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64-401: The J47's greatest advantage, as advertised, was its array of features which were unavailable and unprecedented in any other engine. It was advertised as an 'all-weather engine' due to its anti-icing systems which allowed it to perform at high altitudes and extreme temperatures where other aircraft's performance suffered. Its development began without an explicit need for it, although this design

128-433: A dumping truck , dump trailer , dumper trailer , dump lorry or dumper lorry or a dumper for short, is used for transporting materials (such as dirt , gravel , or demolition waste ) for construction as well as coal . A typical dump truck is equipped with an open-box bed, which is hinged at the rear and equipped with hydraulic rams to lift the front, allowing the material in the bed to be deposited ("dumped") on

192-455: A hose , and released to agitate the water. All chemical deicers share a common working mechanism: they chemically prevent water molecules from binding above a certain temperature that depends on the concentration. This temperature is below 0 °C, the freezing point of pure water ( freezing point depression ). Sometimes, there is an exothermic dissolution reaction that allows for an even stronger melting power. The following lists contains

256-415: A 2-axle tractor pulling one single-axle semi-trailer and an additional full trailer (or two full trailers in the case of triples). These dump trucks allow the driver to lay material in windrows without leaving the cab or stopping the truck. The main disadvantage is the difficulty in backing double and triple units. The specific type of dump truck used in any specific country is likely to be closely keyed to

320-558: A heat exchanger that was part of the Heat Transfer Reactor Experiment (HTRE) reactor. The X-39 was successfully operated in conjunction with three different reactors, the HTRE-1, HTRE-2 and HTRE-3. Had the program not been cancelled, these engines would have been used to power the proposed Convair X-6 . Data from Related development Comparable engines Related lists Deicing Deicing

384-635: A result. More recent snowmelters use other salts, such as calcium chloride and magnesium chloride , which not only depress the freezing point of water to a much lower temperature, but also produce an exothermic reaction . They are somewhat safer for sidewalks , but excess should still be removed. More recently, organic compounds have been developed that reduce the environmental issues connected with salts and have longer residual effects when spread on roadways, usually in conjunction with salt brines or solids. These compounds are often generated as byproducts of agricultural operations such as sugar beet refining or

448-479: A separate trailer with a movable cargo container, which can also be loaded with construction aggregate , gravel , sand , asphalt , klinkers, snow, wood chips, triple mix , etc. The second aggregate container on the trailer ("B" box), is powered by an electric motor, a pneumatic motor or a hydraulic line. It rolls on small wheels, riding on rails from the trailer's frame into the empty main dump container ("A" box). This maximizes payload capacity without sacrificing

512-469: A special permit in certain American states. As of 2007 , a triple transfer costs a contractor about $ 105 an hour, while a A/B configuration costs about $ 85 per hour. Transfer dump trucks typically haul between 26 and 27 short tons (23.6 and 24.5  t ; 23.2 and 24.1 long tons ) of aggregate per load, each truck is capable of 3–5 loads per day, generally speaking. A truck and pup is very similar to

576-410: A specific task in the construction material supply chain. A standard dump truck is a truck chassis with a dump body mounted to the frame . The bed is raised by a vertical hydraulic ram mounted under the front of the body (known as a front post hoist configuration), or a horizontal hydraulic ram and lever arrangement between the frame rails (known as an underbody hoist configuration), and the back of

640-467: A stabilizer) below the box, between the chassis rails, to stabilize the load in the raised position. Frame and Frameless end dump truck Depending on the structure, semi trailer end dump truck can also be divided into frame trailer and frameless trailer. The main difference between them is the different structure. The frame dump trailer has a large beam that runs along the bottom of the trailer to support it. The frameless dump trailer has no frame under

704-425: A transfer dump. It consists of a standard dump truck pulling a dump trailer. The pup trailer, unlike the transfer, has its own hydraulic ram and is capable of self-unloading. A super dump is a straight dump truck equipped with a trailing axle, a liftable, load-bearing axle rated as high as 13,000 pounds (5,897 kg). Trailing 11 to 13 feet (3.35 to 3.96 m) behind the rear tandem, the trailing axle stretches

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768-418: Is 40 short tons (36.3  t ; 35.7 long tons ) throughout the country, except for specific bridges with lower limits. Individual states, in some instances, are allowed to authorize trucks up to 52.5 short tons (47.6 t; 46.9 long tons). Most states that do so require that the trucks be very long, to spread the weight over more distance. It is in this context that double and triple bottoms are found within

832-416: Is a (commonly) 3-axle tractor pulling a 2-axle trailer with a clam shell type dump gate in the belly of the trailer. The key advantage of a semi bottom dump is its ability to lay material in a windrow , a linear heap. In addition, a semi bottom dump is maneuverable in reverse, unlike the double and triple trailer configurations described below. These trailers may be found either of the windrow type shown in

896-540: Is a significant pollutant in waterways and wildlife, as it degrades to ammonia after application, and it has largely been phased out at U.S. airports. In 2012 the U.S. Environmental Protection Agency (EPA) prohibited use of urea-based deicers at most commercial airports. Water agitators are electric motors put under water that propel up warmer water and agitate the surface with it to deice aquatic structures on rivers and lakes in freezing temperatures. There are also agitator bubblers that use compressed air , run through

960-429: Is an all-wheel-drive, off-road dump truck. It has a hinge between the cab and the dump box but is distinct from a semi-trailer truck in that the power unit is a permanent fixture, not a separable vehicle. Steering is accomplished via hydraulic cylinders that pivot the entire tractor in relation to the trailer, rather than rack and pinion steering on the front axle as in a conventional dump truck. By this way of steering,

1024-464: Is normally used, as it is inexpensive and readily available in large quantities. However, since salt water still freezes at −18 °C (0 °F), it is of no help when the temperature falls below this point. It also has a tendency to cause corrosion , rusting the steel used in most vehicles and the rebar in concrete bridges. Depending on the concentration, it can be toxic to some plants and animals, and some urban areas have moved away from it as

1088-422: Is not generally used by the mining industry, or by the manufacturers that build these machines. The more appropriate U.S. term for this strictly off-road vehicle is " haul truck " and the equivalent European term is "dumper". Haul trucks are used in large surface mines and quarries. They have a rigid frame and conventional steering with drive at the rear wheel. As of late 2013, the largest ever production haul truck

1152-516: Is primarily the brakes , suspension and couplers that require heaters for deicing. On rails it is primarily the switches that are sensitive to ice. High-powered electrical heaters prevent ice formation and rapidly melt any ice that forms. The heaters are preferably made of PTC material, for example PTC rubber , to avoid overheating and potentially destroying the heaters. These heaters are self-limiting and require no regulating electronics; they cannot overheat and require no overheat protection. On

1216-657: Is the 450 metric ton BelAZ 75710 , followed by the Liebherr T 282B , the Bucyrus MT6300AC and the Caterpillar 797F , which each have payload capacities of up to 400 short tons (363  t ; 357 long tons ). The previous record holder being the Canadian-built Terex 33-19 "Titan" , having held the record for over 25 years. Most large-size haul trucks employ Diesel-electric powertrains, using

1280-458: Is the process of removing snow , ice or frost from a surface. Anti-icing is the application of chemicals that not only deice but also remain on a surface and continue to delay the reformation of ice for a certain period of time, or prevent adhesion of ice to make mechanical removal easier. Deicing can be accomplished by mechanical methods (scraping, pushing); through the application of heat ; by use of dry or liquid chemicals designed to lower

1344-450: Is to use high-strength plates. Under the premise of ensuring the strength of the car body, the thickness of the plate is reduced by about 20%, and the self-weight of the car is reduced by about 1 ton, which effectively improves the utilization factor of the load mass. 3. Strong carrying capacity. Using high-strength steel plate, high yield strength, better impact resistance and fatigue resistance. For users of ore transportation, it can reduce

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1408-514: The distillation process that produces ethanol . Other organic compounds are wood ash and a deicing salt called calcium magnesium acetate made from roadside grass or even kitchen waste. Additionally, mixing common rock salt with some of the organic compounds and magnesium chloride results in spreadable materials that are both effective to much colder temperatures (−34 °C (−29 °F)) as well as at lower overall rates of spreading per unit area. Solar road systems have been used to maintain

1472-498: The freezing point of water (various salts or brines , alcohols , glycols ); or by a combination of these different techniques. In 2013, an estimated 14 million tons of salt were used for deicing roads in North America. Deicing of roads has traditionally been done with salt , spread by snowplows or dump trucks designed to spread it, often mixed with sand and gravel , on slick roads. Sodium chloride (rock salt)

1536-457: The water column are consumed when microbial populations decompose propylene glycol. Some airports recycle used deicing fluid, separating water and solid contaminants, enabling reuse of the fluid in other applications. Other airports have an on-site wastewater treatment facility, and/or send collected fluid to a municipal sewage treatment plant or a commercial wastewater treatment facility. Dump truck A dump truck , known also as

1600-485: The Diesel engine to drive an AC alternator or DC generator that sends electric power to electric motors at each rear wheel. The Caterpillar 797 is unique for its size, as it employs a Diesel engine to power a mechanical powertrain, typical of most road-going vehicles and intermediary size haul trucks. Other major manufacturers of haul trucks include SANY, XCMG, Hitachi, Komatsu, DAC, Terex, and BelAZ. An articulated dumper

1664-475: The UK) does the same job, but lifts, lowers, and dumps the container with a boom arrangement instead of a cable and hoist. Off-highway dump trucks are heavy construction equipment and share little resemblance to highway dump trucks. Bigger off-highway dump trucks are used strictly off-road for mining and heavy dirt hauling jobs. There are two primary forms: rigid frame and articulating frame. The term "dump" truck

1728-469: The United States. Bumper Pull personal and commercial Dump Trailers come in a variety of sizes from smaller 6x10 7,000 GVWR models to larger 7x16 High Side 14,000 GVWR models. Dump trailers come with a range of options and features such as tarp kits, high side options, dump/spread/swing gates, remote control, scissor, telescop, dual or single cylinder lifts, and metal locking toolboxes. They offer

1792-410: The bed is hinged at the back of the truck. The tailgate (sometimes referred to as an end gate) can be configured to swing up on top hinges (and sometimes also to fold down on lower hinges) or it can be configured in the "High Lift Tailgate" format wherein pneumatic or hydraulic rams lift the gate open and up above the dump body. Some bodies, typically for hauling grain, have swing-out doors for entering

1856-479: The box and a metering gate/chute in the center for a more controlled dumping. In the United States most standard dump trucks have one front steering axle and one (4x2 4-wheeler ) or two (6x4 6-wheeler ) rear axles which typically have dual wheels on each side. Tandem rear axles are almost always powered, front steering axles are also sometimes powered (4x4, 6x6). Unpowered axles are sometimes used to support extra weight. Most unpowered rear axles can be raised off

1920-412: The box. From the 1930s Euclid , International-Harvester and Mack contributed to ongoing development. Mack modified its existing trucks with varying success. In 1934 Euclid became the first manufacturer in the world to successfully produce a dedicated off-highway truck. Today, virtually all dump trucks operate by hydraulics and they come in a variety of configurations each designed to accomplish

1984-415: The characteristics of impact resistance, alternating stress resistance, corrosion resistance and so on. 1. Cleaner unloading U-shaped dump truck, there is no dead angle at the corners of the cargo box, it is not easy to stick to the box when unloading, and the unloading is cleaner. 2. Lightweight The U-shaped cargo box reduces its own weight through structural optimization. Now the most common U-shaped dump

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2048-479: The damage of ore to the container. 4. Low center of gravity The U-shaped structure has a lower center of gravity, which makes the ride more stable, especially when cornering, and avoids spilling cargo. 5. Save tires The U-shaped cargo box can keep the cargo in the center, and the tires on both sides are more evenly stressed, which is beneficial to improve the life of the tires. Dump trucks are normally built for some amount of off-road or construction site driving; as

2112-585: The driver is protected by the chassis and height of the driver's seat, bumpers are either placed high or omitted for added ground clearance. The disadvantage is that in a collision with a standard car, the entire motor section or luggage compartment goes under the truck. Thus, the passengers in the car could be more severely injured than would be common in a collision with another car. Several countries have made rules that new trucks should have bumpers approximately 40 cm (16 in) above ground in order to protect other drivers. There are also rules about how long

2176-500: The dumpsite, after it has been dumped the empty container is taken and placed to be loaded or stored. The hoist is raised and the container slides down the subframe so the rear is on the ground. The container has rollers on the rear and can be moved forward or back until the front of it is lowered onto the ground. The containers are usually open-topped boxes used for rubble and building debris, but rubbish compactor containers are also carried. A newer hook-lift system ("roller container" in

2240-572: The engine include: In the 1950s, interest in the development of nuclear-powered aircraft led GE to experiment with two nuclear-powered gas turbine designs, one based on the J47, and another new and much larger engine called the X211 . The design based on the J47 became the X39 program. This system consisted of two modified J47 engines which, instead of combusting jet fuel, received their heated, compressed air from

2304-601: The engine led to it becoming the most produced jet engine in aviation history, and established GE Aviation as a worldwide leader in jet propulsion. Overhaul life for the J47 ranged from 15 hours (in 1948) to a theoretical 1,200 hours (625 achievable in practice) in 1956. For example, the J47-GE-23 was rated to run 225 hours time between overhauls . As installed on the F-86F, it experienced one in-flight shutdown every 33,000 hours in 1955 and 1956. Ground-based vehicles that used

2368-636: The engine was first tested. The engine featured an electronically controlled afterburner , a system that dumped additional fuel into the combustor pipe 'behind' the engine, reheating the exhaust and producing significantly more thrust, although with greatly reduced efficiency and high fuel burn rates. The engine production process in the Lockland facility (renamed to the Evendale facility) utilized vertical engine assembly to ensure compressor rotor balance and stability. The technological jump provided by

2432-653: The farms of late 19th century western Europe. Thornycroft developed a steam dust-cart in 1896 with a tipper mechanism. The first motorized dump trucks in the United States were developed by small equipment companies such as The Fruehauf Trailer Corporation , Galion Buggy Co. and Lauth-Juergens among many others around 1910. Hydraulic dump beds were introduced by Wood Hoist Co. shortly after. Such companies flourished during World War I due to massive wartime demand. August Fruehauf had obtained military contracts for his semi-trailer, invented in 1914 and later created

2496-489: The following approaches: Deicing operations for airport pavement ( runways , taxiways , aprons , taxiway bridges ) may involve several types of liquid and solid chemical products, including propylene glycol , ethylene glycol and other organic compounds. Chloride-based compounds (e.g. salt ) are not used at airports, due to their corrosive effect on aircraft and other equipment. Urea mixtures have also been used for pavement deicing, due to their low cost. However, urea

2560-459: The ground behind the truck at the site of delivery. In the UK, Australia, South Africa and India the term applies to off-road construction plants only and the road vehicle is known as a tip lorry , tipper lorry (UK, India), tipper truck , tip truck , tip trailer or tipper trailer or simply a tipper (Australia, New Zealand, South Africa). The dump truck is thought to have been first conceived in

2624-450: The ground to minimize wear when the truck is empty or lightly loaded, and are commonly called "lift axles". European Union heavy trucks often have two steering axles. Dump truck configurations are two, three, and four axles. The four-axle eight wheeler has two steering axles at the front and two powered axles at the rear and is limited to 32 metric tons (35 short tons ; 31 long tons ) gross weight in most EU countries. The largest of

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2688-680: The ground, when there are freezing conditions and precipitation , deicing an aircraft is commonly practiced. Frozen contaminants interfere with the aerodynamic properties of the vehicle. Furthermore, dislodged ice can damage the engines. Ground deicing methods include: Ice can build up on aircraft in flight due to atmospheric conditions, causing potential degradation of flight performance. Large commercial aircraft almost always have in-flight ice protections systems to shed ice buildup and prevent reformation. Ice protection systems are becoming increasingly common in smaller general aviation aircraft as well. Ice protection systems typically use one or more of

2752-564: The hydraulic hoist . In the US a typical semi end dump has a 3-axle tractor pulling a 2-axle trailer with dual tires, in the EU trailers often have 3 axles and single tires. The key advantage of a semi end dump is a large payload. A key disadvantage is that they are very unstable when raised in the dumping position limiting their use in many applications where the dumping location is uneven or off level. Some end dumps make use of an articulated arm (known as

2816-440: The load or construction of the truck can go beyond the rear bumper to prevent cars that rear-end the truck from going under it. Another safety consideration is the leveling of the truck before unloading. If the truck is not parked on relatively horizontal ground, the sudden change of weight and balance due to lifting of the body and dumping of the material can cause the truck to slide, or even to tip over. The live bottom trailer

2880-503: The maneuverability of the standard dump truck. Transfer dump trucks are typically seen in the western United States due to the peculiar weight restrictions on highways there. Another configuration is called a triple transfer train, consisting of a "B" and "C" box. These are common on Nevada and Utah Highways, but not in California. Depending on the axle arrangement, a triple transfer can haul up to 129,000 kilograms (284,000 pounds) with

2944-506: The most-commonly used deicing chemicals and their typical chemical formula . Deicing salts such as sodium chloride or calcium chloride leach into natural waters, strongly affecting their salinity. Ethylene glycol and propylene glycol are known to exert high levels of biochemical oxygen demand (BOD) during degradation in surface waters. This process can adversely affect aquatic life by consuming oxygen needed by aquatic organisms for survival. Large quantities of dissolved oxygen (DO) in

3008-448: The outer "bridge" measurement—the distance between the first and last axles—to the maximum overall length allowed. This increases the gross weight allowed under the federal bridge formula, which sets standards for truck size and weight. Depending on the vehicle length and axle configuration, Superdumps can be rated as high as 80,000 pounds (36,287 kg) GVW and carry 26 short tons (23.6  t ; 23.2 long tons ) of payload or more. When

3072-512: The partner vehicle, the semi-truck for use in World War I. After the war, Fruehauf introduced hydraulics in his trailers. They offered hydraulic lift gates, hydraulic winches and a dump trailer for sales in the early 1920s. Fruehauf became the premier supplier of dump trailers and their famed "bathtub dump" was considered to be the best by heavy haulers, road and mining construction firms. Companies like Galion Buggy Co. continued to grow after

3136-404: The perfect solution for a variety of applications, including roofing, rock and mulch delivery, general contractors, skid steer grading, trash out, and recycling. A side dump truck (SDT) consists of a 3-axle tractor pulling a 2-axle semi-trailer. It has hydraulic rams that tilt the dump body onto its side, spilling the material to either the left or right side of the trailer. The key advantages of

3200-449: The photo or may be of the cross spread type, with the gate opening front to rear instead of left and right. The cross spread type gate will actually spread the cereal grains fairly and evenly from the width of the trailer. By comparison, the windrow-type gate leaves a pile in the middle. The cross spread type gate, on the other hand, tends to jam and may not work very well with coarse materials. Double and triple bottom dumps consist of

3264-412: The placement of ballast to weigh the truck down or to hold sodium or calcium chloride salts for spreading on snow and ice-covered surfaces. Plowing is severe service and needs heavy-duty trucks. A Roll-off has a hoist and subframe, but no body, it carries removable containers. The container is loaded on the ground, then pulled onto the back of the truck with a winch and cable. The truck goes to

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3328-404: The side dump are that it allows rapid unloading and can carry more weight in the western United States. In addition, it is almost immune to upset (tipping over) while dumping, unlike the semi end dumps which are very prone to tipping over. It is, however, highly likely that a side dump trailer will tip over if dumping is stopped prematurely. Also, when dumping loose materials or cobble sized stone,

3392-462: The side dump can become stuck if the pile becomes wide enough to cover too much of the trailer's wheels. Trailers that dump at the appropriate angle (50° for example) avoid the problem of the dumped load fouling the path of the trailer wheels by dumping their loads further to the side of the truck, in some cases leaving sufficient clearance to walk between the dumped load and the trailer. Many winter service vehicles are based on dump trucks, to allow

3456-422: The standard European dump trucks is commonly called a "centipede" and has seven axles. The front axle is the steering axle, the rear two axles are powered, and the remaining four are lift axles. The shorter wheelbase of a standard dump truck often makes it more maneuverable than the higher capacity semi-trailer dump trucks . A semi end dump is a tractor-trailer combination wherein the trailer itself contains

3520-419: The surface of roads above the freezing point of water. An array of pipes embedded in the road surface is used to collect solar energy in summer, transfer the heat to thermal banks and return the heat to the road in winter to maintain the surface above 0 °C (32 °F). This automated form of renewable energy collection, storage and delivery avoids the environmental issues of using chemical contaminants. It

3584-401: The trailer but has ribs that go around the body for support and the top rail of the trailer serves as a suspension bridge for support. The difference in structure also brings with it a difference in weight. Frame dump trailers are heavier. For the same length, a frame dump trailer weighs around 5 ton more than a frameless dump trailer. A transfer dump truck is a standard dump truck pulling

3648-422: The trailer's wheels follow the same path as the front wheels. Together with all-wheel drive and low center of gravity, it is highly adaptable to rough terrain. Major manufacturers include Volvo CE, Terex, John Deere, and Caterpillar. U-shaped dump trucks, also known as tub-body trucks, is used to transport construction waste, it is made of high-strength super wear-resistant special steel plate directly bent, and has

3712-466: The truck is empty or ready to offload, the trailing axle toggles up off the road surface on two hydraulic arms to clear the rear of the vehicle. Truck owners call their trailing axle-equipped trucks Superdumps because they far exceed the payload , productivity, and return on investment of a conventional dump truck. The Superdump and trailing axle concept were developed by Strong Industries of Houston, Texas. A semi bottom dump, bottom hopper, or belly dump

3776-552: The war by manufacturing a number of express bodies and some smaller dump bodies that could be easily installed on either stock or converted (heavy-duty suspension and drivetrain) Model T chassis prior to 1920. Galion and Wood Mfg. Co. built all of the dump bodies offered by Ford on their heavy-duty AA and BB chassis during the 1930s. Galion (now Galion Godwin Truck Body Co.) is the oldest known truck body manufacturer still in operation today. The first known Canadian dump truck

3840-400: The weight and axle limitations of that jurisdiction. Rock, dirt, and other types of materials commonly hauled in trucks of this type are quite heavy, and almost any style of truck can be easily overloaded. Because of that, this type of truck is frequently configured to take advantage of local weight limitations to maximize the cargo. For example, within the United States, the maximum weight limit

3904-491: Was described by Flight magazine in 1948 as the most widely used American-conceived turbojet. The turbojet featured a revolutionary anti-icing system where hollow frame struts allowed heated airflow to pass through from the compressor , allowing fighter jets equipped with the engine to function at high altitudes, and in cold conditions such as the top of Mount Washington in New Hampshire's White Mountains , where

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3968-478: Was developed in Saint John, New Brunswick , when Robert T. Mawhinney attached a dump box to a flatbed truck in 1920. The lifting device was a winch attached to a cable that fed over sheave ( pulley ) mounted on a mast behind the cab. The cable was connected to the lower front end of the wooden dump box which was attached by a pivot at the back of the truck frame. The operator turned a crank to raise and lower

4032-590: Was quickly purchased by the military for its many potential benefits. In 1978, J47s were formally withdrawn from active military duty when the Air National Guard retired the jet-boosted KC-97Js. Despite this, these engines are still extensively utilized in F-86 Sabre jets owned by civilians, making them a common sight at air shows. The J47 design used experience from the TG-180/J35 engine which

4096-497: Was suggested in 2012 that superhydrophobic surfaces capable of repelling water can also be used to prevent ice accumulation leading to icephobicity . However, not every superhydrophobic surface is icephobic and the method is still under development. Trains and rail switches in Arctic regions can have significant problems with snow and ice build up. They need a constant heat source on cold days to ensure functionality. On trains it

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