Analysis of Track Roller Oil Leakage and Maintenance Methods

The track roller is a critical component of any crawler-type construction machine. It bears the full weight of the equipment and often works in harsh environments such as gravel, mud, and water. To ensure proper operation, the track roller must maintain excellent sealing performance. During winter, low temperatures make oil-leak issues even more common, which can affect the machine’s overall performance and job progress.
Therefore, understanding the causes of oil leakage and applying targeted maintenance is especially important.

01 Working Principle of the Track Roller

When the track roller is in operation, the end caps—together with the floating seal rubber rings, floating seal rings, the shaft, and the O-rings—remain fixed to the machine frame. Meanwhile, the roller body and the bimetal bushings (along with the floating seal rings and rubber rings on both ends) rotate around the shaft.

To reduce friction and wear, a specific amount of lubricant is added to the roller cavity through the oil-filling port during assembly. The port is then sealed with an oil plug.

02 Analysis of Oil Leakage in Track Rollers

During operation, various factors may cause lubricant inside the roller to leak. The main reasons include:

A. Poor dimensional accuracy or surface roughness of the shaft, bushing, or end cap.
This can lead to abnormal wear between these components. As metal powder accumulates inside the roller, it contaminates the lubricant. Once these particles enter the floating seal surface, they accelerate wear and cause seal failure.

B. Insufficient structural strength of the roller body or end cap.
Deformation of the floating-seal chamber during operation may twist or misalign the seal assembly, resulting in leakage.

C. Incorrect lubricant selection.
If the oil cannot perform under local temperature conditions, an effective oil film cannot form. This leads to abnormal wear, increased heat, and eventual seal failure.

D. Machine frame or other components not level.
Uneven loading causes excessive wear on the seal assembly, shortening its lifespan and leading to failure.

To address these common market issues, Jingqing’s crawler undercarriage system has undergone targeted improvements. Components are assembled in a professional dust-free cleanroom to ensure cleanliness and prevent contaminants from entering sealing surfaces. In addition, the structural design has been optimized and upgraded sealing materials with a wider temperature range have been adopted. These improvements significantly enhance roller reliability and durability, reducing oil-leak incidents.

03 Maintenance Methods for Track Rollers

In addition to design improvements, regular maintenance is necessary during machine operation. Recommended maintenance practices include:

A. When working in harsh environments, avoid prolonged submersion of the track rollers in muddy water.
At the end of each workday, lift one side of the track and use the travel motor to spin off mud, rocks, and other debris.

B. Remove the oil plug and add a small amount of lubricant (commonly the same gear oil used in travel or swing reducers—consult the manufacturer for special working conditions).
This should be done every 6 to 12 months.

C. In low-temperature environments, keep the rollers dry.
Because track rollers use floating seals between the outer roller and the shaft, water entering the seal cavity may freeze, locking the seal in place. This causes the rubber ring to lose elasticity, compromising the seal and eventually causing oil leakage.