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The new Caterpillar® 735 Articulated Truck features a new electronically controlled engine and purpose-built transmission, a new front suspension system, a new hitch design, a cooling system mounted to the rear of the cab and integrated with new styling, a new operator station and center-mounted cab. The 735 replaces the previous model, the D350E II, and offers improved productivity and fuel efficiency, smoother ride, enhanced comfort and superior visibility. The new model retains the cross-axle differential lock and inter-axle differential lock systems proven in the previous model.

The 735 is rated at 35 tons (31.7 metric tons) payload and produces net power of 365 hp (272 kW) from the Cat® 3406E diesel engine. The 735 is designed to deliver a superior horsepower-to-weight ratio as well as excellent flotation and traction to haul efficiently in difficult terrain.

Such attributes enable the 735 to excel in applications in general construction, road building, sand and gravel hauling, land restoration and mine reclamation, and landfill operations.

Electronically controlled engine and transmission

The electronically controlled engine and transmission offer complete system integration for maximum efficiency. The Cat 3406E air-to-air aftercooled turbocharged engine with electronic unit injection powers the 735. High torque rise of 53 percent delivers superior acceleration and lugging force on steep grades and in tough underfoot conditions. The engine has excellent fuel efficiency primarily due to electronically controlled unit injection fuel system, turbocharging and air-to-air aftercooling. The electronic control module, ADEM™ III (Advanced Diesel Engine Management III), improves performance, reduces exhaust emissions and aids diagnostics. The engine meets Tier 2/Stage II emissions regulations.

The eight-speed electronically controlled transmission is designed specifically for the articulated truck. The automatic transmission features Electronic Clutch Pressure Control with Controlled Throttle Shifting to manage shift torque and provide exceptional shift smoothness. The system reduces powertrain stress and clutch wear by coordinating engine speed, torque converter lock-up and transmission clutch engagements. Eight gears allow operators to precisely match operating speeds to job conditions for high productivity.

The standard engine compression brake provides additional braking force on downhill grades and reduces the need to apply the service brakes. Four modes of operation allow matching retarding power to the operating conditions.

The 735 incorporates the new radiator design that characterizes the Cat 700-Series trucks. The radiator is mounted behind the cab to improve the forward viewing area dramatically, protect the radiator from front impact and offer service access from both sides. The radiator is mounted at an angle to prevent heat transfer to the cab. A variable speed hydraulically driven fan improves efficiency and reduces sound levels.

New front suspension system for smoother ride

The new front suspension allows the axle to oscillate six degrees to provide a smoother ride and faster travel speeds over rough terrain. The front suspension uses an oscillating A-frame. The tie rod limits lateral movement of the A-frame. Independent, low-pressure oil-nitrogen suspension cylinders contribute to a smooth ride. Low pressure ensures consistent damping and increased seal life. The suspension mounting points are integrated into the axle housing for reliability and durability.

The new suspension system eliminates the need for lowering the suspension to transport the truck. The result is less downtime for moves from one site to another. The rear suspension features a mechanical walking beam design that extends component life and provides a stable ride for excellent load retention.

The traction control system uses a wet-clutch inter-axle differential and cross-axle differentials with wet clutches. All differentials can be engaged and disengaged on the go for fast cycle times. Inter-axle differential lock splits torque between the tractor and the trailer, and cross-axle differential lock provides full driveline locking for pulling through the worst conditions.

Oil-immersed, oil-cooled brakes are fitted to the front axles and the center axles. The fully enclosed brakes offer superior stopping capability and extended durability.

New front frame and hitch ensure durability

The front frame uses large box-section frame beams to handle torque loads. Castings handle areas with stress concentrations. The divergent frame design decreases stress in the hitch area and optimizes suspension geometry.

The articulating, oscillating hitch is a new two-piece construction. A durable, cast steel head is bolted to a forged steel tube. Large, hardened bearing areas and a hardened thrust face extend wear life.

New cab and operator’s station for high productivity

The new center-mounted cab combines with the new front suspension for a comfortable ride in all operating conditions. A smoother ride promotes higher productivity and reduces fatigue for consistent production during the entire work shift.

The center-mounted cab, curved windshield, increased glass area and low sloping hood give the operator of the new Cat truck the best all-round viewing of any articulated truck. The spacious cab is resiliently mounted and makes extensive use of sound-absorbing barrier materials to keep noise low.

The new Cat Comfort air suspension seat enhances operator comfort with a dual-sided support recliner and thicker cushions. It is fully adjustable to provide an optimal driving position. The cab also includes a full-size trainer seat. The steering column telescopes and tilts to accommodate the operator, and suspended pedals create more leg and foot room and are easier to reach.

The wrap-around, curved dashpanel exemplifies the ergonomic layout. Instruments are easy to read and controls are easy to reach. The switch for the inter-axle differential lock now is positioned next to the operator’s footrest for ease of operation. The Electronic Monitoring System (EMS III) constantly monitors critical machine functions and alerts the operator to potential problems. Flash memory in EMS III allows the software to be updated easily.

Reduced maintenance, quicker service

The 735 has extended engine oil change and hydraulic oil change intervals, extended life coolant, and no wheel-bearing adjustments required. Lubrication points are grouped together as are service points under the hood. The hood is raised and lowered electrically for easy access, and a manual override is provided. Test points are behind the cab and accessible from the ground.

Basic Specifications for 735 Articulated Truck

Engine Cat 3406E

Net power 365 hp (272 kW)

Transmission 8F/1R, electronic autoshift

Rated payload 35 tons (31.7 metric tons)

Body capacity 24.8 cu yd (19 cu m)

(heaped, SAE 2: 1)

Operating weight (empty) 65,609 lb (29 760 kg)

Top travel speed 34.7 mph (55.8 km/h)

http://news.thomasnet.com/fullstory/11745/1424

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GIA industri AB has long been known as a supplier of locomotives to the mining industry. Today GIA not only offers mine locomotives ranging from 2mt to 45mt, but has also diversified its range through the acquisition of Kiruna Truck, Häggloader and other lines to offer utility and service vehicles, equipment for high-speed tunnelling, ventilation and underground haulage trucks. GIA is represented in every continent of the world and around 80% of sales are export.

KIRUNA ELECTRIC TRUCKS

Kiruna Electric has all the characteristics that have made the traditional diesel-powered Kiruna Truck so successful in the global mining industry. It is a low profile, articulated, compact heavy-duty mining vehicle. The tare weight is substantially less than the payload.

The Kiruna Electric truck is manufactured in two versions, 50mt and 35mt payload. Units have been delivered to mines in Australia, Canada, China, Kazakhstan, Spain and Sweden.

The key operating advantages of the Kiruna Electric are:

* High speed on steep inclines – up to 20%
* Improved working environment – less noise, no exhaust fumes

GIA LOCOMOTIVES

Since 1950 GIA has manufactured and supplied locomotives for the mining and tunnelling industry all over the world. Today GIA is manufacturing both electrical and diesel locomotives in a range from 2t to 45t.

UNDERGROUND VENTILATION SYSTEMS

GIA SwedVent – GIA industri AB’s complete system for underground ventilation – comprise high pressure fans (axial fans), standard equipped with guide vanes and adjustable blade angles.

Air flows from 1.5m2/sec to 200m2/sec, diameters from 560mm to 2,240mm. The fans are made in an outstanding heavy-duty design and delivered complete with all necessary accessories such as silencers, starters and equipment for variable air-flow.

HÄGGLOADER – RAIL-BORNE DIGGING ARM LOADER

Häggloaders have been designed and developed to load hard, abrasive rock in conjunction with drifting and tunnelling operations, and for loading ore in mining applications.

The unique “digging arm-loading” technique has proven to be both effective and economical. It has also proven to be recognisably superior to other alternative loading methods in present use in tunnels.

RUBBER-TYRED EQUIPMENT

The Häggloader 10HR and 12HR are electro-hydraulic driven, feature trackless digging-arm loaders and are particularly suitable for use in drifts and tunnels with cross sections from 7m2 and upwards. The loaders, which are a further development of the 8HR variant, already to be found successfully operating on world markets, corresponds to high demands and expectations regarding continuity in operation, manoeuvrability and high output, even in narrow passages. The loading capacity is as high as 360g/hr (12HR).

Hydrostatic drive combined with powerful penetration ability, enables the loader to press firmly into the base of the rock pile. The material then falls directly onto the conveyor, allowing the operator to devote total concentration on operation and movements of the digging arms. In this manner, the optimal capacity of the loader can be exploited to the full.

SERVICE TRUCKS

GIA Utility/Service Truck. Two models are manufactured today i.e. GIA 111 which is an articulated truck and GIA TT 24 which is a rigid truck. Both models are 4-wheel driven in order to be able to operate in steep inclinations.

Both models can be equipped with boom and basket, scissors platform for anfo and emulsion charging, scaling, different kinds of installations and service works.

http://www.mining-technology.com/contractors/transportation/gia/

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Dynamic three-dimensional (3D) animation can be of significant value in improving the verification validation, and communication of discrete-event simulation (DES) models of construction operations, which in turn can make the models more credible and thus useful in operations planning and decision making. This paper presents research that led to the design and implementation of practical 3D animation methods to visualize multiply-articulated construction equipment in 3D animations of simulated construction operations. Using principles of forward and inverse kinematics, the writers designed and implemented generic virtual pieces of articulated construction equipment that accept task-level instructions from external software processes. DES models can configure and instantiate specific pieces of such equipment and instruct them to perform construction tasks using simple parametric text statements that embody a construction work-like terminology. Once instructed to perform specific tasks (e.g., load soil), these “smart” pieces of equipment (e.g., backhoes) automatically decipher the sequence and amplitudes of the elemental motions their components (e.g., boom, stick) must undergo to accomplish those tasks. The animation methods are implemented in a software tool called KineMach that integrates as an add-on with the VITASCOPE visualization system.

http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=
JCCEE5000019000004000356000001&idtype=cvips&gifs=yes

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Every year it seems there are more commercial vehicles like big tractor trailers on the highway and it shows no signs of easing up. To stay safe when driving on the highway you really need to know as much as you can about how these big trucks operate. Let’s take a look at some tips to help you stay safe on the road.

Sitting up high the drivers of these large commercial vehicles have a much better forward view but even with much larger side mirrors they have more blind spots than the typical driver does. You don’t want to follow these big trucks in their blind spots. You have probably seen the stickers on the back of some trucks stating “If you can’t see my mirrors I can’t see you” and this is true.

Larger vehicles like these need much more time and distance for accelerating and braking as well as much wider turning room. If you are driving in front of a big truck like this you should signal your intentions to change lanes or an upcoming stop sooner than you would normally to be on the safe side and give the truck driver time to respond to your actions properly.

Another big issue and one that I personally get aggravated with is that of excessive spray from the tires of these large vehicles in rain, snow, and slush. I live in Florida and I can tell you that when it is raining traveling on the major highways used by large semi trucks is extremely dangerous and at times you can see nothing due to all of the spray from the big trucks. My advice is that if you don’t absolutely have to be on the highway in those conditions stay off of it.

Not only do weather conditions affect visibility but so does time of day. Early morning and early evening hours can be dangerous as well when many people don’t use their headlights properly. You also need to be cognizant of the fact that many truck drivers are also driving long hours and may be overtired so you need to be cautious around them.

Big trucks are a necessity in our society and will not being going away any time soon. We have to be extra careful when sharing the highway with these vehicles because as stated in many cases they cannot see us.

http://www.articlecircle.com/cars-and-trucks/watch-out-for-big-trucks.html

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Contrary to the common myth, the job of a heavy equipment operator is not confined to just operating the bulldozer. Nor is it a gender specific vocation since both men and women are employed in this field.

If you can operate large machinery, are willing to work as a team, possess satisfactory communication skills and are open to suggestions for improvement, you can definitely be successful as a Heavy Equipment Operator.

Who is a Heavy Equipment Operator

Neither a designated trade nor designated profession, a heavy equipment operator maintains, repairs and adjusts the huge not so very delicate machines used in construction work. They also find employment at travel refuse collection routes or freight jobs.

Educational Qualifications and Eligibility Criteria

There are very few schools in the US that offer courses in heavy equipment training. Students are taught the basics of analytical and diagnostic techniques along with an in depth knowledge of electronics. Being a field job, the training imparted for the job is mostly done in practical surroundings.

The sub categories of the job position, such as a mechanic require a certification of validation, which needs to be renewed every 5 years.

Other than the educational factors, the first and foremost eligibility criterion is the possession of a Commercial Drivers License. Experience in driving trucks and smaller construction machinery is considered an added advantage. An ability to work with different people, to be open to the idea of additional training and responsibility and judgment of distance are some of the other criteria for hiring a heavy equipment operator.

A number of apprentice jobs are available for fresh graduates or trainees who have completed formal courses in heavy equipment operations. Most organizations pay a very nominal salary at the entry level to these apprentices.

Nature of the Job

The job of a heavy equipment operator is to operate machines such as the off highway trucks, graders, articulated trucks and loaders, scrapers, pavers, backhoes and shovels. As a junior operator, one could start out with operating small equipment and later move on to the heavier ones. The equipments under the former category include small rubber tire loaders and monitoring equipments.

With experience and training, one could eventually be promoted to senior positions such as a superintendent, job foreman, safety officer or trainer. If you are an independent minded person, you could also go ahead and set up a business of your own, after acquiring a few years of experience.

As this is a job that is required in almost every heavy manufacturing facility, one could easily relocate to any town or city without any worries about finding a decent job as a heavy equipment operator.

Salary

The standard workweek for heavy equipment operators is 40 hours. On an average, they could make approximately $20,000 to $49,000 a year (including benefits). A statutory holiday and vacation pay is also provided along with a group insurance for vision, health, dental, and retirement packages. Cumulatively, one could earn nearly 20% to 30 % of the basic hourly pay rate.

A word of caution though is that this job can take a toll on your health if you are not physically strong and if you dont possess the zeal to tackle the strenuous work conditions

http://www.articlecircle.com/career/how-to-become-a-heavy-equipment-operator.html

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A 40% increase in inventory space and 20% increase in production area highlight decision to adopt the narrow-aisle Aisle-Master lift trucks.

The Spicer Drive Shaft Div. of Dana Corp. recently installed 4 Aisle-Master narrow aisle, LP Gas internal combustion lift trucks at its Gordonsville, Tennessee, production facility.

The installation is part of an eleven-truck order for facilities in Michigan, Tennessee and Kentucky. The purpose was to create more space for production equipment and improve material flow between storage areas and production operations at these plants. Dana consolidated a number of operations into its Gordonsville, Tennessee facility and needed additional space within this facility to install production machinery, as well as to free up additional floor space for storage of raw materials and finished goods. The Aisle-Master lift trucks are a fundamental part of Dana’s initiative to increase productivity at it’s manufacturing plants where drive shafts are produced for the automotive industry.

Dana also used the opportunity to redesign much of the layout for a better flow of material between storage and production, improving cycle times and freeing trucks for additional activity.

The Spicer Driveshaft Division is an operating unit of Dana’s Automotive Systems Group. Dana’s core businesses are the manufacturing of axles, driveshafts, structures, brake and chassis products, fluid systems, filtration products, and bearings and sealing products. Dana combines these products and a variety of strategic services to support the production and aftermarket service sectors of its primary markets, supplying products to automotive manufacturers as well as three internal strategic business units, including the Heavy Truck, Off-Highway, and Automotive Aftermarket Groups.

By reducing aisle widths from 13 ft or 15 ft to 8-ft at the Gordonsville facility, manufacturing and storage space was created without increasing the size of the buildings. “We were able to increase our inventory storage by an average of 40% across our three facilities,” points out Mark Stebing, Training, Ideas, and Safety Coordinator at Dana. “We were also able to increase our production space at Gordonsville by at least 20%,” he adds. “Re-working the interior layout for narrow-aisle storage and relying on a flexible, multi-purpose truck was less expensive than the anticipated costs of new construction.”

Because Dana works three shifts, seven days per week, the lift trucks needed to be extremely reliable because downtime on the trucks would also affect receiving and production operations. “The significance of downtime can’t be over emphasized. We evaluated electric vehicles but full-shift operation wasn’t adequate and battery change time reduced the operating cycles available to one shift or another,” Stebing comments. “With global capabilities we manufacture and provide just-in-time delivery of fully integrated driveline solutions anywhere in the world.” The Aisle-Master is designed to work in 6 ft-6 in. aisles, saving space in areas where aisles between 12 ft and 15 ft are necessary. The articulated design allows the truck to be maneuvered easily in confined surroundings and the LPG engine permits indoor and outdoor use.

“We have an eleven truck fleet at Gordonsville and, while the Aisle-Masters have the capability to load/unload trailers with the low collapsed height 187 in. triple masts, we chose to leave this function to other trucks in the plant that can’t otherwise handle inventory as efficiently,” Stebing comments.

Dana handles products in a variety of load configurations:

• 48 X 40 and 90 X 40 wood pallets

• Collapsible wire containers

• Bulk corrugated containers on wood pallet bases

• Stackable plastic tote boxes carried on a plastic pallet base

Much of the lift truck activity is moving components in wire containers from indoor rack storage to production. The trucks also remove empty containers from production to an outdoor storage area.

Aisle-Master’s United States product manager, Finbarr Collins, oversaw the truck demonstrations and training at the Dana facilities during each of the three shifts. Dana management viewed this as a significant commitment because it ensured that the requirements of both its department managers and truck operators were taken into consideration to ensure the truck could fulfil the tasks required in all areas of the plant.

The fact that a 3-way, catalytic converter and fuel system controller are fitted to the Aisle-Master’s LP Gas, GM engine means the truck can be used both inside and out. “I’m used to an electric truck environment and we attempted to go ‘green’ with this application, but the facility was large enough, the ventilation adequate, and the productivity gains sufficient to move in another direction,” says Stebing.

Another important consideration for Dana was the truck’s reliability and spare parts availability. “Parts availability and reliability were key issues in our decision making,” says Mr. Stebing. “The fact that the Aisle-Master is fitted with a GM engine and most of the other components are available from US suppliers was an influencing factor. We work seven days around the clock, therefore we cannot afford any downtime from our fork trucks.” In addition to Aisle-Master’s US centralised spare parts, dealers will also carry a recommended stock of service items for routine maintenance at a local level.

Another important issue was operator training because the articulated concept is different from reach or counterbalanced trucks. “I wish I had this truck years ago,” says Stebing. “It’s a hoot to drive.” Aisle-Master provides a very comprehensive operator training program that covers both safety and operational procedures.

“The articulated design of the Aisle-Master means that operators can be trained quickly and my experience is that after a couple of days the drivers actually prefer the truck from an operational point of view compared to reach or counterbalanced trucks” says Aisle-Master’s Joe O’Brien. Visibility is significantly better and there is no rear end swing making the truck highly maneuverable and can result in less product and rack damage.

The financial benefits for Dana since introducing the Aisle-Masters include the fact that the truck can be used throughout the plant, reducing the number of application specific and area specific trucks required. Double handing is also eliminated, when necessary, because the truck can take product directly from the manufacturing or storage areas to the delivery vehicle.
With the demand for greater efficiencies now more relevant than ever, versatile products such as Aisle-Master, which can generate up to 50% additional storage space, will continue to become a popular equipment choice.

http://www.mhmonline.com/nID/1032/MHM/viewStory.asp

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An articulated truck is a vehicle that is most commonly used in construction work. Articulated trucks are used to haul heavy loads, sometimes over difficult terrain, and they can be considered a type of tractor-trailer unit. There are simple articulated trucks that haul goods, as well as articulated dump trucks that are also loaders.

The main feature of an articulated truck that puts it in a separate driving class is its drive system. The drive system is based on the number of wheels on the axles used to pull the truck. The most common system is the 6 x 6 system, in which the truck has six wheels on three axles and all are used when driving the truck.

Another system used is the 6 x 4 drive, in which only the rear four wheels are used when driving. The original drive system in articulated trucks is the famous 4 x 4 drive. This was designed for trucks that drive over the roughest terrain on the planet. The 4 x 4 drive system helps the truck maneuver over terrain that could be a potential problem for the goods being carried.

An articulated truck can be used to carry all kinds of goods. The 4 x 4 drive system, for instance, is most often used for loads such as flammable liquid. An articulated truck also has the ability to carry loads of up to 40 tons in weight. This is why it is so popular in the construction industry, in which heavy materials are used.

One of the problems of the articulated truck is found with the rear trailer. Because of its coupling system, the trailer works independently from the driving cab. A skilled driver needs to keep a watchful eye on the trailer using side view mirrors. Because of the independence of the trailer, the driver has no sense of the trailer’s motion. There are now video cameras that can be installed in the trailer to allow drivers to be aware of the trailer’s movement.

The articulated truck is one of the most versatile hauling vehicles in the world. Because of its versatility and mobility, it is used in a variety of industries, not just construction. Think of the large logging companies that transport huge numbers of trees; this would not be possible without the articulated truck. The military has a huge fleet of various types of articulated trucks, some of which are specially armored. You even have the articulated truck to thank for your garbage collection once a week.

http://www.wisegeek.com/what-is-an-articulated-truck.htm

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Articulated dump trucks exist solely to carry a heavy load fast over rough terrain. They have been in widespread use less than 20 years, and manufacturers are finally beginning to build trucks that will take the punishment a hard-hat cowboy can dish out after he’s seen the brochure pictures of these six-by-six contortionists working axle-deep in mud.

“The first thing project managers do when they get articulated trucks is save money by cutting out maintenance on the haul roads,” says Todd Perrine, equipment manager with Kokosing Construction in Fredricktown, Ohio. “One of the highest incidences of back injuries among equipment operators come from guys in artic trucks. They’re getting thrown around in the cab.”

With the guys who live and die by job costs planning to move dirt on rough roads, Perrine says the trucks seldom last as long as Kokosing would like. When he shops for articulated dump trucks (ADTs), he looks for an overbuilt drive train. The selection has been improving.

The ADT market leaders, Volvo and Caterpillar, draw their durability ace from being integrated manufacturers, meaning they build their own engines, transmissions, and other driveline components. Their proposition: If you build the drive system for maximum efficiency and durability, you can do a better job than those who buy components from vendors and assemble a driveline. The reasoning seems sound, but there are still plenty of ADT users who rent trucks for enough hours to justify a purchase. They prefer to rent because they don’t know how long the machines will last.

Until Komatsu’s entrance with the HM400-1 in 2001, Volvo and Cat were the only integrated ADT manufacturers. Komatsu has marketed its trucks largely from the durability angle, and the tactic seems to be affecting the intensity of ADT competition.

Komatsu’s 40-ton truck rolled out on power-train components adapted from rock trucks and wheel loaders. And in a move that asserts its commitment to durability, Komatsu is the only manufacturer that puts the sealed, wet-disc brakes on their 30-ton truck that serious ADT contenders reserve for 40-tonners. (Caterpillar does include wet-discs on its 35-ton 735.) Relying on the sealed brakes as retarders, too, plays into the durability claim. Komatsu says it results in less stress on the drive train than transmission retarders, which transmit brake torque through the driveline out to the wheel ends.
Components improving

Of course, the ADT field is replete with stout trucks manufacturers have assembled from venerable off-the-shelf components to serve buyers who want to save some money up front. Comparing 30-ton models, Deere, Terex, the CNH brands (Case, New Holland, Link-Belt), and Moxy sell trucks whose list prices average nearly $70,000 less than the three integrated manufacturers. The hourly ownership cost of a $310,000 assembled machine is nearly $2.40 less than that of a $350,000 unit, even if the less expensive unit falls 10 percent (700 hours) short of the integrated machine’s lifetime usage.

Most of the assemblers buy ZF’s 6WG260 countershaft transmission, and all of them drive ZF axles with limited-slip differentials in their 30-ton and smaller models. The electronic controller in the new series of this ZF gearbox engages the oncoming gear’s clutch before the clutch being released is fully disengaged. The result is uninterrupted delivery of torque. Reduced shock loading and larger clutch discs have stretched the anticipated life of the transmission to 10,000 hours.

Deere and Terex have the only trucks in the 30-ton class with planetary transmissions (both are ZF models). With no countershaft to spin, planetaries transfer more input-shaft torque to the axles. They also tend to be a little lighter and more rugged than countershaft alternates. That’s why planetary transmissions are common in 35- and 40-ton ADTs. With the TA30 introduced last month, Terex upped the ante in the 30-ton class significantly by going to ZF’s model 310. The same gearbox is used in some 40-ton ADTs.

The key benefits of virtually all engine/ transmission pairings today result from integration of electronic controllers. Linking the two computers allows wonders like simultaneously disengaging one clutch and engaging another, and adapting the clutch performance to manage driveline torque. You have to watch the tach closely to discern when the machine is shifting in the higher ranges.
Traction-control controversy

Virtually all ADTs have a switch the operator can throw to lock up the transfer case that proportions transmission output torque between the front and rear axles. Flip the switch and the drivelines fore and aft lock up to deliver equal amounts of power¡ªit’s sometimes called longitudinal differential lock. Only Volvo and Caterpillar continue to offer locking differentials for each axle. That’s transverse diff lock.

Caterpillar challenged the long-established dog clutches that Volvo uses for transverse lock-up with wet-disc clutches. Discs allow the Cat operator to throw on 100 percent transverse lock even when the wheels are spinning.

All other truck manufacturers use limited-slip differentials for transverse traction control. The diff switch in their cabs is only for longitudinal lock. Limited-slip is always on, which makes the operator’s job easier. It also makes the axles a little less expensive than lock-up clutches. Limited-slip proponents are quick to point out that it saves tires and driveline damage, and is quite effective in wheel loaders and other off-road equipment. But there’s no guarantee they’ll get your hardhat cowboy out of every quagmire that 100-percent locked axles will pull.
Creature comforts

Articulated-truck designers seem to be using sport-utility vehicles as a benchmark for cab comfort. Lists of creature comforts include power windows, heated mirrors with remote control, air-ride seats with adjustable lumbar support, and beverage coolers. The instructor’s seat in the new Terex folds forward so you can use the lunch tray and cup holders mounted on its back (like in minivans). You get the impression the marketers would just love to add a six-disc CD changer and retractable running boards.

It’s easy to take shots at the cab refinements because friction clutches and tractor seats were common on equipment as recently as 30 years ago. But the features are clearly intended to make operators more productive by keeping them more comfortable.

Productivity continues to be the articulated dump truck’s overriding objective. It keeps material moving when hauls are wet or rough. Manufacturers are competing for share of this market (which has nearly tripled in size over the past 15 years) with more durable transmissions, axles and brakes. And that makes it easier to meet the objective.
30-Ton Articulated Trucks: Wheel-to-Wheel
Make/Model Payloads (lbs.) Top speed (mph) Dump cycle (seconds) Outside turn radium Vehicle weight (lbs) Engine Torque (ft.lbs.) List price
One impressive number doesn’t guarantee a productive ADT. For example, Deere’s lightweight 30-ton truck has the best horsepower-to-weight ratio in the class, even with the smallest engine. Less-measurable numbers such as how often they get stuck make a big difference in choosing the right one.

http://www.constructionequipment.com/article/CA471255.html?taxid=8101

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Harris Printing Company has made a name for itself in West End, N.C. by being dependable and responsive to customer needs. Printing nearly anything from brochures to posters to catalogs, Harris has seen its business expand into a mid-size company and currently operates out of three facilities.

At the same time, continued growth also strained warehouse space. However, the company was not interested in relocating or adding warehouse space.

To accomplish that, the company turned to narrow aisle storage that increases capacity by 50%. Man-euvering down the narrow aisles called for new lift trucks as well. The solution was an articulated lift truck design that maneuvers easily within the seven-foot aisles.

“The people who were operating our lift trucks were a little apprehensive in the beginning,” says president and CEO Ricky Harris. “However, after working a week with the lift truck manufacturer, it was certainly a different story. Visibility is great, and it is really easy to learn to operate and maneuver in the narrow aisles.”

The lift trucks handle a range of loads including heavy and bulky paper rolls. A three-way catalytic converter for the propane-powered truck trims emissions and complies with EPA regulations for indoor use.

“The machine has been extremely reliable, without any mechanical problems,” Harris says.
mmh

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Lost Two Liters, Gained a Ton of Payload Moxy

The MT41 introduced at Conexpo-Con/Agg carries 2,000 pounds more payload than the truck it replaced, the MT40B II, and it’s Moxy’s first use of wet disc brakes. A drop in engine displacement, from Scania’s DI14 diesel to its 12-liter DC12, is masked by the fact that the turbocharged and intercooled DC12 carries the same horsepower and torque ratings (429 horsepower and 1,367 ft.-lbs.) as the 14-liter predecessor. The MT41 outweighs the MT40B II by about 3,000 pounds.

Number of models: 4

New models: MT41

Product-line features: All of the Moxy ADTs route Scania diesel power through ZF drive trains. The MT36 II is the most powerful per ton of gross vehicle weight in the 35-ton class, and the other Moxies rank among the two or three most powerful in their size classes. Moxy claims its unique articulation joint distributes weight to the front wheels in all situations, including sharp turns. The ring that allows front and rear frames to oscillate side to side is in ahead of the swing point. And Moxy says sloping its rear chassis down to the joint also improves weight distribution to each wheel for added stability.

KomatsuKomatsu

Different by Design

Komatsu is the most recent entry in the competition for articulated-dump-truck sales with a single-source power train. Komatsu ADTs diverge from the only makes that build their own engines, transmissions and drivelines (Cat and Volvo) with the Komatsu K-ATOMiCS countershaft transmission. Cat and Volvo use planetary-type transmissions. Komatsu breaks from all ADTs by speccing hydro-pneumatic struts in its rear suspension — a technology borrowed from its rigid-framed trucks.

Number of models: 3

Product-line features: All models have sealed wet-disc brakes, making the HM300-1 the only 30-ton truck in the world with them (Cat’s 735 is the only other 35-ton truck with wet discs). Komatsu relies on the wet-disc brakes as a secondary retarder after the exhaust brake, but a transmission retarder is optional.
John DeereJohn Deere

Light Trucks Move Loads Fast

With one exception, John Deere’s trucks are the lightest in each size class — Moxy’s MT36II weighs about 500 pounds less than the 350D. Deere uses its own 8.1-liter PowerTech engines in the 250D and 300D, and ZF’s Ecomat planetary transmissions. The 35- and 40-ton ADTs are powered by an 11.95-liter Mercedes V-6 diesel, through Allison planetaries. With good power-to-weight ratios, the Deere trucks are nimble even when loaded. Product manager Tim Averkamp says they deliver “haul cycle times in the range of 5 to 10 percent better than the competition.”

Number of models: 4

Product-line features: John Deere is working to move production of articulated dump trucks — under license from Bell, which currently builds the trucks in South Africa — to an existing Deere factory in Davenport, Iowa. All four trucks are expected to be built there by year’s end, for distribution throughout the Americas.
VolvoVolvo

Big Torque Gains from Smaller Diesel

Volvo traded the 9.6-liter Volvo D10 diesel for the 9.4-liter D9 used in the A25D and A30D. Horsepower dropped slightly in the 25-ton truck and increased slightly in the 30-tonner, but the big change is the torque increase. Net torque in the A25D jumped 25 percent, and the A30D saw a 20 percent increase. Volvo says their average fuel efficiency (measured in cubic yards moved per gallon of fuel) improved 5 to 7 percent.

Number of models: 5

Product-line features: The A35D and A40D are now being produced with Volvo’s D12D V-ACT engine, which recirculates a portion of the exhaust to the combustion chamber internally. There’s no exhaust aftertreatment. The Tier-3-compliant engines will handle high-sulfur diesel fuel. Volvo builds its entire driveline — engines, planetary transmissions, and axles with locking dog-clutch differentials.
CaterpillarCaterpillar

30-Ton Ejector Truck

At Conexpo-Con/Agg, Caterpillar announced the 730 Ejector Truck, a dump-body alternative that Cat applied three years ago to its 40-ton truck. Rather than tipping the load from the cargo box, the ejector’s hydraulic ram pushes a moldboard rearward to shove material out. Recent changes across Cat’s ADT line include a cab redesign with new instrument cluster and vehicle monitor. Cat also redesigned the elastomer suspension blocks mounted at the rear bogey, claiming they will last more than twice as long as the previous blocks.

Number of models: 6

New models: 730 Ejector

Product-line features: Cat applies its wet-clutch power-transmission technology not only in the planetary transmissions, but also in the ADT’s differentials. Interaxle differentials, which divide torque between the front and rear drives, use wet-plate, multi-disc clutches to transfer torque to the slowest turning member or provide 100-percent lockup on demand. Differentials in each axle also use wet clutches, allowing them to be locked on the go as well.
TerexTerex

Boosted Engine and Braking Power

Engine changes in the TA25, TA27 and TA30 to meet Tier 3 emissions regulations upgraded each model’s Cummins horsepower (16 percent more power in the TA30). Terex also boosted braking power by choosing dual-caliper dry disc brakes for these trucks, and making an engine-exhaust retarder standard equipment. The TA40 has been upgraded with wet-disc brakes all around.

Number of models: 5

New models: TA25, TA27 and TA30

Product-line features: Terex chooses Detroit Diesel Series 60 engines for the TA35 and TA40. All Terex trucks deliver power through ZF powershift transmissions, a lockable interaxle differential, and limited-slip differentials on each axle.
CaseCase

Powerful New Contender at 40 Tons

Case doubled its ADT lineup in January, adding 35- and 40-ton models to its 25- and 30-ton offerings. The 335 and 340 are powered by a Case-branded Iveco Cursor diesel with variable geometry turbocharger, and ZF countershaft transmissions and limited-slip differentials. The new front driveline has a limited-slip differential mounted on the transmission, which transfers power directly to each front wheel end via a pair of transaxles. This front drive system adds 4 inches of suspension travel. The 340 is Case’s only ADT with wet-disc brakes.

Number of models: 4

New models: 335 and 340

Product-line features: Case ADTs, manufactured in the CNH joint venture with Astra in Italy, have the lightest payload ratings in each of their size classes. For example, the 340’s 79,366-pound capacity is 4,400 pounds less than the highest-rated 40-ton hauler. But with fairly brawny engines, the Case trucks deliver high power-to-weight ratios. The 340 leads 40-tonners in terms of net horsepower per ton.
JCB

22-Ton 6×6 Is Largest in the Line

Last year JCB introduced its largest ADT and first 6×6 model, the 22-ton 722, with a 5.9-liter JCB diesel engine. Dump angle is increased to 74 degrees to clear cargo faster. The 722 uses a variable displacement piston pump to manage the hydraulic effort, reserving power for the drive train.

Number of models: 3

New models: 722

Product-line features: Like the two 4×4 JCB trucks, the 722 uses ZF’s Smoothshift automatic transmission and Super Max Trac limited-slip differentials. With capacities of 14, 18, and 22 tons, JCB has no ADT competitors in North America.

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