Truck cranes are cranes mounted on the chassis of an ordinary car or a chassis of a special purpose car, with the driving cab separated from the crane cab. The advantage of this crane is mobility, rapid transfer. The downside is that you have to work on legs, can not afford to drive, and are not suitable for working on soft or muddy grounds. Truck crane chassis performance equivalent to the same total weight of the truck, in line with the technical requirements of road vehicles, which can be unimpeded access on all types of roads. Such cranes are generally available on the alley, get off two control room, the work must extend the legs to maintain stability. From a large range of weight, from 8 tons to 1,600 tons, the number of chassis axles, from 2 to 10. Is the largest production, the most widely used type of crane.
Underneath the boom there is a revolving drum around the wire rope which is pulled through the pulleys on the top of the next boom by the last boom and so on. When retracted, the drum reverses and rewinds the wire rope and the boom retracts under its own weight. The rotating drum is powered by a hydraulic motor, so you can see two tubing, but do not use it as a cylinder.
In addition there are some truck crane telescopic boom installed inside the plug-type cylinder, but such applications are rare. Because multi-stage ram cylinders are expensive and the boom flexes flexibly when loaded, this has a significant impact on cylinder life.
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