AU628030B2

AU628030B2 - Frameworks for fire-resistant screens and doors and a channel assembly for mounting panels

Info

Publication number: AU628030B2
Application number: AU25732/88A
Authority: AU
Inventors: Peter Jackman; Jeffrey Robert Skeggs
Original assignee: BRIGGS AMASCO Ltd
Current assignee: BRIGGS AMASCO Ltd
Priority date: 1987-11-20
Filing date: 1988-11-21
Publication date: 1992-09-10
Anticipated expiration: 2008-11-21
Also published as: AU2573288A

Description

628030

AUSTRALIA

Form PATENTS ACT 1952 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE Short Title: Int. Cl: Application Number: Lodged: Complete Specification Lodged: Accepted: Lapsed: Published: Priority: Related Art: 'III I I~ I Name of Applicant: Address of Applicant: TO BE CCMPLETED BY APPLICANT BRIGGS AMASCO LTD.

Gorst Road, Park Royal, London 6LT, United Kingdom.

Actual Inventor: Address for Service: CALLINANS, Patent Attorneys, of Richmond 3121, Victoria, Australia.

48-50 Bridge Road, Complete Specification for the invention entitled "FRAMEWORKS FOR FIRE-RESISTANT SCREENS AND DOORS AND A CHANNEL ASSEMBLY FOR MOUNTING PANELS" The following statement is a full description of this invention, best method of performing it known to me:including the CHANNEL ASSEMBLY FOR MOUNTING PANELS The invention relates to an assembly for holding panels in mounting channels, especially but not exclusively, for use to mount fire-resistant glazing in doors or window frames. In such cases, although the glazing may have been designed to withstand the high temperatures likely to be encountered in fires, at these high temperatures, the glazing may still soften, causing it to sag and possibly fall out of its mounting channel, thereby destroying the integrity of the fire-resistant system.

It is known to hold a sheet of glazing in a frame, or a surround, by inserting the edge of the glazing in an open channel formed on the frame, or surround, and arranging a jI packing material, for example rubber, inside the channel to grip the edge of the glazing.

It is also known to use intumescent material as the packing in the channel in order to provide an increased grip for holding I the glazing. When subjected to a sufficiently high temperature, the intumescent material expands and exerts more gripping pressure on the edges of the glazing. This arrangement is often used in fire-resistant glazing systems.

At normal temperatures the glazing is rigid but fragile and must be supported carefully, but at temperatures above about 730'C, which are possible during a fire, the glazing can soften and an increased grip is required to hold the edges of the glazing in the mounting channels.

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With the usual arrangement, the intumescent material can, when he"panding, extrude f rom the channel, and the amount of extra grip available for holding the edge of the glazing is diminished due to the reduction in the pressure arising from the loss of intumescent material.

According to the present invention there is provided a panel mounted in a channel assembly, the channel assembly comprising a channel and intumescent material, the channel being of rigid material that is stable at high temperatures and being open on one side to receive an edge of the panel, the open side of the channel being constricted, and the intumescent material being arranged in the channel between the sides of the channel and the panel, the intumescent material, when subject to a sufficient~ly high temperature, being activated to expand and grip the edge of the panel, the constriction resisting extrusion of intumescent material from the channel.

With this arrangement, when the intumescent material is activated to expand it remains substantially within the channel, and the gripping pressure exerted on the edge of the conesro twere thenfo nt mila r syte i cnoetuefel panelricis n weaere th necn t fom ii ayte ith cnoetue el from the channel.

According to the present invention in a second aspect there is provided an assembly for-mounting a panel to be fixed relative to the assemubiy, the assembly comprising a channel of rigid material that is stable at high temperature open on one side for receiving an edge of a panel, the open side of the channel being constricted,,and intumnescent material arranged in the channel to bear diractly against the panel for gripping the edge of the panel, in use, the intumescent material, when subject to a sufficiently high temperature, being activated to 2- 1 expand to increase the gripping pressure on the edge of the panel, the constriction resisting extrusion of intumescent material from the channel.

Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:- Fig. 1 shows an example of a fire-resistant screen which may be constructed using a channel assembly in accordance with the present invention; Figure 2 shows a glazing channel fire seal for use with fire resistant glazing systems mounted in a frame member; Figure 3 shows an alternative construction of frame member; Figure 4 shows a second alternative construction of frame member; Figure 5 shows a third alternative construction of frame member; and Figure 6 shows a fourth alternative construction of frame member.

'Referring to Fig. 1, this shows a typical glazed fire-resistant screen which may be constructed using an assembly in accordance with the invention.. The screen 10 is I constructed of vertical and horizontal frame members 11 and 12 held together by spigot and socket joints 13. The screen is held in the opening 14 by means of U-shaped channels secured by screws to the edges of the opening before the screen is installed. The sides of the U-shaped channels ti i ttI trrtc

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1 overlap the frame members 11 and 12 at the periphery of the :screen to locate the screen in position. A door opening 16 is formed in the screen and two pivoted hinged doors 17 are mounted in the door opening. The doors are made up of vertical and horizontal frame members 18 and 19. The openings within the framework formed by the frame members 11 and 12 and 18 and 19 are glazed with fire-resistant glazing panels. for example of Pyran, Pyrostop, Pyrobel, Pyroswiss (Pyram, Pyrostop and Pyrobel, are registered trade marks) or of Georgian Wire Polished Plate. All the frame members are made of steel tubing to give the structure the necessary strength and integrity in the event of a fire.

The frame members comprise steel tube of rectangular cross-section. In the present example square cross-section is used. The frame member is inserted.in the channel 15 at the edge of the opening with rock wool inserted between the channel and the frame member.

Referring to Figure 2, this shows a channel assembly that may be used in the framework of Fig. 1, a sheet of fire resistant glazing 20, for example of Pyran, Pyrostop, Pyrobel, Pyroswiss or of Georgian Wire Polished Plate, has its edge 77 mounted between two strips of intumescent material 30 and 31 contained in a steel channel 50 of generally rectangular cross section.

A suitable intumescent material consists of a core of hydrated sodium silicate reinforced with glass fibres, the core being protected by a coating of expoxide resin. The channel 50 is mounted on a profiled hollow tubular steel frame 71. The channel 50 sits between, and is held in position by,, a flange 72 formed on the frame 71 and a steel bead 36 secured to the .frame 71 by a screw 73. Steel is used as it has a. high melting temperature compared with other materials, such as aluminium, which are often used to mount glazing paneltr The

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L qi channel 50 has the front edges of its side walls turned in to form lips 74 and 75 which form a constriction in the open side of the channel 50. The glazing 20 fits between the lips 74 and 75 leaving a clearance 76.

Before the intumescent material has been activated, the glazing 20 is held in position in the channel 50 by the unexpanded intumescent strips 30 and 31 packed either side of the edge 77 of the glazing 20. The clearance 76 prevents the lips 74 and 75 of the channel 50 from damaging and hence weakening the glazing 20 at the point where it enters the channel

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When the assembly is subjected to a sufficiently high i temperature, as in the case of a fire burning sufficiently close to the glazing system, the heat is conducted through the I steel mountings to the intumescent strips 30 and 31. The intumescent strips 30 and 31 expand inside the channel thereby increasing the gripping pressure exerted on the faces of the edge of the glazing 20, thus tending to hold it more firmly in the channel. The flange 72 and the bead 1= 36 buttress the side walls of the channel preventing them from distorting outwardly under the pressure of the expanding intumescent material. The turned-in lips 74 and 75 of the channel 50 resist extrusion of the expanding intumescent material from the channel 50. There may be some leakage of expanding intumescent material through the small clearance 76 at the entrance to the channel 50, but this leakage will be small. Thus, the expanding intumescent material remains 4' substantially within the channel 50, and the gripping pressure exerted on the edge 77 of the glazing 20 is greater than for a similar system with no constriction where the intumescent material can extrude freely from the channel.

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Referring to figure 3, a frame member comprise steel tube 121 of rectangular cross-section. In the present example square cross-section is used.

A first row of studs 123 is screwed into the wall 129 of the steel tube 121. The studs 123 are spaced evenly along the length of the tube. The heads 124 of the studs taper conically towards the tube so as to form an undercut 125. A first beading 126 is formed from U-shaped steel channel. The edges of the channel are turned inwardly to form inwardly projecting lips 127. The beading is pushed onto the studs channel to flex so that the lips 127 can pass over the heads 124 and grip the studs at the undercut 125. Thus the first beading is securely held in position.

The edge of a glazing panel 20 is sandwiched between two layers 30 and 31 of intumescent material.

A channel 150 of steel surrounds the edges of the glazing panel 120 and the intumescent material. The channel 150 has 1i side walls 210 and 211 which diverge away from the base 213 of the channel. The edges of the channel 150 are turned inwardly |F towards the glazing panel to form lips 176. The lips 176 are inclined at an angle of approximately 450 to the base of the channel. The lips 176 grip the sides of the glazing 120 to hold the glazing in the channel normally. The lips 176 also j| restrict the flow of intumescent material out of the channel 150 in the event of a fire. A non-combustible block 132 may be placed bwtween the edge of the glazing and the base of the channel.

The glazing and the channel are placed up against the first beading 126. A second row of studs 133, identical to the t I Ct f -6

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first, is then inserted in 'the same wall 129 on the opposite side of the glazing channel to the first row.

A second beading 134 is clipped onto the studs 133 to hold the channel in position on the frame. As can be seen in figure 3, the tapered channel wall leaves room for the mouth of the second beading, to expand to fit over the heads of the studs 133 to enable the beading to be clipped in place.

Figure 4 shows an arrangement similar to that of figure 3, but with the channel 50 having side walls which are approximately parallel to one another, and lips which are approximately parallel with the base of che channel. In this figure, the lips do not grip the glazing 20; the glazing is held by the layers of intumescent material 30 and 31.

Referring to figure 5, a first shAet steel beading 36 is formed by an inverted U-shaped chaianel which has a sideways extension 37 extending from one edge of the channel. Holes 38 are provided in the extension 37 at intervals along its length and the beading 36 is secured to the wall 29 by self-tapping screws 39 which pass through the holes 38 into holes in the wall 29. Other methods of fixing the beading to the wall 29 may be used, for example pop-riveting or spot welding.

A rib 40 is formed along the edge of the extension 37 remote from the beading 36. The rib is formed as an inverted channel of smaller dimensions that the beading 36 and tapers in width Stowards the steel tube 21 so as to form undercuts 41.

A channel 50 of steel surrounds the edges of the glazing panel Layers of intumescent material 30 and 31 are placed between the walls of the channel and the glazing panel 20 and 7

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a block of non-combustible material 32 is placed between the edge of the glazing panel and the web of the channel 50. The edges of the channel are turned inwardly towards the glazing panel to restrict the flow of intumscent material out of the channel 50, in the event of a fire.

The glazing panel 20 with the surrounding channel 50 is placed in the rebate formed between the beading 36 and the extension 37. A second sheet steel beading 51 is then pushed onto the rib 40 to hold the glazing panel 20 and channel 50 assembly in position. The beading 51 is then pushed onto Che rib 40 to hold the glazing panel 20 and channel 50 assembly in position.

The beading 51 is similar to the beading 80 of Fig. 3 except that the wall of the channel closest to the glazing panel slopes inwardly from the web portion towards the free end to allow the free end of the beading to expand sufficiently to be fitted over the rib When the beading 51 is pushed on the rib 40, the inturned lips 1.7 grip the! undercuts 41 on the rib to hold the beading in position.

Figure 6 shows an alternative arrangement for mounting the channel 50 on the frame 21. In this figure, the channel has side walls 81 and 82 that are strong enough to ensure that the shape of the channel 50 is not distorted when the intumescent strips 30 and 31 expand. Such a channel may be attached to the frame 21 without the need for any steel bead buttress supports. The channel 50 is secured to the frame 21 by screws passing through lugs (not shown) on the channel The glazing 20 can be mounted in suitable channels 50 which extend around all the edges of the glazing. However, in the event of a fire, if the glazing softens and begins to sag in rrc~~ r I a t -8- L l its frame, it is usually the top edge of the glazing which is the first to tend to fall out of its mounting channel. Thus in certain applications providing limited fire protection, it may be sufficient to mount the glazing with a channel fitting only to the top edge of the glazing.

Although the channel has been described for use to mount sheets of glazing, it will be appreciated that it could be used for mounting other types of panels.

All the frame members 11,12,18 and 19 of Fig. 1 may be constructed in the manner of Figs. 2 to 6. Where glazing panels are on both sides of the steel tube 21, beading for holding the glazing panel will be provided on two opposite walls of the steel tube.

A framework for glazed fire-resistant doors is the subject of application 81644/91 which is a division of the present application.

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Claims

1. An assembly comprising a Panel mounted in a channel assembly, the channel assembly comprising a channel and intumnescent material, the channel being of rigid material that is stable at high temperatures and being open on one side to receive an edge of the panel, the open side of the channel being constricted, and the intumescent material being arranged in the channel between the sides of the channel and the panel, the intumescent material, when subject to a sufficiently high temperature, being activated to expand and grip the edge of the panel, the constriction resisting extrusion of intumescent material from the channel.

2. An assembly according to claim 1 in which the constriction is firmly fixed in position in relation to the base of the channel.

3. An assembly according to claim 2 in which the constriction is formed by edges of side walls of the channel, which are turned in, to form a pair of opposing lips. C4. An assembly according to claim 1, 2 or 3, wherein the lips are inclined relative to the base of the channel. S. An assembly according to claima 1, 2, 3 or 4 in which the channel is of a generally rectangular shape.

6. An assembly according to any of claims I. to 5 in which the channel is carried by a f rame. An assonbly according to claim. 6 in which the channel. is mounted in a recess on the f rame. 10 i 4 ii i ICI

8. An assembly according to claim 6 in which the channel has side walls that are strong enough to withstand the increase in the pressure in the channel when the intumescent material expands, and the side walls are not supported by the frame.

9. An assembly according to claims 6, 7 or 8 in which the channel and frame are formed from steel.

10. An assembly according to claims 6, 7, 8 or 9 in which the frame forms part of a door or window.

11. An assembly according to any of claims 1 to 10 in which the channel extends around all edges of the panel.

12. An assembly according to any of claims 1 to 11 in which the panel is a glazing panel.

13. An assembly according to claim 12 in which the panel is a fire resistant glazing panel.

14. An assembly according to any claims 1 to 13, wherein a block of non-combustible material is positioned in the channel between the base of the channel and the edge of the panel. An assembly according to any of claims 1 to 14 wherein the sides of the channel diverge away from the base of the channel.

16. An assembly according to any of the preceding claims, wherein the panel is gripped by the constriction in the mouth of the channel. 11

17. An assembly according to any of claims 1 to 16, wherein the panel is gripped by the intiuescent miaterial when in the unexpended condition.

18. An assembly for mounting a panel to be fixed relative to the assembly, the assembly, comprising a channel of rigid material that is stable at high terperptures open on one side for receiving an edge of a panel, the open side of the channel being constricted, and intumescent material arranged in the channel, the intumescent material, when subject to an a sufficiently high temperature, being activated to expand to bear directly against the panel to grip the edge of the paniel, the constriction resisting extrusion of intumescent material from the channel.

19. An assenbly according to claim 18 in which the constriction is firmly fixed in position in relation to the base of the channel. An assembly according to claim 19 in which the constriction is formed by edges of side-walls of the channel, which are turned in, to form a pair of opposing lips.

21. An assembly according to claim 18, 19 or 20, wherein the lips are inclined relative to the base of the channel.

22. An assembly according to claims 18 to 2i in which the channel is of a generally rectang-ular shape.

23. An assembly according to claims 18 to 22 in~ which the intunieacent, material is arranged in two or more layers, at least one layer being positioned along each side wall of the C CO channel. 12

24. An assembly according to any of claims 18 to 23, wherein a block of non-combustible material is positioned in the chann~el adjacent the base. An asse-mbl y according to any of claims 18 to 24, wherein the sides of the channel diverge away from the base of the channel.

26. An assembly according to any of claims 18 to 25, wherein the panel is gripped by the constriction in the mouth of the channel.

27. An assembly according to any of claims 18 to 26, wherein the panel is gripped by the intumescent material when in the unexpanded condition.

28. An assembly according to any of Claims 1 to 27, wherein the channel is mounted in a framework, the framework being constructed from steel tube of rectangular cross-section, the sides of the channel being held by first and second stop beading on either side of the panel, the stop-beading being secured to the steel tube by fixing means.

29. An assembly according to claim 28, wherein tho- fixing means are concealed in the assembled condition. An assembly according to claims 28 or 29, wherein the stop beading comprises inverted channel members oi U-shaped cross section.

31. An assembly according to claim 30, wherein the fixing means comprise studs located in rows on the steel tube, the stop beading being clipped over the studs. Scj RA 41 -13- T 32, An assembly according to claim 31, wherein the channel members has its edges turned in to provide lips for gripping the studs.

33. An assembly according to claim 30, 31 or 32, wherein the studs have heads which taper towards the steel tube, such that the sides of the channel members can grip the studs.

34. An assembly according to claims 28, 29 or 30, wherein the first beading has a sideways extension which carries second fixing means for securing the second beading to the first beading. An assembly according to claim 34, wherein the first beading is attached to the tube by means of screws.

36. An assembly according to claim 34 or 35, wherein the second beading is clipped on the second fixing means. .37. An assembly according to claim 36, wherein the second fixing means comprise an inverted channel-shaped rib on the sideways extension.

38. An assembly according to claim 37, wherein the second beading comprises an inverted U-shaped channel with its'edges turned in to form lips for gripping the rib.

39. An assembly according to claim 38, wherein the rib tapers in width toward the steel tube, such that the channel can grip the rib. 14 An assembly according to any of claims 28 to 29, qpnstructed by first securing the first beading to the steel tube, locating the channel holding the edge of the glazing between the first beading and the position for the second beading, and securing the second beading in position.

41. An assembly comprising a panel mounted in en open chanel containing intumascent material substantially as described hereinbefore, with reference to figures 2 to 6 the accompanying drawings.

42. An assembly for mounting a panel, comprising an open channel containing intumescent material, substantially as described hereinbefore, with reference to figures 2 to 6 the accompanying drawings. DATED this 8th day of July 1992. BRIGGS AMASCO LTD. By their Patent Attorneys: CALLINAN LAWRIE S t p IS C C C 15 ,I cl-c~ ABSTRACT CHANNEL ASSEMBLY FOR MOUNTING PANELS (Fig. The edge of a fire resistant glazing panel (20) is received in the mouth of a channel and sandwiched between two layers of intumscent material (30, 31) located in the channel. The edges of the channel are turned inwardly towards the glazing to form lips (74, 75). The channel is mounted in the rebate of a stop beading (36) secured to a frame member The beading has a sideways extension (37) ending in a lip The lip tapers towards the frame (21) forming an undercut. A second stop beading (51) clips over the lip to butress the channel in position. The second beading has a side which is toed-in, leaving room for the beading to expand to fit over the lip In the event of a fire, to improve the integrity of the glazing structure, the intumescent material expands to grip the edge of the glazing in the channel, thereby preventing the glazing from being drawn out of the channel. The lips restrict intumescent material escaping from the channel, to improve the grip on the glazing. U 16