German VEM seals VEM models VEM prices

VEM seals utilize the "container" concept from transportation to create cartridge seals. The rotating and stationary parts of this seal are pre-assembled into a single unit before installation. After passing inspection and pressure testing, the unit is mounted on the shaft within the stuffing box, fixed to the shaft with set screws, the gland bolts are tightened, and the cartridge positioning tabs are removed, allowing the mechanical seal to operate in a parallel face condition and be put into service. This approach not only simplifies assembly but also ensures assembly quality. Welded metal bellows mechanical seals are all designed as cartridge seals, offering the aforementioned advantages. Cartridge seals are also a type of cartridge mechanical seal. In this seal, the stationary ring, rotating ring, sleeve, gland, and auxiliary seals are all assembled together on a single sleeve before installation, facilitating inspection of assembly quality. Once inspection is passed, it is only necessary to tighten the seal cover and secure the screws. This pre-assembled, inspected, and tested seal component makes it easy to ensure installation and assembly quality.

VEM seal types

1) Squeeze-type seals: Squeeze-type seals, particularly O rings, have been widely used in sealing applications. Other types such as X type, T type, D type, square, and triangular shapes are suitable for different applications. Improvements aim to stabilize and reliable seal performance, increase pressure resistance, and reduce friction. They can also form combination seals with low-friction plastics such as PTFE and nylon slide rings and support rings to increase pressure resistance and reduce friction. Some manufacturers' products are permitted to reach speeds of 7.5m/s and sealing pressures of 5.6MPa. 2) Reciprocating lip seals: Reciprocating lip seals, also known as lip gaskets or cups, are widely used for dynamic sealing in hydraulic system reciprocating cylinders. The pressure-bearing surface of this seal is lip-shaped, with a minimal interference fit during installation, ensuring full contact between the lip edge and the sealing surface to create a seal. When the cylinder operates, as pressure increases, the contact force and contact area increase, thereby improving sealing. During the cylinder return stroke, pressure decreases, and both contact area and friction are lower than during the working stroke, creating a breathing effect that lubricates the lip. There are many types of reciprocating dynamic seals, commonly including J type, L type, U type, V type, and Y type. There are also various combination and composite seals, such as U-cup, V-ring, and multi-lip seals. Extrusion must be prevented under high pressure by selecting materials with sufficient tear strength, hardness, and modulus, or by using support rings for protection, or by employing reinforced elastomers. Seals used under high pressure, high speed, or high temperature often use composite combination seals. Their common feature is having two lips in contact with the cylinder wall. A groove in the middle of the sealing area can store media, improving lubrication, reducing lip wear, and ensuring reliable sealing. Lip seals used in pneumatic systems are required to operate without oil lubrication; contact pressure varies, and some designs integrate a dust wiper with the seal. 3) Rotary shaft lip seals: There are no fewer than 200 varieties of similar structures, such as hydrodynamic type, inner caged, assembled, outer caged, bonded PTFE AF type, dual-durometer return flow type, etc. The advantage of the outer caged assembled type is accurate positioning, high concentricity, and good heat dissipation conditions. It remains stable under pressure and vibration, resulting in a longer service life while saving rubber material. The dual-durometer return flow type applies wave seal theory; by adding a low-modulus, easily deformable material at the sealing contact point, a return flow effect is achieved, simultaneously reducing product design and mold processing costs. Joints between rigid waterproof layers and gable walls, parapet walls, and protruding roof structures should be properly treated with flexible sealing.

VEM seal influencing factors

Hydraulic seals play a crucial role in the integrity of hydraulic and pneumatic systems. If the seals on a hydraulic or pneumatic component are substandard, the component itself cannot be considered a good product. Many factors influence seal performance. First, pressure is a significant factor affecting seal quality; the magnitude of pressure and the duration of pressure cycles greatly impact seal damage (such as extrusion). The higher the pressure, the greater the influence of other factors on seal performance, such as temperature, speed, seal material, the gap between the piston and cylinder barrel, and the gap between the piston and cylinder head. Another factor is temperature and friction. Describing the maximum and minimum operating temperatures for a seal material is difficult because it is the result of a combination of factors. Operating temperatures for pistons and piston rods differ, requiring distinct selections. Additionally, seal surface roughness, surface characteristics, pressure, media, temperature, seal material, seal type, and motion speed are all factors affecting seals. Finally, surface treatment is critical; experience shows that the surface characteristics of cylinder pistons and piston rods significantly impact seal life. Surface characteristics are often defined by the RA value, where RA is the arithmetic mean of the absolute values of surface profile deviations from the centerline. However, these values do not fully represent the impact of surface conditions on seals, because even at the same roughness, different surface shape characteristics can lead to varying degrees of seal wear.

VEM seal functions and applications

Engine: Crankshaft - front and rear crankshaft oil seals; Valve - valve stem seals (engine repair kit o rings) (distributor oil seal, water pump oil seal, balance shaft oil seal, oil pump oil seal...); Camshaft - camshaft oil seal; Transmission: Transmission - front and rear transmission oil seals; shift lever oil seal (transmission repair kit o rings) (transfer case - front and rear transfer case oil seals); Rear Axle: Half-shaft - rear half-shaft oil seal; Differential - (front/rear) pinion oil seal; rear wheel oil seal; front wheel oil seal; steering gear oil seal (steering gear repair kit o rings); power steering booster oil seal (front half-shaft oil seal). Oil seals are required wherever a rotating housing contains liquid lubricant and connects to the exterior. Some are made of rubber, some of metal, but most are steel-cased rubber, such as rear crankshaft oil seals, front and rear transmission oil seals, left and right half-shaft oil seals, final drive front oil seals, and air compressor crankshaft oil seals.

Weidou Intelligent Technology specializes in selling German VEM seals, VEM O-rings, VEM sealing strips, VEM pipe seals, VEM cable seals, VEM rubber seals, VEM mechanical seals, VEM gaskets, VEM oil seals, VEM shaft seals, VEM metal seals, VEM high-pressure seals, VEM spiral seals, VEM centrifugal seals, VEM sealing rings, VEM original German imports. We welcome customer inquiries and orders.