Hydraulic seals manufacturer and supplier from dmsseals.com: The Fluid Film – In most mechanical seals the faces are kept lubricated by maintaining a thin film of fluid between the seal faces. This film can either come from the process fluid being pumped or from an external source. The need for a fluid film between the faces presents a design challenge – allowing sufficient lubricant to flow between the seal faces without the seal leaking an unacceptable amount of process fluid, or allowing contaminants in between the faces that could damage the seal itself. This is achieved by maintaining a precise gap between the faces that is large enough to allow in a small amounts of clean lubricating liquid but small enough to prevent contaminants from entering the gap between the seal faces. This micro-gap is maintained using springs and hydraulic force to push the seal faces together, while the pressure of the liquid between the faces (the fluid film) acts to push them apart. Find extra info on rod seals.
What are Mechanical Seals? Mechanical seals are devices that accommodate a rotating shaft while containing and preventing the fluid from leaking out of the enclosed housing. While different mechanical seal designs are available for pumping applications, most have three sealing points. Rotating face that rotates with the shaft; Stationary face fitted to the pump housing; Interface portion between the rotating and stationary face of the seal. These three sealing points ensure that the fluid contained within the pump housing does not leak while also preventing dust particles in the atmosphere from entering the housing. The mechanical seals are usually made up of different materials to prevent sticking. Typically, one side of the seal uses softer materials like carbon graphite, and the other is made of harder materials such as silicon carbide or ceramic alumina. However, hard materials are preferred for both surfaces if the pumping application involves abrasive fluids. In addition to the two materials, the sealing unit also comes with O-rings to seal the stationary face on the housing side and the rotating face on the shaft side. Springs are also used to keep both faces pressed. In most cases, the two faces of the seals are also lubricated to prevent friction and wear. Depending on the application, this fluid film can either be a separate lubricant or the process fluid itself.
Due to the volume and weight limitations of the system, it is impossible to install an ideal filtration and cooling system. High temperature, high pressure, and high speed cause the hydraulic oil to deteriorate easily, and the mechanical parts are also prone to erosion and stains. There are many stains and impurities in hydraulic oil, but it cannot be thoroughly filtered, which is the aspect of endogenous stains. All kinds of dust in the working environment may be very large, and it will inevitably enter the hydraulic system in multiple ways, causing oil pollution, which is an external stain. Therefore, the sealing system is required to be resistant to stains.
It is ideal for single-acting sealing of reciprocating piston rods or pistons with a wide operating pressure range of up to 20 MPa. The operating temperature range is also wide from -200°C to + 250°C. It has a diameters range from 3 mm to 1600 mm and a working speed of 5 m/s. The seal has a low coefficient of friction and the friction between the contact faces is minimal among all seal types. Moreover, the contact pressure between the mating surfaces is low. It can work without lubrication and is very wear resistant. And it has a long service life.
It adopts the most ideal design and improved sealing performance and can minimize the high strength of local stress. This type of seal is designed to simplify installation and reduce particle generation. Moreover, it can be quickly and easily installed and removed to facilitate hardware assembly. It perfectly combines a custom seal design, proprietary bonding technology, and excellent plasma resistance developed for semiconductor applications. And its unique structure can minimize common installation problems.
Since the scraper seal is made of the special material, PTFE, it has an impurity immersion function. Therefore, when combined with the piston rod seal and the metal bushing, it can prevent damage to the piston rod and prevent the accumulation of oil pressure. It has a diameter range of 3-1600mm and a temperature range of -30°C + 200°C. The wiper scraper seal can operate at speeds of up to 5 m/s. It has high wear resistance, tear resistance, low-temperature resistance and good strength. Our wiper seals can be used in combination with piston seals and anti-wear rings to prevent oil in the cylinder from being mixed with foreign matter, which causes damage to the working seal. It is especially suitable for piston rods with a large diameter. Moreover, it has a wide range of applications, such as agricultural machinery, injection moulding machines, forklifts, cranes and so on.
Diffusion leakage: Driven by the concentration difference, the medium leaks through the material transfer generated by the sealing gap or the capillary of the sealing material. Diffusion is the result of molecular motion and is not unidirectional. When the sealing pressure difference is extremely small or in a vacuum state, or when sealing permeable substances such as nitrogen and hydrogen, as well as highly toxic and radioactive substances, special attention should be paid to the leakage and diffusion.
We own a number of invention patents and leading production process. The R&D teams have the ability to design and develop seals for various of complicated working condition of sealing system. We have already passed the certification of ISO 9001 and IATF 16949. We have the mature technical reserve for the solution of ultra-high temperature, ultra-high pressure, ultra-low temperature, highly corrosive and other special working condition. Read extra details on https://www.dmsseals.com/.
DMS Custom Rubber Rings, O Ring Company & factory covers an area of more than 10,000 square meters and the factory area is 8,000 square meters. Our production equipment and test equipment are at the leading level in the industry. We are one of the largest companies in China specializing in the production and development of seals. We have long-term communication and cooperation with many universities and research institutions at home and abroad.