BODYBUILDERS

The Australian Mining Review recently interviewed David Pichanick, Global Manager Market Development and Innovation from Austin Engineering, to ask him about the enormous amount of research and development that has been poured into these revolutionary tru

AMR: What design features has Austin Engineering incorporated to allow them to achieve a 240t payload with ultra-class trucks?

DP: Ultra Class trucks range from payloads of 100 to 360 metric tonnes. In the first instance, we must take into account the both the empty and loaded Gross Vehicle Mass (GVM) of the truck in its OEM state.

For example, a truck with a 400t payload may have an empty GVM of 200t, giving a total GVM of 600t fully loaded. We have to match those specifications with our new trays to ensure that all the engineering aspects of braking, steering, front-to-rear axle loading, tyre loads and more are maintained.

We use complex simulation software to design our trays within these constraints before we start incorporating any improvements. Austin Engineering has over 50-years’ experience, so we draw on all that knowledge to create new features and benefits from front to back.

Factors such as load freeze, ore body type and wetness, anti-hang-up features, tray heating, wear resistance and specific dump criteria from each client are all incorporated.

The client’s needs are always put first and foremost and always with the highest payload achievable in mind and a the ability to deliver 4-5 years of reliable service from every tray.

AMR: How did you achieve approximately a 15pc reduction in body weight while also increasing the working payload?

DP: The short answer is through advances in steel technology. In the 1980s the Swedes began producing their quench and temper steel plate and that has now evolved into 500-Grade steel. This gives us more confidence in what can be achieved in our finished designs.

The availability of higher quality steel has allowed us to design lighter weight bodies that are capable of greater payloads but are still capable of delivering the same service life of previous models. The reduction in the tray’s GVM reduces the truck’s total unladen GVM and thus permits a greater payload to be carried while maintaining the OEM total loaded GVM. Once again, our unique software simulations have allowed us to maximise the gains achievable with these new steels.

AMR: What new characteristics are incorporated into the Ultima bodies that result in reduced maintenance costs for mining companies?

DP: The first is using the right type of steel in the right places around the impact zone to absorb that impact during loading. Another critically important feature that may not be instantly obvious is the height of the tray’s tail. With the advent of autonomously controlled trucks using active cruise control, there is always the risk of nose-to-tail collisions as slowing a mass of several hundred tonnes takes time.

Historically, the tail of the tray was quite low and that meant that in a front-torear collision, the tail of the front truck would hit the cab of the rear truck, causing significant damage – or injury if it was manned.

Thanks to our design software, we have

been able to develop a design with the tail kicked up higher so that it sits higher than the cab of a trailing truck but this also required the use of higher wear materials in the rear of the tray to overcome the resultant higher wear rates.

AMR: What else have these recent advances in steel quality allowed you to achieve in this new Ultima design?

DP: We are currently conducting trials around the world with new steels. We need to prove these new grades in the real world, given the vast array of variables we face when designing a body for a client.

We have some trays built with half one grade of steel and half with another to A/B test in the same application.

We then use scanners to measure wear and overall steel thickness every three months over a 12-month period. We also have nine different body styles around the world, each requiring variations in the steel used. This is part of our ongoing R&D to deliver the best possible, application specific, body.

We must also ensure that every batch of steel we use is consistent, so that if we build a series of say 20 bodies for a customer, each of those bodies has the same grade of steel in the same area – as per our design criteria.

AMR: How does the replaceable floor work? How does it compare to conventional body designs?

DP: Our JEC models have replaceable floors fitted to a skeletal frame. In some instances, the floor might have a service life of 20,000-hours but the frame might have a life of 60,000-hours.

So, this enables this enables the floor to be completely removed in a shift-anda-half and then completely replaced in another shift-and-a-half, which provides a very fast and cost-effective turnaround for the client. These bodies are particularly successful in very abrasive applications such as hauling magnetite, lithium or sand. The coarseness of the ore material produced after blasting can also have a bearing on tray wear.

AMR: What advantages in load stability and tipping time does the new V-floor design provide?

DP: With a flat floor, material typically wears in the corners. With our V-floor design corner wear is reduced, while the vee also controls the flow of ore, lowers the centre of gravity and reduces direct impact when loading. It can also help to reduce tip times.

AMR: How does the truck’s operating climate affect the construction of the body and the type of materials used?

DP: This question highlights the need to have a strong relationship with each client and really understand their application.

This forms the basis of any design and allows us to identify issues such as load freezing or sticking, analyse material flow, calculate tipping times to suit the input restraints of a hopper or crusher for example and even prevent damage to the tipping cylinders of the truck itself.

Safety is always the first consideration. For example, if the wrong steel is used in a sub-zero climate, a falling rock could easily punch through the body and cause significant damage to the driveline.

By working closely with the client and gathering as much information as possible in the first instance, we are able to create a design and use the right materials for that particular application. That ensures the greatest level of safety and the maximum payload to reduce the miner’s cost per tonne.

The Ultima Series truck bodies are up to 15pc lighter than OEM, deliver a 20t payload increase for a maximum of 240t per load, reduce fatigue wear and maintenance costs and improve the productivity of the load-haul cycle.

AMR: Why is it critical to match the size of the loading bucket with the capacity of the body?

DP: The key is optimising payload. With the right-sized excavator, a truck can be loaded in three to four passes, with is preferred. This is more accurate than using a larger excavator (and potentially filling in two passes) and makes filling to maximum payload each time more achievable - reducing wasted capacity each cycle.

Other variables are also relevant, for example, if the bench is too shallow, and a large excavator cannot dig 50 or 60-tonnes as required, then each bucket load will be light and again wasted capacity in the truck is the result. Mine managers and engineers are constantly measuring the payload of each bucket and improvements in capacity of 1-2pc are significant, so when our Ultima bodies deliver a 15pc improvement, the gains are massive.

AMR: What factors are relevant to reducing tipping turnaround time?

DP: The dump body needs to release the load efficiently with no hang-ups or carry-back. But we also have to be mindful that the body must not be too wide or have the headboard too high to fit into a maintenance bay. The type of steel treatment we use, the geometry of the floor and sides and the fact that we use smooth edges to stop initial catching of the load, all contribute to lower release angles and faster, complete tipping.

AMR: What does your advanced simulation software allow you to achieve and test in the design phase and does it provide greater accuracy and capacity when creating new solutions for different clients? For example, the heated body simulation for sub-zero applications and the 10°C maximum heat variation achieved from input to output.

DP: With regards to the software, the greater the volume of data we capture and analyse, the greater the accuracy of the simulation and efficiency of the final product. With so many years of experience, the number of bodies we have in testing around the world and the sheer quantity of data we have to draw on, we are able to create a simulation model of a new bucket in 10-14 days with between 99-99.3pc accuracy. With the exhaust heating of the body, required by some of our customers, we used advanced fluid dynamic modelling to analyse the exhaust gas flow from the time it enters the ducting in the tray to the time it exits. Our simulation revealed lower flow areas and the resultant hot spots they created. We were able to rectify these areas and even out the gas flow to achieve a total variation in temperature from start to finish of only 10°C.

AMR: Which specific areas of the body does your condition monitoring programme focus on and what is the nature and frequency of the resultant reporting you pass on to the client?

DP: Using real-time technology we are able to monitor and measure all arts of the body: floor; sidewalls and headboard. We plot trends in wear and only apply extra material where it is needed. This keeps the overall mass of the body down, while maintaining our original design specs. For example, if part of the floor should be 25mm thick but it has worn down to 10mm, we can put a 15mm plate on top to restore the original integrity but not exceed the original GVM of the truck.

This level of detail in our reporting allows the client to decide whether it is optimal to repair the tray or replace it at any stage in its service life.

AMR: Which truck chassis brands is the Ultima body available for at this time?

DP: The Ultima bodies are available for all OEM brands in the market today, so any truck 100t or larger.

Thanks to an enormous amount of experience, real world testing around the globe in a wide range of climates and environments and the use of cuttingedge software, Austin Engineering have created a range of Ultra Class bodies that are lighter, have the same service life and can carry larger payloads than typical OEM bodies.

That translates to custom solutions for each client, higher payloads for each truck in their fleet and lower cost per tonne. Just like modern body builders, the Ultima has the brains to match its brawn.