The purpose of stainless steel manhole flange!

The stainless steel manhole is a safety emergency ventilation device installed on the top of the storage tank. It is usually used in conjunction with a fire extinguisher and a mechanical breathing valve. It can not only avoid sudden overpressure or vacuum in the tank due to unexpected reasons, damage the storage tank and cause accidents. It also plays the role of safety and fire resistance. It is a safety device to protect the storage tank. It is especially suitable for the vaulted atmospheric tank whose storage material is capped with nitrogen. It has the advantages of constant pressure discharge, constant pressure suction, flexible opening and closing, safe fire resistance, compact structure, good sealing performance, safety and reliability.  
Stainless steel manholes are generally made of 304, 316L steel plates as raw materials.