SHOE WEAR AND BREAKAGE

When wear is even over the entire grouser surface of the shoe, it is considered “normal”.

Causes of occurrence

Sliding ground contact.

Factors accelerating wear

Any factors that increase the ground contact force and thereby cause abrasion of the shoe's grouser will contribute to wear. These factors include the following: machine weight, power, travel speed, ground pressure, abrasiveness of the ground, terrain, as well as factors that arise during the operation of the machine and cause inefficient turns and slip.

Produced effect

• Reduced traction
• Bending
• Reducing possibility of grouser repairing as its service life expires.

Prevention and elimination

• Elimination or minimization of the influence of controllable factors on the undercarriage.
• Use of reinforced shoes if conventional shoes have to be changed before link wear or repair with bushings and pins overturned.

The grouser ends wear faster than the center of the grousers.

Causes of occurrence

Same as for even wear, but ground conditions and factors that accelerate wear play a critical role.

Factors accelerating wear

High ground pressure can be detrimental to grousers angles, especially when wide shoes are used at constant, sharp turns during machine operation.

Produced effect

Shorter grousers life and reduced traction.

Prevention and elimination

Use the smallest possible shoe width and eliminate or minimize the influence of controlled factors on the undercarriage.

Bending and wear of the shoe flange, including front and rear edges.

Causes of occurrence

The main reasons are the same as for uniform wear.

Factors accelerating wear

• Rapid wear of shoes in case of intensive use.
• High abrasiveness of the soil and rock particles penetrating into the overlapping area of the upper and lower edges of the shoe will lead to faster wear of these parts of the shoe.
• The top and bottom edges of the shoe are also affected by the internal pivot wear.

Produced effect

• Lack of ground contact and inability to restoregrousers.
• Risk of breakage.

Prevention and elimination

• Same as for uniform grousers wear.
• Use the smallest possible shoe width and eliminate or minimize the influence of controlled factors on the undercarriage.
• Install a track chain with seals and liquid pivot lubrication if wear on the top and bottom edges of the shoe has a significant impact.

Causes of occurrence

When the load on the shoes due to the applied pressure is greater than the resistance of the materials, it can lead to cracks and breakages.

Factors accelerating wear

In addition to typical catalysts, the most important factor in controlling shoe resistance is shoe width.

Prevention and elimination

• Reduced shoe life.
• Cost of shoe replacing.

Remedies

The best solution is to choose the narrowest shoes possible, which would provide normal flotation. It is necessary to use reinforced shoes in case of heavy work.

Breaking holes for shoe bolts.

Causes of occurrence

• insufficient tightening torque when installing shoes;
• insufficiently even mating surfaces of the link and shoe;
• bolt stretching due to insufficient strength class and excessive loads exceeding its yield strength, high loads when working on rocky ground.

Factors accelerating wear

• Extra wide shoes
• Exceeding the required bolt tightening torque when installing the shoes.

Produced effect

• Broken shoe bolts and shoes
• Reducing the service life of the shoes
• Loss of ability to use shoes after grouser restoration
• Possible damage to the bolt holes in the chain links.

Prevention and elimination

• Select shoes as narrow as possible to ensure adequate flotation. When using wide shoes, use shoes with cuts at the ends of the grousers to reduce loads at machine turning.
• Use reinforced shoes if normal shoes are bent.
• Always use the correct bolt torque and follow bolt tightening instructions.
• Be sure to remove paint, dust and rust from the mating surfaces of the chain links and shoes when installing them.
• Use new shoe bolts and nuts when installing new shoes on the track chain.
• Periodically (at least once a week) check the tightening torque (tighten with the required torque) of the shoe bolts