Haul truck

Haul trucks are off-highway, rigid dump trucks specifically engineered for use in high-production mining and heavy-duty construction environments. Haul trucks are also used for transporting construction equipment from job site to job site. Some are multi-axle in order to support the equipment that is being hauled. Most haul trucks have a two-axle design, but two well-known models from the 1970s, the 350T Terex Titan and 235T Wabco 3200/B, had three axles. Haul truck capacities range from to . Large quarry-sized trucks range from . A good example of this is the Caterpillar 775 (rated at ). Quarry operations are typically smaller than, say, a gold/copper mine, and require smaller trucks. As a rule, these dump trucks can be distinguished from other trucks (in particular, dump truck) by the following features: the tipper body is made of very strong steel plate; its front is extended above the driver's cab to protect the cab; the entire bottom, or rear of it, points upward; in some cases the driver's cab is only half the width of the truck; no axle suspension; powerful brakes; limited speed and operating range; special tires used for driving on the ground; due to the robust design the ratio of dead weight to payload does not exceed 1:1.6 the body can be heated by exhaust gases to prevent the transported material from sticking or freezing. Dump trucks are classified by: type of unloading (inclined or forced); the direction of discharge (side, rear); type of body (hopper, platform, sliding hopper, sliding platform). The largest, highest-payload-capacity haul trucks are referred to as ultra class trucks. The ultra class includes all haul trucks with a payload capacity of or greater. , the BelAZ 75710 has the highest payload capacity, . A rear-eject configuration is an alternative haul truck body style. Instead of lifting the bed vertically, the hydraulic cylinder pushes a ram-face horizontally through the body to eject the hauled load. Rear-eject dump vehicles were first introduced in the 1980s by LeRoy Hagenbuch, P.E.