The fact that steel joinery is a niche product does not mean that the range in itself is limited. Steel profiles are available for both traditional joinery and curtain walls, with or without thermal break, whether or not fire, bullet or burglar resistant, and in many shapes and sizes. What is limited, however, is the group of constructors capable of making effective high-quality windows and doors from those steel profiles. After all, editing the profiles is no easy task: it involves a considerable amount of manual work, requires the necessary investment in equipment and logistics, and requires explicit knowledge and experience.
There is a long way between the delivery of the profiles by the manufacturer and the installation of the windows and doors by the carpenter. Numerous requirements and aspects on this route complicate both the construction and the installation of the joinery.
STEP 1: SAW AND EDIT
Steel profiles (and associated glazing beads) are supplied as standard in lengths of 6 m and usually arrive completely unmachined at the constructor. In other words, it is the constructor who is responsible for all processing of the profiles. He must cut them to size and mill them based on the chosen fitting. In addition to the necessary precision, this also requires specialized equipment and an adapted studio design. The main aspects to be taken into account by the manufacturer are:
Machines: the machines for working steel are in principle no different from those before the processing of aluminum, although it is necessary to use suitable saw blades and milling machines drill heads.
Deformations: as there are considerable forces when cutting the steel profiles come and have a look, it must be ensured that under the influence of these forces no (minimal) deformations occur. Use of custom saw blocks - usually provided by the profile manufacturer - helps to avoid problems.
Workshop design: processing steel is not a clean job. So come milling and saw miniscule iron particles free that can settle on other materials. With stainless steel and aluminum, for example, can eventually lead to rust and damage. It is therefore of it is very important that steel is processed in a separate room - and with other machines - and that that room is equipped with a good smoke extraction system.
STEP 2: ASSEMBLING AND WELDING
If aluminum profiles are joined together using an angle iron and PVC profiles are mechanically welded together, the steel joinery is assembled by manually welding the different profiles together. It is a specialist and time-consuming work that must be carried out with the necessary caution and with an eye for detail.
Especially the grinding away of the welds, and possibly removing the slag, requires special attention. After all, only if this is done carefully, one obtains the completely smooth and solid result that is expected from steel joinery. Grinding the seams too far also has a negative effect: this way pits are created that remain visible even after sandblasting and painting.
STEP 3: SANDBLASTING, METALLIZATION AND POWDER COATING
A second crucial step in the assembly of steel joinery is the powder coating of the profiles. If the profiles for aluminum joinery are always pre-painted and separately, this will be done at steel joinery only after all operations have been carried out and the window and / or door frames be fully assembled. The whole is first sandblasted, then metallized and finally powder coated.
Again, a number of factors play a complicating role here:
Dimensions: since the joinery is lacquered as a whole, one has to do with both transport as well as in terms of furnace taking into account the final dimensions of the elements. Not however, all powder coating companies are capable of handling large elements and one can significant additional costs are involved;
Adjustments: as soon as the elements have been painted, no further processing is allowed in principle the profiles are executed. Metallizing and painting the elements takes care of it for the necessary protection of the profiles. There will be penetrations afterwards once done, there is, certainly on the exterior side of the profile, a risk of moisture infiltration and rust;
Errors: do errors occur when painting the joinery - irregularities, a wrong one color… - then the solution consists in sandblasting, metallizing and again lacquering.
STEP 4: TRANSPORT AND PLACEMENT
When transporting and installing steel joinery, dimensions and weight again apply as the main complicating factors. Steel windows weigh on average three times as much as others systems, which makes cranes and rolling stock indispensable for assembly.
Reference:
• http://projecto.pmg.be/
• 27 march 2020
• by Elise Noyez