What is a V-Seal?
V-Seal, as its name describes, has a "V"-shaped cross-section.
The V-seal is characterized by low working resistance, smooth operation, and high resistance to pressure, vibration, and impact. It can accommodate different media and operating conditions. Multiple intermediate rings can be added and used in combination, allowing the compression force to be adjusted for an optimal seal. However, its drawbacks include high friction resistance and a complex structure. It requires pressure and support rings, and its sealing performance can be unstable. This seal type is commonly used for dynamic sealing in reciprocating pistons or piston rods and can also be used in some rotary or static applications.
As mentioned, a V-Seal assembly consists of three parts: a middle V-ring, and upper and lower support rings with a compression ring. The number of V-rings can be customized to requirements, such as 3, 5, or 7 pieces.
Why use V-Seals in mechanical parts?
V-seals are a widely used type of lip seal with a long history of technical development. Compared to common lip seals, their main features are:
Customizable Pressure Handling: The number of rings can be selected based on the working conditions and required pressure capacity. The sealing performance improves with more intermediate rings, though this relationship is not linear. It is important to note that increasing the number of rings also increases friction resistance.
Strong Dynamic Sealing: They provide excellent dynamic sealing with high load capacity and superior leak prevention.
Adjustability and Long Life: If a leak occurs due to seal deformation or wear, the clamping mechanism can be adjusted and tightened to increase the lip contact angle, restoring the seal. This makes the V-seal group reliable and long-lasting.
Easy Maintenance: The number of intermediate rings can be easily increased or decreased based on actual needs. The assembly is easy to maintain, making it suitable for replacing seals in hard-to-reach locations.
Versatility: They can be used under low-pressure (5MPa) and low-speed (3m/min) rotation conditions.
Anti-Extrusion Performance: They offer excellent resistance to extrusion under both high and low-pressure conditions.
The V-seal ring is named for its V-shaped cross-section, similar to how an O-ring is named for its O-shape. It is a type of lip seal.
A V-seal assembly generally consists of three parts: a support ring, a seal ring, and a pressure ring. In some applications, the standard 90-degree V-seal ring angle may be 60 degrees. The support ring is a crucial component that supports the V-seal ring. It has a thick, sturdy cross-section, precise dimensions, and a concave angle that matches (90 degrees) or is slightly larger than the V-seal ring, ensuring a stable fit.