1. Initial Development
People's initial development is to follow the track of agricultural crawler tractor. In 1915, the British-developed "Little Tramp" tank followed the tracks of the American "Brock" tractor. In 1916, the French developed "Schnader" and "Saint-Chamoun" tanks followed the tracks of the American "Holt" tractor. Track has been in the history of tank for nearly 90 years. Today's track, no matter its structure form, materials and processing, is constantly enriching the treasure house of tank. Track has developed into a tank "infinite track" that can stand the test of war.
2. Track classification
Tank tracks can be divided into two categories according to the structure type: metal pin hinge type and metal rubber hinge type. Among them, the metal rubber hinge can be divided into single pin type and double pin type two.
The metal pin track has simple structure, direct dry friction between the pin and the pin hole, rapid wear and tear, and short service life. During tank maintenance, it is often found that the track pin is ground into a "sugar-coated" shape. track pin is also one of the wearing parts.
Metal rubber hinged track, is in the metal pin vulcanized more than rubber sleeve ring, pressure with the track plate pin hole, so, there is no direct friction between the track pin and track plate pin hole, torsion only rubber sleeve ring elastic torsion, low noise, long life, of course, the structure is also complex, high cost. The double-pin metal rubber track is connected with the two pins of two track plates by the end connector. It has good stress and is convenient to disassemble and assemble, but its structure is complex. It is the mainstream track form on the main battle tank.
Three active
A driving wheel is a driving component consisting of a hub, ring gear, toothed gasket, conical cup, retaining nut and stop bolt. It meshes the gear and the track and transfers the power from the side reducer to the track to make the tank move.
The inducer is a driven wheel that is used to induce and support the track and, together with the track regulator, to adjust the tightness of the track. It is composed of hub, wheel disc, ball bearings, wheel shaft cover, fixed nut, double row ball bearings, support cup and return oil cover.
The belt pulley is mainly used to support the upper track, without this belt pulley, the track will crash. One end of the belt axle is firmly fixed on the body of the car. Since the diameter of the bearing wheel is smaller than the roadwheel, its bearing speed is much higher, but it only supports the upper track, which is 1/3 of the track weight, to reduce the oscillation of the track.
The track regulator is used to adjust the tightness of the track. It is composed of support, arm, shaft sleeve, worm gear, worm, screw, friction film and bushing. The tensioning degree of the track has great influence on the driving and the life of the track of the tank. The tracks are too tight or too loose. Different operating environments require the crawler to have different tightness. If driving on a hard road, the track should be tensioned; In desert areas, the tracks should be stretched loose. In addition, as the wear of the track pin and pin hole increases, the track will become loose. In order to maintain the appropriate tension of the track, it is necessary to use the track regulator to adjust the tightness of the track. This is to change the track tension by changing the distance between the induction wheel and the driving wheel with the help of the track regulator. The track regulator makes the inducer swing back to a certain position, and the inducer moves away from the driving wheel, so the track is tensioned. The track regulator makes the induction wheel swing forward to a certain position, and the track becomes loose.
4 of The roadwheels are used to support the weight of the tank and its proper tracks. It's made of wheels, wheels, tape,
Ball bearing, axle cover, fixing nut, winding oil cover, etc. The large number of roadwheels can make each wheel bear less weight, and the pressure on the ground is evenly distributed, which is beneficial to improve the performance of the tank.
When the power of the engine is transferred to the driving wheels, the driving wheels move the tracks in a clockwise direction, thus creating an interaction force between the ground tracks and the ground. According to the principle of action and reaction of force, the track gives a force to the ground along the horizontal direction, and the ground gives a reaction force to the track. This reaction force makes the tank move, which is called the traction force of the tank.
5 Structural materials
The special track material and structure have two major characteristics, the fiber is made of DuPont Kevlar fiber, rather than the steel wire used in ordinary tracks. Kevlar fiber has the advantages of high strength, light weight, high modulus, no shrinkage and so on. The tires used by several famous cars in the world all use this material as the skeleton. The inner reinforcement frame of the crawler adopts the space material carbon fiber frame instead of the traditional cast steel frame. Kevlar is three times stronger than steel wire, while carbon fiber is four times stronger than cast steel. The phenomenon of wire stripping, tooth stripping and tooth breaking existing in the traditional track will not appear on the special track at all.
Because of the high cost of the material itself, the price of special tracks is about 30% higher than that of traditional tracks. So customers can choose different designs and different materials according to their own design requirements.
6 Track chassis
Rubber rubber shoe
Rubber rubber track chassis is mostly suitable for small light industry and small construction machinery industry. Light industry is generally agricultural machinery of less than one ton to four tons. Construction machinery industry is more used for small drilling industry.
The choice of operating environment is generally as follows:
(1) The service temperature of rubber track is generally between -25 ~ +55 'C.
(2) Chemicals, motor oil and salt of sea water will speed up the aging of the tracks. After use in such an environment, the tracks should be cleaned
(3) Roads with sharp protrusions (such as steel bars, stones, etc.) will cause injury to the rubber tracks.
(4) Road edge stone, ruts or uneven road surface will lead to track edge ground side pattern cracks, this crack can continue to use when it does not hurt the wire curtain.
(5) Gravel and gravel pavement will cause early wear on the rubber surface in contact with the bearing wheel, forming small cracks. Serious water intrusion, resulting in core iron off, wire fracture.
Steel tracks
Comparatively speaking, the steel track has a wider range of service life and the choice of working conditions. It is composed of steel tracks, moving wheels, guide wheels, supporting wheels, chassis and two walking reducer units (walking reducer by motor, gearbox, brake, valve body composition). Generally, for example, the drill rig is arranged on the chassis as a whole, and the walking speed of the track chassis can be adjusted by the control handle, so that the whole machine can realize convenient movement, turning, climbing and walking.
