Technical Field

The following invention relates to the field of pipes and pipe connectors, and more specifically the invention relates to guides and locators for pipes. The invention further relates to a method of constructing soil pipes for buildings.

Background

In both domestic and industrial buildings there is a requirement to remove both sewage (soil) and grey water and to feed such waste into the sewer network. Typically, this is achieved by a drain-waste-vent system, a major component of which is the soil stack. A soil stack is a large diameter vertical pipe which acts as a common waste pipe in to which the other soil and grey water pipes from the building feed and which connects to the sewer at or below ground level.

To simplify installation in some construction projects, pre-plumbed units (pods) such as complete bathroom suites can be provided. The pods can be quickly placed in the desired location within the building, for example by hoisting them into position with a crane to provide a bathroom suite, without requiring extensive installation time. The pods are then simply connected to the building’s water supply and waste plumbing to form fully plumbed and functional suites. Although the pods reduce the amount of plumbing and installation required on site, it can often be difficult to reliably and securely connect the pod plumbing to the building and/or mains plumbing.

Summary of Invention

One current problem with using pre-plumbed pods during construction is the difficulty in connecting the pod plumbing to the building plumbing. Depending on the building and the pod configurations, the plumbing connections may be hidden between the pod walls and the building walls, or alternatively, the plumbing connections may be hidden within the pod itself. A further problem is that aligning the pod plumbing with the building plumbing on the floors above and/or below can be challenging. According to a first aspect of the invention, there is provided a pipe connector for a soil pipe. The pipe connector may comprise a socket portion. The socket portion may be configured to receive a pipe therein for sealing with said pipe. The pipe connector may comprise a guide portion. The guide portion may comprise an angled surface for guiding a pipe into the socket portion.

The angled surface may extend from the socket portion. The angled surface may comprise a mouth wherein the mouth has a greater diameter and/or cross-sectional area than the socket portion. The guide portion may comprise a funnel. In some embodiments, the guide portion and the socket portion may be integrally formed. For example, the guide and socket portions may be integrally moulded.

The angled surface may extend to an open end of the pipe connector, distal to the socket section. The angled surface may be constantly angled around the pipe connector, relative to a rotational axis of the pipe connector. Alternatively, the angle may alter, rotationally around the axis, axially from open end to socket section, or both. For example, the angle to the rotational axis may decrease from the open end to the socket section, to produce a flared opening. This may serve to provide both initially coarse relative lateral positioning of the soil pipe to the followed by fine positioning of the soil pipe as it is lowered into the pipe connector.

The angled surface may have an angle between 5° and 45° relative to the axis of the pipe connector. The angled surface may be at least 10°, at least 15°, at least 20°, at least 25° or at least 30°. The angled surface may be less than 40°, less than 35°, less than 30°, less than 25° or less than 20°. Preferably, the angled surface is between 25° and 35°. More preferably, the angled surface is 30° relative to the axis of the pipe connector. The above angles (and particularly 30°) are effective at guiding a pipe toward the socket portion while still providing a significantly larger opening at the distal end of the guide portion.

The mouth of the angled surface may have a cross-sectional area greater than the cross-sectional area of the socket portion. For example, the cross-sectional area of the mouth may be at least 1.25, 1.5, 1.75 or at least 2 times the cross-sectional area of the socket portion. The socket portion may have a diameter approximately the same and/or slightly greater than the external diameter of a soil pipe. For example, the socket portion may be configured to receive a conventional soil pipe, for example, a 56mm, 75mm, 82mm, 110mm, or 160mm diameter soil pipe.

In one series of embodiments, the socket portion further comprises a sealing means for sealing against the exterior surface of a pipe inserted into the socket portion. The sealing means may comprise at least one heater coil for electrofusion or induction heating. The at least one heating coil may further comprise at least one electrical connector located on the exterior of the socket portion.

Additionally or alternatively, the sealing means may comprise at least one gasket, flexible seal or compression seal. The socket portion may comprise a recess for housing a portion of the seal or gasket. The recess may be provided within a wall of the socket portion. The recess may comprise an annular recess extending around the internal surface of the socket portion, and wherein the seal or gasket comprises an annular seal or gasket.

The pipe connector may further comprise a tail portion for connecting to a soil pipe. The tail portion may extend from the socket portion. The tail portion may be provided on the opposite end of the socket portion, relative to the guide portion. The tail portion may be configured to be the same size and/or shape as a conventional soil pipe. For example, the tail portion may be configured to have the same size and shape as a a 56mm, 75mm, 82mm, 110mm, or 160mm diameter soil pipe.

The tail portion may comprise a surface for sealing to a soil pipe. The tail portion may be sealed to a soil pipe by any suitable method. For example, the tail portion may be joined to a soil pipe by any one or more of plastics welding, adhesion with an adhesive, or one or more mechanical fasteners. Plastics welding may comprise any one or more of butt welding, electrofusion welding, solvent welding, ultrasonic welding, induction welding, friction welding, laser welding, IR welding or Radio Frequency (RF) welding. Butt welding and electrofusion are particularly advantageous, since they are reliable and inexpensive processes. Friction welding is particularly advantageous, since the pipe connector and soil pipe may be rotated relative to each other and pressed together to form a friction weld. The pipe connector may be formed from a plastics material. The branch connector may be formed from High Density Polyethylene (HDPE). Alternatively, the branch connector may be formed from PVC, polypropylene, polybutylene, ABS, low or medium density polyethylene, or other suitable plastics material.

According to a second aspect of the invention, there may be provided a kit of parts for connecting soil pipes. The kit may comprise a pipe connector as described above. The kit may further comprise a pipe extender portion. The pipe extender portion may comprise an elongate pipe body and a second socket portion. The second socket portion may be configured to receive a pipe therein for sealing with said pipe. The second socket portion may be provided at a first end of the pipe body. Optionally, a second end of the pipe body may be provided with a tapered surface. The pipe body of the pipe extender portion may be configured to be receivable within the socket portion of the pipe connector.

According to a third aspect of the invention, there is provided a method for connecting soil pipes. The method may comprise: providing a pipe connector as described herein. The method may comprise: inserting a pipe through the guide portion into the socket portion. The method may comprise: sealing the socket portion to the pipe.

The method may further comprise sealing the pipe connector to a further soil pipe via the tail portion, prior to the method for connecting soil pipes described above.

According to a fourth aspect of the invention, there is provided a method for connecting soil pipes. The method may comprise: providing a kit of parts as described herein. The method may comprise: sealing the pipe extender portion to a soil pipe. The method may comprise: inserting the pipe extender portion through the guide portion into the socket portion of the pipe connector. The method may comprise: sealing the socket portion to the pipe extender portion.

The method may further comprise sealing the pipe connector to a further soil pipe via the tail portion, prior to the method for connecting soil pipes described above. In the third and fourth aspects, sealing the socket portion to the pipe and/or pipe extender portion may comprise any suitable sealing process. For example, sealing the socket portion to the pipe and/or pipe extender portion may comprise any one or more of plastics welding, adhesion with an adhesive, or one or more mechanical fasteners. Plastics welding may comprise any one or more of butt welding, electrofusion welding, solvent welding, ultrasonic welding, induction welding, friction welding, laser welding, IR welding or Radio Frequency (RF) welding. Butt welding and electrofusion are particularly advantageous, since they are reliable and inexpensive processes.

According to a fifth aspect of the invention, there is provided a method of constructing a plumbing system comprising: providing a first pre-plumbed pod comprising a first soil stack portion, the first soil stack portion comprising a pipe connector as described herein; providing a second pre-plumbed pod comprising a second soil stack portion; and connecting the second soil stack portion to the first soil stack portion by inserting an end of the second soil stack portion into the pipe connector of the first soil stack portion.

The method may comprise installing the first pre-plumbed pod into a building. The first soil stack portion may be connected to the pre-plumbed pod prior to, or after, installing the pre-plumbed pod into the building. Connecting the first soil stack portion may comprise connecting at least one waste pipe in the pre-plumbed pod to a branch connector in the first soil stack portion.

The method may comprise installing the second pre-plumbed pod into the building. The second soil stack portion may be connected to the pre-plumbed pod prior to, or after, installing the pre-plumbed pod into the building. Connecting the second soil stack portion may comprise connecting at least one waste pipe in the pre-plumbed pod to a branch connector in the second soil stack portion.

Connecting the first and second soil stacks may be carried out simultaneously with the second pre-plumbed pod being installed into the building. The method may comprise moving the second pre-plumbed pod in the axial direction relative to the first soil stack portion. E.g. the method may comprise lowering the second pre-plumbed pod onto or above the first pre-plumbed pod. In some embodiments, the second pre-plumbed pod is installed vertically above the first pre-plumbed pod e.g. on the floor of the building above. The method may comprise aligning the first and second pre-plumbed pods so that the second soil stack portion is inserted into the pipe connector as the second pre- plumbed pod is being lowered.

The method may comprise connecting a pipe extender portion to the second soil stack portion prior to connecting with the first soil stack portion. The method may comprise inserting the pipe extender portion into the pipe connector.

Optionally, the second soil stack portion may comprise a second pipe connector as described herein. The method may further comprise connecting the second soil stack portion to a third or greater soil stack portion.

Brief Description of the Figures

Embodiments of the invention will now be described with reference to the following figures in which:

Figure 1 is a perspective view of a conventional soil stack;

Figures 2a-2d are cross-sections through pipe connectors of embodiments of the present invention;

Figures 3a-c are cross-sections through pipe connectors of embodiments of the present invention during an assembly process of a soil stack;

Figure 4 is a perspective view of connected soil pipes of embodiments of the present invention; and

Figure 5 is a perspective view of a soil stack using the pipe connectors of embodiments of the present invention.

Specific Description

As used herein, relative descriptions such as upper or uppermost and lower or lowermost are with reference to the enclosed Figures only and for ease of description and clarity, and should not be viewed as limiting upon the invention and embodiments described. Turning now to Figure 1, there is shown a pre-assembled, conventional soil stack 1. The soil stack 1 is a branched pipe formed from multiple pre-installed branches 2 or connections for connecting to a building’s waste plumbing system, e.g. the waste outlets from sinks, toilets and showers etc. The lower end of the soil stack 1 is connected to the sewer network, and thus waste water flows into the soil stack from the branches 2, and travels downwards into the sewer system.

The upper end of the soil stack 1 is provided with an expansion coupling 3. The expansion coupling 3 connects to a further length of pipe or pipe connector as required to extend the overall length of the soil stack 1. The lower end of the soil stack 1 can be connected to a coupling (such as the expansion coupling 3) of a lower section of plumbing or the sewer network, or alternatively it could be permanently connected to a lower pipe via welding or other process.

Turning now to Figures 2a to 2d, there are shown a series of cross-sections through embodiments of pipe connectors (30a to 30d). In each of the embodiments shown, the numbering will be kept consistent between equivalent features.

In Figure 2a, the pipe connector 30a comprises a guide portion 31, a socket portion 33, and a tail portion 35. The guide portion 31 has an angled surface. In the embodiment shown, the guide portion 31 forms a funnel with a tapering cross-section. The guide portion 31 has a mouth 32 with a first diameter and narrows toward the socket portion

33, which has a smaller diameter than the mouth 32. The end of the guide portion 31 immediately adjacent to the socket portion 33 is open and thus the guide portion 31 has a frusto-conical shape.

The socket portion 33 is a region of straight pipe, with an inner diameter equivalent to the lower end of the guide portion 31, so as to form a guide shoulder 34 therebetween. The socket portion extends in a straight line with straight sides from the guide shoulder

34, and connects to the tail portion 35. The inner diameter of the socket portion 33 is configured to be slightly greater than the external diameter of a conventional soil pipe, so that a soil pipe can be received within the socket portion 33. The tail portion 35 is a further portion of straight pipe. The tail portion 35 extends coaxially from the socket portion 33. The tail portion 35 is sized (e.g. has a diameter and wall thickness) to match the size of a soil pipe. For example the tail portion 35 is a short length of 110mm diameter soil pipe. Alternatively, the pipe connector can be provided in any other size (not shown) common sizes including: 56mm, 75mm, 82mm, or 160mm diameter soil pipes. Since the tail portion 35 has a diameter smaller than the socket portion 33, a tail shoulder 36 is formed between the tail portion 35 and socket portion33. The tail shoulder 36 can be a short tapering section as shown in Figure 2a, or it can be formed by a sharp corner as shown in Figure 2b, or as discussed below. The lower end of the tail portion 35 is configured for connection to a further soil pipe (not shown). The tail portion 35 can be connected by any conventional means for joining two pipes, e.g. with a coupling or connector, or alternatively by welding or adhering to a further soil pipe. In the embodiment shown, the tail portion 35 is squared off for butt welding or friction welding to a further soil pipe. The tail portion 35 is also provided with a ridge 37 which can be used to locate a wall bracket (not shown) to support an assembled soil stack in use and form a fixed anchor point.

In some embodiments (not shown), the tail shoulder 36 may be a smoothly curving region between the socket portion 33 and the tail portion 35. In other embodiments, the socket portion 33 may be provided with a tapered cross section, narrowing from the guide portion end to the tail portion end and thus the tail portion 35 is provided by the lowermost end of the tapered socket portion 33.

The pipe connectors 30a, 30b are thus substantially the same as the pipe connectors 30c, 30d, but are provided with longer socket portions 33 and tail portions 35 (in the axial direction). The longer socket portions are thus better able to accommodate expansion and contraction of the soil stack, either during installation or in use.

In each of the pipe connectors 30a-30d, the socket portion 33 is provided with a sealing means 39. The sealing means 39 is provided adjacent to the guide portion 31 e.g. at the upper end of the socket portion 33 in use. In Figure 2a, pipe connector 30a has a gasket 39a received with an annular recess extending around the internal surface of the socket portion 33. The gasket 39a can be any suitable form of seal, but is preferably a flexible ring seal. In figures 2b and 2c, the pipe connectors 30b, 30c also have sealing means 39 comprising a gasket 39a and an electrofusion welding portion 39b. The electrofusion welding portion comprises a heating wire embedded within the internal surface of the socket portion. The heating wire is connected to a pair of power connectors 39c located on the exterior surface of the pipe connector 30b. The electrofusion welding portion 39b is located between the guide portion 31 and gasket 39a i.e. the gasket 39a is the lowermost component of the sealing means 39. In figure 2d, the sealing means 39 comprises just an electrofusion welding portion. It is thus envisaged that the sealing means 39 can be formed in various different configurations and selected depending on intended use and installation requirements.

In use, the pipe connectors 30a-d are connected to the uppermost end of a soil stack e.g. replacing the expansion coupling 3 of Figure 1. Connecting the tail portion 35 to a pipe may comprise any one or more of plastics welding, adhesion with an adhesive, or one or more mechanical fasteners. Plastics welding may comprise any one or more of butt welding, electrofusion welding, solvent welding, ultrasonic welding, induction welding, friction welding, laser welding, IR welding or Radio Frequency (RF) welding. Butt welding and electrofusion are particularly advantageous, since they are reliable and inexpensive processes. In some embodiments, the tail portion will be friction welded to a pipe, for example, by rotating the pipe connector and a pipe relative to one another at high speed and pressing them together. Preferably, the pipe connector 30 is connected to a pipe in advance of installation on site, thus providing preformed portions of a soil stack. Once the pipe connector 30 is connected to a pipe by the tail portion 35, it can be used to connect to a further pipe or soil stack portion as described with reference to Figures 3a to 4.

Figures 3a to 3c show sequential stages in a process of connecting two pipes. Figure 3a shows a lower end of a conventional soil pipe 10.

Figure 3b shows an optional intermediate step. A pipe extender portion 20 is provided, formed of a straight extender pipe portion 21 and an extender socket 22. The extender socket 22 is configured to receive the soil pipe 10 and seal thereto. In the embodiment shown, the extender socket 22 is provided with an electrofusion end comprising a heating wire (not shown) and electrical connectors for electrofusion welding the extender socket 22 to the end of the soil pipe 10 received within the extender socket 22. At the opposite end of the extender portion 20 the outer surface of the extender pipe portion 21 is provided with a chamfered outer edge 23 to assist location of the pipe extender 20 in the next step of the connecting process.

Figure 3c shows a soil pipe 10 with a pipe extender 20 sealed thereto, and a pipe connector 30 as shown in Figure 2b. It will be understood that any of the pipe connectors 30a-30d may be used in the same manner. The soil pipe 10 and extender 20 are then moved downwards through the pipe connector 30 so that the pipe extender 20 passes through the guide portion 31 and into the socket portion 33. The leading end of the pipe extender 20 thus passes through the sealing means 39 and rests at some point between the sealing means 39 and the tail shoulder 36. The tail shoulder 36 can thus act as an abutment to prevent the pipe extender from being inserted too far into the pipe connector 30, although it is not necessary for the pipe extender 20 to be inserted all the way up to the tail shoulder 36. Once the pipe extender is located within the socket portion, the heating wire of the sealing means 39 can be operated to seal the socket portion 30 to the pipe extender 20 via an electrofusion weld. The completed pipe connection is shown in Figure 4.

It will be appreciated that the pipe extender portion 20 is an optional component, and it is also possible to use the pipe connector 30 directly with a soil pipe 10 in the same manner. The pipe extender portion 20 is particularly useful in installations where it is desired to connect the soil stack between floors, and an additional length is required to span the depth of the floor slab itself.

Turning now to Figure 5, there is shown a soil stack which is formed from discrete sections connected by the pipe connector described above. The soil stack connects a series of pre-plumbed pods 5a-c across three floors of a building. The soil stack comprises a series of soil pipes 10a-c, each pipe 10 being the length of a single floor of the building. The lowermost end of each soil pipe 10 is provided with a pipe extender portion 20a-c as described previously. The pipe extender portion 20 is then sealed to the soil pipe below it via pipe connectors 30 of the type described above.

The process of installation first requires positioning of the pods 5 in the desired location of the building. In some processes, the pods 5 will have the soil pipe 10 pre-installed and fluidly connected to the pod plumbing 11. Alternatively, the soil pipe sections can be fitted to the pods 5 once in place and then subsequently connected together to form the soil stack. If the pods have the soil pipe 10 pre-installed, it is possible to construct the soil stack at the same time as positioning the pods.

In a first example process, the pods 5a-c are all positioned in the desired location within the building. A soil pipe 10a is then attached to the first pod 5a and connected to either a sewer of lower section of soil pipe (not shown). This can be achieved with a pipe extender 20a as pictured, or by joining the soil pipe 10a directly to the sewer or lower section of soil pipe. The soil pipe 10a is then connected to the pod plumbing 11.

Then, a soil pipe 10b can be attached to the second pod 5b. The lowermost end of the soil pipe 10b is connected to the soil pipe 10a by the pipe connector 30a in the manner described above. As shown in Figure 5, the soil pipe 10b is provided with a pipe extender 20b to span the depth of the floor, although it is possible to connect the end of the soil pipe 10b directly without using a pipe extender 20b. The pipe connector 30a can then be sealed, for example, via electrofusion welding in embodiments with heating wires, to the soil pipe 10b to make a permanent seal. The whole process can be repeated with the third pod 5c and soil pipe 10c, and optionally greater numbers depending on the number of floors.

In an alternative process, wherein the soil pipes 10 are pre-installed on the pods, the soil stack can be assembled as the pods 5a-c are being positioned. In such a process, the first pod 5a is located in position and the soil pipe 10a connected to the sewer or a lower soil pipe (not shown). The floor above the pod 5a is then constructed and the second pod 5b is positioned. Since the pod is likely to be hoisted in with a crane, while the pod 5b is in the air, the pipe extender portion 20b can be connected and sealed to the lower end of the soil pipe 10b. As the pod 5b is lowered into position, the pipe extender 20b is inserted into the pipe connector 30a, and thus once the pod 5b is in position on the floor, the soil pipes 10a and 10b will be connected and can be sealed in embodiments requiring plastics welding. Again, this process can be repeated with each subsequent floor to construct a soil stack of the desired length.

With additional reference to Figures 3a to 3c, the invention is particularly advantageous, since the difficulties of connecting a soil stack between floors and between pods is simplified by use of the pipe connectors 30. The guide portion 31 makes it far simpler to insert the soil pipe 10 or pipe extender 20 into the pipe connector and thus ensure a satisfactory alignment. In existing systems it is necessary to join two lengths of pipe with conventional couplings or by welding the pipes together. This leaves very little margin for error, and is very difficult to achieve while attempting to position a large pre-plumbed pod.

The invention may find further use in a process of retrofitting a building with a new soil stack, known as a ‘live stack replacement’. Older buildings will already have a soil stack in situ connected to the rest of the buildings plumbing. However, at some point the soil stack will come to the end of its usable life and require replacing, especially in older cast iron systems which have corroded over time. Replacing the soil stack is particularly difficult in occupied buildings (such as apartment blocks) where it is not practical to have all of the building’s plumbing inactive while the soil stack is replaced. Thus, the present invention allows for live stack replacement wherein the soil stack can be replaced sequentially in segments, and quickly and reliably join each segment together, without requiring an extended period out of service.

For example, the lowermost portion of soil stack can be cut out while retaining all of the soil stack on the floors above. A soil pipe (as described with reference to Figure 5) can be connected to the upper plumbing by using the pipe connector 30 of the present invention. Pipe connectors 30a, 30b as described in Figures 2a and 2b are particularly useful, since the elongated socket portion 33 permits axial movement of the soil pipe 10 during installation without breaking the seal of the gasket 39a with the upper soil stack. The lower end can be connected to a sewer or further soil pipe in the conventional manner. Then the process can be repeated with the portion of the soil stack on the floor above. Once the floor above has been replaced, the two new sections of soil pipe can be permanently sealed together, for example, by plastics welding the two parts such as by electrofusion welding using the heating wires 39b.

The sealing means 39 of the invention are particularly useful, since they allow for simple sealing of the two pipes together. The provision of a gasket 39a and electrofusion welding portion 39b is particularly advantageous, since the gasket 39a can provide a temporary seal to the soil stack, for example, during live stack replacement. The gasket 39a acts to seal against the soil pipe and prevent water ingress through capillary action between the walls of the soil pipe and socket portion 33. Thus it is only necessary to prevent use of the soil stack while the old section is being cut out. Since the gaskets can be used to seal each end of the new pipe section, there will be no problem with a person on a floor above flushing a toilet or draining a sink. Thus the amount of ‘down time’ for the soil stack can be minimised and disruption to the building occupants is reduced.

Furthermore, as described above, the soil pipe 10 terminates between the gasket 39a and the tail shoulder 36. The gasket 39a thus prevent any water from getting into the region of the sleeve 33 wherein the electrofusion welding portion 39b is provided. This ensures that both the electrofusion welding portion 39b and the soil pipe to which it is to be connected are dry during welding and thus improving the quality of the weld.