Pick-and-Carry With a Boom Truck
A contractor needs to move a 2,000 lb skid-mounted pump about 60 ft across a gravel yard because the truck cannot get closer to the pad. The operator plans to pick the pump with a 30-ton boom truck, keep it about 4 ft off the ground, boom centered over the rear, and travel slowly without outriggers deployed. At the 12-ft pick radius the stationary chart shows 7,500 lb. The route crosses a slight crown, a drainage swale, and an area where a plate compactor was used yesterday. A helper will walk beside the load and hold a tag line. The operator says the load is only 27% of chart capacity, so travel should be fine. The owner's manual is in the cab but has not been reviewed. The yard has no marked pedestrian controls.
1. Does the stationary chart capacity authorize this pick-and-carry? Explain what must be checked.
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No. A stationary capacity chart tells you what the crane can hold at a radius while set up; it does not authorize travel with a suspended load. Before any pick-and-carry, check the manufacturer's operator manual for a travel rating or an explicit pick-and-carry chart, and for the required configuration such as boom centered, load height, outriggers stowed, tire pressure, speed, and grade. The 27% figure is irrelevant if the machine has no travel-with-load rating. The manual must be reviewed before the move.
2. If the manufacturer does allow travel with a load, what conditions and route checks apply?
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If the manual permits travel: use the travel capacity at the actual radius and boom length; keep the load as low as practical and the boom centered; use a spotter; inspect the route for crown, swale, soft gravel, and uncompacted fill; maintain slow speed with no sudden starts, stops, or swings; check tire condition and pressure; stay within the manual's slope and cross-slope limits; keep personnel out from under and beside the load path; and stop if the load begins to swing or the crane becomes unstable.
3. If travel with a suspended load is not permitted, what alternatives would you propose?
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If travel with a suspended load is not permitted, use a machine designed for pick-and-carry, such as a rough-terrain crane with a travel chart, a telehandler, or a forklift; move the pump on rollers or a pallet jack; reposition the truck closer by improving access; or disassemble the pump into smaller loads. Do not use the boom truck as a carry crane just because the stationary chart has margin.