AU2016102421A4 - Sprinkler outlet formwork for concrete encasement applications and prefabricated assemblies and methods of construction incorporating the same - Google Patents

Abstract

Abstract A modular formwork system for encasing fire control pipe work or the like within a concrete slab. The formwork includes a specially configured outlet housing device, and a connected pipe conduit. In preferred forms the outlet housing enables prefabrication of a combined pipe work and form work assembly which is easily installed by connection to the slab formwork prior to pouring the slab. Preferably the housing is configured to enable the internal pipe work to be located in a first position fully within the form work for installation, and a second position with the free end of the pipe accessible for connection to supply pipes.

Description

Sprinkler outlet formwork for concrete encasement applications and prefabricated assemblies and methods of construction incorporating the same

Field of the invention [0001 ] The present invention relates to a formwork system to form a sleeve in cast concrete to allow for the installation, repair and replacement of special purpose pipe work such as sprinkler pipe work, and to a pipe and formwork prefabricated sub assembly utilising the same.

[0002] The invention has been developed primarily for use in installing sprinkler system pipe work in the balcony regions of multi storey concrete floor residential buildings, and will be described with reference to this application. However, it will be appreciated that the invention may be suitable for use in other areas of construction where it is desirable to concrete encase pipe work of a similar kind that needs to be capable of post installation movement for maintenance, replacement and repair.

Background to the invention [0003] Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.

[0004] Fire control systems including sprinkler systems have long been standard inclusions for all areas of residential building in Australia exceeding 25 meters in effective height. However, the industry has been avoiding sprinklers on balconies through fire engineering practices, as they were difficult to install, costly and not very architecturally pleasing. The rationale was that a large fire on a balcony was not likely. Unfortunately however, over the last few years there have been some fires on balconies that have caused severe damage and even death. This has led to the industry requiring that balcony sprinklers should be utilised in these areas as required under the Australian standard. Importantly, sprinkler system pipe work has to be installed in a manner whereby it can be removed and repaired or replaced if required [0005] To date sprinkler systems have been installed in balconies in several different ways. In some instances, the sprinkler system pipe work extends from within the internal ceiling out above the wall or door or window opening header, and is connected to the underside of the balcony roof. This roof structure is in most cases the underside of the concrete slab forming the floor of the unit or level of units on the storey above. While relatively straight forward, this

2016102421 31 Mar 2016

- 2 method of installation then requires a false ceiling to then be installed to cover up the unsightly pipe work. This adds considerable cost and labour time and reduces the headspace that would otherwise be available in the balcony region.

[0006] To avoid this encroachment into the available headspace, other solutions have included chasing channels into the underside of the roof slab so that the pipes are located within the body of the slab. However, this is a very costly process, as the channels have to be manually excavated to a depth sufficient to locate the pipe and the main body portion of a conventional fixed sprinkler head, or the complete assembly of a fully recessed ‘drop down’ sprinkler assembly, both of which are to be concealed within the ceiling structure within some form of protective sheathing. This secondary excavation process can damage the slab structure and undermine the reinforcement. Further, the excavated channels then need to be filled and finished after the pipes have been installed which again is extremely costly and time consuming.

[0007] Yet another method manages to obviate the need to excavate into the slab after it has cured, by instead forming channels during the casting of the slab This is often done using currently available building materials such as square section guttering or the like to form the channel. This can reduce the amount of installation labour and finishing work required, depending on whether the channel is open or fully encased. However, there is still the issue of needing to manually finish at least a portion of the outer ceiling surface, including the difficult region around what needs to be an accurate circular opening for the sprinkler head and associated fittings. Furthermore, this method is unlikely to comply with related building codes, and/or meet the stringent engineering requirements for a concrete floor/ceiling slab, unless there is prior modification to the slab design. This is because the large voids formed by the channels can compromise the overall structural integrity of the slab, and/or lead to inadequate concrete cover on the internal steel reinforcement in the floor/ceiling slab.

[0008] It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

-32016102421 31 Mar 2016

Summary of the invention [0009] According to a first aspect of the invention, there is provided an outlet housing for concrete encasement of a pipe end with elbow fitting for a sprinkler body, the housing including:

a chamber sized to receive a pipe end with elbow fitting and a sprinkler body;

a first outlet from the chamber configured to provide an opening sized to neatly accommodate a sprinkler body, the first outlet having a first axis; and a second outlet from the chamber adapted to receive and retain a conduit through which the pipe with the pipe end can extend, the second outlet having a second axis.

[0010] In use, the outlet housing will, in most embodiments, be oriented with the first outlet at the base of the housing so as to provide an opening in the underside of a ceiling slab with the first axis generally vertical, and the second outlet and second axis will extend generally horizontally so as to be generally transverse to the first opening and first axis.

[0011] Preferably, the chamber is sized to facilitate a predetermined amount of translational movement of the pipe and elbow assembly along the second axis to one or both sides of the first axis. This facility may be provided by generally increasing the size of a portion of the chamber intermediate the two outlets, or more preferably by defining a primary chamber that extends about the first axis that will accommodate the elbow and sprinkler body, with one or two smaller secondary chambers or regions that extend about the second axis that need be sized only to accommodate the pipe and elbow, thereby minimising the overall volume of the housing.

[0012] In one preferred form the first outlet is generally cylindrical and extends from a central portion of the chamber. Preferably the inner diameter of the cylindrical outlet is sized to neatly accommodate a sprinkler body of a conventional fixed head sprinkler, or sprinkler body with drop down sprinkler head assembly of the kind that are flush mounted at installation and only drop down into the space below once activated.

[0013] In a preferred form the outer diameter of the cylindrical outlet is sized to seat closely within a standard form board mountable deck box sleeve of the kind commonly used in concrete construction for casting apertures for down lights and the like.

-42016102421 31 Mar 2016 [0014] Preferably, the second outlet is in the form of a hollow spigot adapted to receive a suitably sized conduit for the pipe. In one form the spigot is sized to receive the pipe internally, and includes a shoulder to limit and locate an end of the pipe receiving conduit.

[0015] The outlet housing may be manufactured in one piece or assembled from two or more components to facilitate easier manufacture.

[0016] According to a second aspect of the invention, there is provided a modular lost formwork system for concrete encasement of fire control pipe work, the system including: an outlet housing for concrete encasement of a pipe end with elbow fitting for a sprinkler body according to the first aspect of the invention; and a length of pipe receiving conduit connected to the second outlet.

[0017] Optionally, the system further includes an adapter to enable connection to the distal end of the pipe remote the outlet housing, the adapter having a body including;

a conduit receiving inlet;

a pipe outlet; and means to secure the adapter to formwork as required.

[0018] Preferably the body of the adaptor includes a region sized to provide adequate clearance around the pipe to provide easy access to an end of the pipe for moving the pipe if and when required.

[0019] Desirably the inlet is in the form of a spigot of similar form to that provided in the outlet housing, optionally configured to sit over the pipe receiving conduit, ideally again with an internal shoulder to limit travel of the conduit into the adaptor.

[0020] In a preferred form the means to secure the adapter to formwork comprises one or more flanges with apertures for receiving appropriate fasteners such as nails, screws/bolts, staples or the like.

[0021 ] Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.

-52016102421 31 Mar 2016 [0022] As with the outlet housing, the adapter may also be manufactured as a single complete unit or in multiple parts which are assembled for use.

[0023] According to a third aspect of the invention, there is provided a pre-fabricated formwork and pipe work assembly comprising the lost formwork system of the second aspect of the invention with a pre-installed pipe and elbow assembly fully located therein. Preferably, the pipe includes an elbow at one end and connections means at the other such as a threaded section.

[0024] In preferred forms the pipe will be threaded at both ends with the elbow secured to the outlet end.

[0025] Desirably, the conduit length is sized to accommodate the pipe in the final intended installed position with the connection means of the free end of the pipe extending there from.

[0026] More preferably, the outlet housing is configured such that the pipe can be located fully within the formwork in an installation position with the elbow offset from the first axis and the remote end of the pipe within the conduit and/or adaptor, and then moved post installation to an in-use configuration with the elbow aligned with the first axis and the distal end of the pipe extending beyond the formwork.

[0027] An optional end cover may be applied to the pipe outlet to prevent ingress of cement slurry during the concrete pour.

[0028] According to a fourth aspect of the invention there is provided a method of installing a pipe work assembly for fire control applications and the like within a cast concrete slab, the method including the steps of:

securing an outlet housing according to the first aspect of the invention to a predetermined position on the formwork defining the outlet surface at the desired outlet location;

installing a box former at a predetermined connection location remote from the outlet location, the box former having a formwork surface facing, but transverse to, the outlet surface;

connecting a first end of a pipe receiving conduit to the second outlet of the outlet housing and a second end to a support formed on or in the transverse surface of the box former; and pouring the slap to thereby encase the pipe work.

-62016102421 31 Mar 2016 [0029] In some embodiments the second pipe end support may simply comprise a hole formed in the wall of the box former. In others a special adapter may be used of the kind described above which can be secured to the side of the box former form board without causing any penetrations.

[0030] Preferably, the first outlet of the outlet housing is located and supported via a form board mountable deck box sleeve of the kind commonly used for down lights and the like.

[0031 ] Where the formwork is installed first, and the pipe and fittings are installed after the slab has been cured and stripped, the elbow is inserted into the first outlet and held in position, and the pipe inserted from the end of the conduit remote the outlet and secured in an appropriate manner. If the connection is a threaded connection then the elbow is held still and the pipe rotated from the remote end to effect the connection.

[0032] In an alternative method, a pre-fabricated formwork and pipe work assembly comprising the lost formwork system of the second aspect of the invention, with a pre-installed pipe and elbow assembly fully located therein, is secured to the slab formwork in the manner described, with the elbow end of the pipe and elbow assembly located as far into the chamber away from the second outlet as possible. For embodiments where the housing has a primary chamber and a separately defined secondary chamber, the pipe end and elbow assembly is pushed into this secondary chamber such that the distal end of the pipe which extends from the conduit and optional adaptor, is fully retained within the assembly.

Brief description of the drawings [0033] Preferred embodiments of the invention will now be described, by way of example only, with reference to the following drawings in which:

[0034] Figure 1 is a perspective view of a first embodiment pipe end and elbow outlet housing according to the first aspect of the invention together with a first embodiment optional end adaptor;

[0035] Figure 2 is a vertical section of the outlet housing of Figure 1 taken on line A-A showing a pipe, elbow and sprinkler body therein and connected pipe conduit;

[0036] Figure 3 is a sectional plan view taken of the outlet housing of Figure 1 taken on line B-B;

-72016102421 31 Mar 2016 [0037] Figure 4 is a vertical section of the adaptor of Figure 1 taken on line A-A showing a pipe connection end and connected pipe conduit;

[0038] Figure 5 is an end view of the adaptor shown in Figure 4;

[0039] Figure 6 is a sectional view of a typical balcony slab arrangement with a first embodiment pre-fabricated formwork and pipe work assembly shown in the installation configuration with slab formwork; and [0040] Figure 7 is a sectional view of a typical balcony slab arrangement with a first embodiment pre-fabricated formwork and pipe work assembly as in Figure 6 but shown in the operational configuration.

Preferred embodiments of the invention [0041] Referring to the Figures there is a illustrated a first embodiment outlet housing 1 for concrete encasement of a pipe end with elbow fitting for a sprinkler body, with an optional end adaptor shown generally at 2.

[0042] The outlet housing 1 defines an internal chamber shown generally at 3 which is sized to receive an end portion 4 of a pipe such as a water pipe 5, an elbow fitting 6 and a sprinkler body portion 7. In the preferred form illustrated the chamber includes a primary chamber 8 which is capable of housing all components 4 to 7, and a separately defined first secondary chamber 9 and optional second secondary chamber 10. Chambers 9 and 10 are sized to accommodate the pipe end 4 and elbow fitting 6 only as is described in more detail here after.

[0043] The housing and chamber or chambers has two outlets. The first is in the form of a first outlet 11 which in the preferred form is cylindrical with a distal end 12. This is sized to neatly accommodate a sprinkler body and associated fittings so as to define an outlet, which on installation will be flush with the ceiling from which the sprinkler head is to depend. This outlet has a first axis 13 which in use will be oriented generally vertically as shown.

[0044] The second outlet is adapted to receive and retain a pipe receiving conduit 14 and in the illustrated embodiments takes the form of a spigot 15. The spigot in this embodiment is configured to receive the conduit 14 internally and includes an internal lip formation 16 to act as a stop and end locator for the pipe 5. The spigot, pipe retaining conduit 14, and pipe 5 all share a common axis 17 which in use extends in a generally horizontal orientation as shown.

-82016102421 31 Mar 2016 [0045] The optional adaptor 2 has a body 18 that includes a conduit receiving inlet, preferably in the form of a further spigot 19. As with the spigot 15 on the outlet housing 1, this is similarly designed to receive the conduit internally and also includes an internal ledge or stop formation 20.

[0046] At the opposite end of the adaptor there is a pipe outlet 21 which is flared from the spigot 19 so as to provide adequate clearance around the pipe to provide easy access to the free end 22 of the pipe 5.

[0047] The adaptor 2 also includes means to secure the adaptor to the form work, which in this particular embodiment is in the form of a plurality of securing flanges 23 having apertures 24 to receive appropriate fasteners such as screws, nails etc.

[0048] Preferably the outlet housing 1 and adaptor 2 are made from a suitable plastics material and may be injection moulded or produced by any other suitable process. The outlet housing and adaptor may each be made as single integrally formed units, or manufactured from more simple components which are assembled for use. The pipe receiving conduit in the preferred form is standard plastic electrical conduit. For a typical galvanised black steel water pipe diameter of 27mm a 32mm diameter conduit is ideal.

[0049] While the dimensions will depend upon the pipe sizes and dimensions of particular sprinkler fittings for which the system is designed, typical dimensions that work well for fittings that are currently available are as follows.

[0050] For the outlet housing, the first outlet 11 preferably has an internal diameter of 61 mm and an external diameter of 65mm. The spigot 15 preferably has an internal diameter of 32mm and an external diameter of approximately 36 mm. The first secondary chamber 9 ideally extends about 45 mm from the primary chamber 8 and the second secondary chamber extends about 15mm in the opposite direction. Preferably the lowermost surface of the conduit is located a distance of around 60mm from the distal end 12 of the outlet 11.

[0051 ] A preferred method of installation of a balcony fire control pipe work system utilising the preferred form of the invention will now be described with particular reference to Figures 6 and 7.

-92016102421 31 Mar 2016 [0052] Firstly the length of pipe receiving conduit 14 is connected at a first end to the spigot of the outlet housing 1 and at the other end to the spigot 19 of the adaptor 2. The joints may be sealed with a suitable adhesive if required.

[0053] The pipe 5, which is threaded at the ends as shown at 25, is then inserted in through the adapter inlet 21, down through the conduit 14 into the primary chamber 8 of the inlet housing 1. An elbow 6 having internal threads corresponding to those provided on the pipe ends is then presented into the chamber 8 via the first outlet 11 and the pipe connected by rotating the pipe 5 about its free end 22 until the connection is achieved.

[0054] The free end of the pipe 22 is then pushed into the formwork assembly defined but he inlet housing, conduit and adaptor until the elbow 6 is located in the secondary chamber 9 as shown in Figure 6. This prefabricated assembly is then secured to the [0055] The formwork for the building slab will already have been prepared and will include horizontal form board ‘IT defining in one region a lower surface 26 of the balcony, and in another a concealed internal ceiling surface 27. Intermediate these two regions is where the wall or window or door extends shown generally at 28 which separates the internal area of the adjacent room 29 from the balcony area 30. A box former will have been provided in the internal region which has a vertical form board ‘v’ which defines a transverse generally vertical surface of the final slab shown at 31.

[0056] The end of the prefabricated assembly including the adaptor 2 can be secured to the vertical portion V of the box former in the adjacent room 29 that defines the vertical surface 31 via the mounting flanges 23 retained with suitable fasteners through the apertures 24. At the outlet housing end, this is preferably secured by first connecting a deck box sleeve of the kind commonly used to cast apertures for down lights and the like (not shown) to the horizontal form board ΊΤ at the desired position, and then inserting the outlet 11 into this sleeve thereby also capping the outlet opening. The outlet 11 is designed to achieve a close fit with the sleeve to prevent egress of slurry during the slab pouring process.

[0057] Once the prefabricated assembly is secured, and the remaining internal slab elements are in place, the slab can be poured and finished in the usual manner. After adequate curing of the concrete has taken place, the external formwork defining the slab peripheral surfaces is removed. The inlet housing 1, conduit 14 and adaptor 2 remain captive

- 102016102421 31 Mar 2016 within the concrete thereby forming part of the final structure thereby becoming what is often referred to as lost formwork”.

[0058] To complete the installation, the pipe end 22 is pulled out from the adaptor outlet 21 via the pipe end 22 and appropriate connections made at that end to supply pipe work inside the building. If required the elbow 6 can be drawn into the second secondary chamber 10 thereby exposing more of the pipe end to facilitate connections.

[0059] Once this has been completed, the pipe is pushed back into the formwork along the second axis 17 towards the outlet housing until the vertical axis of the elbow 6 is generally in line with the first vertical axis 13 of the outlet 11. At this location the sprinkler body 7 and other sprinkler components can be secured including any forms of cover plates or finishing fittings as may be needed.

[0060] While the embodiments described have utilised a specially designed adaptor for securing the pipe conduit at the end remote from the outlet housing, it will be understood that alternative arrangements may be substituted. For example that end of the conduit could be supported directly on the formwork, or the conduit could extend into or through an aperture provided in that formwork.

[0061 ] Furthermore, although there are clear advantages to the embodiment described that has specially configured secondary chambers 9 and 10 which maximise functionality while minimising overall volume of the formwork, other variations fall within the scope of the invention including those using a more uniform larger volume single chamber that still permits the same range of movement of the pipe and elbow, or smaller volume chamber configurations, which while not enabling the same degree of movement, may none the less provide significant advantages over the prior art to date. In such embodiments, the method of installation may vary whereby the elbow and/or pipe cannot be secured to the pipe until after the formwork has been encased.

[0062] It will be appreciated that the invention, particularly in the preferred form, offers significant advantages over the prior art. For example the system in all forms obviates the need to provide any additional finishing post installation, and the precisely configured outlet 11 of the outlet housing provides a neat and accurate opening for the sprinkler heads. This is particularly advantageous where concealed sprinkler systems are to be used of the kind where

- 11 2016102421 31 Mar 2016 the sprinkler outlet is flush with the ceiling after installation and the sprinkler heads only drop down from covers when activated.

[0063] Furthermore, volumetric optimisation of the void in which the pipe work extends, means that there is a minimum impact on the structural integrity of the slab and can be readily incorporated without major slab redesign. In addition the sizing and configuration enables sufficient concrete cover over the piping formwork (in the order of 60mm) so as not to compromise protection of the internal steel reinforcement in the slab.

[0064] Additionally, the system is modular and readily configured for use on different sites. Also, by enabling prefabrication of the pipe work and formwork in preferred embodiments, there can be substantial time savings and minimisation of trade times needed on site. It also means that components can be accurately cut to size in advance thereby improving consistency of outcome and quality of installation.

[0065] Finally, while the invention has been described with reference to various embodiments, sizes, materials and specific forms and uses, it will be appreciated by those skilled in the art that the inventive concepts may be embodied in many other forms not limited by the specific disclosure herein.

Claims (18)

1. Claims

   1. According to a first aspect of the invention, there is provided an outlet housing for concrete encasement of a pipe end with elbow fitting for a sprinkler body, the housing including:

   a chamber sized to receive a pipe end with elbow fitting and a sprinkler body;

   a first outlet from the chamber configured to provide an opening sized to neatly accommodate a sprinkler body, the first outlet having a first axis; and a second outlet from the chamber adapted to receive and retain a conduit through which the pipe with the pipe end can extend, the second outlet having a second axis.
2. 2. An outlet housing according to claim 1 wherein the chamber is sized to facilitate a predetermined amount of translational movement of the pipe and elbow assembly along the second axis to one or both sides of the first axis.
3. 3. An outlet housing according to claim 2 wherein the chamber includes a primary chamber that extends about the first axis that will accommodate the elbow and sprinkler body, with one or two smaller secondary chambers that extend about the second axis sized only to accommodate the pipe and elbow.
4. 4. An outlet housing according to any one of the preceding claims wherein the first outlet is generally cylindrical and extends from a central portion of the chamber.
5. 5. An outlet housing according to claim 4 wherein the inner diameter of the cylindrical outlet is sized to neatly accommodate a sprinkler body of a conventional fixed head sprinkler, or sprinkler body with drop down sprinkler head assembly of the kind that are flush mounted at installation and only drop down into the space below once activated.
6. 6. An outlet housing according to claim 4 or claim 5 wherein the outer diameter of the cylindrical outlet is sized to seat closely within a standard form board mountable deck box sleeve of the kind commonly used in concrete construction for casting apertures for down lights and the like.
7. 7. An outlet housing according to any one of the previous claims wherein the second outlet is in the form of a hollow spigot adapted to receive a suitably sized conduit for the pipe.

   - 132016102421 31 Mar 2016
8. 8. An outlet housing according to any one of the preceding claims constructed from two or more separately made components which are assembled for use.
9. 9. A modular lost formwork system for concrete encasement of fire control pipe work, the system including:

   an outlet housing for concrete encasement of a pipe end with elbow fitting for a sprinkler body according to any one of the preceding claims; and a length of pipe receiving conduit connected to the second outlet.
10. 10. A modular lost formwork system according to claim 9 wherein the system further includes an adapter to enable connection to the distal end of the pipe remote the outlet housing, the adapter having a body including;

    a conduit receiving inlet;

    a pipe outlet; and means to secure the adapter to formwork as required.
11. 11. A modular lost formwork system according to claim 10 wherein the body of the adaptor includes a region sized to provide adequate clearance around the pipe to provide easy access to an end of the pipe for moving the pipe if and when required.
12. 12. A modular lost formwork system according to claim 10 or claim 11 wherein the inlet is in the form of a spigot configured to sit over the pipe receiving conduit.
13. 13. A modular lost formwork system according to any one of claims 10 to 12 wherein the means to secure the adapter to formwork comprises one or more flanges with apertures for receiving appropriate fasteners such as nails, screws/bolts, staples or the like.
14. 14. A pre-fabricated formwork and pipe work assembly comprising the lost formwork system of any one of claims 9 to 12 with a pre-installed pipe and elbow assembly fully located therein.
15. 15. A pre-fabricated formwork and pipe work assembly according to claim 14 wherein the conduit length is sized to accommodate the pipe in the final intended installed position with the connection means of a free end of the pipe extending there from.
16. 16. A pre-fabricated formwork and pipe work assembly according to claim 14 or claim 15 wherein the outlet housing is configured such that the pipe can be located fully within the

    - 142016102421 31 Mar 2016 formwork in an installation position with the elbow offset from the first axis and the remote end of the pipe within the conduit and/or adaptor, and then moved post installation to an in-use configuration with the elbow aligned with the first axis and the distal end of the pipe extending beyond the formwork.
17. 17. A method of installing a pipe work assembly for fire control applications and the like within a cast concrete slab, the method including the steps of:

    securing an outlet housing according to any one of claims 1 to 8 to a predetermined position on the formwork defining the outlet surface at the desired outlet location;

    installing a box former at a predetermined connection location remote from the outlet location, the box former having a formwork surface facing, but transverse to, the outlet surface;

    connecting a first end of a pipe receiving conduit to the second outlet of the outlet housing and a second end to a support formed on or in the transverse surface of the box former; and pouring the slap to thereby encase the pipe work.
18. 18. A method of installing a pipe work assembly according to claim 17 wherein the second pipe end support may simply comprise a hole formed in the wall of the box former. Preferably, the first outlet of the outlet housing is located and supported via a form board mountable deck box sleeve of the kind commonly used for down lights and the like.