Unit Rig
Unit Rig was a manufacturer of haul trucks, sold under the brand name Lectra Haul.
History
Unit Rig was founded in 1935 by Hugh S. Chancey and two partners, Jerry R. Underwood and William C. Guier, who formed a partnership to build a rotary drill rig for oil field work that was more mobile than existing designs. The group based the company in Tulsa, Oklahoma. By 1947, the partnership between the men was beginning to break down when Underwood died, leaving Chancey and Guier as the remaining partners. Guier eventually took control of Unit Rig and in 1951 sold it to Kenneth W. Davis, who already had several oil-field related businesses under the parent company name of Kendavis Industries International.
During the 1950s, Unit Rig began to diversify its products away from the limited oil-field products and looked towards mining products to utilize their manufacturing facilities. R. G. LeTourneau had already adapted compact electric drive wheels to construction machinery with great success, prompting Unit Rig to investigate the possibility of building a truck and finding a suitable client to take the finished machine.
By 1960, the M-64 prototype truck was completed using General Electric drive systems and featuring special Goodyear low-pressure tires for the suspension. This truck was not a success; however, Unit Rig went on to be a very successful maker of off-highway dump trucks sold under the brand name of Lectra Haul (due to their electric drive system).
Lectra Haul was eventually sold to Terex then to Bucyrus Erie, who were taken over by Caterpillar Inc. around June 2011. Some Lectra Haul trucks are still sold alongside Caterpillar's own trucks but are branded as Unit Rig.
Products
Early models
- M64
- M85 Kennecott Copper Co., Chino Mines, Santa Rita, NM received the first three M85s produced, serial numbers 52, 53, and 54. Serial #51 was their factory prototype.
- M100
- M120
- M200 (The first 200 tonne capacity truck with two axles)
Second generation
- MK24
- MK30: Became MT3000
- MK33: Became MT3300
- MK36
- MT1900: Upgraded to MT2050, then MT2120, then became MT4000
Third generation (square appearance)
- MT3000
- MT3300
- MT3600
- MT3700
- MT4000
Fourth generation (rounded appearance)
Sold as Lectra Haul, Terex, Bucyrus and now badged Unit Rig under Caterpillar ownership
- MT2700
- MT3000
- MT3300
- MT3600
- MT3700
- MT4400
- MT5500
- Bucyrus MT6300AC: 400 ton class truck
Coal haulers
- BD145: Became BD30 Unitized bottom dump hauler
- BD160
- BD180
- BD240/270
See also
References
- Orlemann, Eric (2012). Haulpak and Lectra Haul: The World's Greatest Off-Highway Earthmoving Trucks. Wisconsin: Icongrafix. ISBN 1583882928.