GB2051192A

GB2051192A - Fire Doors

Info

Publication number: GB2051192A
Application number: GB7921992A
Authority: GB
Original assignee: ROBERTS Ltd MARTIN
Current assignee: ROBERTS Ltd MARTIN
Priority date: 1979-06-25
Filing date: 1979-06-25
Publication date: 1981-01-14

Abstract

A steel fire door has in each of its two vertical edges and its top edge a rebate 20 extending along the respective edge. Within each rebate is a fire resistant seal comprising a strip 22 of intumescent material. If desired, a further seal may be provided in a rebate in the bottom edge of the door. Alternatively, some or all of the seals may be provided in rebates in the corresponding facing surfaces of the steel frame in which the door is fitted. The intumescent material may have a protective covering 23 of plastics. <IMAGE>

Description

SPECIFICATION Steel Fire Doors and Steel Frames Therefor This invention relates to steel fire doors and steel frames therefor.

According to the invention a steel fire door has in each of its two vertical edges and its top edge a rebate extending along the respective edge and containing a fire resistant seal comprising a strip of intumescent material.

The invention also provides a steel frame for a fire door, comprising a head member and two jambs, wherein each surface of the frame which, in use, faces one of the vertical edges or the top edge of the door has a longitudinal rebate containing a fire resistant seal comprising a strip of intumescent material.

The invention further provides a steel fire door, in combination with a steel frame comprising a head member and two jambs, wherein at least one of the facing surfaces of the door and the frame, at each of the vertical edges and the top edge of the door, is provided with a longitudinal rebate containing a fire resistant seal comprising a strip of intumescent material.

In the case of the steel fire door or combination described above, the bottom edge of the door may also have a rebate extending along the edge and containing a fire resistant seal comprising a strip of intumescent material.

Preferably each fire resistant strip is flush with the associated door edge or surface of the door frame.

It is also preferred that each fire resistant strip comprises a core of intumescent material and a protective sheath of plastics material.

By way of example, specific embodiments in accordance with the invention will be described with reference to the accompanying drawings in which: Figure 1 is a perspective view of a steel fire door for fitting in a steel frame shown in chain-dot lines; Figure 2 is a section along line 2-2 in Figure 1; Figure 3 is a perspective view of a steel frame for a steel fire door, the door being shown in chain-dot lines; Figure 4 is a section along line 4-4 in Figure 3; and Figure 5 is a perspective view of a steel fire door fitted to a steel frame.

Referring to Figures 1 and 2 of the drawings, a steel fire door 10 comprises an inner zinc coated steel skin 1 1 and an outer zinc coated steel skin 12. In this embodiment, two opposed edges of the outer skin 12 are bent to form the vertical edges 1 6, 1 7 of the door, which edges 1 6, 17 are joined to the adjacent edges of the inner skin 11 by lock-seam joints 13. The top and bottom edges 18, 19 of the inner and outer skins 1 1, 12 are joined by intermediate channel members inserted between the skins and welded thereto. Between the skins 1 1, 12 are vertical stiffeners 14, of Z cross-section, and the door has an in-fill 15 of mineral wool. If desired, the vertical edges 1 6, 1 7 of the door may be formed by channel members in like manner to the top and bottom edges 18, 19 to avoid forming the lock-seam joints 13.

Along each of the vertical edges 1 6, 17 and the top edge 18 of the door, and in this embodiment also the bottom edge 19, there is formed a rebate 20 which in this embodiment is located adjacent to the inner skin 11. Within the rebate 20 on each edge of the door is a fire resistant seal comprising a strip 22 of intumescent material which, in this embodiment, is flush with the door edge. The intumescent material is hydrated sodium silicate reinforced with glass fibres and is covered by a sheath 23 of epoxide resin to protect the intumescent core 24 from damage by water or atmospheric carbon dioxide which would otherwise degrade the core.

The strip 22 is held in the rebate by adhesive or, alternatively, by screws.

In the event of fire, the plastics sheath 23 melts and the intumescent core 24 foams to a volume which may be ten times its initial volume to fill the gap between the respective door edge and the facing surface of the frame 25 which, in this embodiment, is a conventional steel frame (shown in chain-dot lines) having a head member 26 and two jambs 27. The steel fire door of this embodiment is capable of passing a 2 hour fire test to British Standard No. 476 Part 8 (1972) for stability and integrity.

If desired the strip 22 of the intumescent material in the bottom edge 19 of the door may be omitted, but its provision has the advantage that, in the event of fire, the gap beneath the door is sealed. Another advantage is that the door may be turned upside down and fitted as a left-hand opening door.

Figures 3 and 4 concern another embodiment involving substantially the same door and frame except that the two vertical seals and the top seal are provided by strips 30 of the intumescent material in respective rebates 31 in the jambs 35 and the head member 36 of the frame 32 instead of the door 33. Again each rebate is conveniently aligned close to the inner skin 34 of the door when the door is closed. As in the embodiment of Figures 1 and 2, if desired, the bottom edge of the door may be provided with a further strip of the intumescent material.

A further embodiment is shown in Figure 5 in which the vertical seals are provided by strips 40 of the intumescent material in respective rebates in the jambs 45 of the frame 41 and both top and bottom seals are provided by respective strips 42, 43 of the intumescent material in rebates in the door 44. Of course, any other combination of seals in the door and the frame may be provided.

Claims

1. A steel fire door having in each of its two vertical edges and its top edge a rebate extending along the respective edge and containing a fire resistant seal comprising a strip of intumescent material.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Steel Fire Doors and Steel Frames Therefor This invention relates to steel fire doors and steel frames therefor. According to the invention a steel fire door has in each of its two vertical edges and its top edge a rebate extending along the respective edge and containing a fire resistant seal comprising a strip of intumescent material. The invention also provides a steel frame for a fire door, comprising a head member and two jambs, wherein each surface of the frame which, in use, faces one of the vertical edges or the top edge of the door has a longitudinal rebate containing a fire resistant seal comprising a strip of intumescent material. The invention further provides a steel fire door, in combination with a steel frame comprising a head member and two jambs, wherein at least one of the facing surfaces of the door and the frame, at each of the vertical edges and the top edge of the door, is provided with a longitudinal rebate containing a fire resistant seal comprising a strip of intumescent material. In the case of the steel fire door or combination described above, the bottom edge of the door may also have a rebate extending along the edge and containing a fire resistant seal comprising a strip of intumescent material. Preferably each fire resistant strip is flush with the associated door edge or surface of the door frame. It is also preferred that each fire resistant strip comprises a core of intumescent material and a protective sheath of plastics material. By way of example, specific embodiments in accordance with the invention will be described with reference to the accompanying drawings in which: Figure 1 is a perspective view of a steel fire door for fitting in a steel frame shown in chain-dot lines; Figure 2 is a section along line 2-2 in Figure 1; Figure 3 is a perspective view of a steel frame for a steel fire door, the door being shown in chain-dot lines; Figure 4 is a section along line 4-4 in Figure 3; and Figure 5 is a perspective view of a steel fire door fitted to a steel frame. Referring to Figures 1 and 2 of the drawings, a steel fire door 10 comprises an inner zinc coated steel skin 1 1 and an outer zinc coated steel skin 12. In this embodiment, two opposed edges of the outer skin 12 are bent to form the vertical edges 1 6, 1 7 of the door, which edges 1 6, 17 are joined to the adjacent edges of the inner skin 11 by lock-seam joints 13. The top and bottom edges 18, 19 of the inner and outer skins 1 1, 12 are joined by intermediate channel members inserted between the skins and welded thereto. Between the skins 1 1, 12 are vertical stiffeners 14, of Z cross-section, and the door has an in-fill 15 of mineral wool. If desired, the vertical edges 1 6, 1 7 of the door may be formed by channel members in like manner to the top and bottom edges 18, 19 to avoid forming the lock-seam joints 13. Along each of the vertical edges 1 6, 17 and the top edge 18 of the door, and in this embodiment also the bottom edge 19, there is formed a rebate 20 which in this embodiment is located adjacent to the inner skin 11. Within the rebate 20 on each edge of the door is a fire resistant seal comprising a strip 22 of intumescent material which, in this embodiment, is flush with the door edge. The intumescent material is hydrated sodium silicate reinforced with glass fibres and is covered by a sheath 23 of epoxide resin to protect the intumescent core 24 from damage by water or atmospheric carbon dioxide which would otherwise degrade the core. The strip 22 is held in the rebate by adhesive or, alternatively, by screws. In the event of fire, the plastics sheath 23 melts and the intumescent core 24 foams to a volume which may be ten times its initial volume to fill the gap between the respective door edge and the facing surface of the frame 25 which, in this embodiment, is a conventional steel frame (shown in chain-dot lines) having a head member 26 and two jambs 27. The steel fire door of this embodiment is capable of passing a 2 hour fire test to British Standard No. 476 Part 8 (1972) for stability and integrity. If desired the strip 22 of the intumescent material in the bottom edge 19 of the door may be omitted, but its provision has the advantage that, in the event of fire, the gap beneath the door is sealed. Another advantage is that the door may be turned upside down and fitted as a left-hand opening door. Figures 3 and 4 concern another embodiment involving substantially the same door and frame except that the two vertical seals and the top seal are provided by strips 30 of the intumescent material in respective rebates 31 in the jambs 35 and the head member 36 of the frame 32 instead of the door 33. Again each rebate is conveniently aligned close to the inner skin 34 of the door when the door is closed. As in the embodiment of Figures 1 and 2, if desired, the bottom edge of the door may be provided with a further strip of the intumescent material. A further embodiment is shown in Figure 5 in which the vertical seals are provided by strips 40 of the intumescent material in respective rebates in the jambs 45 of the frame 41 and both top and bottom seals are provided by respective strips 42, 43 of the intumescent material in rebates in the door 44. Of course, any other combination of seals in the door and the frame may be provided. Claims

2. A steel frame for a fire door, comprising a head member and two jambs, wherein each surface of the frame which, in use, faces one of the vertical edges or the top edge of the door has a longitudinal rebate containing a fire resistant seal comprising a strip of intumescent material.

3. A steel fire door in combination with a steel frame comprising a head member and two jambs, wherein at least one of the facing surfaces of the door and the frame, at each of the vertical edges and the top edge of the door, is provided with a longitudinal rebate containing a fire resistant seal comprising a strip of intumescent material.

4. A door or combination as claimed in Claim 1 or Claim 3, wherein the bottom edge of the door also has a rebate extending along the edge and containing a fire resistant seal comprising a strip of intumescent material.

5. A door or frame or combination as claimed in any one of the preceding claims, wherein each fire resistant strip is flush with the associated door edge or surface of the door frame.

6. A door or frame or combination as claimed in any one of the preceding claims, wherein each fire resistant strip comprises a core of intumescent material and a protective sheath of plastics material.

7. A steel fire door substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

8. A steel frame for a fire door substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

9. A steel fire door in combination with a steel frame substantially as hereinbefore described with reference to and as shown in the accompanying drawings.