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  • Dervos 15th Anniversary Celebration Held in Beijing
    Dervos 15th Anniversary Celebration Held in Beijing Aug 04, 2023
    We are thrilled to announce that Dervos has held a momentous celebration in Beijing, commemorating the company's remarkable 15-year journey. The joyous gathering brought together clients from different countries, forging deeper connections and strengthening the bonds between Dervos and our valued partners. It was a heartwarming occasion to express our sincere gratitude for the trust they have placed in us over the years. During the event, Dervos' founder Eric and Ken expressed heartfelt gratitude to clients, their valuable insights and feedback continuously inspire us to improve our products and services, allowing us to stay at the forefront of the industry. At Dervos, we take great pride in recognizing and supporting our employees' growth. With a team of experienced professionals, we strive to provide outstanding services to our clients. Dervos proudly recognized two remarkable employees, Jona and Susie, for their five years of dedicated service. The custom-crafted rings and necklaces, bearing their names and heartfelt wishes, symbolize our appreciation for their valuable contributions. In addition, we curated eight dragon-shaped molds, each concealing intriguing surprises. Once everyone selected their preferred dragon, they eagerly commenced the excavation process, which proved to be an engaging physical activity. After a brief endeavor, each participant successfully unearthed their coveted treasure: personalized seals with their names intricately engraved, adding a profound sense of commemoration to the occasion. We were delighted to receive heartfelt wishes from our customers. During the event, we invited them to inscribe their blessings to Dervos on Xuan paper and seal it with their personal stamp. To mark the occasion, Eric and Ken imprinted Dervos' seal, symbolizing the enduring bond between Dervos and our partners. This act beautifully encapsulates the spirit of unity and mutual commitment, reaffirming that Dervos and our partners will stand together through the test of time. Amidst the jubilant ambiance, the Dervos team couldn't resist showcasing their individual talents. West's soulful voice filled the air with a captivating song, while Sheila mesmerized the audience with her fiery dance performance. The infectious spirit of celebration inspired everyone to join in the revelry, creating a harmonious dance ensemble as they moved in sync with the joyful rhythm. Reflecting on the past 15 years, Dervos has achieved significant milestones and overcome numerous challenges, growing from strength to strength. Our commitment to excellence, innovation, and customer satisfaction has been the driving force behind our enduring success in the global market. Dervos looks forward to many more years of shared success with our esteemed clients, as we continue on this remarkable journey together.
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  • Dervos Annual Tour - Beijing Station
    Dervos Annual Tour - Beijing Station Jul 19, 2023
    Every year, Dervos prepares a cultural trip for employees. After everyone's vote this year, Beijing stood out. As the capital of China, Beijing is a city with a long history and culture, with numerous historical sites and cultural landscapes. Among them, everyone is familiar with Tiananmen, the Palace Museum, Yuanmingyuan Park, the Prince Gong's Mansion, the Temple of Heaven, the Great Wall and so on. This time we have eight days to follow the tour guide's footsteps, gradually appreciate the beauty of the buildings, and listen to the historical changes. During our trip, Beijing reached a rare high temperature of 40°C. But everyone's enthusiasm for visiting remained unwavering. For this reason, everyone encouraged each other and helped each other, not only challenged themselves, but also conquered the high temperature. As the saying goes, "He who does not reach the Great Wall is not a true man. "So we ended our trip with the project of climbing the Great Wall. The weather that day was very bad, with strong winds and heavy rain, which brought us many difficulties in climbing. But the Dervos people challenged themselves, never gave up, and successfully reached the pinnacle. Work hard, play hard. This trip allows everyone to break free from busy work, adjust their state, and better immerse themselves in work.
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  • What are the Characteristics that Valve Sealing Surface Materials Should Have?
    What are the Characteristics that Valve Sealing Surface Materials Should Have? Jun 16, 2023
    The sealing surface of the valve is a vulnerable component of the valve due to frequent corrosion, erosion, and wear from the medium. Automatic valves such as pneumatic ball valves and electric butterfly valves have frequent and fast opening and closing speeds, and the quality of their sealing surfaces directly affects the service life of the valves. The basic requirement for valve sealing surface is to ensure safe and reliable sealing under specified working conditions. Therefore, the material of the valve sealing surface should have the following characteristics. 1. Good sealing performance. The sealing surface should be able to effectively prevent the leakage of the medium; 2. A certain strength. Under the action of medium pressure difference, the sealing surface should be able to withstand the sealing specific pressure value formed by it; 3. Corrosion resistance. The sealing surface should have strong corrosion resistance that is suitable for the design requirements under the long-term action of corrosive media and stress; 4. Ability to resist scratches. The valve sealing pairs are all dynamic seals, and there is friction between the sealing pairs during the opening and closing process; 5. Erosion resistance. The sealing surface should be able to resist the erosion of high-speed media and the collision of solid particles; 6. Good thermal stability. The sealing surface should have sufficient strength and antioxidant capacity at high temperatures; At low temperatures, it should have good resistance to cold brittleness; 7. Good processing performance. Easy to manufacture and maintain, the valve functions as a universal component, ensuring economic value.
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  • How to Install the Valve Gasket?
    How to Install the Valve Gasket? Jun 07, 2023
    Sealing gasket is a commonly used sealing spare part for machinery, equipment, etc. It is a material that plays a sealing role. Correct installation can ensure sealing performance and smooth operation of the equipment, otherwise it will damage the sealing gasket. Next, let's take a specific look at what to do. The correct installation of gaskets should be carried out when the flange connection structure or threaded connection structure, sealing surface, and gasket have been inspected without any doubt, and other valve components are intact and undamaged. 1. Before installing the gasket, apply a layer of graphite powder or lubricant mixed with engine oil (or water) to the sealing surface, gasket, thread, and rotating parts of the bolt and nut. The gasket and graphite should be kept clean. 2. The gasket should be installed on the sealing surface in a moderate and correct manner, without deviation, and should not extend into the valve chamber or rest on the shoulder. 3. Only one gasket is allowed to be installed, and it is not allowed to install two or more gaskets between the sealing surfaces to eliminate insufficient clearance between the two sealing surfaces. 4. The sealing of elliptical gaskets should ensure that the inner and outer rings of the gasket come into contact, and the two ends of the gasket should not come into contact with the bottom of the groove. 5. The installation of the O-ring should not only meet the design requirements for the ring and groove, but also have an appropriate amount of compression. On the premise of ensuring sealing, the smaller the compression deformation rate, the better, which can extend the service life of the O-ring. 6. Before installing the gasket, the valve should be in the open position to avoid affecting installation and damaging the valve components. When covering, it should be aligned with the position and should not be pushed or pulled into contact with the gasket to avoid displacement and scratches on the gasket. 7. The installation of gaskets for bolted or threaded connections should ensure that the gaskets are in a horizontal position (threaded gaskets with wrench positions should not be used with pipe wrenches). 8. Before tightening the gasket, it is necessary to have a clear understanding of the pressure, temperature, properties of the medium, and material characteristics of the gasket to determine the pre tightening force. The preload should be minimized as much as possible without leakage during pressure testing. 9. After tightening the gasket, it is necessary to ensure that there is a pre tightening gap between the connecting parts in case of gasket leakage. 10. When working at high temperatures, bolts will experience high-temperature creep, stress relaxation, and increased deformation, leading to leakage at the gasket and requiring hot tightening. On the contrary, under low temperature conditions, bolts will shrink and require cold loosening. 11. When liquid sealing gaskets are used for sealin...
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  • What is the Difference Between Gate Valve and Globe Valve?
    What is the Difference Between Gate Valve and Globe Valve? May 31, 2023
    Many people believe that both gate and globe valves have the function of cutting off media, so they are not different when used. In fact, there are certain differences between gate valves and globe valves in practical applications. Gate Valve and Structural Diagram Globe Valve and Structural Diagram 1. Having different structures. Gate valves are more complex in structure, higher in height, and larger in size than globe valves. Gate valves are shorter and higher in appearance than globe valves. Especially, opening the stem gate valve requires a higher height. If the installation position of the valve is limited, it is necessary to choose rising stem and non-rising stem gate valves and remind everyone to pay attention. 2. When fully open, it has different flow resistance. The flow resistance coefficient of ordinary gate valves is approximately 0.08~0.12. The pressure loss during the operation of the gate valve medium is small, and the fluid flow resistance is small. Gate valves are usually suitable for working conditions where frequent opening and closing are not required and the gate is kept fully open or closed. It is not suitable for adjustment and throttling. The resistance coefficient of a regular globe valve is about 3.5-4.5, and the opening and closing forces are very small. The flow resistance of the shut-off valve throughout its entire stroke is very high, and the required driving force or torque is also much greater. But it is very suitable for regulation and throttling. 3. The flow direction of the medium inside the valve body is different. Gate valves have the same effect when viewed from both sides. When installing a shut-off valve, the medium can enter from below and above the valve core. 4. The sealing surface of the gate valve has a certain degree of self-sealing ability. The valve core is in close contact with the sealing surface of the valve seat through medium pressure, achieving sealing performance and no leakage. The sealing surfaces of the shut-off valve only come into contact with each other when fully closed, and the relative sliding amount between the forcibly closed valve core and the sealing surface is very small, so the wear of the sealing surface is also very small. 5. The maintenance procedures are different. The maintenance of gate valves is not applicable to on-site pipelines, but the seat and disc of most globe valves can be replaced online without the need to remove the entire valve from the pipeline (when the valve is not under pressure). This is very suitable for situations where valves and pipelines are welded together. Gate and globe valves are both fully open and fully closed valves. When selecting valves in the application process, attention should be paid to the characteristics of the valves. Globe valves are usually used for small pipelines and better sealing performance. In steam systems and large diameter pipelines, gate valves with low fluid resistance are usually used.
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  • Processing Technology and Structural Characteristics of Triple Eccentric Metal Hard Seal Butterfly Valve
    Processing Technology and Structural Characteristics of Triple Eccentric Metal Hard Seal Butterfly Valve May 24, 2023
    The triple eccentric metal hard seal butterfly valve, as a high-performance valve, has advantages such as corrosion resistance, reliable sealing, and small opening torque. Its sealing surface is an inclined conical surface, and the contact between the valve body sealing ring and the butterfly plate assembly sealing ring is surface contact. Its working principle is to directly drive the butterfly plate assembly by the torque of the driving device, causing the sealing ring of the butterfly plate assembly to fully contact the valve body sealing ring and generate elastic deformation to seal. Structural Characteristics 1. The hard sealed butterfly valve adopts a three eccentric hard sealing structure, with almost no wear on the valve seat and butterfly plate, and has a sealing function that becomes tighter as the valve is closed. 2. The sealing ring is made of stainless steel, which has the dual advantages of metal hard sealing and elastic sealing. Both at low and high temperatures, it has excellent sealing performance, corrosion resistance, and long service life. 3. The sealing surface of the butterfly plate adopts surfacing cobalt based hard alloy, which is wear-resistant and has a long service life. 4. The large-sized butterfly plate adopts a quilted frame structure, with high strength, large flow area, and small flow resistance. 5. According to user requirements, hard sealed butterfly valves can be designed with bidirectional sealing function. During installation, it is not limited by the flow direction of the medium or affected by spatial location, and can be installed in any direction. 6. The drive device can be installed in multiple workstations (rotating 90 ° or 180 °), making it easy for users to use. Processing Technology Based on the structural characteristics of the triple eccentric metal hard seal butterfly valve, the sealing ring of the butterfly plate assembly is a combination of stainless steel plate, asbestos plate, or graphite. The valve body sealing ring is made of hard alloy with high hardness, and it is difficult to control the cutting amount, making it difficult to process and shape in one go. Moreover, the roughness requirements for the machined surface are very high. To ensure processing requirements, the process is as follows: Rough machining of valve body or butterfly plate assembly →→ Valve body sealing ring is welded with hard alloy for insulation and heat treatment to eliminate thermal stress →→ Sealing surface of rough turning of upper tooling →→ Upper tooling precision turning sealing surface →→ Grinding sealing surface with upper grinding head →→ Boring shaft holes for valve body and butterfly plate assembly →→ Strength test sealing test
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