semi-trailer is a trailer with no front axis. In the US, the term is also used to refer to a combination of truck and semi-trailer, a tractor-trailer.
Most semi-trailer weights are supported by a tractor unit, or a removable front axle assembly known as a dolly, or other trailer tail. A semi-trailer is usually equipped with a landing gear (legs that can be lowered) to support it when it is released. Many semi-trailers have fully capable down wheels and can also be moved (repositioned) to distribute a better load to the bearing wheel weight factor. Semi trailers are more popular for transportation than full trailers, which have front and rear axes. The ease of support is referred to as one of the major advantages of semi. Road tractors paired with semi-trailers are often called semi-trailer or "semi" trucks in North America & amp; Australia, and articulation trucks or "artic" in the UK.
A trailer semi-trailer with two trailer units is called B-doubles (Australian English) or tandem tractor trailer , tandem rig , or double (American English). Other terms used are "B-train" or (when there are three or more trailers) "train". The combination of double coupling is possible with the use of dolly, or "dolly converter" (Australian and American English), essentially one to three additional axles placed under the front of the second carriage. The first semi-trailer is connected to the power unit using a five-wheeled tractor clutch while the dolly converter, which is mounted to the second semi-trailer, connects to the first semi-trailer with the drawbar. In Australian English, the tractor unit is called "prime-mover", and the combination of prime-mover and trailer is known as "semi-trailer", "semi" or single.
Video Semi-trailer
Properties
The road and semi-trailer tractors carry most of the transportation. With 1170117 ton-kilometers transported in this way in the EU, including the UK, road and semi-trailer tractors are 77.6% of the total tonne-kilometers transported by 2015, according to Eurostat.
In road haulage, semi-trailers dominate more than full trailers because of their versatility. Trailers can be paired and separated quickly, allowing them to be connected to the load and loaded among the depots. If the power unit fails, another tractor can replace it without disturbing the cargo.
Compared to the full trailer, the semi-trailer attached to the tractor unit is easier to reverse, because it has only one turning point (clutch), while the full trailer has two turning points (clutch and attachment drawbar). Special tractors known as shunt trucks or shuttle trucks can easily maneuver trailers in depots or load and lower ferry loads. This tractor can lift the clutch so that the trailer foot clears the ground.
A rigid truck and full trailer are articulated inside the payload area, so the semi-trailer can have a longer and more sustainable cargo area. Therefore, semi-trailers can carry longer items (wood blocks, pipes, blocks, railways). It depends on the law; in some European countries, full trailers can be along semi-trailers. However, since the rigid truck is longer than the semi-tractor, it increases the overall length of the combination, making it less maneuverable.
Maps Semi-trailer
Clutch
Both types of clutch are the fifth and automatic clutch. In some applications, no separate clutches are installed, and trailers are trucked into the tractor unit, using bearings, and rocking legs such as those used under the fifth wheel skid plate.
Fifth wheel coupling
The towing vehicle has a broad coupling plate known as a fifth-wheel clutch welded to the chassis in which the semi-trailer is resting and pivoted. When the tractor is overturned underneath the trailer, the kingpin below the front of the trailer slid into the crack in the skateboard, and the fifth jaws of the wheels approached. The driver must manually raise the foot of the trailer, and pair the airbrake line and the power cord. Some low-set trailers such as lowboys/low-loader and car transporters have electric-powered landing gear because low clearance certainly prohibits conventional landing gear.
Automatic clutch
Years ago, the clutch automatically dominated, but now is quite rare. Automatic couplings are commonly used for a short 12 ton (11 Â °) or less, eg. on Scammell Mechanical Horse.
No coupling plate used on the tractor; turntables are permanently mounted on the bottom of the trailer. It locks the tractor chassis. When the tractor is reversed under the trailer, its legs go up and the brakes and electrical connections are made automatically. Almost the entire clutch and uncoupling procedure is operated by the driver from inside the cabin, except that it has to go down to release (or apply) the trailer parking brake.
Type
Different types of semi-trailers are designed to transport different cargoes.
Jenis cuplikan
Lihat juga
Referensi
Tautan eksternal
- Media terkait dengan Semi-trailer di Wikimedia Commons
- Pembuat dan penjual semi trailer di Curlie (berdasarkan DMOZ)
Source of the article : Wikipedia
0 Comments