Capital Equipment News August 2017

WHEEL LOADERS

Bell wheel loaders are direct drive vehicles with an automatic transmission and torque converter.

of job conditions includes the assessment of desired productivity, material densities, working hours, type of ground, dump heights and ramps, among other things. “It gives you the needed info for a proper machine sizing, which always starts with the key metric of a wheel loader: its payload. A proper payload choice guarantees the desired productivity and optimised costs,” says Torres. McNeil says to know the right sized machine, one needs to calculate what size of wheel loader is going to deliver the most productivity with the least idling time for a particular operation. But, how best do you get this right? Brandauer says a number of factors need to be considered. These include required capacity per day/shift/month; material filling factor of the bucket; loading cycle (distance/ time); working hours per day/shift/month; idle time/breaks per day/shift/month; material density; and average speed of the wheel loader. “With these figures you can calculate the right size of the bucket, which in turn allows you to choose the right sized wheel loader,” says Brandauer. According to Tuntland, one of the most effective ways of sizing a wheel loader or any loading tool is through a site assessment. “Caterpillar and its dealers are equipped with system application specialists that can perform this assessment. For existing sites, it is very important to measure the ‘as is’ production capabilities. This is done by capturing various parameters from the site: cycle times, payloads, fuel burn, production per hour, haul road profiles, among others,” he says. “Once this is complete, data can be compared with production targets.” Additionally Caterpillar has the capability to run “to be” scenarios in its own software tool by changing parameters: loading tools, hauling units and even haul roads. Schmitt also believes sizing the machine plays a big role. He says there is need to consider the conditions on site. “For sure, the productivity requirements for bucket size and cycle time play a major role. However, you also need to consider matching the equipment to avoid any losses in the production process, for example, due to a long loading time or

CASE´s wheel loader technology has five effective electronic systems to increase machine efficiency.

less rpm to get the same output on torque as on a wheel loader with torque conver ter. Less rpm means less fuel consumption,” says Brandauer. McNeill says hydrostatically driven machines are generally deemed to provide better fuel efficiency advantages, but the customer pays for this with the higher capital cost, as well as repair and maintenance costs associated with the machines. “Bell wheel loaders are direct drive vehicles with an automatic transmission and torque converter. They deliver similar fuel efficiency, because it is not only the drive that impacts this, but are less complex and less costly to maintain, while being suited to all applications,” says Brandauer. According to Tuntland, overall configuration is very important when it comes to efficiency. “Just to name a few: ride control, axle oil cooler, standard lift or high lift, bucket, tyres, all have a significant impact on fuel efficiency. As you can imagine anything that slows down production will in turn decrease efficiency. Factors such as ride quality, reach, dump clearance and stability, can all have an impact on production. It’s very important that the machine is configured correctly for the application,” he says.

idling of the hauling units in the supply chain,” he says. He also believes that the daily schedule also plays a role. “Often you see during rush hours a queue of customer trucks waiting to be loaded – if it takes too long you may disturb the job site.” Schmitt adds that the most common reason for high costs per tonne are oversized machines versus the required production output. Oversized machines have a higher initial purchase price, higher running costs and usually also higher idling times. “The Volvo SiteSimulation software helps to select and define the right machine for the production targets and or hauling units. Volvo SiteSimulation makes it possible to provide different scenarios and makes efficiency gains immediately visible,” says Schmitt. Fuel efficiency Fuel efficiency is always one of the key considerations when choosing any piece of equipment for the job at hand. While fuel efficiency is achieved through a number of initiatives, the choice of a wheel loader’s driveline plays a bigger role in the overall efficiency. “The choice of the driveline is very important for fuel efficiency. With Liebherr’s hydrostatic driveline you need

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