Haul truck

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. [1] Haul truck capacities range from 40 short tons (36 long tons; 36 t) to 496 short tons (443 long tons; 450 t).

Large quarry-sized trucks range from 40 to 100 short tons (36 to 89 long tons; 36 to 91 t). A good example of this is the Caterpillar 775 (rated at 70 short tons [62 long tons; 64 t]).[2] 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).

Liebherr T 282B ultra class haul truck

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 300 short tons (270 long tons; 270 t) or greater.[3] As of October 2013, the BelAZ 75710 has the highest payload capacity, 450 metric tons (440 long tons; 500 short tons).[4]

A rear-eject Komatsu HM400-2

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.[5]

Rear-eject dump vehicles were first introduced in the 1980s by LeRoy Hagenbuch, P.E. of Philippi-Hagenbuch, Inc.,[6] for a refuse hauling application in New York City. They were designed to work on Volvo BM truck chassis. While the functionality of the ejector bodies worked well, they were prone to maintenance issues and not replicated until the 1990s. The next documented ejector bodies were developed by DDT, a UK truck manufacturer.[7] A variation using steel chains instead of a hydraulic ram was introduced by Bell, but did not become popular.[8]

Caterpillar Inc. began offering a rear-eject option using technology originally designed for its scrapers after one of its contractors successfully converted a few CAT D400 models. The new design, installed on the company's D400E model, was less likely to jam in cold weather.[8] CAT later began manufacturing a standard R.E. body for its 730, 740, and 740B articulating haul-truck series.[9]

Philippi-Hagenbuch, a company specializing in truck body design, developed its own mechanism for its rear-eject bodies, and has patented its design in the US, Europe and Australia.[5] The company customizes Rear-Eject bodies or trailers for several manufacturers' off-highway vehicles; including both rigid and articulating varieties.[10]

As of 2014 Caterpillar Inc. and Philippi-Hagenbuch, Inc. are continuing to manufacture Rear-Eject bodies for off-highway applications,[5] each using its own design of mechanism.

Look up long haul in Wiktionary, the free dictionary.

• Articulated hauler
• Dumper
• Haul road
• Rear-eject haul truck bodies
• Unit Rig