snow plow
A snow plow is a device used to clear snow both on the road and in rail traffic .
history
In the past, snow plows (so-called "railway sleds") were pulled by oxen or horses as draft animals . These were mostly wooden wedge plows . However, this had the disadvantage that the animals had to walk in front of the plow and thus compacted the snow. You couldn't raise or lower the plow, only load it with stones.
Designs
Street
There are wedge plows and snow plows with a straight share. The wedge plow has two inclined snow blades which are connected in a wedge shape at the front and create snow walls on both sides of the plow. While the wedge plows are mostly only used for clearing single-lane roads or also on the railroad, snow plows with a straight plowshare are usually used on multi-lane roads. Straight shares can be swiveled to the left or right, depending on which side the snow is to be cleared. The flock is usually curved from top to bottom, so that a better snow throw occurs.
The snow plow for the road is usually mounted on a special mounting plate at the front of a truck , a municipal equipment carrier or a tractor . The plow can usually be raised, lowered and swiveled hydraulically . In addition to the front attachment, there are also snow plows attached to the side or rear (mostly only on tractors for clearing smaller areas).
Flocks of snow plows for the road area have a hard-wearing edge, the scraper, on the underside that touches the road. The scraper is made of composite material, usually made of steel, corundum , rubber and possibly hard metal. Scraper strips made only of rubber and corundum are also used for pavement. The scraper is designed as a quickly replaceable wear part. The share is usually tiltable so that unevenness cannot lead to damage. Snow plows are pressed to the ground by their weight alone (several hundred kg up to several tons in the case of oversized airport snow plows). There are supports or support wheels directly behind the snow plow so that the plow does not go into the ground and start digging.
So that the driver of the vehicle can see where he can drive the plow, colored snow poles (also snow sticks or snow signs) are often driven in at the roadside (especially on open-air roads ) . If the driver is to be informed that he has to lift the plow, a cross (red X, made of approx. 20 cm long wooden strips) is attached to the snow pole in some regions. Also red crossbars, possibly with support struts, indicate the location and the beginning of a sidewalk edge or a ramming board (on bridges ). These signs have been on Alpine passes for more than half a year.
For wider lanes such as motorways , winter service vehicles are often used which, in addition to the front plow, also have a swiveling side plow on the side facing the edge of the road. For example, several snowploughs, one behind the other, are often staggered at an angle and clear the entire roadway from snow in one pass. Overtaking this convoy is very dangerous because you can get directly into the uncleared area of the road from the first cleared area. In some states such as North Rhine-Westphalia and Baden-Wuerttemberg vehicles winter maintenance are also equipped with flashing lights and sirens equipped to z. B. in the event of a traffic jam, if necessary, to be able to drive against the direction of travel on the motorway or to drive through the traffic jam .
Special plows can be up to 15 m wide with these booms. Such vehicles can only z. B. used at airports . There, too, three plows are needed to clean the 40 m wide runway . Often the snow plows also have automatic spreading machines for grit or road salt installed at the rear. The truck has more weight due to the loaded grit and therefore more traction . But there are also snow plows in small versions, which z. B. can be mounted on motor mowers , pickups or small tractors , with which you can clean sidewalks or garden paths in parks . A hand-held snow plow usually has rollers that absorb the lateral force.
If the snow depth is too high, the snow is very heavy or you cannot store the snow directly on the edge, you can use snow blowers .
Typical for many snow plows are headlights and indicator lights that are raised above the top edge of the shield, often also marker lights on the upper corners of the shield and auxiliary lights on the cab roof, i.e. above eye level of the driver, which thanks to their location illuminate the area close in front of the shield from the driver’s perspective. Some snow guiding boards above the shield are made of transparent plastic in order to improve the view of the road section directly in front of them when stationary or when driving slowly.
rail
Numerous locomotives , railcars and control cars have small track clearers on the bogies , whose main task, however, is not to clear snow, but to remove small foreign objects in the track area . In snowy areas of operation (Alps, Scandinavia) these rail clearers are often enlarged to form small snow plow flocks. The railway administrations have mobile snow plows for larger operations. The Deutsche Bahn AG are snow plows of the type Meiningen from the holdings of Deutsche Reichsbahn , and snow plows Beilhack the type of the German Federal Railways are available. The Reichsbahn snow plows were first built in the former RAW Halberstadt and then in the Reichsbahn repair shop in Meiningen , while the Bundesbahn devices were built by the Beilhack company in Rosenheim or today in Kiefersfelden . The Meiningen plant is responsible for the maintenance of all clearance vehicles at Deutsche Bahn AG.
Before the Second World War , the former Deutsche Reichsbahn (DR) , like many other railway administrations, converted decommissioned tenders and some decommissioned Bavarian electric locomotives into so-called climate snow plows , named after their inventor, the Austrian Rudolf Klima. Two air-conditioned snow plows, converted from tenders , can be seen in the German Steam Locomotive Museum . A converted electric locomotive is in the inventory of the Bavarian Railway Museum .
Snow plows used to be one-way vehicles . A turntable (or a possibility to turn around) was necessary so that the vehicles could be used in the other direction of travel . Modern devices are bidirectional vehicles ; the clearing device can be rotated to prepare the vehicle for the other direction of travel without using a turntable. This new option is necessary today because turntables are practically nonexistent in rail operations.
In snowy countries, so u. a. In Austria, rail- mounted snow blowers or - earlier - snow blowers are also used.
The Rhaetian Railway uses special track plows in front of regular trains, which can clear the rail profile to below the top edge of the track . These are equipped with clearing blades that can be lowered and raised remotely in order to still be able to drive on points.
When there is less snowfall, however, it is sufficient to keep the tracks free of snow by means of so-called track journeys , which are carried out with regular vehicles.
See also
- Snow plowing (sport)
- Snow blower
literature
- HA Pierer (Ed.): Universal Lexicon of the Present and Past or the latest encyclopedic dictionary . Volume 8, D-Doit, 3rd edition, Altenburg 1841, p. 86.
- H. Besson: Sleigh plow for shoveling the snow in the mountains . In: Johann Gottfried Dingler, Emil Maximilian Dingler (ed.): Dinglers polytechnisches Journal . Volume 20, JG Cotta'sche Buchhandlung, Stuttgart 1826, pp. 244-247.
Web links
Individual evidence
- ↑ Handbook of engineering . Volume 4, Issue 3, Part 4, Verlag Engelmann, 1887, pp. 65–69.
- ↑ ÖBB snow chaos: Help for Carinthia ORF.at of February 3, 2014
- ↑ http://www.gartenbahn-toffeholz.ch/spurpflug.html