"Seo" system
Manufacturing process
Manufacturing Process:
The Space Frame manufacturing process at LANIK is as follows. A large part of the constituents are acquired from specialized manufacturers in the neighbourhood, since LANIK is located in one of the major metalworking centers in Spain. So, materials normally purchased by LANIK include tubes, cones, bolts, caps and spherical joints.
The manufacturing process peculiar to LANIK consists in the following basic operations:
a) Manufacturing of bars.-
- Machining of cones.
- Assembly of bar ends.
- Cutting of tubes.
- Welding of tubes with cones.
- Painting and oven-curing of bars.
- Classification and preparation for shipment.
b) Manufacturing of spherical joints.-
- Machining: drilling and threading of holes.
- Surface preparation and painting.
- Classification and preparation for shipment.
As special feature of the bar manufacturing process, it is worth mentioning that welding is performed only after the bar ends had been positioned on the movable bed of the welding machine. The positions of the end bolts are determined as a function of this positioning instead of as a function of the accumulated dimensions of the intermediate parts: bolts, cones and tube. This procedure prevents the accumulation of dimensional errors and allows very close tolerance margins for the construction of bars which are practically those resulting from the dispersion of the welding process.
In any case, welding can be performed by means of one of the following methods:
a) Semi-automatic welding on adjustable speed rotating tables with direct intervention of the welder. The welders as well as the process are homologated by a formally qualified organisation.
b) Automatic gas-shielded welding. The welding installation used is provided with a numerical control monitored positioner that automatically determines the real bar length and whose sequence can be established from the computer listings. The machine numerical control allows to store up to 50 different sizes concurrently.
Both bar manufacturing systems permit to achieve a size tolerance of + 0.5 mm. for normal size bars, that is usual practice at LANIK.
As for the machining of the spherical joint threaded holes, they are worked out by a robot specially designed and constructed for LANIK.
The equipment can be programmed manually, but normally it operates as an integral part of a CAD-CAM system, so that the design central computer that carries out the analysis and design of each space grid prepares the magnetic tapes conveying the information. As a final step of the analysis, the programme determines the lists of materials, bars and spherical joints, in the form of magnetic tapes, using a language readable by the manufacturing machines NC.