Track Talk
One of the most common mistakes construction companies make is assuming that one track fits all applications. That is not the case, and there is a perfect track for each need. Whether you’re working in hard and rocky conditions or on spongy clay and top soil, here are some pointers to make sure you’ve selected the right track for optimal operation in your conditions.
Ground Conditions Drive Decisions
Steel tracks are the most commonly used, and there are two primary considerations: track width and the total number of grousers. Each plays an important role in flotation and performance.
A narrow track is ideal for hard soil and rocky ground conditions because it provides excellent grip and bite — and minimizes the potential for deflection that can occur with wider tracks. Deflection occurs when the shoe rolls over an obstruction, such as a large rock or stump, and the weight of the machine is unevenly distributed over to one side of the shoe. As the shoe rolls over the obstruction, for example, there’s a concentrated weight load causing increased potential for the shoe to bend and crack.
A wide track is ideal for bearing the weight of the excavator over a larger surface area to achieve lower ground pressure. A wider track provides better flotation when working in soft or wet soil conditions and often causes less disturbance to the existing ground.
Rubber tracks and bolt-on rubber pads are also a good option when working in soft conditions and traversing ground where the potential for damage to the ground must be minimized. Rubber tracks are generally used on excavators with operating weights less than 13 metric tons.
The Art of the Grouser
Most manufacturers offer track shoes with triple grousers but single and double grousers are available. A grouser is the raised protrusion (or bar) that runs the width of the shoe surface. Also called grouser shoes, they increase traction to meet all soil conditions.
Triple-bar grouser shoes are used when low ground pressure, greater flotation and greater maneuverability are needed. Conversely, a single grouser shoe is typically a better choice for gravel or rocky conditions where greater bite into the operating surface is required.
Best Practices to Boost Track Longevity
A number of best practices will help keep excavator tracks in good working condition. They include:
Proper track tension: Check it daily to match jobsite conditions. If it’s too loose or too tight, it results in excessive wear. It will also cause stress on the undercarriage and drivetrain components. It is also important to tension the tracks specific to the soil you are in, as each soil type will affect tension differently.
Wash-down and walk-around: In addition to a general wash-down at the end of the day, operators should always clean out mud and debris from the undercarriage. Another essential operator requirement is to inspect the undercarriage and report any damage or uneven or excessive wear — in addition to missing components. Unaddressed instances of uneven wear will eventually cause the tracks to overcompensate for the worn component and cause wear in other parts. Inspect the track for any oil leakage. Signs of oil could indicate a damaged seal.
Routine maintenance: Besides the daily inspection and track tensioning, it is required to replace the travel reduction gear oil per manufacturers’ recommendations. Periodic tensioning of track shoe bolts is required.
Operator training: Ongoing training will contribute to track longevity. Operators must understand best practices when operating a tracked excavator, such as avoiding unnecessary operation in reverse; avoid 360 degree turns, and slower track movement is always preferable. Long and deliberate movements are particularly necessary with rubber tracks and rubber pads as these will easily get torn up if operated improperly.
The Best Choice Is Thinking It Through
Whether it’s digging, trenching, moving pipe or any other task, users make the best decision when thinking through excavator track options long before arriving on the jobsite. And given the many track shoe options available and other issues involved, never hesitate to reach out to your local heavy equipment dealer with questions when in doubt.
Dave Wolf is a Customer Support Manager for Case Construction Equipment.