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Based on industry information, incorrect tensioning of tracks leads to premature wear of track rollers, idlers, and drive sprockets by as much as 50%; additionally, it causes increased fuel consumption and heat buildup that may be damaging to the machinery. Typically, for a crawler crane, proper tensioning produces about 800 pounds of tension; however, an over-tensioned track could produce tension of as much as 5,600 pounds, thus placing extra stress on components and increasing energy requirements.

The Basics of Crawler Crane Track Tension Adjustment

Track sag, which is described as the vertical gap between the track rollers and track links, is used as the main criterion for determining correct track tension.

Tracks that are loose could cause derailment, particularly during turns or inclining movements, leading to damages of undercarriage frame, track rollers, idlers, drive sprockets, and tracks themselves. Excessive track tension increases the load placed on all crane undercarriage parts and increases wear and tear.

Standard Measurement Procedures

Steel Crawler Track Measurement

For conventional steel crawler crane tracks, industry-standard procedures require:

1. Position the machine on level, solid ground 
2. Raise the tracks using the boom and bucket or outriggers until the tracks clear the ground 
3. Clean the undercarriage thoroughly before measuring, as accumulated debris affects readings 
4. Rotate the tracks backward two full rotations, then forward two full rotations 
5. Measure the sag at the middle of the track frame from the bottom of the frame to the back face of the track shoe 
6. Standard steel track sag specifications vary by machine size:
7. Larger crawler cranes (Manitowoc spec): 70–80 mm minimum sag 
8. Reference for Other Models: Specifications for certain older or smaller devices may differ; please refer to the specific operation manual

Adjust Crane Track Tension  Measurement

The Grease Cylinder Adjustment Method

Most modern crawler cranes utilize a spring tensioning fixture or grease cylinder located behind the front idler to adjust track tension. The system operates by pumping grease into the cylinder, which expands and pushes the idler forward, tightening the track.

Tightening the Track

1. Position the machine on level ground 
2. Remove the access cover protecting the grease valve 
3. Connect a grease gun to the lubricating valve 
4. Inject grease slowly and intermittently, checking sag frequently 
5. Replace the cover and repeat on the opposite track 

Critical safety note: Grease in the tensioning cylinder is under extreme pressure. Never completely remove the valve or lubricating nipple, as escaping grease can cause serious injury. Always use an extension hose to maintain a safe distance.

Loosening the Track

When track tension is excessive:

1. Locate the grease valve on the tensioning cylinder 
2. Using a socket wrench, slowly rotate the valve counterclockwise for 1–1.5 turns 
3. Allow grease to escape through the vent opening—the track will gradually loosen 
4. If grease does not discharge smoothly, lift the track off the ground and rotate slowly to relieve pressure 
5. Once the sag reaches specifications, tighten the valve clockwise 

Environmental Conditions

Temperature changes have a major influence on track tension. Tracks that are well-tensioned in the morning under cool temperature conditions can become overly slack as a result of increasing temperature and heating up of the tracks.

The condition of the surface is also important. There are recommendations to perform tests in the field instead of performing them inside the workshop, since tracks correctly tensioned indoors might be too tight in muddy operating conditions.

If there is debris accumulated between rollers and tracks due to excessive slackness of the latter, this can cause significant component damage.