Fuel Efficient Weight Lifting

Fuel Efficient Weight Lifting

The approach towards Commercial Vehicle (CV) technologies has changed due to better cognizance of safety, fuel efficiency and productivity. The ability to carry more cargo with better turn-around time and optimised cost is crucial for CVs. The emphasis has deepened on energy management, safety (due to better infrastructure roads and bridges), vehicle handling, timely delivery, emissions, fuel efficiency, and higher load carrying capacity.

A unique feature of the CV industry is its fragmentation. The market for bus and truck bodies is quite different from that of the last mile vehicles. The typical manufacturer of truck bodies produces a range of trucks. This sector contains many manufacturers that design, manufacture, and service equipment for a wide variety of users and uses, from garbage collection to cement mixers to interstate cargo movement to buses to half tonne last mile vehicles. Due to the lack of policy and regulatory imperatives, there is no uniformity of any kind over the assortment of CVs. A cost effective design for mass market CVs is lacking due to complexity in widespread variants and the heterogeneity of products.

LIGHTER MATERIALS

The load carrying capacity of commercial vehicles has gone up between 17 and 26 % over the last decade. This has been possible because of lighter materials being used in body building, chassis and other sub-systems. The use of super high-strength steels (HSS) has enabled reducing the wall thicknesses, and therefore achieving lightweight constructions. Review of various manufacturing processes showed that the old technique of roll forming showed a lot of untapped potential to exploit HSS. With flexible roll forming, deep-drawn parts could be produced with high precision automotive tolerances using HSS.

The use of ladder frame structures reduced weight by 10 % and main parts of the frame structure by 30 % using HSS in combination with innovative production methods. Such a percentage of vehicle weight reduction could result in about 12-20 % improvement in fuel efficiency. It is projected that the use of aluminium will be in double digits by 2020 in broader vehicle applications that could result in a corresponding increase in fuel efficiency. Furthermore, aluminium use in commercial vehicles has grown by 10-15 % per annum over the past 15 years. The use of magnesium parts for weight saving is also growing since these can be tuned to those critical frequencies where noise, vibration and harshness matters. This lower NVH threshold application is advantageous in light of the expanding footprint of relatively quieter electric vehicles.

NEWER DEVELOPMENTS

The regulations for better fuel economy have triggered many vehicle development and design initiatives such as aerodynamic styling of CVs, use of low drag accessories, low rolling resistance tyres and efficient powertrains. Projected data shows the potential for energy reduction in CVs is around 45 to 50 % by the 2020 timeframe.

Also, the use of new NOX and SCR technologies have reduced emissions and helped meet stricter emissions. The essential trade-off of investments in fuel consumption is that while the price per mile travelled is going down, the initial price of the vehicle is going up. Potential buyers may decide to postpone purchases but eventually appreciate the trade-offs. This effect could be stronger in heavy duty CVs than the light CVs because their expected lifetimes are longer. The same effect is obvious in electrified buses and hybrid trucks, although after a cost-benefit analysis it is seen that the operational costs are lower and savings are higher.

Eventually, global competition, sustainability of businesses and emphasis on lower carbon footprint is seeing an accelerated shift towards fuel-efficient heavier weight lifting, where every CV and its stakeholder win.