Track loader

A track loader is an engineering vehicle consisting of a tracked chassis with a loader for digging and loading material. The history of track loaders can be defined by three evolutions of their design. Each of these evolutions made the track loader a more viable and versatile tool in the excavation industry. These machines are capable in nearly every task, but master of none. A dozer, excavator, or wheel loader will out perform a track loader under a set of conditions, but the ability of a track loader perform almost every task on a job site is why it remains a part of many company's fleets.

The first track loaders were built from track tractors with scratch built loaders. The first loaders were cable operated like the bulldozers of the era. These track loaders lacked the ability to dig in hard ground, but so did the dozers of the day. They were mostly used for moving stockpiled material and loading trucks and rail cars.

The first major design change to track loader came with the integration of hydraulic systems. Using hydraulics to power the loader linkages increased the power of the loader. More importantly, the loaders could apply downpressure to the bucket, vastly increasing their ability to dig unworked ground. Most of the track loaders were still based on a bulldozer equivalent. The weight of the engine was still on the front half of the tracks along with the heavy loader components. This caused many problems with heavy wear of the front idler wheels and the undercarriage in general. The Caterpillar 983 track loader, the second largest track loader ever built, was notorious for heavy undercarriage wear.

The hydrostatic drive system was the second major innovation to affect the the design of track loaders.

Track loaders have become very sophisticated machines, using hydrostatic transmissions and electro-hydraulic controls to increase efficiency. Until the rise in popularity of excavators, track loaders had little competition digging and loading jobs.

Now, the lower owning and operating costs, versatility and acquisition costs of hydraulic excavators are making track loaders a "thing of the past"...

References

* Caterpillar Performance Handbook. Peoria, Illinois: Caterpillar Tractor Company. Serial Publication.