There are mainly two kinds of flange systems of duct connection. American standard and European standard, which is TDF flange recommended by SMACNA association and TTF/LT mate flange as well as improved GDF flange recommended by British Refrigeration Association. Comifo knows flange structure very well, and quite familiar with the standards of duct pressure test and leakage test, including SMACNA, DW144/142, GB50243-97 standards. Comifo flange forming machine can satisfy different requirements in different markets.
Comifo flange machine adopts heavy duty underpan, arc welding frame, high grade motor, high precision bearing, thermal refined and grinded roll shafts. Its reliable transmission system is free of maintenance. The surface panels have been spray painted.
European standards recommended the use of slide-on flange because of its strength, hollow double section and the ability to hide the L’ type corner pieces. GDF integrated flange is widely applied in Europe as a kind of quick installation duct flange. It shares common advantages with TDF flange—well seal, free of jointing and rivet. GDF flange is integrated with duct, connect with 4 bolts and special duct corner and clamp. One side forms GDF flange the other forms clip. Or roll forming both GDF flanges in one machine as different model numbers.
Comifo 
Helen Lin