Installing sealing rings prevents oil leaks in the excavator's hydraulic cylinders, but several issues need attention during installation.
1. Before installation, inspect the quality of the sealing ring, especially the lip area, ensuring there are no damages or defects. After checking the quality, verify that the sealing ring's dimensions match the cylinder's dimensions.
2. When installing the lip seal, for example, at the end of the cylinder barrel and piston rod, chamfer the edges at a 15 to 30-degree angle to prevent damage to the lip during installation.
3. If the lip seal needs to pass over a relief groove or threaded surface during installation, use a sleeve over the area. Alternatively, design the threads and relief grooves with a diameter smaller than the inner diameter of the lip seal. When passing over threaded surfaces and bore openings, ensure the inner diameter of the passage is larger than the outer diameter of the lip seal.
4. To reduce assembly resistance, apply lubricating oil to the lip seal and the installation area during installation.
5. Minimize excessive stretching during installation to avoid plastic deformation. If the ambient temperature is low, the lip seal can be heated in hot oil at approximately 60℃, but the temperature should not exceed the lip seal's operating temperature.
6. If the working pressure exceeds 20 MPa, in addition to using a composite lip seal, a backup ring should be added to prevent the lip seal from being squeezed out. The backup ring is installed next to the base of the lip seal. When installing the lip seal into the cylinder barrel, to prevent the beveled edge of the backup ring from being cut, apply lubricating oil to the beveled edge to secure it in place before installation.
