Caterpillar 797B

The Caterpillar 797B is an off-highway, ultra class, two-axle, mechanical powertrain haul truck developed and manufactured by Caterpillar Inc. in the United States specifically for high production mining and heavy-duty construction applications world-wide.[1] The 797B is the second generation of the 797 series. The 797B was introduced to the public in spring of 2002 and first entered service with a customer in October, 2002.[2] The 797B remained in production until December, 2009 when Caterpillar started full production of the 797B's successor, the 797F.[3] While it was in production, the 797B was Caterpillar's largest, highest payload capacity haul truck model.

Caterpillar 797B
Overview
Manufacturer	Caterpillar Inc.
Production	Spring 2002 - December 2009
Assembly	North America
Body and chassis
Class	Ultra
Body style	2-door Dump
Layout	Front-engine, rear-wheel-drive layout
Powertrain
Engine	Caterpillar 7,143 cu in (117 L) 3524B V-12 x 2 (t/c diesel)
Transmission	7-speed planetary gearset mechanical
Dimensions
Wheelbase	23 ft 7 in (7,188 mm)
Length	47 ft 5 in (14,453 mm)
Width	32 ft 0 in (9,754 mm) - overall tire width (fully loaded)
Height	21 ft 6 in (6,553 mm) - to top of ROPS (empty)
Curb weight	1,375,000 lb (623,690 kg)
Chronology
Predecessor	797
Successor	797F

for an overview of the Caterpillar 797 series, see: Caterpillar 797

Improvements

Compared to the first generation 797, the 797B has a larger payload capacity and a more powerful engine. These changes allowed Caterpillar to meet mine operators' needs to increase operational efficiency and reduce costs by increasing the amount of material hauled per trip.[4]

The 797B's increased payload capacity of 380 short tons (345 t) is a 20 short tons (18.1 t) increase over the first generation 797. Caterpillar increased the power output of the Cat 3524B EUI 24-cylinder diesel engine used in the 797 from net 3,211 hp (2,394 kW) to net 3,370 hp (2,513 kW) enabling the 797B to achieve a 42 mph (68 km/h) top speed when transporting a 380 short tons (345 t) load, a two mile per hour increase over the first generation 797.[5]

Powertrain

Unlike its primary competitors which use diesel-electric powertrains, the Caterpillar 797B employs a mechanical drive powertrain.[4] Caterpillar is the only manufacturer of ultra class haul trucks that feature mechanical powertrains; all ultra class haul trucks offered by competitors employ diesel-electric powertrains.

797B engine

A gross 3,550 hp (2,647 kW) [net 3,370 hp (2,513 kW)], twin turbocharged version of the Cat 3524B engine powers the 797B.[6] The power rating of the 3524B engine is valid up to an elevation of 8,500 ft (2,591 m) or 15,000 ft (4,572 m) with a high altitude arrangement.[7]

Transmission

The 797B is equipped with a rear axle mounted, computer controlled, seven speed planetary transmission with an integral lock-up torque converter.[8]

Wheels and tires

The Caterpillar 797B uses six 5,300 kg (11,680 lb) Michelin 59/80R63 XDR radial tires.[9]

797 Series specifications

Caterpillar 797 Series Specifications

Specification	797	797B	797F
Introduction to Service	1999	2002	2008
Nominal Payload Capacity	360 short tons (327 t)	380 short tons (345 t)	400 short tons (363 t)
Gross Machine Operating Weight	1,230,000 lb (557,900 kg)	1,375,000 lb (623,700 kg)	1,375,000 lb (623,700 kg)
Engine Model	3524B High Displacement EUI	Cat 3524B High Displacement EUI	Cat C175-20 ACERT
Engine Arrangement	V-12 x 2	V-12 x 2	V-20
Engine Power	3,211 hp (2,394 kW) net	3,370 hp (2,513 kW) net (SAE J1349)	3,793 hp (2,828 kW) net (SAE J1349)
Top Speed (Loaded)	40 mph (64 km/h)	42 mph (68 km/h)	42 mph (68 km/h)
Overall Height to Top of ROPS (Empty)	23 ft 8 in (7.21 m)	24 ft 11 in (7.59 m)	24 ft 5 in (7.44 m)
Overall Height (Body Raised)	49 ft 3 in (15.01 m)	50 ft 2 in (15.29 m)	51 ft 6 in (15.70 m)
Overall Length	47 ft 7 in (14.50 m)	47 ft 5 in (14.45 m)	49 ft 6 in (15.09 m)
Overall Tire Width (loaded)	30 ft 0 in (9.14 m)	32 ft 0 in (9.75 m)	31 ft 3 in (9.53 m)
Fuel Capacity	1,200 US gal (4,542 l)	1,200 US gal (4,542 l)	1,000 US gal (3,785 l)

See also

• Haul truck

Notes

1. Caterpillar Inc. 2009.
2. Orlemann 2003, p. 319.
3. Caterpillar Inc. 2009a.
4. Mercer 1999, p. 1.
5. Caterpillar Inc. 2003, p. 19.
6. Caterpillar Inc. 2003, p. 1.
7. Caterpillar Inc. 2003, p. 4.
8. Caterpillar Inc. 2003, p. 5.
9. Manufacture Française des Pneumatiques Michelin 2007, p. 15.

References

• "Caterpillar 797B Mining Truck Product Brochure AEHQ5511" (PDF). cat.com. Caterpillar Inc. December 2003. Archived from the original (PDF) on 2009-10-28. Retrieved 2009-10-28. ... Net Power - Cat 3,370 hp....Nominal Payload Capacity 380 tons ...
• "Release Number: 231PR09 - Caterpillar Moves Forward with New Large Mining Trucks" (Press release). Caterpillar Inc. July 2009. Archived from the original (Microsoft Word 97-2003 Document) on 2009-10-21. Retrieved 2009-10-21. ... go into full production...late this year.
• "Off-Highway Trucks from Caterpillar". cat.com. Caterpillar Inc. Archived from the original on 2009-10-21. Retrieved 2009-10-21. Developed specifically for high production mining and heavy-duty construction applications ...
• Orlemann, Eric C. (2003). Steve Gansen (ed.). The Caterpillar Century. United States of America: Motorbook International. ISBN 0-7603-1882-4. Retrieved 2009-10-27.
• Mercer, Mike (June 1999). "A look at Cat's new 797 haul truck - Caterpillar Inc". Diesel Progress North American Edition. CBS Interactive Inc. Retrieved 2009-10-27. Caterpillar designed the truck in response to mining companies seeking a means to reduce cost per ton ...
• "Michelin Factbook - 2007 Edition". michelin.com. Manufacture Française des Pneumatiques Michelin. 2007. Archived from the original (Shockwave Flash Presentation) on 2009-10-27. Retrieved 2009-10-27. 59/80 R 63 Michelin XDR Diameter: 4,028 meters...Weight: 5,300 kg ...

External links

• Caterpillar 797B Mining Truck Product Brochure AEHQ5511 (PDF)
• Product Safety > Off-Highway Tractors and Trucks - Caterpillar Inc.
• Viewpoint - Perspectives on Modern Mining - Caterpillar Inc.