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Offshore · Marine construction

Jack-Up Barges

Construction barges that stand on their own legs above the waves, so piles for jetties, platforms and bridges can be driven from a steady deck. We fabricate the steel that lifts them: legs, spud cans, jacking units, leg wells and pile manipulators.

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Allmarc 3D model · to scale
Explore the model

How it is built.

Scroll: the camera moves to each part in turn and ends on the exploded view. Drag to turn it round yourself.

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A barge on its legs

The barge floats to site, lowers its legs to the seabed and climbs them until the hull is clear of the waves. From there, a crane and a pile manipulator drive piles as if on land.

Scroll to see how it is built · drag to turn it round

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Legs

Four cylindrical legs, rolled from thick plate in sections, with pin holes on a set pitch up their length.

How is it possible at Allmarc?
Three-roll pinch cum pyramid plate rolls in the Allmarc works

Used here for: Legs

  • Rolls plate up to 40 mm
All our machinery

Used here for: Legs

  • Full-penetration welds on built-up sections
All our machinery

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Spud cans

Conical footings that spread each leg’s load into the seabed.

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Jacking units

At each leg, two yokes and four cylinders climb the barge up the leg, pin by pin. See Hydraulic Jacking Units.

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Leg wells

Wells through the hull with guide rings that keep each leg straight while it moves.

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Pile manipulator

A frame over the side that holds each pile plumb, or on its rake, while it is driven. See Pile Manipulators.

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Hull and crane

The hull, crane and hammer come from their makers.

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A kit of parts

Legs, cans, jacking units, wells and manipulator: every member numbered, match-marked and packed in erection sequence.

From our works

In our works: leg and jack-house base

A rolled leg section standing on its jack-house base: two ring decks with radial stiffeners, set up on a levelled plate so everything is square before welding.

A jack-up leg section standing on a stiffened ring base in the Allmarc works
Photos

In our works, and at sea.

Leg sections, yokes and jacking brackets in the bayVideo
A leg can on rotators, and its profile-cut stiffenersVideo
Why Allmarc

Experience you can trust.

We fabricate to your drawings and prove the fit in our own bay before anything ships. Open any line for the detail.

Talk to an engineer
Heavy rolled plate
  • Leg sections and yoke rings rolled from thick plate.
  • Seams welded on the submerged-arc line.
Round and true
  • Rings braced round while they are welded out.
  • Pin holes cut and checked to jig.
Fitted in the works
  • Yokes, guides and leg sections fitted together before dispatch.
  • A 30 m wide bay with 11.5 m under the hook.
To the designer’s drawings
  • Hydraulics, winches and cranes come from their makers.
  • We build the steel they work in.
Start a project

Have a drawing? Let us build it.

We fabricate to your design, from plate to a packed container. An engineer will tell you honestly how we would build it.

Send us a drawing