Initially, the main tools of woodcutters were a saw and an ax. In the future, they were replaced by chainsaws and loppers. Labor productivity has increased, but not so much as to satisfy procurers. The development of machines capable of replacing several workers at once began.
At first, the whole process was divided into two independent technological cycles. The felling machine cut and stacked the whip, the delimber cleared the trunk from branches. There was a time interval between the works due to the need to feed the whip for cleaning. But the developers managed to create a complex harvesting equipment with a primary processing function.
What is a harvester? This word literally translated from English means "gatherer". As applied to logging, this is a self-propelled machine that first cuts a tree trunk, then cleans it from knots, bucks it into elements according to grades, and then distributes these parts into one-size packs.
The entire complex is based on a chassis - wheeled, tracked or combined. The choice between the types is dictated by the conditions in which the machine is supposed to be used. The width of the wheels or tracks is sufficient to provide good traction and stability on soft soil, but if working in swampy areas, the second option is preferred.
A comfortable tractor-type cab is located on the frame, from which the operator sets the necessary operations. Control is carried out through programmable controllers, each of which is responsible for its own module: engine, frame, cab, automatic gearbox, manipulator and head. By manipulating special joysticks, the operator achieves the desired result. A small monitor located in front of a specialist helps to control the process.
The work of the harvester for timber processing is carried out with the help of the harvester head - the main tool of the combine. In fact, this is a separate complex mechanism with grippers, circular saws, edging knives. The head is mounted on a hydraulic manipulator of sufficient power to position the head with the barrel in different planes. The arm of the manipulator reaches 70 meters or more.
The more powerful the harvester, the thicker the trunk the machine can handle. They are divided into the following classes: