Travelling Loaded on a Wet Slope
You must move the 180° excavator 120 m across a site to a new dig face. The route crosses a 12° slope that is wet and has a 1 m deep drainage ditch at the bottom. The machine has a full bucket of spoil in the front bucket and the boom is raised for travel. The tracks are parallel to the slope contour. A colleague suggests travelling down the slope with the load to save time. The site speed limit is 8 km/h and there are pedestrians near the bottom of the slope.
1. How should the machine be configured and positioned for this move, and why?
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Before travelling: empty the bucket (do not travel with a loaded bucket on a slope - it raises the centre of gravity and increases the overturning moment), lower the boom to a safe travel height, keep the bucket close in, and select the correct travel mode. On a slope, travel with the boom/bucket on the uphill side and the tracks in line with the direction of travel (up/down the slope), not across it. Travelling across a 12° wet slope with tracks parallel to the contour increases the risk of sliding and rollover. Keep speed low, use low range, and avoid sudden steering or braking. The ditch at the bottom is an obstacle: approach it square-on, at low speed, and do not attempt to cross with a raised load.
2. Your colleague wants to travel downhill with the load. What is your response and what is the stability reasoning?
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Refuse that configuration. Travelling downhill with a loaded bucket puts the load forward and downhill, moving the centre of gravity toward the lower edge and increasing the overturning moment in the direction of travel; on a wet 12° slope this is a rollover risk. The safe practice is to travel with the heavy end (boom/bucket) uphill and the load kept low and close, or to empty the bucket first. If the machine must descend, it should be with the bucket trailing on the uphill side, low, at low speed, and with the route checked for grip. Saving time does not justify an unstable configuration.
3. What site controls should be in place before you start the move, given pedestrians near the bottom of the slope?
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Plan the route and check it for soft ground, ruts, and the ditch crossing; agree a exclusion zone at the bottom of the slope so pedestrians are not in the machine's path or in the run-off area; use a banksman if visibility is restricted or the route is shared; ensure the travel alarm and horn work; keep to the 8 km/h limit and lower where conditions demand; and confirm the ditch is crossable (or find another route) before committing. The move should be treated as a planned operation, not an ad hoc drive.