What are the functions of an explosion-proof door?
An explosion-proof door is an explosion-protection device designed to withstand accidental explosions of external equipment in industrial buildings, thereby ensuring the safety of personnel and the integrity of internal equipment, mitigating the impact of blast waves, and effectively preventing further damage caused by the explosion. So, what are the functions of an explosion-proof door?

What are the functions of an explosion-proof door?

1. Explosion-proof doors are designed to withstand accidental explosions of external equipment in industrial plants, thereby ensuring the safety of personnel and the integrity of internal plant equipment by protecting them from the damaging effects of blast waves. They effectively prevent the escalation of explosion hazards. These doors are fabricated from specialized industrial steel plates according to rigorously defined mechanical specifications and are equipped with high-performance hardware fittings, making them both practical and aesthetically pleasing while safeguarding lives and property. Explosion-proof doors are also referred to as blast-resistant doors.
2. In the event of an explosion, the incident pressure and reflected pressure should be predicted and set accordingly. The blast-resistant door must be capable of withstanding blast pressures within this range to achieve the required protective performance, thereby preventing casualties and property damage.
3. After an explosion, the blast-resistant door can still be used normally even if the preset blast resistance is not fully achieved.
4. In the event of an explosion, the explosive force can be set to a predetermined level, causing deformation; however, the door components remain functional, preventing people from being trapped or the passage from becoming blocked.
5. Essential containment isolation features prevent direct air exchange between the isolated space and the external environment, thereby reducing external contamination of the containment protection space.
6. Explosion-proof doors are safety devices equipped with self-destruct and emergency escape functions.

What types of explosion-proof doors are there?

1. Common types of explosion-relief doors used in boilers include rotary-type and diaphragm-type designs. The rotary-type explosion-relief door is a self-sealing device that relies on its own weight for closure; it is typically constructed from cast iron, with the door cover coated with heat-resistant concrete. A key feature of this type is its automatic reset: if the moment generated by the explosive pressure of gases within the furnace or flue exceeds the moment produced by the door’s own weight about the central axis, the door will open; conversely, if the pressure is insufficient, the door will automatically close again. Rotary explosion-relief doors are generally mounted on the walls of the combustion chamber and can be classified as either vertical or inclined, depending on their tilt angle relative to the vertical. For inclined rotary explosion-relief doors, the tilt angle usually does not exceed 30 degrees.
2. Explosion-proof doors with rupture membranes consist of a rupture membrane and a clamping mechanism. When an explosion occurs in the combustion chamber, the resulting pressure ruptures the membrane, thereby relieving excess pressure. Common rupture materials include asbestos, aluminum, copper, and other non-ferrous metals; the specific material is selected based on pressure and temperature conditions. Currently, asbestos-cement boards are widely used, and such rupture-membrane explosion-proof doors are frequently installed on flue ducts.

What are the requirements for explosion-proof doors?

1. Explosion-proof doors shall be installed in the combustion chamber, at the furnace outlet, in the economizer flue, in the flue upstream of the induced-draft fan, in the horizontal flue downstream of the induced-draft fan, or in any flue with a slope greater than 30°.
2. Explosion-proof doors shall be installed in locations that do not pose a threat to the safety of operating personnel and shall be equipped with pressure-relief ducts; flammable and explosive materials shall not be stored in the vicinity.
3. The emergency explosion-proof door must be manually tested on a regular basis to prevent rusting.