Track rollers and carrier rollers are both part of an excavator undercarriage, but they are installed in different positions and perform different jobs.
Track roller
The track roller is installed along the lower track frame. It supports the machine weight and guides the track chain as the excavator travels. A machine normally uses several track rollers on each side.
Track rollers may differ in body width, flange arrangement, shaft structure, mounting-hole spacing and installation height. Heavy-duty or mining machines may use different structures from standard construction excavators.
Carrier roller
The carrier roller is installed on the upper part of the track frame. It supports the returning track chain and helps prevent excessive sagging or contact with the track frame. A machine typically uses fewer carrier rollers than track rollers.
Carrier rollers vary in roller diameter, bracket style, shaft type and mounting dimensions. A carrier roller that looks similar may still not fit another model.
Why the machine model may not be enough
Different serial-number ranges, track-frame configurations and regional specifications can affect the correct roller. The safest confirmation combines the full machine model with a part number, old-part photo or mounting dimensions.
Information to provide
- Excavator brand and full model
- Machine serial number
- Part number if readable
- Photos of the old roller and mounting position
- Mounting-hole spacing and key dimensions
- Required quantity
Other undercarriage parts
A complete undercarriage request may also include idlers, sprockets, track chains, track-link assemblies, track shoes and track adjusters. Supplying the full machine information helps keep the parts consistent within the same order.