Project · Mechanical installation and welding · Industrial

Large-bore pipe replacement

Large-bore pipework replaced inside an existing plant. We prefabricated the spools, rigged them into position on chain hoists off the plant steel, and welded them in place.

The new run in place.

Scope

Mechanical installation and welding · Industrial

Setting

Existing plant, scaffolded work fronts

Plates

5 photographs, 4 stages

How it was built

One plate to a stage. Press a plate to open it full size.

Stage 01 / 04

We put the covers down before anything hot starts — blankets under the work front, sheeting across what is behind it, and the grating below closed off. A spark that goes through the grating lands on whatever is on the level under you.

The work front covered before hot work starts.
Stage 02 / 04

Branches and stubs go on at floor level, where the piece can be turned and the weld is made in the flat position. The spool goes up as one piece with its openings already in it. Every branch done down here is one less weld made overhead.

Branch and stub welded on before the spool goes up.
Stage 03 / 04

There is no crane over the work front, so the load comes off the plant steel. We agree the attachment points with the plant first, then hang beam clamps and chain hoists at each end and walk the spool into line by hand.

Beam clamps and chain hoists off the existing steel.
Stage 04 / 04

Fit-up decides the joint. We set the gap and hold it the whole way round before an arc is struck, and the root goes in first — in this frame it is part way round, with the gap above still open. The joint is cleaned and checked before the fill and cap go on.

The root run part way round the joint.

Disciplines on this job

Send us the drawings.

Send the drawings or the scope and we will come back with a price and crew dates. If it is a shutdown, tell us the window.

Send us the drawings