In the context of trucks and trailers, sustainability covers the broad aspects of cost, environment and transportation. Building these vehicles in a more efficient way can entail less maintenance, higher payloads and longer product life.
Upgrading dump trucks and tippers from mild steel to Hardox® wear plate can also entail the use of fewer components, which can improve the production flow and make less of an impact on the environment.
When looking at the costs of using Hardox® wear steel, a long-term perspective must be taken. Simply comparing the process level per ton between different steel grades does not offer a complete picture of costs. Although a tipper or dump body in Hardox® wear steel initially involves a higher upfront investment, the cost benefit will be realized over the lifetime of the tipper. A tipper body made out of Hardox® will outlast a body in mild steel by 2-3 times.
When using high-strength steel like Hardox® wear plate, designers can specify thinner steel plate, which often also helps to substantially reduce the cost of both processing and materials. Thinner gauges help to drive down the costs of cutting, bending and welding in the workshop. Laser cutting in in high-strength steel such as Hardox® wear plate is no different from cutting in mild steel, and fabricators can decrease cutting time thanks to the thinner gauge. In most cases, welding thinner material offers the greatest cost reductions because there are fewer consumables and welding speed can be increased.
The good bendability of Hardox® wear steel can also help to reduce the number of welds needed. Bending our steel profiles generally does not require greater force than profiles in a thicker gauge made from conventional steel. However, the spring-back of Hardox® wear steel is greater than for conventional steel and needs to be compensated for during fabrication. In addition, using Hardox® wear steel enables the use of fewer components, which can result in less material needed and thus a higher value per ton.
A lighter vehicle made using less steel helps to reduce environmental impact by saving on primary energy resources and reducing greenhouse gas emissions. In the life cycle assessment of a vehicle, different phases are often analyzed. When an upgraded dumper or trailer is compared to an original design in conventional steel, steel production and service life are dominating factors. The latter often accounts for 90% of the vehicle’s total environmental savings. When analyzing service life in the case of weight-limited cargo, the weight of the vehicle is considered. The fuel consumption of road vehicles depends on several resistance factors the vehicle has to overcome during its operation.
Except for aerodynamic resistance, all resistance factors are linearly dependent on vehicle mass. The aerodynamic resistance, however, depends on the vehicle’s dimensions and speed. Therefore, besides its mass, speed, acceleration and the gradient (hilly or flat) also affect the vehicle’s fuel consumption. These factors are highly dependent on the driving conditions and driving behavior. With the same driving conditions assumed, the correlation between fuel consumption and vehicle weight is linear, and the fuel savings corresponding to a specific weight savings is independent of the vehicle’s absolute weight.
Fast vehicles driven at a steady speed will have high aerodynamic resistance and low acceleration resistance, and thus moderate specific energy savings through weight reduction. Consequently, slow vehicles that have frequent stopping and acceleration will gain high fuel savings through weight reduction.
A lighter and stronger dump truck or tipper has a direct, clear benefit for the truck owner, since maximum vehicle weight is limited by law. A lighter configuration allows the payload to be increased on every trip, and in many cases less fuel consumption can also be observed. A conservative estimate of fuel savings is about 0.55 l/100 km (about 428 mpg) per 1 metric ton of weight reduction.
This directly affects the balance sheet of the truck owner. Depending on the type of vehicle and the upgrading approach, the total weight can generally be reduced by 500 to 2,000 kg (about 1,100 to 4,400 lbs.) by using Hardox® wear plate. By selecting the most suitable grades for the application, costs associated with maintenance can also be reduced. Combining high strength with abrasion resistance can improve meeting these tough demands and increase vehicle performance.
The information in this report is only applicable to SSAB’s products and should not be applied to any other products than original SSAB products.