Fabrication and the fabricator's premises
Fabrication consists of cutting pieces of steel and connecting them together.
The material is generally obtained from rolling mills or stockists in the form of I sections, channels, hollow sections, angles or plate. The steel specified should be rationalized to use relatively few section sizes and a common grade. The sections have to be cut to length, drilled and welded as necessary ready for assembly, and in most cases some protective treatment will be applied against corrosion. Operations can include cleaning, sawing, shearing, punching, grinding, bending, drilling, welding and the finishing of the steel. These involve extensive use of numerically controlled processes which improve productivity and quality. All such operations come under the heading of fabrication.
Fabrication yards have facilities for storage, processing and dispatch.
Fabrication is, in effect, a factory process, with facilities for receiving steel from rolling mills, storing it in the steel yard, processing it as required (e.g. cutting, drilling, welding, painting), and loading up the prepared material for transporting to the building site.
It may involve cranes for moving material within the factory, but the use of mechanical conveyors is more efficient. .
There will be saws and guillotines, drills and punches, and facilities for flame cutting and welding, both by hand and by machine.
The type of work a fabricator is able to carry out depends on size, equipment and facilities, which can vary widely.
Fabricator's shops vary both in the size of the facility and weight of material that they can handle. The sophistication of the available equipment will also vary. Increasingly, where investment is available, operations are being automated and computer-controlled.
Fabricators facilities may range from a very small operation, through to a large factory involving many departments responsible for material procurement, material allocation, drawing office, planning, welding, quality control, stockyard, preparation, fabrication, treatment, storage and dispatch. Fabrication may also involve a number of fabrication shops each resourced with different cranes, welding and other equipment to suit different product ranges.
In addition to the shop floor for the main production areas, areas may be set aside for the trial assembly of certain elements. The remainder of the fabricator's premises will usually include design and drawing offices, a template shop, planning, administrative and estimating departments.
Materials can be ordered direct from the producer where significant quantities of steel are required; smaller quantities of a limited range of sections can be obtained from stockholders.
Steel products are only sourced direct from the rolling mill if the quantity of a given size and grade is sufficient. Otherwise they are sourced through steel stockholders who offer a wide range of "off-the-shelf" profiles. As these are generally in standard lengths there may be some additional cutting wastage, but a steelwork contractor may have a long-term partnering arrangement with a stockholder whereby:
- The stockholder takes the risk of cutting wastage by delivering materials that are cut-to-length.
- The materials are delivered to the fabrication works on a "just-in-time" basis to reduce the steelwork contractors need for working capital.
- The materials may be pre-treated or pre-prepared in other ways (eg plates profiled and drilled).
