In the field of building fire protection,steel fire doors are crucial facilities for ensuring the evacuation of personnel and the safety of property.Among them,steel fire doors with cold-rolled steel frames and panels,boasting a 30-minute fire resistance integrity rating,have become an economical and efficient fire protection solution for low-and medium-risk areas,without incurring additional costs.
Cold-rolled steel:A Balance Between Performance and Cost
Cold-rolled steel sheets,through cold-working processes,enhance strength and surface precision,achieving a yield strength exceeding 235 MPa,far surpassing ordinary hot-rolled steel sheets.In steel fire doors,the door frame uses 1.2mm thick cold-rolled steel sheets,while the door panel uses 0.8mm thick cold-rolled steel sheets,meeting structural strength requirements while controlling costs through large-scale production.For example,a commercial complex project using cold-rolled steel fire doors reduced the cost per door by 40%compared to stainless steel doors of the same specifications,while fully meeting the 30-minute fire resistance standard.
Technical Implementation of 30-Minute Fire Resistance Integrity
The fire resistance performance of steel fire doors depends on the filling materials and structural design.The interior of the door leaf is filled with an intumescent fire-resistant and heat-insulating material(such as perlite or aluminum silicate fiber).Upon exposure to high temperatures,this material expands to form an insulation layer.Combined with the tight overlap of the cold-rolled steel frame and leaf,this ensures that the temperature of the unexposed surface does not exceed 140℃within 30 minutes.Experimental data shows that,using standard processes,the gap expansion at the overlap between the door leaf and frame of a cold-rolled steel fire door is≤2mm in a 30-minute fire resistance test,far below the national standard requirement of 4mm,effectively preventing the spread of flames and smoke.
Cost Advantages:Material Optimization and Process Standardization The cost advantage of cold-rolled steel fire doors stems from two aspects:firstly,the choice of materials—cold-rolled steel is only one-third the price of stainless steel and consumes less energy during processing;secondly,standardized processes—automated production lines enable mass production,reducing human error and material waste.For example,a residential project adopted a modular design,standardizing components such as the door frame,door leaf,and door closer,reducing the installation time of a single door to 30 minutes and lowering labor costs by 25%,without affecting fire resistance performance.
Application Scenarios:Ideal Choice for Low-to Medium-Risk Areas
30-minute fire-resistant steel fire doors are suitable for low-to medium-risk areas such as pipe shafts,cable shafts,and equipment rooms.They meet fire safety regulations while improving project cost-effectiveness through cost control.For example,in a hospital renovation project,cold-rolled steel fire doors replaced traditional wooden fire doors,resulting in improved fire resistance,a service life extended to over 10 years,and a 60%reduction in maintenance costs.
Cold-rolled steel fire doors with frames and sashes,characterized by”30-minute fire resistance integrity+zero cost increment,”provide an economical and reliable solution for building fire protection,making them the preferred product for modern building fire compartments.