Articulated Dump Trucks: Heavy Hauling Made Easy

A common mistake is assuming that rigid and articulated dump trucks (ADTs) are alike. Although they both have massive hauling capabilities, the fact is each truck type has specific features that are valuable in certain applications.

Mon September 25, 2017
Aaron Kleingartner

One of the most common mistakes made when selecting an off-highway haul truck is assuming that rigid and articulated dump trucks (ADTs) are alike. Although they both have massive hauling capabilities, the fact is each truck type has specific features that are valuable in certain applications. This article lays out the benefits of operating ADTs for moving materials in construction applications.

An ADT's design offers several off-road performance advantages when working in earthmoving and hauling applications. Since their simple, yet effective design can be very different from other pieces of hauling equipment, it is important that the trucks are compatible with specific tasks.

Owners should first identify the tasks the ADT needs to perform. If the tasks are routine and regular, owners will likely purchase an ADT; however, if the tasks are performed only periodically, it may be best to rent the machine on an as-needed basis. Pairing an ADT with the properly sized loading equipment, assessing how easy the machine is to service, selecting the proper tire for the application, understanding the options and accessories available and what multiple safety features are available should also be considered.

By considering these six tips, owners can better select an ADT that excels at hauling tasks:

1. Complete tasks more efficiently

ADTs are designed to quickly move large amounts of material — such as dirt, rock, sand and gravel — with the lowest cost per ton transported in mind. Compared to rigid dump trucks or other earthmoving equipment, such as scrapers or pans, ADTs perform well in soft ground conditions and are commonly found on job sites in the early phases of site development, typically when ground conditions are not ideal.

ADTs are efficient, increase productivity, and reduce downtime and daily operating costs because of the following features:

  • Articulation joint
  • Semi-independent front suspension
  • Limited-slip differentials
  • Inter-axle differential

ADTs can increase productivity and uptime because they are designed to operate in conditions that can limit other earthmoving equipment productivity. For example, some ADTs have front and rear limited-slip differentials, and an inter-axle differential to improve truck performance by splitting power one-third to the front and two-thirds to the rear. A front-mounted turning ring and rear tandem bogie are two ADT features — a design feature for some brands — that maintain maximum traction and stability when traveling over very rough or soft terrain.

2. Match with loading equipment

The primary goal of any ADT owner is to maximize productivity by reducing haul cycles. One of the best ways to achieve these results in earthmoving applications is to match an ADT with the proper loading equipment, so equipment operators do not have to wait long between loads.

For example, owners who complete short hauls on a job site and own a midsize crawler excavator should consider purchasing a 30-ton ADT. If they need to move larger volumes over long distances, a larger excavator paired with a 40-ton ADT would likely fit their requirements. For most material hauling sites with good production, it typically takes four to six passes, on average, to fill an ADT.

3. Minimize downtime by planning ahead for maintenance

The last thing equipment owners want to do is waste valuable time servicing their machines. So before selecting an ADT, make sure it has good serviceability — easy access to the engine compartment on all sides and the transmission.

Like any piece of construction equipment, proper and timely scheduled maintenance will extend the life of the machine and save the owner money over time. To better predict expenses, owners should consider creating a planned maintenance (PM) contract. With a PM contract, servicing time is typically based on the manufacturers' optimal service schedule requirements. In addition, a PM contract ensures that any necessary maintenance will be performed as required to help minimize any machine issues that can be caused because of a lack regular maintenance.

In addition to a PM contract, ADT owners should perform three other preventive maintenance procedures:

  • Inspect the auto-lubrication system, if installed, to ensure that there is no premature component failure due to lack of grease
  • Assess tire air pressure, wear and damage on a regular basis
  • Monitor engine temperature and rpm history to prevent engine damage and major premature repairs with telematics

Educated and dependable product support is critical for all heavy equipment. Make sure to choose a dealer that has product specialization and trained mechanics, offers great response times and has good parts in stock.

4. Select the proper tire

When working in earthmoving applications, it is important to choose tires carefully to minimize costs. The right tires contribute significantly to an ADT's tractive force, which is determined by the tread design, remaining tread life and tire inflation, along with ground conditions at the job site.

The most common tires for ADTs are radial E3 or E4 tires; however, E3 tires offer better traction for sites that have soft soil conditions. Individual tire manufacturers can inform ADT owners and operators about which rubber compounds will provide longer life in earthmoving and hauling applications.

5. Expand versatility with multiple options and accessories

ADTs operated in earthmoving and bulk hauling applications may be equipped with options and accessories to help increase their potential. Tailgates, for example, help to minimize spillage from the truck's dump body and improve productivity. In addition, a heated body kit also is important, especially in colder climates, because it helps divert the engine exhaust through the channels in the dump body, keeping materials from freezing. Cold-weather starting kits and heated rear mirrors are other useful options for ADT operators working in the northern United States and in Canada.

6. Consider safety features

When selecting an ADT, owners should understand the machine's safety features. The location of the turning ring, or oscillating joint, of one ADT manufacturer helps keep equal weight on the front tires when loaded and turning. Unequal weight distribution can lead to instability.

In addition, some ADT manufacturers have addressed compromised sight lines with rear sloping frames to help lower the center of gravity for more equal weight distribution, and improved stability when fully loaded. The frames also improve tractive effort, minimize tire wear and lower ground-bearing pressure.

Large, well-placed and properly adjusted rearview mirrors help give a continuous view of the rear wheels when backing up and provide a higher degree of safety while on the jobsite.

By looking at the ADT's overall performance, versatility, serviceability and safety features, owners in earthmoving and hauling applications can make an educated decision about whether an ADT will fit into their fleets.

For more information, visit www.DoosanEquipment.com.

This story also appears on Construction Equipment Guide.