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Quality Problems and Inspection Key Points of Steel Fire Door

Release time:

2020-01-06 13:43

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Quality Problems and Inspection Key Points of Steel Fire Door

I through in recent years on the steel fire door production and engineering site management acceptance experience, in the construction and use of the field often appear the following quality problems:

1, raw material problems: the actual use of raw materials and design or testing materials do not match. Such as steel plate with thin plate instead of thick plate, cold rolling instead of galvanized, fire insulation materials are not filled, or honeycomb cardboard, rock wool instead of aluminum silicate fiber cotton or filling dissatisfaction, shoddy, reduce its production costs. The focus of the inspection is to compare the contents of the technical requirements in the inspection report and fill materials: one method is to knock on the sound inspection method. The stuffy sound indicates that there is filler in the door frame and door leaf, and the more stuffy it indicates that the filling is more real. Another method is the gap inspection method, that is, check from the holes of the door frame and door leaf (hinge hole, lock hole, bolt hole, door closer sequencer fixing hole, upper and lower vent holes, process hole, etc.). At present, the fillers for Class A and Class B fire doors sold on the market are white aluminum silicate fiber cotton (different bulk density, Class A is above 200kg/m3, Class B is above 160kg/m3), and Class C is yellow rock wool.

2, the thickness of the door leaf: the actual use of the door leaf in the project site is generally smaller than the thickness of the door leaf at the time of design or testing, and it is difficult to achieve the fire rating required by the building. Check whether the actual thickness of the door leaf conforms to the thickness of the door leaf in the test report.

3, fireproof glass problem: the project site often found with float glass (single or double), insulating glass, grade is not enough thin fireproof glass or lighting is not good, the number of bubbles exceed the standard fireproof glass posing as high fire-resistant glass. During the inspection, a piece of glass can be randomly removed to check whether the seal filled with fireproof liquid is at the upper end corner of the glass, and its thickness is measured. Grade A is generally 30mm, Grade B is generally 25mm, and Grade C is generally 20mm. Specifically, the data on the fireproof glass inspection report should be compared.

4, the problem of automatic closing: the project site is usually installed on the fire door closer and sequencer, and some even only install the door closer, its purpose is to automatically close when the fire door is opened. Theoretically speaking, there should be no problem in doing so. Once a fire occurs, people's consciousness will be flustered when escaping, resulting in uncertain opening force when passing through the fire door. Once the opening angle of the fire door is greater than the safe use angle of the door closer, the door closer cannot be reset. In this way, the fire door can not play its due role. There are 105o and 135o door closers commonly used in engineering. Check whether a door stop device is installed within the range of 135o when the door leaf is opened to eliminate the possibility of door closer failure.

5. Signal feedback problem: A common practice in the engineering site is to install only door closers and sequencers, and there is no signal feedback function according to the specifications. At this time, the fire door is also imperfect. The correct method should be that the fire door can be opened and closed normally. In the event of a fire, the feedback signal of the fire alarm system in the fire control room can be transmitted to the releaser, so that the releaser can switch and the fire door can be automatically closed. The inspection method is very simple, as long as the repeated test of its linkage action → feedback to the fire control center.

6, the problem of escape locks: the project site often found in the crowded emergency evacuation port using ordinary pressure to fire lock, but not the use of special escape locks. The special escape lock can open the door simply by touching the body when the personnel escape. Even when there is a fire, when people are crowded at the door, the fire door can be opened to achieve the purpose of escape. Check whether this special lock and flexibility are used. Under normal circumstances, the emergency evacuation escape door is not allowed to open the door from the outside frequently, and the lower sill above the ground cannot be set to prevent the escape personnel from being tripped during emergency evacuation.

7. Problems with door gaps and sealing rubber strips: Due to the shoddy manufacture of products of individual enterprises or lax quality control in the installation process, the widths of various gaps such as door leaf and door leaf interface gaps, frame gaps, door leaves and the ground gaps seriously exceed the standard, and the technical requirements stipulated in the standard cannot be met due to fire and smoke leakage during inspection. GBl2955-1991 5.3.3 in "General Technical Conditions for Steel Fire Doors" clearly requires that the upper seam shall not be greater than 3mm, the side seam shall not be greater than 4mm, the middle seam of double fans shall not be greater than 4mm, and the lower seam shall not be greater than 8mm. In addition, the sealing strip used on the fire door does not meet the fire prevention requirements at all. It is visually inspected that there are no small white spots of incombustible materials on the sealing strip, and it is touched with a lighter. What's more, the sealing strip is simply not installed, which seriously affects the fire prevention and smoke isolation function of the steel fire door.

All in all, the steel fire door must be strictly in accordance with the standard requirements of the process of production, in accordance with the requirements of the specification of rational use, supervision and management departments should also be from the production process until the scientific use of engineering, to ensure its good quality and reliability, only in this way, can really let the steel fire door play its due role.

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