Undercarriage track wear

To determine whether wear on the undercarriage track chain warrants an undercarriage overhaul, we provide some tips below to help you make an assessment. A visual inspection of the undercarriage can quickly reveal a great deal about the degree of wear and the condition of an excavator's tracks chains.

Bushings

First and foremost, examine the chains bushings. Friction against the sprocket teeth causes the diameter of the chain bushings to decrease. Naturally, the bushings do not wear evenly all the way around; in excavator chains, only the side of the bushing facing the sprockets experiences a reduction in wall thickness. Over time, the wall thickness decreases to such an extent that, under the influence of various forces and loads, small cracks develop in the bushings. At a more advanced stage, the wear becomes so severe that formation of holes occurs on the bushings.

Slijtage aan de ketting van het rijwerk onder de vorm van barsten in de bussen

In other words: if you notice cracks or holes in the bushings, one can consider the track chains as completely worn out, and this may result in replacing the track chain.

Front idler position

The position of the front idler can also reveal a great deal about the wear on the undercarriage track chain: as a track wears, it elongates. Since the aim is to maintain a certain level of tension on the tracks, the track requires periodic retensioning. By pumping grease into the tensioner, the front idler is pushed forward to tighten the track. Over time, you may notice the front idler's brackets (slides) gradually sliding out of the frame (chassis). The appearance of these brackets does not necessarily mean the track is 100% worn out, but it likely indicates wear of 75% or more.

bij een nieuw rijwerk is het voorwiel van de graafmachine helemaal ingeschoven.

Bij een graafmachine met versleten rijwerk steekt het voorwiel uit het chassis.

Bottom roller flanges

Another wear pattern that can be identified during a visual inspection is the extent to which the flanges of the bottom rollers come into contact with the track chain pins.

Flensen van een versleten onderrol raken de pinnen van de ketting.

On one hand, as the bottom roller wears, the diameter of its running surface decreases. On the other hand, as the chain wears, the height of the links is reduced. Consequently, the flanges come into contact with the reinforcement around the pins. With this pattern of wear, it becomes necessary to replace either the track chains or the bottom rollers, or both.

Loose pins

slijtage aan de ketting van het rijwerk waarbij de pinnen los zitten.

In certain cases, wear on the track pins and track bushings is minimal, yet another issue may necessitate replacing the chains. This sometimes happens when pins begin to develop play within their links. If pins start to shift, it is a clear sign that the chain's reliability and service life are being compromised.

If this occurs in just one link, the chain can be restored by replacing that specific link. However, if it affects multiple links, the only option is to replace the track chain entirely.

Questions?

If you have any further questions regarding wear on the undercarriage track chain, please contact us today at +3292510796, via [email protected], or through the contact page.

Click the following links if you would like to know more about:

Wear on undercarriage sprockets.
Wear on undercarriage rollers.
Wear on excavator track shoes.
Wear on undercarriage front idlers.
Wear on chain guides.