Hydraulic Seal U-Ring Polyurethane Rod Piston Seal Hydraulic Oil Seal U-ring Y-ring X-ring PU NBR FKM material hydraulic oil seal seals
Classification of U-rings
U-ring for shaft, U-ring for hole, U-ring for hole shaft
Scope of application
U-ring is the most commonly used oil seal in hydraulic cylinders, it is a kind of lip seal, whether used for piston or piston rod can obtain good sealing effect. Under low pressure, the U-ring is sealed only by the interference deformation of the lip, and the friction is relatively low due to the small contact area. With the increase of pressure, the amount of elastic deformation of the lip increases, the tensile, compression and bending stress increases, the radial compression of the U-ring automatically becomes larger, and the length of contact with the seal continues to increase until the entire axial length of the U-ring is in contact with the sealing surface, so as to ensure good sealing under high pressure.
When the piston is assembled with U-shaped sealing ring, it is necessary to use a fixture, which is a cone. The diameter of the big head is about greater than the diameter of the end of the piston sealing groove. It is better to have a little bit of the length of the cylinder, and the sharp Angle must be rounded and the roughness must be less than 0.8. The piston and the fixture are installed concentrically, the fixture is coated with butter, the U-ring is heated to 55 degrees in the oil, and then coated with the oil, and pushed along the fixture into the piston seal groove. Guide hole inside the U-shaped sealing ring is more troublesome, first guide sleeve at all the steps of the circular, as long as a little bit of rounded, do not hang hand on the line, and then clean, the inner hole coated with butter, sealing ring is also heated to 55 degrees in oil, and then coated with butter, hand squeezed into the guide hole in the sealing groove, large guide sleeve is better to install, the sealing ring bent into a heart, You can load it.