AU657309B2

AU657309B2 - Pipe collapsing means

Info

Publication number: AU657309B2
Application number: AU12903/92A
Authority: AU
Inventors: Paul Robertson
Original assignee: Chubb Security Australia Pty Ltd
Current assignee: Chubb Security Australia Pty Ltd
Priority date: 1991-03-06
Filing date: 1992-03-13
Publication date: 1995-03-09
Anticipated expiration: 2012-03-13
Also published as: AU1290392A

Description

657309 P/:00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

TO BE COMPLETED BY APPLICANT Name of Applicant: PAUL ROBERTSON Actual Inventor(s): PAUL ROBERTSON o. Address for Service: JOHN R. G. GARDNER, PO BOX 443, MUDGEERABA QLD 4213 5 Invention titlr PIPE COLLAPSING MEANS 0 0 S Details of Associated Provisional Applications: Nos: PK 4942

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The following statement is a full description of this invention, including the best method of performing it know to me:- THIS INVENTION relates to collapsing means which is particularly applicable to collapsing the walls of a pipe or other hollow service line when the pipe or service line is subject to heat.

In many building constructions, in particular highrise building constructions, service lines or pipes are passed through walls or floors of buildings which may be constructed of slab concrete, bricks or any other material. Fire stop collars are often employed in the opening in the wall or floor of a building th-ough which the service line passes so as to provide a barrier to prevent passage of flames, hot gasses and smoke passing through the ducting or service line from one floor to the other or through walls of buildings. For this purpose the fire stop collars include an intumescent material S 15 which expands when subject to heat so as to radially compress the walls of the service line which is softened when sub.iect S: to heat. The known stop collars often also include a prestretched tension spring which acts to produce radial collapse rapidly when the service line or pipe softens.

Subsequently increase in heat causes the intumescent material to expand and provide a permanent blockage of the penetration.

The tension springs currently employed are simply of the form of a coiled spring secured together at each end to surround the service line. As the tension in the spring is released, 25 however, upon collapse of the service line or pipe the spring cannot fully close up around the pipe because the respective S coils come in contact with each other, Thus initial sealing of the pipe is not immediately achieved so that heat and gasses still passes through the ducting for a period of time.

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The present invention alms to overcome or alleviate the above disadvantages by providing an improved collapsing means for pipes or other hollow members which will serve to efficiently close off pipes or service lines in the event ot fire. The collapsing means of the present invention may be employed in any situation where pipe closure is required, such as in fire stop collars or cther similar applications. Other objects and advantages of the invention will become apparent from the following description.

The present invention thus provides collapsing means for collapsing a pipe or other hollow member formed of heat softenable material, said collapsing means having first and second resilient arms adapted for location about opposite sides of said member so as to conform substantially to the periphery of said member, means joining said arras and adapted to be located on opposite diametrical sides of said member, said arms, when said member is softened under the influence of heat, urging opposite sides of said member towards each other whereby said member adopts a collapsed substantially flattened attitude with the inside surfaces of said hollow member being juxtaposed to prevent or reduce the passage of smoke, gas or heat through said member.

The arms may comprise portions of an endless resilient element and the joining means comprise loops in the element. Suitably at least one of said loops is 2maintained in a looped attitude by fastener means.

20 Preferably, both loops are maintained in a looped attitude by fastener means. Such fastener means may comprises a rivet or rivets.

The arms may also comprise separate members and the joining means for the arms in this configuration may 25 comprise means interconnecting corresponding opposite ends 0 a of the arms. Most preferably the arms comprise coil springs.

The present invention also provides a fire stop collar assembly comprising a hollow housing adapted to surround a pipe formed of heat softenable material and collapsing means according to any one of the preceding claims disposed within said housing such that said arms surround said pipe in use, said arms being adapted to collapse said pipe when the latter softens when subject to heat.

A refractory fabric may surround the pipe and the arms are suitably arranged about the refractory fabric. A I former may be provided within the housing, the former

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Z 0 suitably comprising heat softenable material and the arms are located about the former. Most preferably, the former supports an intumescent material within the housing.

Reference will now be made to the accompanying drawings which illustrate a preferred embodiment of the invention and wherein:- Fig. 1 illustrates in sectional view a service line provided with a conventional tension spring as in the prior art; Figs. 2 and 3 illustrate one form of pipe collapsing means according to the present invention; Fig. 4 is a sectional view illustrating a pipe provided 0* F. F

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K) .4 with pipe collapsing means according to the invention; Fig. 5 is a sectional view illustrating the manner in which the pipe collapsing means of the invention serves to close off a service line or pipe; Fig. 6 is an alternative embodiment of the invention; and Figs. 7 and 8 illustrate applications of the pipe collapsing means of the invention.

Referring to Fig. 1 there is illustrated the conventional arrangement for collapsing a pipe 10 which is subject to heat, the arrangement including a prestretched tension spring 11 which is located about the pipe 10 and which may be incorporated into a fire stop collar. The spring 11 comprises a coiled spring which is held open unde- tension and S* *e S *15 which is joined at 12 at its opposite ends. When the pipe •a is subject to heat the tension spring 12 applying a radial force to the pipe 10 will cause the pipe 10 to radially compress. The coils of the spring 11 which are normally spaced apart when the spring is under tension wi Ill only permit the 20 spring 11 to close to a certain circumferential dimension indicated at 13 in Fig. 1 as the coils of the spring close up against each other. Full closure of the pipe 10 is therefore not always achieved so that heat and gasses may still pass therethrough.

25 The present invention provides an alternative collapsing means 14 which in one embodiment shown in Figs. 2 and 3 is in the form of a coil spring joined at each end, for example at 15 to provide a continuous loop which is itself is looped at two spaced positions 16 to form two arms 17 which may 30 in use be located about opposite sides of the service line or pipe. In an at rest position the respective arms 17 are urged by the resilience of the spring to the position of Fig. 3 where they are juxtaposed.

In use the pipe collapsing means 14 as shown in Fig.

4 is located about a service line or pipe 18 in the form: of Fig. 2 and being pretensioned. The opposite looped portions 16 may be fixed to any suitable holding means or alternatively a fastener 19 such as a rivet may be provided at each looped end 16 to hold the looped ends 16 in the configuration shown.

In the event that the pipe 18 is subject to heat the pretensioned arms 17 of the pipe collapsing means 14 will be urged towards each other as shown in Fig. 5 so as to cause collapse of the walls of pipe 18 and full closure of the pipe walls 20 without leaving any passage for smoke, gasses or heat.

In a further form of the invention shown in Fig. 6 the pipe collapsing means 21 may comprise a pair of spaced apart resilient elements 22 which may comprise spring elements joined at their opposite ends 23. This pipe collapsing means 21 may be used in a similar fashion to that -hown in Fig. 4 being located so that the tensioned elements 22 are located about the service line to be closed. Upon the service line being subject @0 *0 15 to heat the elements 22 will cause the sides of the service "Set*. line to collapse towards each other to close off t e line.

Referring now to Fig. 7 there is illustrated an application of the present invention to a fire stop collar assembly 24 which comprises an external housing 25 embedded in 0 20 a concrete slab 26 with a service line or pipe 27 projecting therethrough to terminate at 28 in a hollow sPace 29 within the housing 25 to permit coupling to a further line or pipe.

Located within the housing 25 is a stepped former 30 formed of S" plastics material which includes an upper portion 21 which •se 2, neatly receives the service line 25 therethrough to support same. A refractory cloth 32 is located on the outside of the former 30 and an intumescent material 33 is wrapped about the cloth 32 and around the upper portion 31 of the former 30. The r, pipe collapsing means 34 according to the present invention is 30 located beneath the material 33 and above the step 35 of the 0 former 30. The looped ends of the pipe collapsing means 34 may be secured together by rivets as before or looped over lugs within the housing When the service line 27 is subject to heat it will soften and similarly the former 30 will soften. The force exerted by the pipe collapsing means 34 will produce radial collapse of the former 30 and the service line 27 move the refractory cloth across the service line 27 so as to provide a rapid seal against a passage of heat, smoke or gasses. When exposed to further heat the intumescent material 33 will expand so as to radially close the service line 27 and provide a permanent seal.

Fig. 8 illustrates a further application of the invention to a fire stop collar 36, however, in this case a former 32 is not used but refractory cloth 37 used between the service line 38, intumescent material 39 and pipe collapsing means 40 and then is rolled up into rolls 41. This arrangement Will function in a similar manner to that described above with the pipe collapsing means 40 causing radial collapse of the service line 38 when the latter softens when subject to heat and drawing in the refractory material 37 from the rolls 41 to 15 seal the service line 38.

Whilst the pipe collapsing means of the invention is preferably in the form of a spring formed of metal it may comprise other resilient material which can be located about a service line or pipe and act in a similar manner to that 20 described above. The collapsing means of the invention may also be incorporated into any form of fire stop collar. When the pipe collapsing means is of the form shown in Figs. 1 to 5 with the ends 16 held together by rivetr or other fasteners the arms 17 may be simply pulled apart and stretched against 25 spring tension to enable it to be located about a pipe or other service line.

It will be apparent in Figs. 2 and 3 "hat the opposite looped ends 16 are formed by opposite twists of the spring of the collapsing means 14 so that in the position of Fig. 3 the portions 17 cross each other. The looped ends 16 however, may ~be twisted in the same direction so that the portions 17 are parallel to each other in the Fig. 3 position. The looped ends 16 may be held about a pipe 18 or other hollow member by means of spaced pegs on opposite sides of the member 18 which may be either located adjacent to the walls of the member 18 or spaced outwardly therefrom. Holding of the ends 16 in a fixed attitude relative to the member 18 will ensure collapsing of the member 18 in the manner shown in Fig. Whilst the above has been given by way of illustrative embodiment of the invention, all such modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as herein defined in the appended claims.

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0 25 0 *o 54 S* 5 S S 0

Claims

1. Collapsing means for collapsing a pipe or other hollow member formed of heat softenable material, said collapsing means having first and second resilient arms adapted for location about opposite sides of said member so as to conform substantially to the periphery of said member, means joining said arms and adapted to be located on opposite diametrical sides of said member, said arms, when said member is softened under the influence of heat, urging opposite sides of said member towards each other whereby said member adopts a collapsed substantially flattened attitude with the inside surfaces of said hollow member being juxtaposed to prevent or reduce the passage of smoke, gas or heat through said member.

2. Collapsing means according to Claim 1 wherein said arms comprise portions of an endless resilient element and wherein said joining means comprise loops in said '2element.

3. Collapsing means according to Claim 2 wherein at least one of said loops is maintained in a looped attitude by fastener means.

4. Collapsing means according to Claim 3 wherein said fastener means comprises a rivet.

Collapsing means according to Claim 1 wherein said arms comprise separate members and wherein said joining means comprise means interconnecting corresponding opposite ends of taid arms.

6. Collapsing means according to any one of the preceding claims wherein said arms comprise coil springs.

7. A fire stop collar assembly comprising a hollow housing adapted to surround a pipe formed of heat softenable material and collapsing means according to any one of the preceding claims disposed within said housing such that said arms surround said pipe in use, said arms being adapted to collapse said pipe when the latter softens when subject to heat.

8. A fire stop collar assembly according to Claim 7 wherein a refractory fabric surround said pipe and wherein said arms are arranged about said refractory fabric.

9. A fire stop collar assembly according to Claim 7 and including a former within said housing, said former comprising heat softenable material and wherein said arms are located about said former.

10. A fire stop collar assembly according to Claim 9 wherein said former supports an intumescent material within said housing.

11. Collapsing means substantially as hereinbefore 20 described with reference to the accompanying drawings.

12. A fire stop collar substantially as hereinbefore described with re 'erence to the accompanying drawings. DATED this twenty-first day of December 1994 PAUL ROBERTSON BY MY PATENT ATTORNEY SGARDNER JOH~ R. G. GARDNER ABSTRACT Pipe collapsing means (14) comprising an endless spring which is overlapped at two spaced positions to define loops When located about a pipe (18) portions (17) of the S* spring (15 are located on opposite sides of the pipe such that when the pipe (18) is softened when subject to heat the portions (17) are urged towards each other so that the pipe (18) is fully collapsed and closed off. c.0 o