. Especially under the special working condition of this customer, it is more difficult to avoid leakage. This hydraulic valve manufacturer who has insured for 2 months is already great. Mark thought that AAK HYDRAULIC VALVE could not produce a hydraulic check valve with 0 leakage for more than 1 year, and asked how long we could insure at most. AAK can produce hydraulic check valve with 0 leakage for more than 12 months. If there is no leakage within 1 month, and if subsequent maintenance is in place, the hydraulic check valve can be 0 leakage for 24 months. Mark was surprised at our reply and thought we were joking. Let's talk about it with facts: AAK will send the hydraulic check valve samples within 20 days, you test the hydraulic check valve first, and we will then discuss it after the test. After 15 days, AAK sent the hydraulic check valve samples to Caterpillar. Their engineers conducted internal test first, and there were no abnormalities in many tests. Their after-sales personnel took the samples directly to the customer's construction site for on-site installation and commissioning. It worked continuously for 12 hours, and everything was still normal.
Recently, the same model of hydraulic valve spool, has higher precision and stronger sensitivity than its peers. This is a good question. I smiled and said you may not have a comprehensive understanding of hydraulic valve. For all types of hydraulic valve spools, is subject to strict quality control. Under the condition of ensuring that the spool is suitable for the service conditions, we will select the most appropriate tool steel 40Cr, Cr12MoV, 12CrNi3A, 18crniwa and GCr15, etc according to the customer's parameter requirements and service scenarios. 6 major processing processes and 6 major parameters are used. This technology has led the industry, we are not satisfied with these static data, but also need dynamic spool. Since the valve spool needs to move in the valve body, the clearance between the valve spool and the valve body should not only ensure good sealing, but also ensure small movement resistance. Therefore, the matching clearance between the valve spool and the valve body is the top priority affecting the use of the valve spool. The following are the tolerances and matching clearance dimensions of the valve spool and the valve body produced in large quantities by in the actual production process Diameter Valve body tolerance Spool tolerance Minimum clearance Maximum clearance 6mm 0.006mm 0.004mm 0.0025mm 0.0125mm 6-12mm 0.0075mm 0.005mm 0.0050mm 0.0175mm 12-20mm 0.01mm 0.006mm 0.0050mm 0.0233mm 20-25mm 0.0125mm 0.0075mm 0.0125mm 0.0325mm When the reciprocating or rotary valve body is matched with the valve spool, we generally use the minimum clearance, but the specific processing parameters should also be determined according to the customer's parameter requirements and use scenarios, so as to ensure that the hydraulic valve does not have any leakage, valve stuck and other unexpected working conditions. During the processing and manufacturing of valve spool, also strictly considers the following aspects, and will check and test each valve spool when necessary, so as to ensure the high quality and reliability of valve spool. Hydraulic power on hydraulic spool Pressure and flow characteristics of hydraulic valve spool Flow coefficient of hydraulic valve spool Leakage of hydraulic valve spool Stability of hydraulic valve spool Vibration of hydraulic valve spool Cavitation of hydraulic valve spool After listening, they admired rigid attitude and trusted the quality of hydraulic valve more. Using hydraulic valve is reassuring, so has always been their preferred hydraulic valve supplier in . hydraulic valve sticks to itself and high quality control. You can also have a small try AAK HYDRAULIC VALVE (114) 2021-12-08
mainly responsible for the purchasing of hydraulic pump components. Last October, developed a new hydraulic pump and planned to promote this new product at this year's exhibition. During the debugging, the output pressure of the hydraulic pump can not be established several times, which is a little troublesome, because the owner has sent all the invitations to the exhibition to the customers and grandly introduced the functions of this hydraulic pump. The R & D personnel checked and tested each component one by one. It is basically certain that it is caused by the instability of the pilot operated pressure control valve. The technical team dissected the pilot pressure control valve and found local friction marks on one side of the hole wall of the valve body. The diagnosis conclusion is that the main valve spool is stuck, which should be caused by the concentricity difference between the hole of the main valve body and the hole of the pilot pressure control valve body. to re purchase the pilot pressure control valve that meets the technical requirements, which must be solved within 25 days, otherwise he will leave because the exhibition is too important. the original hydraulic valve manufacturer and got a reply that due to equipment, he could not produce high-precision pilot pressure control valves with the exactly same concentricity. At the same time, he contacted a number of hydraulic valve suppliers and they basically replied that they could not do such a high precision pilot operated pressure control valve, which made almost . When searched the hydraulic valve suppliers in , he found AAK HYDRAULIC VALVE. The details page of the hydraulic valve on AAK made feel that maybe AAK could have a try. He emailed us firstly to ask whether the concentricity of the pilot operated pressure control valve could be consistent. We need the detailed drawings, working conditions and parameters of his whole hydraulic pump to judge. After receiving all information from him, AAK technical team pondered the whole afternoon, with more than 95 confidence, and it would take 15 20 days to complete it. he was happy and uneasy. He was happy that some hydraulic valve manufacturer could try this high-precision pilot operated pressure control valve and has a high probability of success. He was uneasy that if AAK HYDRAULIC VALVE did not succeed in proofing, the time would be wasted. We understand his concern. We told him that the reason why we are not sure for 100 is that there is a data that can't be determined. If AAK HYDRAULIC VALVE failed in sampling, then he should not waste time in Ningbo area. We suggest that he also find a hydraulic valve supplier in Europe, so as to sample with AAK at the same time.
When I got up to go to the bathroom at 1 a.m. last Monday, my wechat phone rang. It was from Carl, the purchasing manager of Denison hydraulic pump company in the United States. I was very surprised by this phone call. Generally, we communicate with Carl in the form of e-mail and have never used wechat phone. Carl firstly said sorry to disturb my rest, and asked if I could arrange a video conference at 8:00 tomorrow morning. He needs to discuss a troublesome problem with our technical team. I'm concerned that the communication on the phone will not be clear, and asked him to send me a written email first, and then I'll reply to him. Half an hour later, a detailed email with a schematic diagram of the hydraulic system came in. Last week, the hydraulic pump supplied by them encountered problems with his customer. The customer's hydraulic system has been shelved for half a year, and now it needs to be driven. After the operator starts the hydraulic pump, there is no pressure in the hydraulic system. The field engineer judged that there was no flow output of the hydraulic pump, but after inspection, it was found that the rotation direction of the motor was consistent with that of the hydraulic pump, and the oil level, oil temperature and viscosity of the hydraulic pump met the working conditions. The suction system of the hydraulic pump was replaced, including the oil suction pipe and filter. After startup, there was still no flow output. The transmission parts inside the hydraulic pump are intact without falling off, fracture and blade jamming. A week has passed and no reason has been found. Because the hydraulic pump is still in the warranty period, if it cannot be solved in another week, it can only be returned for claim. Carl asked the original supplier of each part for the hydraulic pump and got nothing. After reading the email, I asked him if the hydraulic pump used a hydraulic check valve? Carl said that the hydraulic check valve was provided by HAWE company in the United States, but the after-sales period of the hydraulic check valve has expired. Because AAK supplied hydraulic check valves to their company last year, and the quality was very satisfying, although the hydraulic check valve in this hydraulic pump is not from AAK, he wants to see if AAK technical team can find out the reason. I said there was no problem with the 8:00 video conference tomorrow, because the chief engineer of AAK didn't travel, but I'm not sure if we can help. The next day in the video conference, their engineers showed the whole system. Our chief engineer found that the displacement of the hydraulic pump was 8ml / R, so he asked them to fill the hydraulic pump directly in the oil outlet pipeline, and then start it up. The hydraulic pump still had no flow.
James is the purchasing director of one of our American Hydraulic customers. They are the top 3 in the construction machinery industry in the United States, and their market share is increasing year by year. James is also doing well. In May last year, the MP550-HDD-18 cement delivery pump supplied by their company to a local construction company often failed to reach the rated value for the system pressure during use, and the oil pressure of the hydraulic system can only reach 12MPa. After disassembling the hydraulic system, the engineer found that the joint surface between the conical pilot valve body and the valve seat of the hydraulic relief valve was grinded out with a circle of uneven groove line with a depth of about 1mm for unknown reason. The hydraulic oil flowed back to the oil tank from this groove, and the hydraulic relief valve had no sealing function. The customer wanted Jamesâ??s company to replace the hydraulic relief valve of the same model within 2-3 weeks. If they miss the time, the project progress will be affected. When James purchased this hydraulic relief valve from the original German hydraulic valve supplier again, he was told that they produce this hydraulic relief valve no longer. If he wanted to re-produce it, it would take 35 days and modify the production process and auxiliary equipment, which would require an additional cost of more than 30,000 US dollars. This style of hydraulic relief valve was just purchased by James 2 years ago. When he reported this situation to the president, the president didn't understand why he didn't have an alternative hydraulic valve manufacturer. James realized that the president was unhappy. When he sent the anatomical drawing of this hydraulic relief valve to more than 20 hydraulic valve manufacturers, almost all said that they have no hydraulic relief valve with such structure, James was a little flustered. In March this year, James just purchased a batch of high-precision hydraulic relief valves from AAK. He wanted to see if AAK had a way to solve this thorny problem. When he sent us the pictures of this hydraulic relief valve made in Germany, we asked him to send us the whole complete technical drawings, as well as the use environment and working conditions. The pressure of this hydraulic relief valve is 31.5Mpa and the flow is 200L / min, which is basically consistent with the parameters of the hydraulic relief valve we supplied to them before. However, there is a fatal problem that the internal structure, appearance, shape and size are inconsistent with those of the hydraulic relief valve they purchased in Germany, so it is difficult to install on the transmission line. After learning that the only way is to meet the requirements of the transmission line at the construction site in the United States, AAK engineers designed a new hydraulic system with two pipe joints and an oil plug according
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.
Some time ago, , from a Hydraulic Valve Company in UK, fell in a batch of hydraulic directional valves purchased in Ningbo. There had some email communication between HYDRAULIC VALVE and , but maybe the fate has not yet arrived, we did not cooperate until last month this year. Steven regained his confidence because he had suffered a waterloo and got back a key game here in . At the beginning of this year, a batch of hydraulic directional valves purchased by Steven in Ningbo were stuck and failed during the test run, resulting in the failure of the whole batch of equipment to start up and run. His customer asked UK company to solve it within 30 days, otherwise there will be a big claim. Steven informed the original hydraulic valve manufacturer of these conditions, but the manufacturer prevaricated that it was a problem caused during the assembly process and had no direct relationship with them. Steven also consulted other hydraulic valve manufacturers. They either replied that the hydraulic valve was not produced by them and could not give the corresponding strategy, or there was no reply. Steven received serious rebuff here and there, and feel stressed. When contacted HYDRAULIC VALVE, we were willing to cooperate with him to solve this problem because we felt his trust in HYDRAULIC VALVE. Through his email description, we were still not sure what the problem is, and asked him to send us samples. After HYDRAULIC VALVE received the hydraulic directional valve samples from Steven, we felt that the relative sliding between the middle valve column and the valve body was not smooth. When the whole hydraulic directional valve is disassembled, there are slight scratches on the column surface, the valve body hole has a negative tolerance, and the valve body column hole has plastic distortion. Further microscopic examination showed that the surface of the material was etched badly. It is certain that the original hydraulic valve manufacturer has problems in material selection and heat treatment of alloy steel. Then we informed Steven of the result in a report and attached our suggestions for this style of hydraulic directional valve. After receiving the report, Steven seemed to see hope and asked us to make 5 hydraulic directional valve samples for his customer to run successfully first. After knowing the working conditions of this hydraulic directional valve, we adjusted the material selection of alloy steel, and increased the overall hardness of the hydraulic directional valve by 30% on the original basis. week after Steven received the samples, he informed HYDRAULIC VALVE by e-mail that the hydraulic directional valve samples made by were started up smoothly as soon as they were tested on the machine. When the new delivery date and order quantity were confirmed by his customers, he was finally relieved.
