Haul truck

Description

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 40 short tons (36.3 t; 35.7 long tons) to nearly 500 short tons (454 t; 446 long tons).

An example on the smaller end is the Caterpillar 775 (rated at 70 short tons [62 long tons]). Quarry operations (which produce payloads that have value) are typically employ smaller trucks than mining operations (such as removing undesirable overburden, an expense).

Haul trucks can generally be distinguished from standard dump trucks by:

• Being far too large to travel legally on public roads
• Having a dump body made of exceptionally strong steel plate that extends over the cab to protect it, angled upright at its end (or entirely) to aid in dumping; some are heated by exhaust gases to prevent loads from sticking or freezing to the bed;
• Having a driver's cab narrower than its body;
• No axle suspension;
• Limited speed and operating range;
• Special off-road only tires;
• A ratio of dead weight to payload not exceeding 1:1.6

Most large haul trucks use some form of traction motors coupled to regenerative brakings for power, braking, or both.

Haul trucks are classified by:

• Type of unloading (dump or rear-eject);
• Direction of discharge (side, rear);
• Type of body (hopper, platform, sliding hopper, sliding platform).