Introduction

Heavy machinery, known by the other terms: Engineering/construction equipment, earth movers, heavy equipment or just plain equipment, are machines,vehicle machines, in the most basic form, are compound machines composed of simple machines. These components make up the five equipment systems: implement, traction, structure, power train, control and information. Through the mechanical advantage of a simple machine, the ratio between input force applied and force exerted is multiplied. Currently most equipment use hydraulics as a primary source of transferring power. The use of heavy equipment has a long history. Vitruvius a 1st century B.C. engineer gives detailed descriptions of Roman heavy equipment and Roman cranes in his treatise De Architectura.
Heavy equipment requires specialized tires for various construction applications. While many types of equipment have continuous tracks applicable to more severe service requirements, tires are used where greater speed or mobility is required. An understanding of what equipment will be used for during the life of the tires is required for proper selection. Tire selection can have a significant impact on production and unit cost. There are three types of off-the-road tires, transport for earthmoving machines, work for slow moving earth moving machines, and load and carry for transporting as well as digging. Off-highway tires have six categories of service C compactor, E earthmover, G grader, L loader, LS log-skidder and ML mining and logging. Within these service categories are various tread types designed for use on hard-packed surface, soft surface and rock. Tires are a large expense on any construction project, careful consideration should be given to prevent excessive wear or damage.

Wheel Excavator

The Caterpillar 300 family excavators provide governmental agencies with more working advantages, whether you need more digging depth, more power, greater reach, more lift capacity, higher breakout force or more swing torque. The Caterpillar 300 Family Excavators are recognized by their sleek, modern styling and feature innovative hydraulic systems that put power where and when it's needed most.Increased lifting capacity, improved cycle times and ease of operation lead to increased productivity and lower operating costs.

Telehandler

Move massive amounts of material fast with a
NEW LM5000 Series telehandler. A combination of
outstanding operator efficiency and raw power and
lifting performance makes these new machines the
most effective way to load, stack, scoop and dig.

Larger, more comfortable cab
The spacious modern cab makes you more
comfortable, and more productive. The cab itself is
rounded with expansive visibility to the work area
around you.
Increased lift capacity
Lift capacity up to 8,800 pounds and a lift height
up to 31.5 feet allows you to do things that skid
steers, tractors, wheel loaders and fork lifts can’t,
like stack large balers six to eight levels high, scoop
a bucket of silage from the top of a bunker silo, and
much, much more.Improved reliability,Designed and manufactured by New Holland.

Pipelayers

Cat Pipelayers have been the standard of the pipelining industry for decades. A worldwide network of Caterpillar dealers, in tune with the special high production needs of pipeliners, supports these durable, dependable machines.
Engineered for demanding work. The 572R Series 2 power and versatility, combined with rugged components, are designed for tough and varied working conditions. This machine offers you the reliability and durability you expect from Cat Pipelayers

Cold Planer

A cold planer (also known as a pavement planer, pavement recycler, milling machine or rotomill) is an engineering vehicle used to remove bituminous or asphalt concrete from roadways, resulting in a smooth, even surface. This is accomplished by bringing a spinning mandrel or "head" into contact with the pavement at an exact depth or slope. It is normally fed by conveyor into a dump truck, but can be left in place or "wind-rowed" to be removed at a later date.The new PM-102 combines enhanced production capabilities, optimized performance and simplified service to complete tough milling applications with productive results. The Caterpillar 3126B ATAAC engine is dependable and field proven meeting U.S. EPA Tier 2 and European EU Stage II compliancy. Designed for high production and long life, the PM-102 rotor has quick release conical tool holders for quick and easy tool replacement. And the conveyor can be folded to reduce machine dimensions during transport.

Front shovel

Developed specifically for high production mining applications, the 385C Front Shovel delivers high bucket fill factors and fast cycle times to maximize your productivity. Designed and built to meet the performance and reliability expectations of Cat customers, this machine delivers dependability.The integrated engine oil and filter system extends service intervals. This combines the oil stabilizing systems, Reserve and Centinel, with the Eliminator self cleaning oil filter to extend, with oil analysis, the oil change interval to 4000 hours. Make and model 2 x Komatsu SDA16V160 Type 4-cycle, water-cooled, direct injection Aspiration Turbocharged and aftercooled Number of cylinders 16 Rated power @ 1800 rpm (SAE 1995/J1349) 2 x 2,010 HP 2 x 1500 kW Governor All-speed, electronic.

Bulldozer

A bulldozer is a crawler (caterpillar tracked tractor), equipped with a substantial metal plate (known as a blade), used to push large quantities of soil, sand, rubble, etc, during construction work. The term "bulldozer" is often used to mean any heavy engineering vehicle (frequently loaders and in particular track loaders), but precisely, the term refers only to a tractor (usually tracked) fitted with a dozer blade. That is the meaning used here.Sometimes a bulldozer is used to push another piece of earthmoving equipment known as a "scraper". The towed Fresno Scraper, invented in 1883 by James Porteous, was the first design to enable this to be done economically, removing the soil from the cut and depositing it elsewhere on shallow ground (fill). Many dozer blades have a reinforced center section with this purpose in mind, and are called "bull blades."

Compact track loader

Newest and Smallest Bobcat Compact Track Loader Has It All
Photo Gallery
First owners of the T140 compact track loader report that the new Bobcat® K-Series machine is just the ticket for working limited-access areas in backyards and in-between the closely spaced houses in today's new suburban subdivisions.
The T140 measures a mere 55-in.-wide (without bucket) and weighs just 6,660 lb. It combines the traction and flotation of a dedicated rubber-tracked undercarriage with the ability to slip in and out of tight areas and has the power to work quickly and productively.
Impressive traction and breakout forces make the T140 ideal for digging and grading jobs. You can also use it to extend your work season and money-making opportunities because it works so well in muddy or soft soil conditions and terrain. Plus, it treads lightly across lawns, patios, sidewalks and other sensitive surfaces to reduce site damage and repair costs.
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Skid steer loader

A skid loader or skid steer loader is a rigid frame, engine-powered machine with lift arms used to attach a wide variety of labor-saving tools or attachments. Though sometimes they are equipped with tracks, skid-steer loaders are typically four-wheel drive vehicles with the left-side drive wheels independent of the right-side drive wheels. By having each side independent of the other, wheel speed and direction of rotation of the wheels determine the direction the loader will turn.
Skid steer loaders are capable of zero-radius, "pirouette" turning, which makes them extremely maneuverable and valuable for applications that require a compact, agile loader.
Unlike in a conventional front loader, the lift arms in these machines are alongside the driver with the pivot points behind the driver's shoulders. Because of the operator's proximity to moving booms, early skid loaders were not as safe as conventional front loaders, particularly during entry and exit of the operator. Modern skid loaders have fully-enclosed cabs and other features to protect the operator. Like other front loaders, it can push material from one location to another, carry material in its bucket or load material into a truck or trailer.

Crawler carrier

A Full 360-Degree Rotation Capability; Forward-Facing Operator Position Under Any Conditions; No Space Required for U-Turns - The ability of the cab and dump body-integrated upper structure to rotate 360 degrees enables dumping at any angle, while minimizing site damage. This ability also results in minimal wear of pads, due to reduced steering necessity. The full rotation capability also means the operator can always execute jobs in a forward-facing position, leading to dramatically enhanced speed of operation, without sacrificing comfort.

Rigid backhoe loader

Spacious and comfortable operator station allows 360° visibility. An adjustable suspension seat is standard. Switches and gauges are clustered to simplify operation. Powerful engine and hydraulics provide fast, precise, and comfortable operation. Two working modes allow the operator to choose between maximum power and minimum fuel consumption. Standard arm has a 4276 mm 14'0" dig depth. Reversible outrigger pads accommodate both earth and paved surfaces. Heavy-duty power shuttle transmission and axles allow the WB142-5 to travel up to 37 km/h 23 mph.

excavator

An excavator is an engineering vehicle consisting of an articulated arm (boom, stick), bucket and cab mounted on a pivot (a rotating platform, like a Lazy Susan) atop an undercarriage with tracks or wheels. Their design is a natural progression from the steam shovel.Excavators come in a wide variety of sizes. The smaller ones are called a mini-excavator or compact excavator. One manufacturer's largest model weighs 84,980 kg (187,360 lb) and has a maximum bucket size of 4.5 m³ (5.9 yd³). The same manufacturer's smallest mini-excavator weighs 1470 kg (3240 lb), has a maximum bucket size of 0.036 m³ (0.048 yd³) and the width of its tracks can be adjusted to 89 cm (35 inches). Another company makes a mini excavator that will fit through a doorway with tracks that can be adjusted to only 70 cm (28 inches) wide.

Road Reclaimer

The "S" in Wirtgen’s new WR 2500 S Road Reclaimer and Soil Stabilizer stands for "super," according to company promotions. The top-of-the-line model has a new fuel-injection system that boosts its 12-cylinder engine’s power from 610 to 670 horsepower (455 to 500 kW). Wear is minimized in the redesigned, reinforced cutter housing by means of multiple wear plates, and the cutter drum has easier-to-service bolt-on end rings. Cooling performance, operator comfort, and ambient particulate levels have been improved, and a new dual cyclonic air precleaner will extend the service life of the air filtration system.

Road Rollers

A road roller (sometimes called a roller-compactor, or just roller) is a compactor type engineering vehicle used to compact soil, gravel, concrete, or asphalt in the construction of roads and foundations.

In some parts of the world, road rollers are still known colloquially as steam rollers, regardless of their method of propulsion. This typically only applies to the largest examples (used for road-making).

Road rollers use the weight of the vehicle to compress the surface being rolled. Initial compaction of the substrate is done using a pneumatic-tyred roller, with two rows (front and back) of pneumatic tyres. The flexibility of the tyres, with a certain amount of vertical movement of the wheels, enables the roller to operate effectively on uneven ground. The finish is done using metal-drum rollers to ensure a smooth, even result.

Rollers are also used in landfill compaction. Such compactors typically have knobbed ('sheeps-foot') wheels, and do not achieve a smooth surface. The knobs aid in compression due to the smaller area contacting the ground.

Grooming Mowers

Frontier equipment economy grooming mower: 48, 60, and 72 inch cutting widths Frontier of grooming mowers feature the iMatch ASAE Category I quick attach hitch system. this innovative and affordable device converts a three-point hitch to fixed hooks and attaching points, which allows for easy connection. Simply back up your tractor and slide on the PTO shaft, the iMatch hitch conversion kit is sold separately.
When you've got demanding mowing projects in store, why settle for anything less than equipment that's rugged reliable and ready to go when you are? With frontier grooming mowers, you don't have to settle. Whether you choose a versatile flex wing mowers, powerful rear discharge mowers, or sturdy side discharge mowers, you get exceptional strength, performance and dependability with every pass.

Post Hole Diggers

Rotomec equipment post hole digger: 6 inch to 30 inch auger diameter Rotomec Post hole diggers are constructed with heavy walled piping and sturdy gearbox is to ensure reliability whether it's for landscaping, farming or industrial purposes. choose from four models of diggers, and augur sizes ranging from six-inch for small post holes, all the way up to 30 inch holes for tree root balls. fully shielded drive lines with shear pins safety, and rugged dependable gear boxes on all models provide constant digging power.

Overseeder

Frontier equipment overseeder: for lush green turf. Lush, green turf is well within your reach. in just one pass, a Frontier multipurpose over seeder aerates, meters seed, plus incorporates and compacts the seed to ensure successful germination, with minimal disturbance to existing turf. The Frontier overseeder is your ticket to a healthy turf, where the work with parks, athletic fields, golf courses, or lawns. features include seed calibration handle, seed cups for precisely metered seed.

Box Blades

Frontier equipment box blades: several models to choose from Frontier box blades offer exceptional durability and utility for all your leveling and greeting applications. Both in standard and medium duty classes come with their rugged a frame that's welded from heavy-duty plate steel, and reinforced with structural supports to provide the durability tough jobs require.

Tractor Attachments

Frontier equipment rear blades: rear blades for your tractor Frontier equipment offers you a large selection of rear blades. from light utility work to heavy grading, frontier rear blades are designed for maximum versatility and performance. Whether you are shaping ground around your state or installing professional landscaping, you can choose from three classes standard, medium, and heavy, and 10 models to suit your needs.

Pendular Spreaders

Frontier Equipment spreaders: two models to choose from. Frontier pendular spreaders. if you demand on the nose accuracy and unbeatable performance in a spreader look no further than Frontier. Frontier pendular spreaders offer precision, versatility, and strength. And best of all, they're ready to go when you are. John Deere spreader attachments include a filter grate, sand and salt spout required for disbursing heavier material such as sand and salt. a rubber insert recommended when spreading high in moisture material. The tube provides a smooth surface to prevent clogging. An agitator extension, best suited for powdery or high humidity fertilizer applications. and hydraulic control, which allows the operator to open and closed the dispenser disk from the tractor seat.

Rotary Tillers

A rotary tiller, also known as a rototiller, rotavator, rotary hoe, power tiller, or rotary plough (in US: plow), is a motorised cultivator that works the soil by means of rotating tines or blades. Rotary tillers are either self propelled or drawn as an attachment behind either a two-wheel tractor or four-wheel tractor. For two-wheel tractors they are rigidly fixed and powered via couplings to the tractors' transmission. For four-wheel tractors they are attached by means of a three-point hitch and driven by a Power Take-Off (PTO).The powered rotary hoe was invented by Arthur Clifford Howard who, in 1912, began experimenting with rotary tillage on his father's farm at Gilgandra, New South Wales, Australia. Initially using his father's steam tractor engine as a power source, he found that ground could be mechanically tilled without soil-packing occurring, as was the case with normal ploughing. His earliest designs threw the tilled soil sideways, until he improved his invention by designing an L-shaped blade mounted on widely spaced flanges fixed to a small-diameter rotor.

Salvage Equipment

Salvage yards specializing in heavy equipment wreckage take out most of the working parts and store them for reselling to buyers who need such spares. The buyers also benefit from the heavy equipment salvage yards because otherwise they may have to replace heavy equipment with new ones incurring heavy expenditure. Find more info at www.heavyequipmentsalvage.info

While rummaging through heavy equipment salvage, it will be prudent to check whether the spare identified is in working condition and whether it is the correct spare for the heavy equipment. Otherwise, you will end up with unwanted and unworkable junk.

If you are lucky, you can easily identify a working spare from the collection of junk in the heavy equipment salvage yard, without spending too much money or much time in getting the required spare. Salvage yards come in handy, if the heavy equipment used by you is no longer in the production assembly of the manufacturers, spares could be identified only through sources like heavy equipment salvage yards.

Scrapers

a wheel tractor-scraper is a piece of heavy equipment used for earthmoving. The rear part has a vertically moveable hopper (also known as the bowl) with a sharp horizontal front edge. The hopper can be hydraulically lowered and raised. When the hopper is lowered, the front edge cuts into the soil or clay like a cheese slicer and fills the hopper. When the hopper is full (8 to 34 m³ (10 to 45 yd³) heaped, depending on type) it is raised, and closed with a vertical blade (known as the apron). The scraper can transport its load to the fill area where the blade is raised, the back panel of the hopper, or the ejector, is hydraulically pushed forward and the soil or clay load tumbles out. Then the empty scraper returns to the cut site and repeats the cycle.

Scrapers can be very efficient on short hauls where the cut and fill areas are close together and have sufficient length to fill the hopper. The heavier scraper types have two engines ('tandem powered'), one driving the front wheels, one driving the rear wheels, with engines up to 400 kW (550 horsepower).

Self propelled scrapers were invented by R. G. LeTourneau in the 1930s.^[1] His company called them Tournahoppers.

Two scrapers can work together in a push-pull fashion but this requires a long cut area.

Skid Steer Loaders

A skid loader or skid steer loader is a rigid frame, engine-powered machine with lift arms used to attach a wide variety of labor-saving tools or attachments. Though sometimes they are equipped with tracks, skid-steer loaders are typically four-wheel drive vehicles with the left-side drive wheels independent of the right-side drive wheels. By having each side independent of the other, wheel speed and direction of rotation of the wheels determine the direction the loader will turn.

Skid steer loaders are capable of zero-radius, "pirouette" turning, which makes them extremely maneuverable and valuable for applications that require a compact, agile loader.

Unlike in a conventional front loader, the lift arms in these machines are alongside the driver with the pivot points behind the driver's shoulders. Because of the operator's proximity to moving booms, early skid loaders were not as safe as conventional front loaders, particularly during entry and exit of the operator. Modern skid loaders have fully-enclosed cabs and other features to protect the operator. Like other front loaders, it can push material from one location to another, carry material in its bucket or load material into a truck or trailer.

Skidders

A skidder is any type of heavy vehicle used in a logging operation for pulling cut trees out of a forest in a process called "skidding", in which the logs are transported from the cutting site to a landing. Here they are loaded onto trucks (or in times past, railroad cars or flumes), and sent to the mill. One exception is that in the early days of logging, when distances to the timberline from the mill were shorter, the landing stage was omitted altogether, and the "skidder" would have been used as the main road vehicle, in place of the trucks, railroad, or flume. Modern forms of skidders can pull trees with a cable/winch, just like the old steam donkeys, or a grapple or a clam-bunk.

Soil Stabilizers

RM500 Rotary Mixer.
Performance and reliability you expect. The RM-500 combines superior performance and reliability to achieve the most demanding job specifications while maximizing machine uptime. With many enhanced features and options, the RM-500 is designed to work well in both full depth reclamation and soil stabilization applications.

Telehandlers

Caterpillar-branded TL Series telehandlers launched by JLG Industries, Inc., a leading producer of access equipment, aerial work platforms and telehandlers, are now officially available from Cat dealers in North America and Latin America. product series is based on existing JLG-branded designs combined with Caterpillar componentry and is manufactured at JLG's McConnellsburg, PA facility.The four new TL Series models, the TL642, the TL943, the TL1055, and the TL1255, have a capacity range of 6,600 - 12,000 lbs. and maximum lift height from 42 - 55 ft. With their heavy-duty three-section booms, greater load capacities and ability to place loads at greater distances, these machines are built with productivity in mind. In addition to the TL family, two models of the Belgium produced TH family are also now available to the North American and Latin American Caterpillar dealers.

Track Loaders

MOLINE, Ill. (March 16, 2005)--With many best-in-class features, the new Deere CT 322 and CT 332 set a new benchmark for compact track loaders (CTLs).

John Deere’s initial entries into the market deliver numerous advantages over current CTLs, including unmatched stability, visibility, serviceability, smoothness of ride, flotation and tractive efforts. Combine massive breakout forces--the best in the industry--with reinforced booms, thicker upper links, larger cooling capacity, and larger fuel tanks, and the result is the toughest CTLs on the market, according to Larry Foster, product marketing manager, John Deere Construction & Forestry Company.

“These machines were designed with rigorous compact track loader applications in mind--they can absorb the higher loads from increased pushing power and breakout forces,” Foster said. “They’re not just a skid steer with tracks.”

Track-type tractor

Authors note: The D9 and it’s competitors (such as the Komatsu D275A, can be purchased by contacting JCL Sales)

The Caterpillar D9 is a large track-type tractor designed and manufactured by Caterpillar Inc.

Though it comes in many configurations it is usually sold as a bulldozer equipped with a detachable large blade and a rear ripper attachment.

The D9, with 354 kW (474 hp) of gross power and an operating weight of 49 tons, is in the upper end, but not the heaviest, of Caterpillar’s track-type tractors, which range in size from the D3 57 kW (77 hp), 8 tons, to the D11 698 kW (935 hp), 104 tons.

The size, durability, reliability, and low operating costs have made the D9 one of the most popular large track-type tractors in the world, with the Komatsu D275A as one of its most direct competitors.

The D9’s primary working tools are the blade, affixed to the front and controlled by 6 hydraulic arms, and the optional ripper, which can be attached to the back. The blade is mainly intended for earthmoving and bulk material handling: pushing up sand, dirt and rubble.

The rear ripper is intended for use in loosening rocky ground and ripping out larger stones. It can also break frozen ground and excavate small ditches. The ripper can be replaced with a multi-shank ripper, allowing the bulldozer to comb the ground.

The size, power and weight of the larger track-type tractors dictate that they are used primarily for major projects. The D9 is most commonly found in use in construction, forestry, mining, waste, and quarry operations.

Trailers Equipment

All Pro Trailer Superstore offers a broad range of trailers to fit everyone's vehicle and budget. With their new spring line of dump trailers, equipment trailers and landscaping trailers just in, All Pro is gearing up for season and offering pre-spring discount pricing on trailers and trailer financing with deferred payments until spring 2008.

All Pro carries a full line of Cam Superline and Diamond C equipment trailers, gooseneck equipment trailers and heavy duty construction trailers ranging from deck between and deck over trailers to deck between styles including full-tilt and split-tilt equipment trailers. You can view Equipment Trailers For Sale at http://allprowest.com/3Equipment.html

Hydraulic dump trailers are available in light duty and heavy duty capacities and include low profile, heavy duty, gooseneck and deck over dump trailers by Cam Superline and light duty 5 x 8 to 6 x 12 dump trailers by Tilman. You can view Dump Trailer For Sale at http://allprowest.com/3Dump.html

Dump Trucks

The Komatsu HM300 Articulated Dump Truck is the most rugged and productive on the market, having been designed to bring rigid frame strength and reliability to the ADT sector for the first time. The Dash 2 model features Komatsu’s industry-leading ecot3 engine/hydraulics/transmission technology to deliver unrivalled fuel efficiency, combined with low emission levels.

Underground Mining equipment

The machines fitted with Trelleborg cab mounts are the R1300G, R1600G, R1700G and the R2900G LHDs, designed and built by Caterpillar Underground Mining in Burnie, Tasmania, Australia. Powered by Caterpillar engines from 136 kW to 321 kW gross power, they weigh from 27 tonnes to 67 tonnes. These vehicles are capable of carrying payloads from 6,800 kg to 20,000 kg up slopes of 1 in 5 or 20%.All machines in the range offer a choice between an open operator station and an enclosed cab. The open option incorporates a protective structure in accordance with ROPS (roll-over) and FOPS (falling object) regulations and is resiliently mounted via Treleborg's TrellExtreme ® Ultra Duty bushes. UD bushes are also used to isolate the optional enclosed cab, which offers a sound-suppressed working environment, as well as fresh, pressurized temperature-controlled air circulation, ergonomic design and a high level of comfort.

Wheel Dozers

The Caterpillar® 854K wheel dozer incorporates innovations to lower engine emissions and boosts fuel efficiency, improves reliability and serviceability, and optimizes operator efficiency and comfort. Specifically, the 854K uses a Cat C32 engine and a new radiator with improved heat transfer capabilities. A variable speed demand fan aids efficiency. For the operator, a new, larger cab includes a trainer's seat, and a new low-effort joystick controls all blade functions

Wheel Loaders

A loader (also known as: bucket loader, front loader, front end loader, payloader, scoop loader, shovel, skip loader, and/or wheel loader) is a type of tractor, usually wheeled, sometimes on tracks, that has a front mounted square wide bucket connected to the end of two booms (arms) to scoop up loose material from the ground, such as dirt, sand or gravel, and move it from one place to another without pushing the material across the ground. A loader is commonly used to move a stockpiled material from ground level and deposit it into an awaiting dump truck or into a open trench excavation.

The loader assembly may be a removable attachment or permanently mounted. Often the bucket can be replaced with other devices or tools--for example, many can mount forks to lift heavy pallets or shipping containers, and a hydraulically-opening "clamshell" bucket allows a loader to act as a light dozer or scraper. The bucket can also be augmented with devices like a bale grappler for handling large bales of hay or straw.

electric shovels

Power shovels are used principally for excavation and removal of overburden in open-cut mining operations, though it may include loading of minerals, such as coal. They are the modern equivalent of steam shovels, and operate in a similar fashion.
he digging phase consists of crowding the dipper into the bank, hoisting the dipper to fill it, then retracting the full dipper from the bank. The swinging phase occurs once the dipper is clear of the bank both vertically and horizontally. The operator controls the dipper through a planned swing path and dump height until it is suitably positioned over the haul unit (e.g. truck). Dumping involves opening the dipper door to dump the load, while maintaining the correct dump height. Returning is when the dipper swings back to the bank, and involves lowering the dipper into the tuck position to close the dipper door.

Drilling Machines

A drilling machine which is creates holes (usually called boreholes) and/or shafts in the ground. Drilling rigs can be massive structures housing equipment used to drill water wells, oil wells, or natural gas extraction wells or they can be small enough to be moved manually by one person. They sample sub-surface mineral deposits, test rock, soil and groundwater physical properties, and to install sub-surface fabrications, such as underground utilities, instrumentation, tunnels or wells. Drilling rigs can be mobile equipment mounted on trucks, tracks or trailers, or more permanent land or marine-based structures (such as oil platforms, commonly called 'offshore oil rigs'). The term "rig" therefore generally refers to the complex of equipment that is used to penetrate the surface of the earth's crust.

Bulldozers

A bulldozer is a crawler (caterpillar tracked tractor), equipped with a substantial metal plate (known as a blade), used to push large quantities of soil, sand, rubble, etc, during construction work. The term "bulldozer" is often used to mean any heavy engineering vehicle (frequently loaders and in particular track loaders), but precisely, the term refers only to a tractor (usually tracked) fitted with a dozer blade. That is the meaning used here.