Work on a Flat Bench

Ensuring that your loading tools operate off a flat bench wherever possible will increase productivity. Some thoughts from the field.

Overview

While it is sometimes necessary to work on a slope (e.g. putting in a drop-cut), the practice should be avoided wherever possible.

Working wheel loaders, hydraulic excavators or shovels on a bench that is not level has three potential issues:

• Increased safety risk.
• Reduced productivity.
• Higher maintenance costs.

Safety Risk

When you work a wheel loader on a slope, you run the risk of it falling over. The greater off-level you are, the more likelihood that something can go wrong. When it does, the result can be catastrophic.

While working off-level, a soft spot in the floor, accidentally running over a spilled rock or an inadvertent collision with a haul truck can put a machine on it’s side.

Working rotating machines such as shovels and excavators on a slope can also be problematic. A primary risk for the loading tool operator is the increased danger of hitting the truck while slewing up over the side. Working off-level greatly increases the risk of collision between loading tool and truck.

Reduced Productivity

Cycle times slow when you work off-level. A rotating machine is fighting gravity to not only lift the bucket, but increasingly so to slew it as well. Depending on the power of the slew circuits, this effect can be quite pronounced.

Wheel loader cycle time is impacted as a result of having to back up the slope and fight against gravity. Operation on a slope is generally slower as the operator takes more care in the difficult going.

Higher Maintenance Costs

Rotating machine costs can go up significantly where they are consistently worked on slopes. Slew bearing can experience abnormal wear and slew motors and brakes can suffer reduced life as a result of this practice.

Action Item(s)

1. If you need to use a loading tool on a slope, carry out a risk assessment of the application.
2. Where loading tools are continually operated on a slope, pay attention to increased maintenance requirements – eg slew brake wear

Summary

Take the time to ensure that you fully understand the implications of working loading tools on a slope. This is vital to ensure safe, productive and low cost operation.

This is part of an ongoing series of posts on the fundamentals of Load & Haul. If you like this post, please take the time to check out others in the series.