Semi-trailer Aerodynamic Device
   HOME
*



picture info

Semi-trailer Aerodynamic Device
A semi-trailer is a trailer without a front axle. In the United States, the term is also used to refer to the combination of a truck and a semi-trailer; a tractor-trailer. A large proportion of a semi-trailer's weight is supported by a tractor unit, or a detachable front-axle assembly known as a dolly, or the tail of another trailer. The other portion of the semi-trailer's weight is semi-supported (half-supported) by its own wheels, which only support the rear of the semi-trailer. A semi-trailer is normally equipped with landing gear (legs which can be lowered) to support it when it is uncoupled. Many semi-trailers have wheels that are capable of being totally dismounted and are also relocatable (repositionable) to better distribute load to bearing wheel weight factors. Semi-trailers are more popular for transport than full trailers, which have both front and rear axles. Ease of backing is cited as one of the semi's chief advantages. A road tractor coupled to a semi-trailer ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




I40TruckCTI
I4, i4, I 4 or I-4 may refer to: Arts, entertainment, and media * '' I-4: Loafing and Camouflage'', a Greek film Military * 1st Life Grenadier Regiment (Sweden) (1816–1927), a Swedish infantry regiment * , a World War II Type J1 submarine of the Imperial Japanese Navy * Life Grenadier Regiment (Sweden) (1928–1997), a Swedish infantry regiment * Tupolev I-4, a 1927 Soviet aircraft Science and technology * I-4 satellite * i4, an integer in XML-RPC Transportation * I4 engine, a piston engine * Interstate 4, an interstate highway in Florida * BMW i4, a German mid-size electric sedan * Interstate Airlines, by IATA airline designator * LB&SCR I4 class, a British locomotive See also * iPhone 4 The iPhone 4 is a smartphone that was designed and marketed by Apple Inc. It is the fourth generation of the iPhone lineup, succeeding the iPhone 3GS and preceding the 4S. Following a number of notable leaks, the iPhone 4 was first unvei ...
, a smartphone {{Lette ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Mack Trucks
Mack Trucks, Inc., is an American truck manufacturing company and a former manufacturer of buses and trolley buses. Founded in 1900 as the Mack Brothers Company, it manufactured its first truck in 1905 and adopted its present name in 1922. Mack Trucks is a subsidiary of AB Volvo, which purchased Mack along with its then parent company Renault Véhicules Industriels in 2000. Founded originally in Brooklyn, New York in 1900, the company's headquarters were moved to Allentown, Pennsylvania in 1905 where they remained until 2009. In 2009, its headquarters were relocated to Greensboro, North Carolina. Mack products are produced in Lower Macungie, Pennsylvania, and Salem, Virginia, with all powertrain products produced in its Hagerstown, Maryland plant. Mack also maintains additional assembly plants in Pennsylvania, Australia, and Venezuela. The company also once maintained plants in Hayward, California and Oakville, Ontario, though both of these have been closed. Operations The c ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Scammell Mechanical Horse
The concept of the Mechanical Horse tractor unit with an easily detached articulated trailer was conceived in the early 1930s by Napier & Son. It has one front wheel in the midline. The London and North Eastern Railway had approached Napier for an answer to the problem of replacing horses for local haulage purposes, while retaining the flexibility of changing the wagons and the maneuverability of the horse and wagon. These vehicles are often known as "Snub-nose Trucks" or "Snub-nose Lorries" because of the round hood in front of the cab. Mechanical Horse In 1933 Scammell Lorries Ltd purchased the three wheeled tractor unit design from the Napier Company and promptly turned it into the famous Mechanical Horse. Production of the 3-wheeled Mechanical Horse commenced in 1934. The design had been refined in 1933 by Oliver Danson North, who modified the original prototype. This featured automatic trailer coupling and the single front wheel could be steered through 360 degrees. Thi ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Air Brake (road Vehicle)
An air brake or, more formally, a compressed-air-brake system, is a type of friction brake for vehicles in which compressed air pressing on a piston is used to apply the pressure to the brake pad or brake shoe needed to stop the vehicle. Air brakes are used in large heavy vehicles, particularly those having multiple trailers which must be linked into the brake system, such as trucks, buses, trailers, and semi-trailers, in addition to their use in railroad trains. George Westinghouse first developed air brakes for use in railway service. He patented a safer air brake on March 5, 1872. Westinghouse made numerous alterations to improve his air pressured brake invention, which led to various forms of the automatic brake. In the early 20th century, after its advantages were proven in railway use, it was adopted by manufacturers of trucks and heavy road vehicles. Design and function Air brakes are typically used on heavy trucks and buses. Typical operating pressure is approximat ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Fifth-wheel Coupling
The fifth-wheel coupling provides the link between a semi-trailer and the towing truck, tractor unit, leading trailer or dolly. The coupling consists of a kingpin, a vertical steel pin protruding from the bottom of the front of the semi-trailer, and a horseshoe-shaped coupling device called a ''fifth wheel'' on the rear of the towing vehicle. As the connected truck turns, the downward-facing surface of the semi-trailer (with the kingpin at the center) rotates against the upward-facing surface of the fixed fifth wheel, which does not rotate. To reduce friction, grease is applied to the surface of the fifth wheel. The configuration is sometimes called a ''turn-table'' in Australia and New Zealand, especially if it is a rotating ball-race-bearing type. The advantage of this type of coupling is towing stability. Some camper trailers also use a fifth-wheel configuration, with the coupling installed in the bed of a pickup truck as a towing vehicle; "fifth wheel" is therefore ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Railway Track
A railway track (British English and UIC terminology) or railroad track (American English), also known as permanent way or simply track, is the structure on a railway or railroad consisting of the rails, fasteners, railroad ties (sleepers, British English) and ballast (or slab track), plus the underlying subgrade. It enables trains to move by providing a dependable surface for their wheels to roll upon. Early tracks were constructed with wooden or cast iron rails, and wooden or stone sleepers; since the 1870s, rails have almost universally been made from steel. Historical development The first railway in Britain was the Wollaton Wagonway, built in 1603 between Wollaton and Strelley in Nottinghamshire. It used wooden rails and was the first of around 50 wooden-railed tramways built over the next 164 years. These early wooden tramways typically used rails of oak or beech, attached to wooden sleepers with iron or wooden nails. Gravel or small stones were packed around ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Beam (structure)
A beam is a structural element that primarily resists loads applied laterally to the beam's axis (an element designed to carry primarily axial load would be a strut or column). Its mode of deflection is primarily by bending. The loads applied to the beam result in reaction forces at the beam's support points. The total effect of all the forces acting on the beam is to produce shear forces and bending moments within the beams, that in turn induce internal stresses, strains and deflections of the beam. Beams are characterized by their manner of support, profile (shape of cross-section), equilibrium conditions, length, and their material. Beams are traditionally descriptions of building or civil engineering structural elements, where the beams are horizontal and carry vertical loads. However, any structure may contain beams, for instance automobile frames, aircraft components, machine frames, and other mechanical or structural systems. In these structures, any structural element, ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Pipe (fluid Conveyance)
A pipe is a tubular section or hollow cylinder, usually but not necessarily of circular cross-section, used mainly to convey substances which can flow — liquids and gases ( fluids), slurries, powders and masses of small solids. It can also be used for structural applications; hollow pipe is far stiffer per unit weight than solid members. In common usage the words ''pipe'' and '' tube'' are usually interchangeable, but in industry and engineering, the terms are uniquely defined. Depending on the applicable standard to which it is manufactured, pipe is generally specified by a nominal diameter with a constant outside diameter (OD) and a schedule that defines the thickness. Tube is most often specified by the OD and wall thickness, but may be specified by any two of OD, inside diameter (ID), and wall thickness. Pipe is generally manufactured to one of several international and national industrial standards. While similar standards exist for specific industry app ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Trunk (botany)
In botany, the trunk (or bole) is the stem and main wooden axis of a tree, which is an important feature in tree identification, and which often differs markedly from the bottom of the trunk to the top, depending on the species. The trunk is the most important part of the tree for timber production. Occurrence Trunks occur both in "true" woody plants and non-woody plants such as palms and other monocots, though the internal physiology is different in each case. In all plants, trunks thicken over time due to the formation of secondary growth (or in monocots, pseudo-secondary growth). Trunks can be vulnerable to damage, including sunburn. Vocabulary Trunks which are cut down for making lumber are generally called logs; if they are cut to a specific length, called bolts. The term "log" is informally used in English to describe any felled trunk not rooted in the ground, whose roots are detached. A stump is the part of a trunk remaining in the ground after the tree has been f ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Shunt Truck
A terminal tractor, known in the United States as a shunt truck, spotter truck, spotting tractor, yard truck, yard shifter, yard dog, yard goat, yard horse, yard jockey, hostler, or mule, is a kind of semi-tractor intended to move semi-trailers within a cargo yard, warehouse facility, or intermodal facility, much like a switcher locomotive is used to position railcars. In the United Kingdom they are known as terminal lorries. Characteristics Distinctions between a terminal tractor and a regular tractor unit include: *A single-person cab offset to the side of the engine. *A full-height, sliding rear door for easy access to trailer connections. *A very short wheelbase, usually with a solidly mounted rear axle. *A low-power diesel, alternative fuel engine, or electric motor usually with an automatic transmission. *A fifth-wheel coupling with an integrated lifting mechanism allows the semi-trailer's legs to remain in the lowered position during movement. and of hydrauli ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Drawbar (haulage)
A drawbar is a solid coupling between a hauling vehicle and its hauled load. Drawbars are in common use with rail transport, road trailers, both large and small, industrial and recreational, and with agricultural equipment. Agriculture and horse-drawn vehicles Agricultural equipment is hauled by a tractor mounted drawbar. Specialist agricultural tools such as ploughs are attached to specialist drawbars which have functions in addition to transmitting tractive force. This was partly made redundant with Ferguson's development of the 3 point linkage in his famous TE20. A wooden ''drawbar'' extends from the front of a wagon, cart, chariot or other horse-drawn vehicles to between the horses. A steel ''drawbar'' attaches a three-point hitch or other farm implement to a tractor. Road A drawbar is a towing or pushing connection between a tractive vehicle and its load. Light vehicles On light vehicles, the most common coupling is an A-frame drawbar coupled to a 1 7/8 inch or 50 ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Trailer (vehicle)
A trailer is an unpowered vehicle towed by a powered vehicle. It is commonly used for the transport of goods and materials. Sometimes recreational vehicles, travel trailers, or mobile homes with limited living facilities where people can camp or stay have been referred to as trailers. In earlier days, many such vehicles were towable trailers. United States In the United States, the term is sometimes used interchangeably with travel trailer and mobile home, varieties of trailers and manufactured housing designed for human habitation. Their origins lay in utility trailers built in a similar fashion to horse-drawn wagons. A trailer park is an area where mobile homes are placed for habitation. In the United States trailers ranging in size from single-axle dollies to 6-axle, high, long semi-trailers are commonplace. The latter, when towed as part of a tractor-trailer or "18-wheeler", carries a large percentage of the freight that travels over land in North America. Types ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]