Get More Wheel Loader Productivity

Make sure that your wheel loader is properly matched up in size with other equipment, such as hoppers or dump trucks, that it will be working with. Generally speaking, the production required of a wheel loader should be slightly greater than the production capability of the other critical units in the earth or material moving system. For example, if a hopper can handle 300 tons per hour (272 metric tons), then your loader should be capable of moving slightly more than 300 tons per hour (272 metric tons).

You can use these six simple steps to make sure your machine is properly matched up to your application:

1. Determine production required or desired.

2. Determine loader cycle time and cycles per hour. Remember that machine size must be assumed to select a basic cycle time.

3. Determine required payload per cycle in loose cubic yards and pounds (meters and kilograms).

4. Determine bucket size needed.

5. Make machine selection using bucket size and payload as criteria to meet production requirements.

6. Compare the loader cycle time used in calculations to the cycle time of the machine selected. If there is a difference, rework the process beginning at the second step above.

When hauling loose granular material on a hard smooth operating surface, an average of 27 to 33 seconds for basic cycle time is considered reasonable for Cat loaders with a competent operator. This includes load, dump, four reversals of direction, full cycle of hydraulics and minimum travel distances.

Remember that different material types, pile heights and other factors may improve or reduce wheel loader production. So you’ll need to carefully consider these variables and either add to or subtract them from your basic cycle time number when applicable.

When hauls are involved:

1. Obtain information about the haul and return portion of the cycle by consulting your Cat dealer.

2. Next, add the haul and return times to the estimated basic cycle time to obtain total cycle time. 

3. But remember that variations on this time should be anticipated in the field. 

Job efficiency is an important factor in wheel loader machine selection, because this number tells you the actual number of minutes worked during an hour, including variables such as bathroom breaks and other work interruptions. 

To calculate your wheel loader’s job efficiency number, use this formula:

Cycles per hour at 50 minutes per hour (83% efficiency)

= 

Cycles per hour at 100% efficiency

×

50 minutes actual work time per hour

Your Cat dealer can help you identify average loader cycle times. One useful calculation is your loader’s required payload per cycle. Get that number by dividing your required hourly production by the number of cycles per hour. 

Now, make sure you have the correct configuration and capacity for the bucket on the front end of your loader.

To do this, take your required payload per cycle number and then divide the payload by the loose cubic yard (cubic meter) material weight. This will tell you the number of loose cubic yards (cubic meters) required per cycle.

Bear in mind that the bulk of material handled does not weigh 3,000 pounds per cubic yard (1,800 kg/m3), so you’ll need to have reasonable knowledge of material weight being handled to accurately estimate your production. 

The tables section in your wheel loader's Operation and Maintenance Manual lists average weights for certain materials when actual weights are not known to help guide you. 

The percentage of rated capacity a bucket carries in various materials is estimated in the chart below. The bucket size required to handle the required volume per cycle is found with the aid of the percentage of rated bucket capacity, called bucket fill factor.

The bucket size needed is determined by dividing loose cubic yards (cubic meters) required per cycle by the bucket fill factor.

The basic bucket fill factor formula is:

Volume required/cycle 

Bucket size = _____________________________

Bucket fill factor

Your bucket fill factor is the approximate amount of material, as a percent of rated bucket capacity, which will be delivered per bucket cycle. Fill factors on wheel loaders are affected by bucket penetration, breakout force, rack back angle, bucket profile and ground engaging tools (GET) such as bucket teeth or bolt-on replaceable cutting edges — all of which have a direct bearing on the machine’s performance.

Learn more about optimizing your wheel loader’s performance and productivity.