Truck

From New World Encyclopedia
"Lorry" redirects here.
A "straight-job" International moving truck.
DAF tractor with an auto-transport semi-trailer truck carrying Škoda Octavia cars in Cardiff, Wales
File:Logging truck.jpg
An Australian prime mover Kenworth and B double trailer combination
File:P 1217.14 Palencia.JPG
Spanish Pegaso 1217.14 tank truck

A truck is a motorized vehicle usually used for transporting bulk goods, materials, or equipment. The word "truck" comes from the Greek word trochos, meaning "wheel." In North America, the big wheels of wagons were called trucks. When the gasoline-engine-driven trucks became available, these were called "motor trucks."

Lorry is a British term for a truck, but it is used only for the medium and heavy types. A van, pickup truck, or Jeep would not be called a "lorry." Other languages have loanwords based on these terms, such as the Malay lori and the Mexican Spanish troca (or pickup in northern Mexico).

In Australia and New Zealand, a small vehicle with an open back is called a ute (short for "utility vehicle") and the word "truck" is reserved for larger vehicles.

Anatomy of a truck

Almost all trucks share a common construction: they are made of a chassis, a cab, an area for placing cargo or equipment, axles, suspension and wheels, an engine, and a drivetrain. Pneumatic, hydraulic, water, and electrical systems may also be identified. They are complex machines. Many also tow one or more trailers or semi-trailers.

Cab

Scania R470 flat nose truck

The cab is an enclosed space where the driver is seated. A sleeper is a compartment attached to the cab where the driver may rest while not driving, sometimes seen in semi-trailer trucks.

Cabs can be built in a few possible configurations:

  • Cab over engine (COE) or flat nose, where the driver is seated on top of the front axle and the engine. This design is almost ubiquitous in Europe, where overall truck lengths are strictly regulated. They were common in the United States, but lost prominence when permitted length was extended in the early 1980s. To access the engine, the whole cab tilts forward, earning this design the name of tilt-cab. This type of cab is especially suited to the delivery conditions in Europe where many roads follow the layout of much more ancient path and trackways which require the additional turning capability of the cab over engine type.
US truck with long nose and sleeper cab
  • Conventional cabs are the most common in North America, and are known in the UK as American cabs. The driver is seated behind the engine, as in most passenger cars or pickup trucks. Conventionals are further divided into large car and aerodynamic designs. A "large car" or "long nose" is a conventional truck with a long (6 to 8 foot (1.8 to 2.4 m) or more) hood. With their very square shapes, these trucks experience a lot of wind resistance and typically consume more fuel. They also provide somewhat poorer visibility than their aerodynamic or COE counterparts. By contrast, Aerodynamic cabs are very streamlined, with a sloped hood and other features to lower drag. Most owner-operators prefer the square-hooded conventionals.[citation needed]
  • Cab beside engine designs also exist, but are rather rare.

Engine

Trucks can use all sorts of engines. Small trucks such as SUVs or pickups, and even light medium-duty trucks in North America and Russia will use gasoline engines. Most heavier trucks use four stroke turbo intercooler diesel engines, although there are alternatives. Huge off-highway trucks use locomotive-type engines such as a V12 Detroit Diesel two stroke engine.

North American manufactured highway trucks almost always use an engine built by a third party, such as CAT, Cummins, or Detroit Diesel. The only exceptions to this are Volvo and its subsidiary Mack Trucks, which are available with own engines. Freightliner, Sterling Trucks and Western Star, subsidaries of DaimlerChrysler, are available with Mercedes-Benz and Detroit Diesel engines. Trucks and buses built by the Navistar International can also contain International engines. The Swedish truckmaker Scania claims they stay away from the U.S.-market because of this third party tradition.

In the European union all truck engines must comply with Euro 4 regulations, the regulations will become more severe in 2008 with the introduction of Euro 5.

Drivetrain

A logging truck

Small trucks use the same type of transmissions as almost all cars which have either an automatic transmission or a manual transmission with synchronisers. Bigger trucks often use manual transmissions without synchronisers which have less bulk and weight although synchromesh transmissions are used in larger trucks as well. Transmissions without synchronisers known as "crash boxes" require double clutching for each shift, (which can lead to repetitive motion injuries), or a technique known colloquially as "floating," a method of changing gears which doesn't use the clutch, except for starts and stops, due to the physical effort of double clutching especially with non power assisted clutches, faster shifts, and less clutch wear. Double clutching allows the driver to control the engine and transmission revolutions to synchronize, so that a smooth shift can be made e.g. when upshifting, accelerator pedal is released and the clutch pedal is depressed while the gear lever is moved in to neutral, clutch pedal is then released and quickly pushed down again while the gear lever is moved to the next highest gear. Finally, the clutch pedal is released and accelerator pedal pushed down to obtain required engine rpms. Although this is a relatively fast movement perhaps a second or so while transmission is in neutral it allows the engine speed to drop and synchronize engine and transmission revolutions relative to the road speed. Downshifting is performed in a similar fashion except the engine speed is now required to increase (while transmission is in neutral) just a right amount in order to achieve the synchronisation for the smooth non-crunching gearchange. The so called skip changing is also widely used, in principle operation is the same but it requires neutral be held slightly longer than single gearchange. Common North American setups include 9, 10, 13, 15, and 18 speeds. Automatic and semi-automatic transmissions for heavy trucks are becoming more and more common, due to advances both in transmission and engine power. In Europe 8, 10 and 12 gears are common on larger trucks with manual transmission, while automatic or semiautomatic transmission would have anything from 5 to 12 gears. Almost all heavy trucks transmissions are of a "range (double H shift pattern ) and split" type where range change and so called half gears or splits are air operated and always preselected before the main gears selection.

In Europe more new trucks are being bought with automatic or semi-automatic transmission. This may be due in part to lawsuits from drivers claiming that driving a manual transmission is damaging to their knees [citation needed]and the fuel consumption can be lowered and truck durability improved.[citation needed] The primary reason perhaps is the fact that such transmissions give a driver more time to concentrate on the road and traffic conditions.

Chassis

A Polish 1936-built Fiat 621 L fire truck in Warsaw, Poland

The chassis or frame of a truck is commonly constructed mainly of two beams, and several crossmembers. A truck chassis consists of two parallel straight C-shaped beams, or in some cases stepped or tapered beams, these held together by crossmembers. In most instances, gussets help attach the crossmembers to the beams. The "C-shape" of the beams has a middle vertical and longer side, and a short horizontal flange at each end; the length of the beams is variable. The chassis is usually made of steel, but can be made (whole or in part) of aluminium for a lighter weight. The integrity of the chemical composition (carbon, molybdenum, etc.) and structure of the beams is of uttermost importance to its strength, and to help prevent cracking or breaking of beams, and to help maintain rigidity and flexibility of the frame, welding, drilling and other types of modifications should not be performed by unlicenced persons. The chassis is the main structure of the truck, and the other parts attach to it. A tow bar may be found attached at one or both ends.

Environmental effects

Trucks contribute to air, noise, and water pollution in a manner similar to automobiles. In the case of air pollution emissions, a truck's emissions may actually be lower than that of an automobile on a per pound of vehicle mass basis, although the absolute level on a vehicle mile traveled basis is higher, and diesel soot is especially problematic for health.[1]

With respect to noise pollution, trucks emit considerably higher sound levels at all speeds compared to typical automobiles. This contrast is particularly strong in the case of heavy duty trucks.[2]

Concerns have been raised about the effect of trucking on the environment, particularly as part of the debate on global warming. In the period from 1990 to 2003, carbon dioxide emissions from transportation sources increased by 20 percent, despite improvements in vehicle fuel efficiency.[3] In 2005, transportation accounted for 27 percent of U.S. greenhouse gas emission, increasing faster than any other sector.[4] Between 1985 and 2004 in the United States, energy consumption in freight transportation grew nearly 53 percent, while the number of ton-miles carried increased only 43 percent.[5]

According to a 1995 U.S. Government estimate, the energy cost of carrying a ton of freight a distance of one mile averages 514 Btu for water, 337 Btu for rail, 3,100 for trucks, and nearly 20,000 for air transport.[6] Many environmental advocacy organizations favor laws and incentives to encourage the switch from road to rail, especially in Europe.[7]

Quality and sales

The quality of vehicles among all heavy truck manufacturers is generally improving. However, according to some industry insiders, the industry has a long way to go before achieving the quality levels reached by automobile manufacturers. Part of the reason for this is that 75 percent of all trucks are custom built. This works against efforts to streamline and automate the assembly line.

Heavy trucks market worldwide

Largest manufacturers in Western Europe, the U.S. and Japan, over 16 tonnes GVW in 2005.[8]
Pos. Make Units
1 Daimler AG (Mercedes-Benz,Freightliner,Sterling,Unimog,Western Star,Fuso) 241,515
2 Volvo (Volvo,Mack,Renault,UD Nissan Diesel) 177,106
3 PACCAR (DAF Trucks,Kenworth,Peterbilt,Leyland Trucks) 124,406
4 Navistar International Corporation (International,Workhorse 61,066
5 MAN 53,379
6 Scania 53,365
7 Hino Motors (Toyota Group) 44,494
8 Iveco (Iveco,Magirus,Astra,Seddon Atkinson,Yuejin) 43,364
9 Nissan Diesel 25,852
10 Volkswagen 22,684

Insuring trucks for commercial hauling

Primary Liability Insurance coverage protects the truck from damage or injuries to other people as a result of a truck accident. This truck insurance coverage is mandated by U.S. state and federal agencies and proof of coverage is required to be sent to them. Insurance coverage limits range from $35,000 to $1,000,000. Pricing is dependent on region, driving records, and history of the trucking operation.

Motor Truck Cargo insurance protects the transporter for his responsibility in the event of damaged or lost freight. The policy is purchased with a maximum load limit per vehicle. Cargo insurance coverage limits can range from $10,000 to $100,000 or more. Pricing for this insurance is mainly dependent on the type of cargo being hauled.

Gallery

See also

  • Air brake (road vehicle)
  • Automobile
  • Brake
  • Bus
  • Dump truck
  • Flatbed truck
  • Forklift
  • Hybrid truck
  • Pickup truck
  • Refrigerator truck
  • Semi-trailer truck; this article covers large trucks such as road trains and articulated lorries.
  • Trailer (vehicle)

Notes

References
ISBN links support NWE through referral fees

  • Holtzman, Stan. 2005. Big Rigs: The Complete History of the American Semi Truck. [S.l.]: Voyageur Pr. ISBN 978-0896587373.
  • Mike Byrnes & Associates. 2003. Bumper to Bumper: The Complete Guide to Tractor-Trailer Operations. 4th ed. Corpus Christi, TX: Mike Byrnes and Associates. ISBN 978-0962168765.
  • Mittendorf, John. 1998. Truck Company Operations. Saddle Brook, NJ: Fire Engineering. ISBN 0912212640.

External links

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