Articulated Truck Parts Diagram: Search and Learn About Articulated Dump Trucks
When it comes to moving materials across uneven ground, up and down slopes, through tight turns, and over the most difficult of terrains, it’s often the articulated truck that gets the call. Because of their unique design, articulated trucks have found a home on worksites where a rigid frame just won’t work. To learn more about how exactly an articulated truck is able to perform work other machines can’t, read on for an explanation of the parts of an articulated truck and how they all work together.
Articulated Truck Parts Diagram
Click a part or a label to learn more about the part, its function on an articulated truck, or to see and search that specific part at H&R.
When compared to the engines in automobiles and even other construction equipment, the engines on many articulated trucks range from large to gigantic. The engine on an articulated truck must be able to provide ample power to drive all systems on the machine while also propelling the machine forwards while carrying extremely heavy loads. The engine in an articulated truck must also balance output with working conditions to manage the overall efficiency of the machine. On the machines of today, this is often done through the implementation of new, smart technologies.
While an articulated truck is most commonly put to work for off-highway jobs, the travel distance for articulated trucks as they transport materials around a worksite can still be significant. To maximize the efficiency of the machine, the transmission in an articulated truck must be able to both provide enough speed for long hauls and provide enough torque to carry loads when fully-loaded. And since the worksites articulated trucks often call home can feature steep inclines and surfaces with less than ideal traction conditions, the transmissions must be designed to handle a wide range of conditions.
❱❱ Drop Box
The drop box on an articulated truck lowers the output shaft while also using a gear system to adjust the relative speed and torque of the output of the transmission.
The bed of the articulated truck holds the materials the truck is transporting. Articulated truck beds have to be designed with thick-bodied plating and strong reinforcements since articulated trucks consistently carry heavy and abrasive materials. The shape of the bed is designed to balance and secure a load, but loading a bed properly can still require a well-trained operator at the controls of the machine that is loading the articulated truck.
On articulated trucks that feature a tailgate, the tailgate allows the operator to maximize the size of their loads, secure the loads during travel, and dump the loads with precision.
The cab of an articulated truck is designed to provide operator safety and comfort, ensure operator visibility, and allow for every aspect of the machine to be controlled and monitored. Articulated trucks seldom work alone and often work in active environments so the cab must allow for the operator to quickly understand the conditions around them. Increasingly, the controls to drive the machine and lower and raise the dump bed are augmented with technology to monitor the conditions of the machine, the efficiency of the machine, and even the weight of loads.
The engine on an articulated truck can be called on to do intense, repetitive work in harsh environments. To help keep the engine cool during that work, a radiator at the front of the machine allows liquid coolant and a fan to continuously pull heat from the system and ensure the engine doesn’t overheat during long hauls and with a heavy load. Because of the common environments articulated trucks face, an operator must monitor any debris that could collect on the radiator and reduce the radiator’s ability to exchange heat.
❱❱ Oil Cooler
Similar to the radiator on the articulated truck, the job of the oil cooler is to reduce the temperature of specific parts of the machine. As parts in oil-based systems perform repetitive tasks the oil in the system can heat up and cause the system to lose efficiency and expose critical parts to troubling conditions. By maintaining proper oil temperatures, the oil cooler acts as a preventative tool to stabilize the internal temperatures of the articulated truck.
❱❱ Control Valve
At the heart of the hydraulics on an articulated truck a control valve regulates the speed and pressure of hydraulic oil and, in turn, the speed, power, and direction at which hydraulic parts operate. Since many of the moving parts on an articulated truck are controlled by hydraulic cylinders, it's the job of the control valve to ensure each moves smoothly and properly as an operator precisely controls every aspect of the machine.
❱❱ Bed Lift Cylinders
Hydraulic cylinders mounted on opposite sides of the machine are used to raise and lower the bed. By extending the cylinders, the bed lifts and pivots around a point at the rear of the machine. This action allows the machine to dump loads. An expert operator can finely control this dumping action to perfectly place loads. Since the weight of loads can be large, these cylinders are designed for routine and high pressure work.
❱❱ Steering Cylinder
A steering cylinder at the articulating point in the machine allows the front of the machine to alter its angle compared to the rear. This articulating action is what gives the articulated truck its unique maneuverability as the operator steers it around a worksite, avoiding obstacles and performing tight turns.
❱❱ Oscillating / Articulating Hitch
The oscillating hitch on an articulated truck grants the truck the ability to twist at the intersection of the front and rear frames of the machine. Compared to a truck with a rigid frame, this ability to twist relieves some of the strain and pressure on the frame as the truck navigates rough and unbalanced terrain since each half of the truck can freely twist to match ground conditions.
❱❱ Rear Frame
A large, heavy rear frame on an articulated truck holds all the rear components of the machine. The rear frame must be built to carry the heavy weight of these components, even when fully loaded, and to stand up to the intense forces of routine starting and stopping, impacts from below, and nearly constant vibrations from passing over rough terrain.
❱❱ Front Frame
The chassis of an articulated truck is divided at the point where it articulates. The front frame is the base structure for the front rims and tires, engine, and cab. It must be designed and built to handle the rugged terrain under the tires of the truck as it swiftly navigates a worksite.
Connecting each set of wheels in an articulated truck is a heavy duty axle that houses the axle shafts and differentials in the machine and connects the rims and wheels to the final drives and brake groups. The axles in an articulated truck must be sturdy to contain the high torque of internal moving parts, as well as protect internal parts from the unexpected impacts that are possible on worksites.
❱❱ Drive Shafts
Heavy-duty drive shafts run the length of the articulated truck and transfer power from the engine to each of the drive wheels.
❱❱ Rims and Tires
Large rims and tires on an articulated truck allow it to move smoothly over rugged terrain while maintaining operator comfort. Since articulated trucks are commonly required to travel considerable distances on a worksite, ground conditions are not always ideal, and the round-trip travel times of the trucks must be set to keep operations flowing, an articulated truck must be able to achieve some level of speed. Properly inflated tires and heavy-duty rims allow the machine to travel at speeds and over ground which would strain other machines.
❱❱ Brake Groups
The weight of an articulated truck combined with the weight of a load and amplified by the speeds at which the truck is able to travel means the braking power of the truck must be considerable. Brakes in the drive system of the machine must be able to stop the machine suddenly for safety, as well as help control the speed of the machine as it encounters sloping terrain.
❱❱ Final Drives
Final drives integrated into the axles of the articulated truck utilize a system of planetary gears to transfer power into the high torque output needed to propel the machine through gear reductions.
Differentials on an articulated truck change the direction of power as it is sent to each set of wheels, divide power between each set of wheels, alter torque through gear reduction, and allow each wheel to turn independently of one another. Since ground conditions for an articulated truck can be immensely variable, differentials on an articulated truck are designed to constantly provide proper intelligent traction control to each axle and each wheel on the truck.
Hopefully, you have a better understanding of how all the parts on an articulated truck work together to smartly transport materials around a worksite efficiently and effectively. If you’ve arrived here because a part on your own articulated truck is creating problems, our Parts Specialists are here to help. As a top dismantler of articulated trucks with the dedicated spaces to salvage articulated trucks of all sizes, our inventory of parts is tough to match. Just drop us a line and we’ll search both our inventory and our large connected parts network.
Articulated Truck Parts Diagram Image