Engineering Door The airtight doors are divided into two types: flat open airtight doors and push-pull airtight doors.Electric push-pull airtight door is mainly composed by transmission device, mounting bracket, upper rail, door leaf parts, cover system, wheel bearing, sealing system, lower rail system, the guide wheel, clutch, nameplates and warning signs.The front and rear of the door is filled with 50mm alkali - free centrifugal glass fiber cotton for heat preservation.In the closed state, the airtight ring filled with 0.16MPa dry clean oil-free air and the door should be close fit, do聽light-leaking inspection to ensure the gap without leakage.Engineering Door website:http://www.nesbuilding.com/engineering-door/