Skidding systems

Lifting a heavy load is one problem; moving it sideways is another. A skidding system solves the second: it slides a heavy structure along a track to where it needs to be, at controlled speed and to the millimetre, without a crane lift. Our skidding engineering is our jacking system turned on its side, the same hydraulic load-holding discipline, applied to horizontal movement. The load rides on our pallet system, hauled along rail beams by a self-propelling cylinder that grips the rail and walks itself along, a stroke at a time.

It is not a vertical-only capability. Our jacking and heavy-load manipulation engineering moves loads in X, Y and Z and members of our team led the design of a walking jack-up barge that combines jacking and skidding to walk itself across the seabed (a concept now also used to work through the surf zone in coastal mining). The same building blocks, jack, grip, slide, hold, recombine for each job.

Where we apply it

• Skidding heavy structures – repositioning loads of hundreds of tonnes – we have skidded a 900 t structure – along a track, including inclined tracks with runaway protection and in a seaway with uplift restraint and hydraulic preload to keep the connection tight.
• Mode-change systems – sliding a tower or spread between working positions on a single platform. On our geotechnical marine drill range a pallet shifts the tower between subsea drill, subsea CPT and seabed-frame deployment – no re-rigging between modes.
• Rack-and-pinion sliding doors – powered sliding for heavy moonpool doors, shaft doors and other large moving panels, where a rack-and-pinion drive gives controlled, repeatable travel under load.
• Two-axis (XY) movement – running one track across another to position a load anywhere on a deck or work area.
• Walking & self-propelling structures – combining jacking and skidding so a structure can reposition itself, drawing on our team’s walking-jack-up heritage.

Because we engineer the cylinders, the pin-and-hole indexing, the load-holding hydraulics and the structure together, the system arrives proven and controllable, not a set of parts to make work on site.