Alpine Rubber Co.
How to care for your rubber tracks.
Follow these basic measures below to maximize the lifetime of your tracks.
How can we avoid track failure:
When the work is in base metal, rock, sand and mud, you need to allow for the additional packing of material in the inner track rails. When materials pack inside the track rails, over tension occurs and that is when cord tension fails. Track tension of the machine exceeds the track manufacturers design.
Machines without recoilers fitted will damage the track. Machines with recoilers adjusted to give only 10 MM of travel will overstress the track.
The recoiler is the relief valve to track tension overload and if adjusted correctly, will allow stone and or mud packing to revolve around the sprocket with recoil forgiveness. If you remove the recoilers then the track will absorb the load and this will lead to track failures.
What can cause wear?
An undercarriage works as a system. When a machine is in motion, there will be normal, unavoidable wear. With good undercarriage maintenance and operating techniques, the rate of wear can be reduced.
Undercarriage maintenance.
Maintenance practices that can reduce wear are:
1. Track tension or track sag
2. Track width
Correct tension on smaller rubber track machines is about ¾” to 1”.
Correct tension on larger rubber track machines can be as much as 2”.
Track tension and track sag affect wear.
Correct track adjustment is the most important factor to reduce undercarriage wear. Correct track sag for smaller mini excavators need to be adjusted to 1” (+ or _ ¼”). Tight tracks can increase wear up to 50%.
On larger rubber tracked crawlers in the range of 80 horsepower with ½” track sag results in 5,600 pounds of track chain tension when measured at the track adjuster. The same machine with a track sag of 1 inch results in 800 pounds of track chain tension when measured at the track adjuster.
A tight track magnifies the load and puts more wear on the link and sprocket tooth contact. Increased wear also occurs at the track-link to idler contact point and track-link to roller contact points. More load means more wear on the entire undercarriage system.
Also, a tight track requires more horsepower and more fuel to do the job. Follow these steps to adjust track tension:
1. Move the machine forward, slowly.
2. Let the machine roll to a stop.
3. A track link must be centered over the carrier roller.
4. Put a straight edge over the track from the carrier roller to the idler wheel.
5. Measure the sag at the lowest point.
Track width makes a difference.
Select the narrowest tracks possible for your machine. The O.E.M. width track provided for your machine has been chosen because it optimizes that particular machine's performance.
Make sure they give you the floatation you need. Wide tracks used on hard surfaces will put an increased load on the track link system and can affect link retention in the rubber track. A wider than necessary track also increases stress and loads on the idlers, rollers, and sprockets.
The wider the track and the harder the under-track surface, the faster the track treads, links, rollers, idlers, sprockets will wear.
Limit Non-Productive high-speed travel.
Plan your jobsite work carefully to make travel productive. High-speed operation accelerates wear on all undercarriage and track components. Track wear is directly proportional to speed. Speed equals stress. The distance a track machine travels determines wear.
Clean undercarriages frequently.
Preventing packing of soil and debris in undercarriage components by cleaning out the track as frequently as possible. Packing prevents the proper engagement between the mating components such as sprocket teeth and track links. This can increase the load and stress on undercarriage components resulting in higher wear rates.
Limit reverse operation.
Reverse operation accelerates wear on the reverse-drive side of the track links and sprocket teeth. The only time track links rotate against sprocket teeth under load is in reverse operation.
During reverse operation, approximately 75% of track links are under contact, load, and motion, from the bottom of the front idler to the first link engaged by the sprocket tooth. Make reverse travel productive. Forward travel puts about 25% of the track links under contact, load, and motion.
Reduce slippage and spinning.
This accelerates track wear and limits productive work. Heavy contact between the track links and sprocket teeth, between track links and rollers, and idler tread surfaces accelerates wear.
Limit turning if possible.
Plan your job to even out turns if possible. Constantly turning to one side will reduce the life of a track. The sprocket teeth, track links idler, roller flanges, and tread surface on the side under load will wear faster.
Operate with the terrain.
Plan your jobs and the movement of your machines to fit the terrain of your jobsite in order to reduce undercarriage wear.
Working on a crown
Puts all the load and machine weight to the inside track links, inside roller, and idler tread surfaces, and sprocket contact areas. Continual work on a crown will accelerate wear on the inside track contact surfaces.
Working in a depression
Puts all the load and machine weight to the outside-track links, outside roller and idler tread surfaces, and sprocket contact areas. Continual depression work will accelerate wear on the outside contact surfaces.
Working uphill
Shifts the weight of the machine to the rear. This adds more load to the rear rollers and increases sprocket teeth and track link forward drive side wear. There will be a light load on the undercarriage when reversing down the hill.
Working downhill
Shifts weight to the front of the machine. The additional load will be placed on the front roller, idler tread surface, and track links. When you reverse up the hill, the link rotates against the reverse-drive side of the sprocket tooth. Also, there is a heavy load and motion between the link and the sprocket teeth, which accelerate wear. A heavy load is placed on all links from the bottom of the front idler to the first link contacted by the sprocket teeth. Extra load is also placed between the sprocket teeth and the track links and the idler tread surface. The life of the links, sprockets, rollers, and idlers is reduced.
Working on a slope or side hill
Shifts weight to the downhill side of the machine and causes additional wear on the roller flanges, sides of the track links, and tread tread. Balance wear between each side of the undercarriage by changing the work direction on the slope.
Alignment checks:
Track frame and front idler misalignment will accelerate wear on all components. Check for track alignment by observing the wear patterns on the bottom rollers, carrier rollers, and front idlers. A visual inspection can also be done by just standing at the front and rear of the machine. See your machine manuals for specific adjustment procedures.