​​​​​​​Solutions to Leakage of Rotating Rubber Oil Seals

Solutions to Leakage of Rotating Rubber Oil Seals

Rotating rubber oil seals are essential components in various machinery, ensuring that fluids, such as oils or lubricants, do not leak from the sealed system. However, during operation, leakage can often occur at localized points due to various issues. Identifying the root cause of the leakage is crucial to resolving the problem and restoring the seal's functionality. Below are common causes of leakage in rotating oil seals and their corresponding solutions.

1. Causes and Solutions During the Friction Process

Excessive Pressure:
When the internal pressure in the system exceeds the designed limit, the oil seal may fail to maintain an effective seal, leading to leakage.
Solution:

• Replace the existing oil seal with one designed to handle higher pressures.
• Ensure the operating pressure of the system aligns with the specifications of the sealing components.

Excessive Pre-tightening Force:
If the pre-tightening force applied during installation is too high, it can deform the oil seal, leading to leakage.
Solution:

• Adjust the pre-tightening force to the recommended level to avoid over-compression of the seal.
• Consider changing the sealing method or design to reduce the required pre-tightening force.

Lubrication Problems:
Inadequate lubrication or using the wrong type of lubrication can increase friction between the sealing surface and the shaft, causing wear and leakage.
Solution:

• Replace the friction surface material with PTFE (Polytetrafluoroethylene) or another low-friction material that provides better lubrication and reduces wear.
• Ensure proper lubrication is used and that it’s compatible with the oil seal material.

2. Causes and Solutions for Oil Seal Damage

Shaft Roughness:
The roughness of the shaft surface can damage the oil seal and result in leakage. Irregularities like bumps, grooves, or excessive surface roughness may cause premature wear on the seal lip.
Solution:

• Maintain strict control over the shaft surface roughness, ensuring it meets the necessary specifications for smooth contact with the sealing lip.
• Pay attention to the chamfering process, ensuring edges are properly finished to prevent the seal from being damaged during installation.

Improper Installation:
Incorrect installation of the oil seal, such as misalignment or improper sealing technique, can cause leakage.
Solution:

• Use appropriate sealing installation tools to ensure proper alignment and correct installation.
• Follow proper installation procedures and techniques to ensure the seal is fitted correctly.

Wear Particles:
When oil seals are exposed to dusty or abrasive environments, wear particles can build up and damage the sealing surface, leading to leakage.
Solution:

• Use a dust-proof oil seal in environments where dust or other abrasive particles are present to prevent contamination and damage to the seal.
• Regularly clean the sealing area and the surrounding environment to minimize particle accumulation.

3. Additional Reasons and Solutions for Oil Seal Leakage

Damage and Surface Wear of the Rubber Oil Seal:
Over time, rubber oil seals may experience damage or surface wear, especially if the seal was not made from durable materials.
Solution:

• Choose oil seals with better resistance to rotational wear and made from high-quality materials that offer improved durability.
• Ensure that the rubber material is appropriate for the working conditions (e.g., temperature, pressure).

Cracked Lip of the Rubber Oil Seal:
A cracked seal lip may be caused by rough shaft surfaces, inappropriate sealing materials, or excessive speed and temperature fluctuations.
Solution:

• Inspect the shaft surface for any irregularities or damage.
• Use sealing materials suitable for the specific operating temperature and conditions.
• Ensure the seal is designed to handle the operating speed of the machinery.

Inadequate Lip Pressure of the Rubber Oil Seal:
If the lip pressure of the seal is insufficient, it may not provide an effective seal, leading to leakage.
Solution:

• Check if the size of the oil seal matches the shaft size and confirm that it’s properly seated.
• Verify that the internal spring of the oil seal is functioning correctly and providing adequate pressure against the sealing lip.
• If necessary, replace the oil seal with one that offers better lip pressure.

Improper Assembly of the Oil Seal:
Incorrect assembly, such as installing the oil seal in the wrong orientation or displacement, can prevent it from sealing properly, causing leakage.
Solution:

• Ensure the oil seal is installed correctly, with the correct orientation (e.g., the spring side facing the correct direction).
• Avoid displacing the seal during installation, which could lead to gaps or improper sealing.