Cold planer
With cold milling asphalt concrete and gravel layers of different thickness are removed. The cold milling machine moves over the abzufräsende layer, wherein a rotating milling drum is lowered according to the routing depth and the material dissolves. The milling machine can be used both in parallel and in a certain inclination to the roadway surface to the road surface. During the milling the set milling depth with respect to a predetermined reference level can be controlled.
The milled material obtained is loaded depending on the construction site construction methods and the logistical requirements of a loading conveyor to trucks, placed at the side or left in the remaining milled track. In small milling machines that are used when smaller areas are processed or when milling in restricted space, is also often worked without loading conveyor.
Cold milling machines are available in different sizes. The small machines have working widths of about 0.30 m to 1.00 m. Large milling machines are available with working widths up to 3.80 m. In Germany hardly milling about 2.20 m are used for logistical reasons, since such a milling machine including low loader and tractor brings about 70 t total weight with it and also in transport height and width is borderline.
From fine milling is used when the asphalt layer should not be replaced but may be driven by the step immediately. For this purpose, other rollers at a higher bit number are related. A subspecies of the fine milling is the vertical fine milling, here is a vertical milling machine Santander chisel plate in use, the local irregularities ( road markings, bus bays ) or can mill out manhole covers.
History
Predecessor of the cold milling machine is the hot milling machine that works on the same principle, but can only edit a strongly heated surface. This process has in comparison to the cold milling machine much higher energy costs (gas consumption for heating ) and works more slowly or at shallower depths than with the cold variant is possible. Another point is the enormous oxygen consumption, makes the hot milling impossible in closed buildings. Thus, a router when editing an ice rink, for example, have fainted, because the atmospheric oxygen content in the course of work plummeted too strong. Despite these drawbacks, hot milling was the first opportunity for effective road rehabilitation because high forces occur during cold milling, the strain on the entire machine tremendously. Not only the cutting tools must be made of high-tensile special steel, and roller drive, bearings and mudguards have high mechanical loads. In the early 1980s the first cold milling machines have been mass-produced and first company specialized in this Sanierungsart. Today cold milling is the most common construction method in the rehabilitation of roads. Wirtgen GmbH is a world leader in the field of cold milling. With a total of 16 different machines, it offers the most comprehensive cold milling program in the industry.