TECNA S.p.A., a company situated in Castel S. Pietro Terme (BO) - ITALY, has been working in the field of resistance welding since the beginning of the ‘70s. During these years it has become a well-known company specialized in the production of a vast range of spot and projection welding machines briefly listed hereafter: spot and projection bench welding machines 16-150 kVA single-phase linear action welding machines 35-315 kVA D.C. three-phase linear action welding machines 100-630 kVA automatic air operated suspended guns with built-in transformer 16-75 kVA production spot guns medium frequency 56-140 kVA, from 16 to 45 kA rocker-arm pedestal spot welders 12-50 kVA modular spot welders: twin spot, rocker arm, linear action spot welders for car body repair, portable and self-contained, hand and air operated, single and three-phase versions D.C., 2-20 kVA powers. Moreover, TECNA manufactures a line of products which can be considered “accessories” to the resistance welding machines: adaptive and digital welding control units, with microprocessor, ammeter, constant current and standard versions test and measurement instruments for resistance welding machines balancers from 0,4 to 180 kg. TECNA develops on the whole all its products boasting a high quality level. All the steps from the engineering, to the production, to the sales through different channels according to the final destination of the product, are carefully followed up. The main fields of interest go from the car body repair to the industry, including automotive industry, to the metal structural works.