The Story On Excavator Tracks
Excavators, as we all know are engineering vehicles that are used for a variety of purposes, mostly related to the moving of materials such as rocks and earth from one place to another. Excavator tracks or wheels are one of the most immediately noticeable features of any excavator; so noticeable even laymen can spot this immediately. Excavator tracks and wheels are of course, mounted under the machine undercarriage as a means of locomotion.
Excavator tracks, are related to tracks found in other earthmoving machines, off-road vehicles (like snowmobiles), and those found in tanks and other military vehicles. The main advantage of a track system for locomotion over wheels is the superior weight distribution. Tracks are often used on heavy vehicles for this very reason. Bad weight distribution can cause vehicles to sink in soft ground or to damage roads. Tracked vehicles are also more maneuverable, being able to turn on a particular spot.
Tracks used today, including excavator tracks come in two varieties: metal (usually steel) and rubber. The both kinds used today are typically called "caterpillar tracks". Crude caterpillar tracks were invented in the late 18th century for steam powered vehicles by an Englishman named Richard Lovell Edgeworth. Refinements of his concept of interlocking track segments joined together to improve weight displacement are still being made to this very day.
Tracks made today are typically modular hinged steel links that are combined to form a closed or continuous chain. These chains are typically made broad to provide optimum weight distribution. Sprockets or wheels then drive the flexible track to provide locomotion for the vehicle. There was a competing system to caterpillar tracks called a Kégresse track, which found use during the first half of the 20th century but has since been overtaken by improvements in caterpillar tracks and is now considered obsolescent. In contrast to a caterpillar track, a Kégresse track was not composed of joined segments. Instead, a continuous rubber track was used. A different drive system from sprockets was also used. This type of tracks had the advantage of being suitable for paved roads. On the other hand, these were easily damaged beyond utility in adverse conditions and consequently, had not found widespread use after WWII. A few excavator tracks were made with this system. Caterpillar tracks, including those used as excavator tracks, are often made out of metal, usually steel. The advantage of using metal is that it is extremely durable and flattens out bumps. However roads are easily damaged by steel tracks. A solution to this problem was to put rubber pads on each track segment but this generally buts a great strain on the workings of engines. Another solution is a hybrid of Kégresse and Caterpillar tracks that now finds widespread use as excavator tracks. They retain most of the advantages of using tracked systems and of steel tracks and can be used on roads without damaging them. They are also supported by pneumatic air pressure as in rubber wheels and hence similarly to steel tracks, cannot be punctured. Some of these are made of rubber encased metal links, while others are continuous rubber tracks. They are all quieter than steel tracks, exert less pressure on the ground, are much lighter, and are generally cheaper. However, they are not nearly as durable as steel tracks. All these things should be weighed when choosing a model of excavator with a particular system of excavator tracks.
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