Synergistic Relationship Between the Pressure Relief Function of the Pressure Relief Door Body and the Interlock System
Many purchasers tend to confuse the pressure relief function and the interlock isolation function. These are two independent yet coordinated safety systems.
Working Principle of Pressure Relief Door's Intrinsic Pressure Relief Function
In the event of indoor deflagration, once the pressure exceeds the preset relief threshold (normally 30~50kPa), the shear bolts for pressure relief will fracture and dedicated hinges will disengage. The door leaf swings outward instantly to discharge overpressure gas rapidly. This reduces the shockwave load imposed on building walls, beams and columns, preventing collapse of the main structural frame. For models equipped with gravity door closers, the door can automatically close and reseal after pressure relief is completed.
Auxiliary Effect of the Interlock System During Explosion
Under normal closed status, the interlock mechanism firmly latches both doors to ensure airtightness of the buffer airlock chamber. Explosion shockwaves can only be vented outward directionally through the pressure relief door, avoiding backflow into rear rooms via personnel access passages. Without interlock control, simultaneous opening of both doors would create a straight-through channel for blast waves, rendering the blast-resistant structure completely ineffective.
Mechanical Operation Principle
Adopt stroke hard limit mutual exclusion logic; the physical structure mechanically prevents simultaneous unlocking of the two doors:
1.Opening Outer Door A Rotation of the door handle drives the transmission connecting rod to push the limit shifting fork, which clamps the latch bolt transmission mechanism of Inner Door B. Under this state, Inner Door B cannot be unlocked or opened either by the internal handle or key.
2.Opening Inner Door B The internal operating connecting rod lifts the interlock stop block to directly lock the closing stroke of Outer Door A, making the outer door impossible to open from outside.
3.Reset Unlocking Rule Only when the opened leaf is fully closed and the latch bolt retracts completely to trigger the reset of the shifting fork, can the unlocking authority of the other door be released
