The Caterpillar 797 is a series of
off-highway,
ultra class, two-
axle
An axle or axletree is a central shaft for a rotation, rotating wheel and axle, wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In ...
, mechanical
powertrain
In a motor vehicle, the powertrain comprises the main components that generate engine power, power and deliver that power to the road surface, water, or air. This includes the internal combustion engine, engine, transmission (mechanics), trans ...
haul truck
Haul trucks are off-road, heavy-duty dump trucks specifically engineered for use in high-production mining and exceptionally demanding construction environments. Most are dual axle; at least two examples of tri-axles were made in the 1970s. Hau ...
s developed and manufactured in the United States by
Caterpillar Inc.
Caterpillar Inc., also known as Cat, is an American construction, mining and other engineering equipment manufacturer. The company is the world's largest manufacturer of construction equipment.
In 2018, Caterpillar was ranked number 73 on the ' ...
specifically for high-production
mining
Mining is the Resource extraction, extraction of valuable geological materials and minerals from the surface of the Earth. Mining is required to obtain most materials that cannot be grown through agriculture, agricultural processes, or feasib ...
and heavy
construction
Construction are processes involved in delivering buildings, infrastructure, industrial facilities, and associated activities through to the end of their life. It typically starts with planning, financing, and design that continues until the a ...
applications worldwide.
In production since 1998, the 797 series represents Caterpillar’s largest, highest capacity haul trucks.
The current, third-generation model, the 797F, offers one of the largest haul truck
payload
Payload is the object or the entity that is being carried by an aircraft or launch vehicle. Sometimes payload also refers to the carrying capacity of an aircraft or launch vehicle, usually measured in terms of weight. Depending on the nature of t ...
capacities in the world, up to and has the highest payload capacity among mechanical drive haul trucks.
Initial development
In 1997, Caterpillar decided to begin the development of a payload capacity haul truck to meet the demand from large-scale mine operators wanting to reduce operating costs at mines using 80 to 90 short tons (73 to 82 t) per pass
shovels
A shovel is a tool used for digging, lifting, and moving bulk materials, such as soil, coal, gravel, snow, sand, or ore. Most shovels are hand tools consisting of a broad blade fixed to a medium-length handle. Shovel blades are usually made of ...
.
Engineer
Engineers, as practitioners of engineering, are professionals who Invention, invent, design, build, maintain and test machines, complex systems, structures, gadgets and materials. They aim to fulfill functional objectives and requirements while ...
s at Caterpillar's Mining & Construction Equipment Division in
Decatur, Illinois
Decatur ( ) is the largest city in Macon County, Illinois, United States, and its county seat. The city was founded in 1829 and is situated along the Sangamon River and Lake Decatur in Central Illinois. As of the 2020 United States census, 2020 ...
, created a new design for the 797 using
computer-aided design
Computer-aided design (CAD) is the use of computers (or ) to aid in the creation, modification, analysis, or optimization of a design. This software is used to increase the productivity of the designer, improve the quality of design, improve c ...
technology. This was the first time CAD tools had been used extensively to design a Caterpillar truck.
[
]
797 (1998–2002)
Caterpillar first unveiled a completed 797 on September 29, 1998, at its assembly plant in Decatur, Illinois. The first two 797s produced were transported to Caterpillar's Arizona
Arizona is a U.S. state, state in the Southwestern United States, Southwestern region of the United States, sharing the Four Corners region of the western United States with Colorado, New Mexico, and Utah. It also borders Nevada to the nort ...
proving grounds for testing. In the second quarter of 1999, the third and fourth 797s produced were the first to be placed in service with a customer at the Bingham Canyon Mine in Utah
Utah is a landlocked state in the Mountain states, Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to the northea ...
. Caterpillar put 18 additional 797s into service with mine operators worldwide, as production development units.
Caterpillar began marketing the 797 in North America
North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...
in 2000, with full worldwide marketing
Marketing is the act of acquiring, satisfying and retaining customers. It is one of the primary components of Business administration, business management and commerce.
Marketing is usually conducted by the seller, typically a retailer or ma ...
following in 2001. The first generation serial number prefix is 5YW.[
]
797B (2002–2009)
Caterpillar introduced the 797B in the spring of 2002, replacing the first-generation 797. The 797B's increased payload capacity of is a increase over the first generation 797. Caterpillar increased the power output of the Cat 3524B EUI 24-cylinder
A cylinder () has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base.
A cylinder may also be defined as an infinite ...
diesel engine used in the 797 from net to net enabling the 797B to achieve a top speed when transporting a load, a increase over the first generation 797.
The first 797B units entered service with customers in October 2002.
797F (2009–present)
Caterpillar introduced the 797F to the public at MINExpo International in September, 2008. The 797F replaced its predecessor model, the 797B, when the 797F entered full production in late 2009.[
][
] Prior to the introduction of the Caterpillar 797F and the Bucyrus MT6300AC
The Bucyrus MT6300AC is an off-highway, ultra class, two-axle, diesel/ AC electric powertrain haul truck designed and manufactured by Bucyrus International Inc. in the United States. The MT6300AC is Bucyrus' largest, highest payload capacity haul ...
at MINExpo International in September, 2008, the Liebherr T 282B
The Liebherr T 282 series are off-highway, ultra class, rigid frame, two axle, diesel-electric, AC powertrain haul trucks designed and manufactured in the United States by Liebherr Mining Equipment Co.
The Liebherr T 282 series is no longer ...
, introduced in 2004, was the only haul truck with a payload capacity of .
Compared to the 797B, the 797F has a higher payload capacity and a more powerful, more efficient engine. These changes allowed Caterpillar to meet mine operator's needs to increase operational efficiency and reduce costs by increasing the amount of material hauled per trip.
The 797F's increased payload capacity of is a increase over the 797B.[
Caterpillar replaced the gross et Cat 3524B EUI 24-]cylinder
A cylinder () has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base.
A cylinder may also be defined as an infinite ...
diesel engine
The diesel engine, named after the German engineer Rudolf Diesel, is an internal combustion engine in which Combustion, ignition of diesel fuel is caused by the elevated temperature of the air in the cylinder due to Mechanics, mechanical Compr ...
used in the 797B with the gross et Cat C175-20 ACERT 20-cylinder diesel engine, enabling the 797F to maintain the top speed of the 797B while transporting a heavier payload.
Powertrain
The Caterpillar 797 series trucks employ mechanical
Mechanical may refer to:
Machine
* Machine (mechanical), a system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement
* Mechanical calculator, a device used to perform the basic operations o ...
drive powertrain
In a motor vehicle, the powertrain comprises the main components that generate engine power, power and deliver that power to the road surface, water, or air. This includes the internal combustion engine, engine, transmission (mechanics), trans ...
s in contrast to the diesel-electric powertrains of similar haul trucks offered by competitors.[ During initial development in 1997, a diesel-electric powertrain was considered for the 797, but this powertrain configuration was not developed because Caterpillar considered a mechanical drive powertrain more appropriate for market conditions at that time.][
]
797 engine
A gross et Cat 3524B HD EUI 24-cylinder
A cylinder () has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base.
A cylinder may also be defined as an infinite ...
, electronic
Electronic may refer to:
*Electronics, the science of how to control electric energy in semiconductors
* ''Electronics'' (magazine), a defunct American trade journal
*Electronic storage, the storage of data using an electronic device
*Electronic c ...
unit injection, quad single-stage turbocharged
In an internal combustion engine, a turbocharger (also known as a turbo or a turbosupercharger) is a forced induction device that is powered by the flow of exhaust gases. It uses this energy to compress the intake air, forcing more air into the ...
, liquid aftercooled, four-stroke
A four-stroke (also four-cycle) engine is an internal combustion (IC) engine in which the piston completes four separate strokes while turning the crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either directio ...
diesel
Diesel may refer to:
* Diesel engine, an internal combustion engine where ignition is caused by compression
* Diesel fuel, a liquid fuel used in diesel engines
* Diesel locomotive, a railway locomotive in which the prime mover is a diesel engine ...
engine
An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy.
Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ge ...
powers the 797. The Cat 3524B HD engine is a tandem unit consisting of two 12-cylinder Cat 3512B HD engine blocks coupled to operate as a single engine with a combined displacement of 106 liters (6468 cubic inches).
797B engine
A gross et quad turbocharged Caterpillar 3524B engine powers the 797B.[ The power rating of the 3524B is valid up to an ]elevation
The elevation of a geographic location (geography), ''location'' is its height above or below a fixed reference point, most commonly a reference geoid, a mathematical model of the Earth's sea level as an equipotential gravitational equipotenti ...
of or with a high altitude
Altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum (geodesy), datum and a point or object. The exact definition and reference datum varies according to the context (e.g., aviation, geometr ...
arrangement.[
]
797F engine
A gross et Cat C175-20 ACERT single block, 20-cylinder, electronic common rail injection, quad turbocharged, air-to-air aftercooled, four-stroke diesel engine powers the 797F.[ The power rating of the C175-20 is valid up to an elevation of or up to with a high altitude arrangement.]
Transmission
The 797 series haul trucks are equipped with a rear-axle
An axle or axletree is a central shaft for a rotation, rotating wheel and axle, wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In ...
-mounted, computer
A computer is a machine that can be Computer programming, programmed to automatically Execution (computing), carry out sequences of arithmetic or logical operations (''computation''). Modern digital electronic computers can perform generic set ...
-controlled, seven-speed planetary transmission
Transmission or transmit may refer to:
Science and technology
* Power transmission
** Electric power transmission
** Transmission (mechanical device), technology that allows controlled application of power
*** Automatic transmission
*** Manual tra ...
with a separate lock-up torque converter
A torque converter is a device, usually implemented as a type of fluid coupling, that transfers rotating power from a prime mover, like an internal combustion engine, to a rotating driven load. In a vehicle with an automatic transmission, the ...
. Both transmission and torque converter use a common powertrain oil.[
]
Wheels and tires
Each 797 wheel is attached to the axle using 54 - nuts that are torqued to . A size 55/80R63 radial tire
A radial tire (more properly, a radial-ply tire) is a particular design of vehicular tire. In this design, the cord plies are arranged at 90 degrees to the direction of travel, or radially (from the center of the tire). Radial tire constructio ...
was developed by Michelin in conjunction with Caterpillar specifically for the first generation 797. The Caterpillar 797B and 797F run tall, Michelin
Michelin ( , ), in full ("General Company of the Michelin Enterprises P.L.S."), is a French multinational tyre manufacturing company based in Clermont-Ferrand in the Auvergne-Rhône-Alpes '' région'' of France. It is the second largest t ...
59/80R63 XDR. Most first generation 797s have been retrofitted to use the 59/80R63 tires as well. Six tires are required per truck at a cost in 2009 of approximately US$42,500 per tire.
Manufacturing and assembly
Major components of the 797 are manufactured and assembled at seven Caterpillar or supplier facilities located throughout North America, then shipped to the customer site for final assembly by Caterpillar technicians.
The engine is manufactured by Caterpillar in Lafayette, Indiana
Lafayette ( ) is a city in and is the county seat of Tippecanoe County, Indiana, United States, located northwest of Indianapolis and southeast of Chicago. According to the 2020 United States census, 2020 census, the population of Lafayette ...
, and is then shipped to Caterpillar's assembly plant in Decatur, Illinois
Decatur ( ) is the largest city in Macon County, Illinois, United States, and its county seat. The city was founded in 1829 and is situated along the Sangamon River and Lake Decatur in Central Illinois. As of the 2020 United States census, 2020 ...
.
The transmission
Transmission or transmit may refer to:
Science and technology
* Power transmission
** Electric power transmission
** Transmission (mechanical device), technology that allows controlled application of power
*** Automatic transmission
*** Manual tra ...
and torque converter
A torque converter is a device, usually implemented as a type of fluid coupling, that transfers rotating power from a prime mover, like an internal combustion engine, to a rotating driven load. In a vehicle with an automatic transmission, the ...
are manufactured by Caterpillar in East Peoria, Illinois
East Peoria is a city in Tazewell County, Illinois, United States. The population was 22,484 at the 2020 census. East Peoria is part of the Peoria metropolitan area, located across the Illinois River from downtown Peoria. It is home to many Ca ...
, and is then shipped to Caterpillar's assembly plant in Decatur, Illinois
Decatur ( ) is the largest city in Macon County, Illinois, United States, and its county seat. The city was founded in 1829 and is situated along the Sangamon River and Lake Decatur in Central Illinois. As of the 2020 United States census, 2020 ...
.
The axle assemblies are manufactured by Caterpillar in Winston-Salem, North Carolina
Winston-Salem is a city in Forsyth County, North Carolina, United States, and its county seat. At the 2020 United States census, 2020 census, the population was 249,545, making it the List of municipalities in North Carolina, fifth-most populous ...
, and are shipped to the customer site.
The tires are manufactured by Michelin North America at the US7 Earthmover Manufacturing plant in Lexington, South Carolina
Lexington is the most populous town in and the county seat of Lexington County, South Carolina, United States. It is a suburb of the state capital, Columbia, South Carolina, Columbia. The population was 23,568 at the 2020 Census, and it is the ...
, and are shipped to the customer site.
The driver's cab is manufactured by Bergstrom Climate Control Systems' Contract Assembly division in Joliet, Illinois
Joliet ( ) is a city in Will County, Illinois, Will and Kendall County, Illinois, Kendall counties in the U.S. state of Illinois, located southwest of Chicago. It is the county seat of Will County, Illinois, Will County. It had a population of ...
. Each cab is assembled by one person and requires forty hours to complete. The cab is shipped to the customer site.
The dump body
Body may refer to:
In science
* Physical body, an object in physics that represents a large amount, has mass or takes up space
* Body (biology), the physical material of an organism
* Body plan, the physical features shared by a group of anim ...
is composed of five components: the floor, the two sides, the front wall and the canopy. The dump body is manufactured at Caterpillar Mexico in Monterrey, Mexico, as well as at least to a limited degree by WesTech of Casper, Wyoming in the western United States and shipped in component form to the customer site where it is assembled and welded into a monolithic structure before being joined to the frame during final assembly.
The frame
A frame is often a structural system that supports other components of a physical construction and/or steel frame that limits the construction's extent.
Frame and FRAME may also refer to:
Physical objects
In building construction
*Framing (con ...
is created from nine individual metal casting
Casting is a manufacturing process in which a liquid material is usually poured into a mold, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a casting, which is ejected or ...
s manufactured by Harrison Steel Castings Co., in Attica, Indiana
Attica is a city in Logan Township, Fountain County, Indiana, United States.
History
Attica was laid out by George Hollingsworth and platted by David Stump in 1825. The completion of the Wabash and Erie Canal through the town in 1847 brough ...
and by Amite Foundry and Machine, Inc., in Amite City, Louisiana. The smallest casting weighs and the largest casting weighs . The rough castings are shipped to the Caterpillar Decatur, Illinois, assembly plant.
At Caterpillar's assembly plant in Decatur, Illinois, the frame is assembled and the powertrain is installed and tested.
The nine castings that compose the frame are machined
Machining is a manufacturing process where a desired shape or part is created using the controlled removal of material, most often metal, from a larger piece of raw material by cutting. Machining is a form of subtractive manufacturing, which util ...
to provide clean welding
Welding is a fabrication (metal), fabrication process that joins materials, usually metals or thermoplastics, primarily by using high temperature to melting, melt the parts together and allow them to cool, causing Fusion welding, fusion. Co ...
surfaces. The castings are placed in a jig
The jig (, ) is a form of lively folk dance in compound metre, as well as the accompanying dance tune. It first gained popularity in 16th-century England, Ireland, Scotland, and other parts of the British Isles, and was adopted on mainland Eu ...
, and are initially joined by human welders. The frame is moved to a second welding station for further welding by robots" \n\n\n\n\n\n\nrobots.txt is the filename used for implementing the Robots Exclusion Protocol, a standard used by websites to indicate to visiting web crawlers and other web robots which portions of the website they are allowed to visit.\n\nThe sta ...
. The third and final welding stage is completed by human welders. To ensure quality, welds are tested using an ultrasonic
Ultrasound is sound with frequencies greater than 20 kilohertz. This frequency is the approximate upper audible limit of human hearing in healthy young adults. The physical principles of acoustic waves apply to any frequency range, includi ...
flaw detector. In total, of welding wire is used to join the individual castings into a monolithic frame.
After the frame assembly is completed, production workers attach hydraulic
Hydraulics () is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid counterpart of pneumatics, which concer ...
lines and electrical wiring to the frame before installing the engine and rear axle. The frame/powertrain assembly is tested and then partially disassembled to facilitate shipping from Caterpillar's Decatur, Illinois assembly plant to the customer site.[
]
Transportation
The engine, frame, axles and differential requires six to seven semi-trailer truck
A semi-trailer truck (also known by a wide variety of other terms – see below) is the combination of a tractor unit and one or more semi-trailers to carry freight. A semi-trailer attaches to the tractor with a type of hitch called ...
loads, the cab requires one semi-trailer load, the six tires require two semi-trailer loads and the dump body requires four semi-trailer loads. In total, one 797 requires 12 to 13 semi-trailer truck loads that originate at various manufacturing facilities and deliver to the customer site. If a 797 must be moved from one job site to another for any reason, it cannot be driven on public roads due to its exceptional size and weight. Moving a 797 requires dis-assembly, loading onto semi-trailer trucks, transport and re-assembly at the new location.
Final assembly
Final assembly of the 797 is completed by Caterpillar field mechanics at or near the customer site. Before the dump body can be joined to the frame, the dump body components must be assembled and welded together by a dedicated team, requiring seven to ten days per dump body. Final assembly of one 797 requires a team of seven mechanics working in three shifts around the clock, for 20 days, in addition to the time required to assemble and weld the dump body.[
]
Cost
Although the price varies based on individual customer specifications, each 797 costs approximately US$5,000,000.[
Other prices have been listed at US$3,400,000.]
Service life
All major components of the 797 can be serviced or replaced during the useful life of the truck, except for the frame. The overall service life of the truck is therefore dependent upon the durability of the frame which Caterpillar estimates to have a twenty-year service life.[
]
Competition
The Liebherr T 282 B and Bucyrus MT6300AC
The Bucyrus MT6300AC is an off-highway, ultra class, two-axle, diesel/ AC electric powertrain haul truck designed and manufactured by Bucyrus International Inc. in the United States. The MT6300AC is Bucyrus' largest, highest payload capacity haul ...
, as well as Caterpillar's own 798AC, match the Caterpillar 797F's payload capacity, but employ diesel/electric powertrains in contrast to the 797F's diesel-powered, mechanical powertrain. Both fall short of the BelAZ 75710
The BelAZ 75710 is an ultra class haul truck manufactured in Belarus by BelAZ. As of 2013, it was the world's largest, highest payload capacity haul truck.
Design
The BelAZ 75710 has a conventional two-axle setup but the wheels are doubled, one ...
's 500 short ton capacity, the largest of any haul truck in the world, which also employs a diesel/electric powertrain. Depending on customer requirements, lower payload capacity products such as the Komatsu 960E-1 and Belaz 75600 may also place competitive pressure on sales of the 797F.
Specifications chart
See also
* Haul truck
Haul trucks are off-road, heavy-duty dump trucks specifically engineered for use in high-production mining and exceptionally demanding construction environments. Most are dual axle; at least two examples of tri-axles were made in the 1970s. Hau ...
References
External links
2009 F-Series Mining Trucks Press Kit
- Caterpillar Inc.
Product Safety > Off-Highway Tractors and Trucks
- Caterpillar Inc.
Viewpoint - Perspectives on Modern Mining
- Caterpillar Inc.
{{Authority control
Caterpillar Inc. vehicles
Haul trucks
Vehicles introduced in 1998