GB2419385A

GB2419385A - Insulated pipe coupling for use in fire retarding barriers

Info

Publication number: GB2419385A
Application number: GB0423505A
Authority: GB
Inventors: Ian Smith; Christopher Newman
Original assignee: Saint Gobain Pipelines PLC
Current assignee: Saint Gobain PAM UK Ltd
Priority date: 2004-10-22
Filing date: 2004-10-22
Publication date: 2006-04-26
Anticipated expiration: 2024-10-22
Also published as: GB2419385B; GB0423505D0

Abstract

A flanged pipe coupling 10 has insulating material 13 disposed between the flanges 18, 21 to limit heat conduction between the two pipe ends 17, 19. The joint is disposed within a fire retarding partition or barrier 16, so that when one side of the partition 16 is exposed to fire, the insulation 13 in the joint 10 reduces the heat transfer to the other side, thus reducing the temperature rise of the pipe on the other side of the barrier. One of the flanges 18 may be located at the end of a pipe 11, and the other flange 21 may be spaced from the end of the other pipe 12. There may be a separate sealing member 14, and the insulation 13 may comprise high purity ceramic fibres. The two flanges 18, 21 may be connected by bolts (29, figure 4, 5), and there may be an insulating washer (32, figure 4, 5) between the flange and the nut.

Description

IMPROVEMENTS IN OR RELATING TO

PIPEWORK ASSEMBLIES

This invention relates to pipework assemblies. In particular, but not exclusively, the invention concerns drainage or waste pipes in buildings.

Typically such pipes are made from cast iron or plastics, although other materials are also possible. The invention is primarily concerned with metallic pipes such as but not limited to cast iron pipes.

Lengths of drainage pipe are fastenable one to another to form a pipework assembly extending through a building.

In order to prevent the spread of fire in a building it is often necessary to include thermally insulating and/or fire retarding barriers. Typically these barriers are incorporated into, or adjacent to, the walls or floors that separate respective areas of the building. Building regulations in the UK refer in this regard to "fire walls between compartments". The invention is applicable to such fire walls, and is also applicable in other kinds of barrier providing a to thermally insulating and/or fire retarding effect.

The worker of the skill in the art will be familiar with the phrase "fire walls between compartments" but for convenience herein the phrase "thermally insulating and/or fire retarding barriers" is preferred, not least because the :5 latter signifies that the barriers need not be the walls of a compartment per se. Normally such barriers are or include concrete or other non flammable materials.

The routing of pipework through a building often results in the pipework passing through a thermally insulating or fire retarding harrier, that may be embodied as a wall or a floor.

Building regulations specify insulation values for pipeworl; assemblies passing through such thennally or fire retarding insulating barriers.

Typically in the regulations the insulation values are expressed as the time taken, in minutes, for the pipework on one side of a barrier to increase in lo temperature by a predetermined amount, when the other side of the barrier is heated to a particular temperature simulating the existence of a fire.

Obviously a high insulation value is desirable. Building regulations specify an insulation value between 30 minutes and 120 minutes depending on the building type, the number of storeys, and whether the building includes a sprinkler system.

One way of increasing the insulation value of a pipework assembly is to wrap the pipework protruding from each side of the barrier in an insulating material such a Rockwool (RTM) or plaster of Paris. The insulating wrap impedes the transfer of heat into the pipework. As a result the rate of heat transfer by the pipework assembly through the thermally insulating or fire retarding barrier is also reduced, thereby improving the insulation value of the assembly.

However, wrapping the pipework assembly is tine-consuming and costly. It is also awkward, particularly in closely confined installations.

Therefore there is a need for a pipework assembly that provides an increased insulation value without the need to wrap at least a part of the pipeworlk assembly in an insulating material.

According to the invention there is provided a pipeworl: assembly comprising: first and second pipes having respective first and second ends, each said end including protruding therefrom a protuberance, the said ends defining a joint between the pipes; and the said protuberances being directly lo or indirectly interconnected to secure the joint, wherein: (a) the protuberances are spaced from one another in the resulting pipework assembly; (b) an insulating material lies in the space bet-weep the protuberances to limit heat conduction therebetween; and (c) the insulating material lies within a thermally insulating and/or fire retarding barrier such that each said pipe extends towards a respective side of the barrier.

Limiting heat conduction between the first and second protuberances reduces the overall rate of heat transfer from one pipe to the other, thereby increasing the insulation value of the pipework assembly.

The insulating material provides this benefit without the need to wrap either of the first or second pipes in a thermally insulating material.

Locating the insulation material within a barrier as aforesaid has the advantage of protecting the insulating material from the effects of a fire on either side of the barrier. This extends the usable lifetime of the insulating material.

In a preferred embodiment of the invention the protuberance of the first pipe is adjacent to the first end, and the protuberance of the second pipe is spaced from the second end. This provides a way of accommodating the insulating material while creating a fluid-tight seal between the pipes.

Preferably both the protuberances lie within the thermally insulating and/or fire retarding barrier. As a result each protuberance forms a heat sink in the barrier' thereby increasing the rate at which each pipe is able to dissipate heat into the barrier. This reduces the rate at which heat is conducted o between the pipes. This further improves the insulation value of the pipework assembly.

Optionally one protuberance lies within the thermally insulating and/or fire retarding barrier. This arrangement allows the one protuberance to form a hi heat sink in the barrier, while permitting easy access to the insulating material for repair or replacement, e.g. following a fire.

Conveniently each protuberance defines an annular flange. As a result the pipework assembly is easy to assemble. In one embodiment of the so invention the pipework assembly is pre-assembled prior to installation in the thermally insulating and/or fire retarding barrier. As a result a user is able easily to connect other pipes or apparatuses to either pipe that preferably protrudes on a respective side of the barrier.

For the avoidance of doubt, however, as described hereinbelow it is not mandatory that each, or indeed either, pipe protrudes from the barrier.

According to a preferred embodiment of the invention at least one annular flange includes at least one protrusion extending therefrom. The or each protrusion helps to locate a respective pipe within the thermally insulating and/or fire retarding barrier.

In a preferred embodiment of the invention the first end defines a recess that receives a sealing member. This feature provides a convenient way of creating a fluid-tight seal that is readily manufacturable.

Optionally the thermal conductivity of the insulating material is not more than 0.192 W my K- at a median temperature of 1000 C.

Preferably the insulating material has a thickness of between 4.5mm and 20mm. Optionally the invention may limit the degree to which the insulation material is compressed by using ea. a specific length of bolt to interconnect the pipes. ]5

In one embodiment of the invention the insulating material is or includes high-purity ceramic fibres.

The foregoing features of the insulating material provide a desired so insulation value in an economical and readily achievable manner, although other types and amounts of material are also possible within the scope of the invention.

According to a preferred embodiment of the invention each of the first pipe and the second pipe have an external diameter of between about 60mm and about 325mm, and more specifically between 57mm and 329mn1.

Optionally the protuberances are interconnected by at least one nut and bolt.

This provides a ready way of fastening one pipe to another.

A further, preferred embodiment of the invention includes an insulating washer lying between a said protuberance and at least one of the nut, or the head of the bolt.

Each insulating washer provides an additional barrier to thermal conduction between the first and second pipes, thereby improving the insulation value of the assembly.

In one optional embodiment of the invention at least one bolt includes a lo bracket lying adjacent at least one of the nut, the insulating washer or the head of the bolt. The or each bracket helps to locate the pipework assembly in the thermally insulating barrier. However in embodiments of the invention intended to be brought into an aperture in a barrier from below this feature is not regarded as necessary.

Preferably the pipework assembly has an insulation value up to 120 minutes. Such an insulation value is sufficient to meet the current building regulations.

so There now follows a description of preferred embodiments of the invention, by way of non-limiting example, with reference being made to the accompanying drawings in which: Figure] shows a cross-sectional, plan view of a pipework assembly according to a first embodiment of the invention; :5 Figure 2A shows a plan view of a first pipe shown in Figure 1; Figure 2B shows an elevational view from one end of the pipe shown in Figure 2A; Figure 3A shows a plan view of a second pipe shown in Figure 1, Figure 3B shows an elevation view from one end of the pipe shown so in Figure 3A; Figure 3C shows a cross-sectional view along line A-A of the pipe shown in Figure 3A; Figure 4 shows a perspective view of a pipeworl; assembly according to a second embodiment of the invention; s Figure 5 shows a cross-sectional view of a pipework assembly according to a third embodiment of the invention, Figure 6 shows in perspective view a pipework assembly according to a fourth embodiment of the invention by way of illustration of several features that may be employed on their own, in combination with one lo another or in combination with features of the other embodiments of the invention described herein.

A first embodiment of pipeworl; assembly is designated generally by the reference numeral l 0.

The assembly comprises a first pipe 11; a second pipe 19; an insulating material 13; and a sealing member 14. In the embodiment shown each pipe 11, 12 protrudes on a respective side of a thermally insulating and/or fire retarding barrier 16, which may be e.g. a compartment wall (or another kind so of wall); or a floor. In other embodiments only one, or (in some cases) neither of the pipes 1], ] 2, protrudes from the barrier 16.

The first pipe I I includes a first end indicated generally by numeral 17, and adjacent thereto on the exterior of the pipe a first protuberance in the form :s of a first annular flange 18 (as shown in Figure 2B). The second pipe includes a second end indicated generally by numeral l 9, and spaced therefrom a second protuberance in the form of a second annular flange 21 (as shown in Figure 3B). Other embodiments of the invention may incorporate different shapes or combinations of protuberances.

The first Range 18 includes four equally spaced webs 22 attached between it and an outer surface of the first pipe 11. The second flange 21 includes three equally spaced webs 23 attached between it and an outer surface of the second pipe 12. The webs 22, 23 strengthen the respective flanges 18, 21. In other embodiments of the invention the numbers and spacings of the webs 22, 23 may differ from those shown.

The ends 17, 19 of the pipes define a joint 24 between the two pipes 1 1, 12.

The flanges 18, 21 are fastened together to secure the joint 24. lo

The flanges 18, 21 are spaced from one another. The insulating material 13 lies in the space between the flanges 18, 21. The insulating material 13 is in the form of an annular ring. The ring has an outside diameter that in the embodiment shown is substantially equal to an outside diameter of the second flange 21; and an inside diameter that is substantially equal to an outside diameter of the second pipe 12.

In other embodiments of the invention (such as the fourth embodiment described hereinbelow) the outer diameter of the annulus 13 of insulating SO material may be sufficiently large as to protrude transversely beyond the edge of one or both the flanges 18, 21 about at least part of (and preferably all of) its periphery.

The insulating material 13 limits the conduction of heat from one flange 18, :5 21 to another, thereby limiting the conduction of heat from one pipe 11,12 to another. This improves the insulation value of the pipework assembly 10.

The insulating material 13 lies within the thermally insulating barrier 16.

Having the insulating material 13 lying in the thermally insulating barrier so 16 helps to protect it in the event of a fire.

The flanges 18 21 also lie within the thermally insulating barrier 16. As a result they are able to act as heat sinks to increase the rate at which each pipe 11, 12 dissipates heat into the barrier l6. This further reduces the rate of heat conduction between the two pipes 11' 12, thereby increasing the insulation value of the pipeworlL assembly 10.

The first end 17 defines an annular recess 96 that receives the sealing member 14. This provides a sealing contact between the first and second lo ends l 7, 19. In this embodiment of the invention the recess has a depth of 5.0mm. In addition the sealing member 14 is a rubber sealing gasket. Other depths of recess; and types or shapes of seal are also possible.

The maximum thermal conductivity of the insulating material 13 is 0.192 Wm' K-' at a median temperature of 1000 C. The thermal conductivity of the material 13 varies depending upon the median temperature. Typically at a median temperature of 600 C the thermal conductivity is 0. 080 Wm- K-'; and a 800 C the thermal conductivity is 0.110Wm-iK.

The insulating material 13 has a thickness of 4.5mm. In other embodiments the thickness of the insulating material 13 can vary from 4.5mm to 20mm, depending on the thermal conductivity of the material 13 and the size of the first and second pipes 11, 12.

The insulating material 13 is high-purity ceramic timbres. Other types of insulating material are also possible.

The first and second pipes 11, 12 have an outside diameter of 110mm. In another embodiment the diameter of the first and second pipes 11, 12 can range from 60mm to 325mm.

The outside diameter of each flange is 170mm. The thickness of the first flange 18 is 4.5mm. The second flange 21 has a thickness of 6.0mm. The second flange 21 is spaced from the second end by 10.5mm. In further embodiments the foregoing dimensions may vary.

lo Each flange 18, 21 and the insulating material 13 includes three, mutually aligned, through-going holes 27, 28 (not shown in the insulating material 13). Each through-going hole 27, 28 receives a threaded bolt 29 which in combination with a nut 31 fastens the first and second flanges 18, 21 together to secure the joint 24. Other numbers of through-going holes and nut and bolt combinations are also possible. Furthermore, in other embodiments of the invention the pipes 11, 12 can be interconnected in other ways, such as casting the flanges 18, 21 in concrete or using external clamps.

In other embodiments of the invention each bolt 29 includes an insulating washer 32 lying between at least one of its head, or the nut 31, and a respective flange 18, 21. This provides an additional degree of thermal insulation between the first and second pipes 11, 12.

The insulation value of the pipework assembly is up to 120 minutes.

Figure 4 shows a pipework assembly 20 according to a second embodiment of the invention. The features of this embodiment that are the same as those in the first embodiment share the same reference numerals and are not described in detail.

The second flange 21 includes three flange protrusions 33 spaced at equal intervals about the periphery. The flange protrusions 33 help to locate the second pipe]2 within the thermally insulating barrier 16. As shown in Figure 4 each protrusion 33 is a laminar extension of the flange 21. Each protrusion is shaped as a truncated triangle having curved edges. Other numbers, shapes and sizes of flange protrusions 33 are also possible. The protrusions 33 need not be identical to one another. Also, in further arrangements the first flange l 8 may include one or more flange lo protrusions.

A third embodiment of pipework assembly 30 according to the invention is shown in Figure 5. The features of this embodiment that are the same as those in the two previous embodiments share the same reference numerals and are not described in detail.

In the third embodiment of the pipework assembly 30 each bolt 29 includes a bracket 34 lying between the nut 31 and the insulating washer 32. In other arrangements the bracket 34 may be located elsewhere along the length of so the bolt 29. The bracket 34 helps to locate the pipework assembly 30 in the thennally insulating barrier 16.

During installation the annular flange 18, 21 is often used to assist in positioning a respective pipe 1 l, 12 a desired distance from a wall, floor or :5 ceiling. This is done by positioning an edge of the flange l 8, 2 l against the wall, floor or ceiling, thereby ensuring that the remainder of the pipe l 1, 12 is, e.g. 30mm from the wall, floor or ceiling.

Figure 6 shows a fourth embodiment of the pipework assembly lo of the so invention. The following description refers only to the differences between the Figure 6 arrangement and the other embodiments of the invention described herein.

The Figure 6 assembly l 0 omits the webs 22 of the Figure l embodiment.

s This allows the assembly] O of the Figure 6 to be introduced into a preformed aperture in a floor or wall, the size of which needs only to be slightly greater than the diameter of pipe 12.

The webs 23 of the Figure 1 arrangement may be similarly omitted if lo desired, but such omission is not apparent in Figure 6 since the annulus 13 of insulating material is, over the majority of its extent, of greater diameter than the diameter of the flanges of which one, 21, is visible.

Flange 21 shows extending transversely of its periphery a series of three Is laminar protuberances 33' that are similar to the truncated, essentially triangular protrusions 33 of Figure 4. In the Figure 6 embodiment the free tips of the protuberances 33' terminate at the periphery of the annulus 13.

Figure 6 also shows second pipe 12 as being of sufficiently short length so JO as not to protrude beyond the barrier 16 in which the assembly lO is installed. Pipe 11 may also optionally be of a similar length. Aside from giving rise to material savings, the use of one or more short spigots as the pipes 11, 12 provides the ability to connect the assembly lO to a range of other assemblies or components including but not limited to manifolds and as other pipes. Such connection could if desired occur within a thermally insulating or fire resistant barrier 16.

The above-described features of the Figure 6 embodiment need not be present in combination with one another. Moreover, any one or more of so them may optionally be present in the other embodiments of the invention described herein. Moreover the features of the various embodiments of Figures l to 5 may also be combined in various ways that will be apparent to the worker of skill in the relevant art. All such combinations lie within the scope ofthe invention as claimed.

Claims

CLAIMS: 1. A pipework assembly comprising: first and second pipes having

respective first and second ends, each said end including protruding therefrom a protuberance, the said ends defining a joint between the pipes; and the said protuberances being directly or indirectly interconnected to secure the joint, wherein: (a) the protuberances are spaced from one another in the resulting pipework assembly; lo (b) an insulating material lies in the space between the protuberances to limit heat conduction therebetween; and (c) the insulating material lies within a thermally insulating and/or fire retarding barrier such that each said pipe extends towards a respective side of the barrier.
2. A pipework assembly according to Claim 1 wherein the protuberance of the first pipe is adjacent to the first end, and the protuberance of the second pipe is spaced from the second end.

so
3. A pipework assembly according to Claim 1 or Claim 2 wherein both of the protuberances lie within the thermally insulating and/or fire retarding barrier.
4. A pipework assembly according to Claim I or Claim 2 wherein one o5 protuberance lies within the thermally insulating barrier.
5. A pipework assembly according to any preceding claim wherein each protuberance defines an annular flange.
6. A pipework assembly according to Claim 5 wherein at least one annular flange includes at least one protrusion extending therefrom.
7. A pipework assembly according to any preceding claim wherein the first end defines a recess that receives a sealing member.
S. A pipework assembly according to any preceding claim wherein the thermal conductivity of the insulating material is not more than 0.192 W m- K-, at a median temperature of 1000 C.
9. A pipework assembly according to any preceding claim wherein the insulating material has a thickness of between 4.5mm and 20mm.
10. A pipework assembly according to any preceding claim wherein the insulating material is or includes high-purity ceramic fibres.
11. A pipework assembly according to any preceding claim wherein each of the first pipe and the second pipe have an external diameter of between about 60mm and about 325mm.
12. A pipework assembly according to any preceding claim wherein the protuberances are interconnected by at least one nut and bolt.
]3. A pipework assembly according to Claim 12 including an insulating o5 washer lying between at least one of a head of the bolt or the nut and a respective protuberance.
14. A pipework assembly according to Claim 12 or 13 wherein at least one bolt includes a bracket dying adjacent at least one of the nut, the so insulating washer or the head of the bolt.
15. A pipework assembly according to any preceding claim having an insulation value up to 120 minutes.
16. A pipework assembly generally as herein described with reference to and/or illustrated in the accompanying drawings.