Folding machine or Folder is a very basic machine for HVAC ductworks.
It is used to fold sheet metal and also used for making air duct and fittings manual.
Standard capability is 1.5mm*1300mm, 1.5mm*1500mm, 1.0mm*2000mm, 1.0mm*2500mm….(Taken pneumatic folding machine as an example!)
Frame of Preda Machine Folding machine is made of steel welded construction with single bladed available for different sizes of sheets to be folded. A heavy duty welded steel frame with strong top and bottom beam makes the machine very strong and good for long using life.

Judging by the folding blades, there are two version which is normal folding machine and TDF folding machine.

A normal folding machine folds all kinds of flat plates like galvanized steel sheet, stainless steel sheet, Aluminum steel sheet and etc.

While a TDF folding machine or folder is capable of plates with TDF flange on it! So normally TDF Folders are used together with TDF Flange formers. It has slots on the bottom bed in which the formed flange lies during folding operation process. With this machine you can make L profiles or fully wrap around duct-work as per your needs. Generally it is a perfect companion to TDF Flange Former!

If judging by the power source, it can be classified into below two versions, manual folder/hand folding machine and Pneumatic folder!
A hand folder is specially designed for easy duct-work. It is easy control so that different folding angles can be achieved manually . Different work-pieces can be processed according to different requirements . It is suitable for duct forming , mental box forming and pan forming as well; It is light and easy to move and can be taken to the construction site due to relatively lighter weight.

A pneumatic folder adopts 4-pneumatic-cylinder as the power source driven by 0.6Mpa air pressure. Two cylinders of the four are used for folding when the other two are used for pressing the plates. It works stably without electricity by just connecting the air pump. The worker can operate the upper die up down and folding and releasing by controlling foot pedal. The max. folding thickness of Preda Machine pneumatic folder is 1.5 mm, which also depends of the plate width. For example, a 1300mm or 1500mm pneumatic folding machine is capable of max. 1.5mm with no problem, but a 2000mm or 2500mm version would capable max. 1.0mm!  Of course a pneumatic folder has two versions also, which are normal folder and TDF pneumatic folding machine. If you only want to bend flat sheet, the pneumatic flat sheet folding machine would be just fine. You have to choose pneumatic TDF flange sheet folding machine if you need to bend TDF sheet. As an efficient equipment for folding TDF flange duct sheet metal, this machine can be customized according to customers' requirement. As part of rectangular HVAC duct forming machines, the pneumatic TDF folding machine can be used with other rectangular duct forming machines such as cut to length line, TDF flange forming machine, Pittsburgh lock former, lock seaming machine, electric shearing machine and etc.