The convection coils use for gas cracking on petroleum industries. Cracking, in petroleum refining, the process by which heavy hydrocarbon molecules are broken up into lighter molecules by means of heat and usually pressure and sometimes catalysts. Cracking is the most important process for the commercial production of gasoline and diesel fuel.

For Karun Petrochemical Company 6 modules of convection coils have been fabricated by AAC. These module are series and hot gas flows in to the coils on top and exit on the bottom.