What is a spool?

Why spools

Welding in a workshop takes place under controlled conditions: with fixtures, in a good welding position and with inspection close by. On site only the connections between the spools remain: field welds or flange joints. This reduces the work at height and in confined spaces.

How a line is divided into spools

The division depends on:

• transport: the length, width and height that fit on a truck and through doors or shafts;
• the weight that can be lifted on site;
• installation: a spool must be able to reach its place, often with a loose flange or a field weld with extra length to absorb tolerances;
• surface treatment and testing, such as galvanising or a pressure test per spool.

The spool drawing

A spool drawing is an isometric drawing of one spool. It shows the spool number, all dimensions, the weld numbers, the difference between shop welds and field welds, and the bill of materials of that spool.

Progress per spool

On site, progress is often followed per spool: fabricated, delivered, installed and tested. Together with the weld list, this shows which part of a line is ready.

In FlowCAD3D

Isometric drawings per spool, weld registration with a weld list, and Site progress per spool, weld and line, from planned to tested or approved, with photos and export to Excel. A first version of the automatic spool division (prototype) proposes a division that the work preparer checks. More: Spool drawings for prefabrication.