Tips for the top – innovations in tipper bodies

The impending switch to electric drivetrains could signal major changes to the stalwart truck of the construction sector

Innovations in tipper bodies are helping operators to maximise their resources, but the impending switch to electric drivetrains could signal major changes to the stalwart truck of the construction sector.

This article was originally published in the November 2021 issue of Commercial Vehicle Engineer magazine. To read the full issue, click here.

The construction sector is one of the most demanding on commercial vehicles, because of the size, weight and volume of materials that have to be transported, and the sites they work on. This means that truck and body manufacturers alike must constantly innovate to keep up with this demand.

Tipper bodies are a fixture in this sector and recent years have seen various new products and concepts products. For instance, tipper body manufacturer Aliweld now produces one-piece aluminium tipper bodies, distinct from the more traditional three-piece bodies.

Trevor Marshall, managing director of Aliweld, explains that the body came about after asking suppliers for years if it was possible to have a single sheet of aluminium made to Aliweld’s size and specification. “Then, when we could, we calculated the costs of two sheets – rather than six sheets – to manufacture the side panels of the body,” he explains.

“Taking into consideration the time it takes for two men to rack and stack single sheets, then cut and fold them one-by-one as opposed to one man lifting up the one-piece panel and just welding a top rail to it. The time saved was around 12 hours per body. This added to our one-piece floor sheet, which has proved a success with all our customers, who’ve had it, allowed us to build the bodies quicker and give the customer a body where the load simply slid out easily and didn’t stick on seam weld etc. The customers also prefer a body built in ‘one-piece’ rather than lots of joins.”

Marshall adds that the one-piece aggregate body is partly in response to customers’ desire to have better looking bodies, but that are also practical.

“We also have a traditional Asphalt body, again with a one-piece floor and side panels, but has a cleverly designed bottom rail which caps off the side insulation, holds the floor insulation, there’s a surface area for side lights and space for conspicuity tape all in one section. Customers like fine lines, simple but effective finishes.

“We have also always built the lightest monocoque body using less material to achieve this. This body had forward facing angled side pillars introduced in 2000 to reduce drag. Then around 2010 customers preferred to have their bulk bodies skinned on the outside giving a smooth exterior finish. We then designed a top rail and sourced large alloy sheets to achieve skinning the outer face of the body without using rivets etc. This body looks like the Asphalt body but it can be built any height and it has side pillars behind the outer skin sheet.”

Aliweld uses some of the toughest aluminium available – 5454 H22/H34 five series – in its bodies. “It seems to last longer,” he says. “It is harder to fold so you need the correct tooling.”

Cost rises are hurting

But while there is innovation in the sector, there are also problems. One of the main difficulties currently is the recent increases in the cost of raw materials, which is a “nightmare”, according to Marshall.

“As a nation, we seem to have been caught out by Brexit, import duties, Chinese mills implementing price increases, etc,” he says. “Why is this when we knew for years we were coming out of the European Union?

“Most aluminium has gone up about 35% and it’s having a massive impact on our business. So we have to guess the price when quoting for bodies.”

Aluminium prices peaked at the end of 2021 and, while prices have come down a little since, they are still markedly above where they have been for the majority of the past five years.

Alan Hunt, managing director for sales and marketing at Schmitz Cargobull, agrees that there seems to be no end in sight to the considerable price rises of recent months and it is having an impact on manufacturers. “Since the share of raw materials in the trailer is so high, this is directly reflected in the sales prices,” he says. “However, like all our vehicles, the tippers are also manufactured according to the customer’s needs and thus the prices vary depending on the equipment.”

It also means cost effectiveness is a primary concern for buyers, which is also driving the increasing use of trailer telematics, Hunt adds.

“The use of trailer telematics has already become firmly established in the market for curtainsiders and refrigerated trailers, but telematics is also becoming increasingly important in the transport of bulk goods thanks to intelligent networking and diagnostics, seamless documentation and central display and operation,” he says.

“It offers many advantages for the operator and makes everyday transport in the construction business safer, more transparent, more efficient and therefore more cost-effective.”

Schmitz Cargobull can equip its tipper trailers with an optional TrailerConnect telematics system, Hunt adds. “This can be optimally configured to the requirements of the construction industry with functions such as the brake pad wear indicator or tyre pressure monitoring system.

“The customer has the option of customising the TrailerConnect telematics system such as, in addition to standard functions, the determination of EBS operating data, the motion sensor and the wi-fi interface.”

Increasing payload

Allied to cost effectiveness is payload. Perhaps more than any other industry, construction is concerned with payload, as some operators get paid by the tonne of (for example) muck they take away. So taking weight out of a tipper wherever possible is imperative and is something that both truck and trailer manufacturers have worked hard to achieve in recent years.

For instance, MAN has taken weight out of its tipper engines and axles, as Nick Handy, head of product management for MAN in the UK, explains.

“MAN always had two eight-wheel tippers, an on-road aggregate vehicle with straight front axles and high point rear axles, and a muck and bullets heavy duty muckaway version with straight beam front axles and hub reduction axles,” he says.

“That suited the environment in which tipper operators worked 10-15 years ago, but more and more sites are paved or have at least had a dozering to make them accessible before the tippers come in and take the muck away, which means there is less of a need in the sector to have hub reductions.

“So now on our heavy-duty off-road tipper we have the option of high-point rear axles and that improved the payload on the vehicle by about 280kg. If you’re doing four loads a day, that’s one tonne extra in productivity. And when you are paid by the tonne, that’s of huge benefit.”

MAN has also taken weight out of its engine range used in tippers. “When we went to the 9.0-litre D15 engine in 2019, replacing the 10.5-litre D20, it saved 230kg of weight,” Handy says. “If you are reducing weight, it makes your transport operation more efficient in turns of fuel usage and carbon footprint.”

In addition, MAN has introduced other innovations into its tippers, such as the MAN Turning Brake, which takes the theory from other sectors of machinery, according to Handy. “In speeds below 30kph, when the system is engaged and on loose ground the system can sense the steering angle of the steering wheel and will apply some service brake pressure to the inside drive axle wheels to tighten the turning circle. In some situations, an operator can turn his eight-wheeler around in instances where he couldn’t if he didn’t have the Turning Brake.”

Elsewhere, for trucks in the Tarmac sector, MAN offers a paver brake. Historically, tarmac operators would normally have their driver feathering the footbrake depending on what the tarmac laying operator says – ‘stop’, ‘let it roll’ etc. With the paver brake, the operator can press the switch and it holds the residual brake pressure in the system to provide resistance against the paving machine so when you are going down a hill the truck with the tar in doesn’t run away from the paving machine. That’s simple but well received by operators in the sector.

Embracing electrification

Looking to the future, the government’s aim to end the sale of new trucks with internal combustion engines by 2040 means there will need to be significant change for the tipper sector and a potential move towards electric power.

Currently, most demand for electric trucks comes from the delivery sector. MAN’s Nick Handy notes that while tipper operators are increasingly concerned about their environmental impact – especially in terms of CO2 produced, as it increasingly crops up in tender applications – many operators are not thinking of converting to electric power yet.

However, there is a ‘quick win’ option to reduce CO2 that operators can do by converting to hydrotreated vegetable oil (HVO), Handy adds.

“Ever since Euro 6C, all our diesel truck engines are homologated to operate on HVO, which you can use instead of diesel, and it lowers your CO2 output quite considerably. A lot of tipper operators are looking at that now.”

John Comer, product manager at Volvo Trucks UK & Ireland, agrees that HVO can help to reduce emissions now, but that the future is gearing towards zero emissions from the tailpipe.

To that end, Volvo recently announced that its first zero tailpipe emissions tipper will be available in the first quarter of 2023.

But the move to electrification could mean a change in the way tippers are configured, away from 8×4 and towards Tridems – which Volvo’s electric tipper will be – according to Comer.

“The biggest single issue with electric vehicles is packaging – getting the energy on board,” explains Comer. “Take a Tridem; we measure the wheelbase from the first steer axle to the first drive axle, and we have an completely uncluttered space there with a Tridem wheelbase. But if it is a traditional 8×4 there is an axle in that space, and we need the space to get the 540kw of energy density on board.”

Another advantage of a Tridem is that it is on air suspension, rather than leaf, Comer adds. “The majority of 8x4s for construction are on leaf suspension,” he says. “The most common back end is a two-spring bogie, which has two inverted springs held onto two axles with a balance beam in the middle. They are simple and light and, when you have two 9.5-tonne axles, they compensate for each other.

“But air suspension reduces vibrations and, if you have paid a lot of money for batteries, you need to protect them. 

“Air suspension instantly reacts when you take a load off it. There was some concern in the tipper sector about that but the stability isn’t affected as when you tip an air-suspended tipper you let the air out of the bags anyway.

“The other thing with an air-suspended tipper is we would always ask for a sub-frame to mount the body on. Today, a traditional steel tipper is mounted directly to the chassis. We typically could build a steel suspended tipper with an 11-litre engine with an alloy body and alloy wheels and get a 20-tonne payload. A lot of people like the current set-up due to the productivity of them.

What is really needed?

A crucial question that the move to electrification will pose for operators in the construction sector is what configuration they really need for their trucks, Comer adds.

“Is the rigid eight-wheeler the future of construction?” he says, suggesting operators need to ask themselves, “Do I need a truck with a bogie on it? Can I have a trailer with a longer life and be completely independent? Do I need to keep my vehicle attached to its body? Could I not be more flexible and have a two-axle tractor unit and three-axle trailer, perhaps with a moving bogie and carry more payload that way?

“I’ll be operating at 40 tonnes and might get to 42 tonnes and, if I am 42 tonnes and lose a couple of tonnes for batteries, can I get a 20-tonne-plus payload and have a truck that, when it does need charging, can be separated from its body so the body is not tied up on a charger and give me a much more flexible operation?”

Comer notes that operators need to look at the broader picture. “Obviously it would take more detailed analysis, but when swapping from diesel to electric construction vehicles, operators shouldn’t just think about the driveline but what their operation really needs – is it still to move 20 tonnes or do they want a vehicle that could do something else should the market change?

“Operators have the chance to look at their operations and ask if they really need an off-road defined vehicle? Cities don’t like them and N3G vehicles only spend about 5% of their time in the quarry. Do I need that level of ground clearance? I am on paved ground? CLOCS now have guidance on site preparation to try and discourage operators from using N3G trucks.

“A tractor unit is like Thunderbird 2 – it can do lots of things. But a rigid, once you put a body on it then you’re tied to what you are doing.”

Tractor with Scmitz Cargobull tipper trailer

This article was originally published in the November 2021 issue of Commercial Vehicle Engineer magazine. To read the full issue, click here.

Dan Parton
Dan Parton
Dan Parton is a former editor of Truck & Driver, the UK’s biggest selling truck magazine. He is now writes for The Van Expert and The Truck Expert.

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