GB2579130A

GB2579130A - Adjustable plumbing trap

Info

Publication number: GB2579130A
Application number: GB1913940.1A
Authority: GB
Inventors: Edward Mcalpine James
Original assignee: McAlpine and Co Ltd
Current assignee: McAlpine and Co Ltd
Priority date: 2019-09-27
Filing date: 2019-09-27
Publication date: 2020-06-10
Anticipated expiration: 2039-09-27
Also published as: WO2021058237A1; GB201913940D0; GB2579130B

Abstract

An adjustable trap with body 12 that has an inlet 16, an outlet 20 and first and second hollow sleeves 40 and 52. The second sleeve 52 is positioned within the first and slides to adjust the height of the trap. The second sleeve also houses components such as a shut-off valve 60 which move as the sleeve moves. The valve may be a duckbill valve 60 and the second sleeve may also have a hollow coupling device 64 which may be threaded and have a flange 66 which acts as a stop against an upper face of the sleeve. The upper section of the coupling may be designed to connect the trap to an outlet of a sanitary product. The outlet may have a threaded connector or a connector with a textured surface that engages with a snap-collar 122. The trap may be a bottle trap and the inlet and outlet may be perpendicular to one another. The base 14 may be removable.

Description

ADJUSTABLE PLUMBING TRAP

Field of the Invention

This invention relates to an adjustable plumbing trap, configured to provide an adjustable and versatile fit between a waste outlet from sanitaryware and associated pipework, which is operable to carry waste water from the sanitaryware. In particular, this invention relates to a compact and adjustable trap for use where space and accessibility below the sanitaryware product is restricted.

Background to the Invention

Bottle traps were primarily designed for ease of cleaning because the base of the trap unscrews from the body of the trap such that any foreign objects, which are not flushed away with waste water can be removed. This type of trap is particularly useful in commercial premises, such as hairdressing salons, hotels, leisure premises, etc. More recently, bottle traps have become increasingly used in various domestic and commercial applications, for example, on sinks, wash hand basins, baths and showers Like many traps the outlet of a bottle trap is typically arranged such that a water seal is created in the base of the trap. The water in the water seal is replaced each time waste water flows from the outlet of the sanitaryware to which the trap is attached, but a permanent water seal remains to prevent odours from the drainage system entering the room via the open outlet to which the trap is attached.

Recently, it has become more common to include a flexible shut-off valve within the body of the trap such that, in the event the water seal evaporates or is siphoned from the trap, the flexible shut-off valve facilitates containment of odours within the drainage system.

A suitable trap is typically connected to an outlet of a sanitaryware product and subsequent to connection bends and elbows are added to the outlet of the trap to facilitate connection of the drainage pipe system (connected to the waste e.g. the soil stack) to ensure a suitable, watertight/leak free connection between the drainage pipe system and the trap.

Summary of the Invention

According to a first aspect of the present invention there is provided a trap attachable to a waste outlet of a sanitaryware product, the trap comprising: a trap body including, an inlet port, an outlet port and a first hollow sleeve extending from the inlet port into the trap body and a second hollow sleeve, wherein a first end of the second hollow sleeve is received inside the first hollow is sleeve and a second end of the second hollow sleeve facilitates connection of the inlet port to the waste outlet of sanitaryware to which the trap is to be connected, wherein the second hollow sleeve is configured to slide relative the first hollow sleeve, thereby defining an adjustable neck, which moves relative to the inlet port to adjust the height of the trap; and wherein the second hollow sleeve houses an assembly of components, including a flexible shut-off valve such that the second hollow sleeve and the assembly of components, including a flexible shut-off valve all move as a unit when the second hollow sleeve is extended or retracted relative to the first hollow sleeve and the trap body.

Including an adjustable second hollow sleeve provides a versatile trap where the height can be adjusted to suit the available space in an installation situation and also relaxes the tolerances required between pipework and waste outlet, whilst ensuring a watertight seal every time because the locking the movable sleeve can be the last stage of installation.

By housing the flexible shut-off valve within the second hollow sleeve, the trap body and be reduced in size compared with conventional traps because the flexible shut-off valve is typically arranged in the trap body and there restricts the extent of extension and retraction of a hollow sleeve or pipe-fitting relative to the trap.

A trap according to the present invention optimises the space for fitting a trap to an outlet of a sanitaryware product and reduces the number of elbow or extension pieces or adjustments required to fit a trap in confined area. By reducing the dimension of the trap relative to the sanitaryware product also allows for the trap to be fitted discretely and to be less visible beneath or to the rear of a sanitaryware product.

The flexible shut-off valve may be a duckbill valve.

It will be appreciated that the position of the flexible shut-off valve/duckbill valve will be determined by the position of the second hollow sleeve relative to the first sleeve and the trap body, but the function of flexible shut-off valve/duckbill valve will remain constant and unaffected by its position.

The second hollow sleeve may further comprise a hollow coupling, which includes a lower section, a mid-section and an upper section, wherein the lower section includes a profiled outer surface which complements an inner surface of 25 the hollow sleeve, wherein engagement of the complementary surfaces is operable to retain the duckbill valve within the hollow sleeve. The lower section and at least an internal portion of the hollow sleeve include complementary external and internal threaded sections.

The mid-section may include a radially extending flange, which acts as a stop against an upper face of the hollow sleeve, such that when the coupling and hollow sleeve are engaged the flange limits how far the coupling can extend into the hollow sleeve.

The radially extending flange also determines how far the hollow sleeve can extend into the trap and into the first hollow sleeve. This ensures that flow within or through the trap is not impeded when the trap is arranged at its shortest length. The shortest length being when the mid-section radially extending flange is abutting an upper surface of the trap.

The upper section of the coupling is configured to connect the trap to an outlet from a sanitaryware product. The upper section may include a substantially smooth-walled tubular portion, a loose-fitting threaded collar and a retaining flange operable to retain the threaded collar on the coupling, wherein the threaded collar is located between the mid-section radially extending flange and the retaining flange. The threaded collar facilitates connection of the trap to a waste outlet of a sanitaryware product The second hollow sleeve may further comprise an insert member, which is configured to be received in an open end of the duckbill valve and includes a body shaped to prevent inversion of the duckbill valve if and when the duckbill valve is subject to backflow or associated pressures. An upper edge of the insert may include a radially extending flange, which rests on a corresponding radially extending flange inside the second hollow sleeve, interaction of the radially extending flanges locate and maintain the position of the duckbill valve relative to the second hollow sleeve.

The outlet port may include a threaded outlet connector, which is engageable with a threaded collar, which, when engaged provides a compression joint between the hollow sleeve and the trap body. It will be appreciated that when the compression joint is tightened movement of the hollow sleeve relative to the internal sleeve and the trap body is prevented and when loosened the hollow sleeve can slide relative to the first hollow sleeve and the trap body.

Alternatively, the outlet port may include a connector comprising a textured outer surface, which is engageable with a snap-collar including a complementary textured internal surface. It will be appreciated that when the snap-collar is engaged with the textured outer surface movement of the second hollow sleeve relative to the internal sleeve and the trap body is prevented.

The second hollow sleeve is dimensioned and moveable relative to the trap body such that a one size trap is adaptable to fit various plumbing installations, without requiring adaptors, elbows or extra lengths of pipe to be fitted to a waste outlet of a sanitaryware product and a trap.

When the second hollow sleeve is fully retracted the internal end of the second hollow sleeve is proximate the lowest point of the trap, but is spaced sufficiently from the lowest point of the trap such that flow is not impeded if the shortest trap dimension is required.

The second hollow sleeve is inserted as part of an assembly such that the flexible duckbill valve forms part of the adjusting component and such that the flexible duckbill valve maintains operational shape and function The trap may be a bottle trap, wherein the outlet port is arranged relative to the trap body and a base such that, in use, a water seal exists between a lowest point of the outlet port and the base.

Axes of the inlet pod and the outlet port may be perpendicular to one another.

Brief Description of the Drawings

An embodiment of the present invention will now be described with reference to the accompanying drawings in which: Figure 1 is an exploded view of a bottle trap for a waste outlet according to an embodiment of the present invention; Figure 2 and 3 are section views of the assembled bottle trap of Figure 1 showing a flexible valve in a closed position; Figure 4 is an exploded view of a bottle trap having the body of the trap is illustrated in Figure 1, but including a vent valve on the stem of the outlet; Figure 5 is a section view of the assembled bottle trap of Figure 4 showing a flexible valve in a closed position; Figure 6 is an exploded view of a bottle trap including a snap-collar and seal arrangement as an alternative to a compression fitting illustrated in figures 1 to 5; Figure 7a illustrates a section view of the assembled bottle trap of figure 6; and Figure 7b illustrates a detailed view of a snap-collar and seal arrangement included in figures 6 and 7a.

Detailed Description of the Drawings

Figures 1, 2 and 3 illustrate a compact bottle trap 10; compact relates to the height of the trap 10 i.e. the body of the bottle trap 10 is smaller and shorter than conventional bottle traps.

Figure 1 illustrates an exploded view of the bottle trap 10, such that each component forming the bottle trap 10 is visible and the interaction between components can be ascertained with reference to figure 1 and the description below. Figures 2 and 3 illustrate an assembly of the components, but each figure is shown in cross-section to more clearly illustrate interaction between the components making up the bottle trap 10.

The bottle trap 10 includes a body 12 and a detachable base or base-cup 14. The detachable base or base-cup 14, facilitates maintenance of the trap 10 after installation on a sanitaryware product (not illustrated). In the illustrated example, the base 14 and the body 12 are connected by complementary male is and female screw-threads.

The body 12 includes an inlet port 16, which is arranged opposite the base 14 i.e. in a vertical orientation of the trap 10. For example, when the trap 10 is resting on the base 14, the base 14 forms the bottom of the body 12 and the inlet port 16 is arranged as an opening through the top of the body 12. A threaded inlet connector 18 and threaded collar 19 extend from the inlet port 16 to facilitate adjustment and locking an inlet connector assembly 50 relative to the inlet port (as discussed further below). The inlet connector assembly 50 facilitates connection of the trap 10 to an outlet of a sanitaryware product (not illustrated). Additional features of the inlet connector assembly 50 are described further below.

The body 12 also includes an outlet pod 20, which is provided by an opening through the side of the body 12. An outlet connector 22 is provided by a short stem 24 and a threaded outlet connector 26; each extend from the outlet pod 20 and facilitate connection of the trap 10 to a waste drainage system (not illustrated).

In the illustrated example the outlet connector 22 includes a conventional compression fitting 23 operable to make a pipe-to-pipe connection.

Referring to figure 1, the outlet connector 22 includes a smooth walled inner pipe section 28, which extends from the outlet port 20. The inner pipe io section 28 is inside, and coaxial with, the outlet connector 26 and coaxial with the outlet port 20.

An annular gap 27 is defined between the surface of the inner pipe section 28 and the internal wall of the outlet connector 26. The gap 27 and the inner pipe section 28 are dimensioned to receive an end of a drainage pipe (not illustrated) is forming part of the drainage system (not illustrated) to which the trap is to be connected.

A sealed connection between the outlet connector 22 and the drainage pipe is facilitated by interaction of the compression fitting 23, the drainage pipe (not illustrated), the pipe section 28, a tapered seal 30, an anti-slip collar 32 and a zo threaded nut 34.

To attach the trap 10 to the drainage pipe (not illustrated), the threaded nut 34 is loosely fitted over the end of the drainage pipe (not illustrated) followed by the anti-slip collar 32 and then the tapered seal 30.

The tapered seal 30 forms an interference fit with an outer surface of the drainage pipe and when the end of the drainage pipe is inserted into/engaged with the inner pipe section 28 the tapered seal 30 creates a sealing connection between the end of the inner pipe section 28 and the outer surface of the drainage pipe. The sealing connection is made watertight when the threaded nut 34 is screwed on to the threaded connector 26. The action of tightening the threaded nut 34 pushes the anti-slip collar 32 into engagement with the tapered seal 30 and creates a watertight seal between the drainage pipe and the inner pipe section 28.

Referring to figure 2 and 3, the body 12 includes an internal sleeve 40, which extends down from the inlet port 16 (see figure 1).

In the illustrated example, the internal sleeve 40 is formed as an integral part of the body 12 and facilitates creation of a water seal between the base 14 and the lowest point 41 of the outlet port 20 when the trap 10 is in use.

In the illustrated example, the inlet connector assembly 50 includes a hollow sleeve 52, which is received, as a sliding fit, inside the internal sleeve 40 and is configured to move telescopically relative to the internal sleeve 40 to increase or reduce the height of the trap 10.

In figures 1 to 5 a sealing connection between the hollow sleeve 52 and the internal sleeve is provided by a suitable flexible seal (not illustrated), for example a tapered seal, a D-seal, 0-ring seal etc. and a threaded collar 19, similar to the sealing connection described above with reference to the outlet connector 23.

The sealing connection means the hollow sleeve 52 is locked against movement relative to the internal sleeve. The sealing connection is created by tightening the collar 19 onto the threaded inlet 18, which compresses the seal (not illustrated) between the threaded collar 19 and the hollow sleeve 52, thereby creating an interference/sealing connection and locking the hollow sleeve 52 against further movement. If extension or retraction of the hollow sleeve 52 is required i.e. to lengthen or shorten the trap 10, loosening the collar 19 relieves the compressive forces on the flexible seal and permits the hollow sleeve 52 to slide relative to the internal sleeve 40. The sliding movement of the hollow sleeve 52 relative to the internal sleeve 40 facilitates adjusting the height of the trap 10 (this feature is described further below).

In the illustrated example, referring to figure 1 and figure 2, the hollow sleeve 52 is inserted in the trap 10 as an assembly of components. In this regard, the inner surface of an upper portion of the hollow sleeve 52 is profiled to retain a flexible valve 60, an insert 62 and a coupling assembly 64.

The inner surface of an upper portion of the hollow sleeve 52 includes a radially extending flange 61 (see figure 2), which in the illustrated example is located about one-third down from the top edge of the hollow sleeve 52. When assembled, the insert 62 and an upper end of the flexible valve 60 rest on the flange 61.

Above the flange 61, the hollow sleeve 52 includes an internal threaded section 63, which facilitates attachment of the coupling 64 to secure the flexible valve 60 and insert 62 against the flange 61 and inside the hollow sleeve 52 (as discussed further below).

The coupling assembly 64 includes a hollow tube, which includes a midsection radially extending flange 66, a lower, externally threaded, hollow tubular section 65, an upper, smooth surface, hollow tubular section 70 and a threaded collar 74. The flange 66 is located between the lower hollow tubular section 65 and the upper hollow tubular section 70.

The flange 66 acts a stop when the threaded sections 63 and 65 are engaged.

As noted above the threaded section 65 engages with the corresponding internally threaded section 63 in the upper end of the hollow sleeve 52 and facilitates securing the flexible valve 60 and insert 62 within the hollow sleeve 52.

In the illustrated example, the upper, smooth surface, hollow tubular section 70 includes at its upper edges a radially extending flange 71, a threaded collar 74 and a seal 72. The minimum height/length of the upper, smooth surface, hollow tubular section 70 corresponds with the height/length of the threaded collar 74. It will not be appreciated from the exploded view in figure 1, but the threaded collar 74 and the hollow tubular section 70 are dimensioned to have a clearance fit and the flange 71 is dimensioned such that the collar 74 is a fixture of the coupling assembly 64.

The collar 74, via the coupling assembly 64 and the inlet connector assembly 50, facilitates connection of the trap 10 to an outlet of a sanitaryware product (not illustrated).

The collar 74 also facilitates extension of the trap 10, by providing a grip via which the inlet connector assembly 50 can be pulled upwards and outwards relative to the body 12 to increase the height of the trap 10.

As noted above, the inlet connector assembly 50 includes the hollow sleeve 52, a flexible valve 60, an insert 62 and the coupling assembly 64.

The insert 62 is operable to prevent inversion of the flexible valve 60 and the coupling assembly 64 retains the flexible valve 60 and insert 62 inside the hollow sleeve 52.

In the illustrated example, the insert 62 includes a hollow tube including an upper flange 73, a short cylindrical portion 75 extending down from the flange 73 and two substantially triangular-shaped wall sections 77 extending down from the cylindrical portion 75 In the illustrated example, the flexible valve 60 is a duckbill valve, which is typically manufactured from rubber or synthetic material, and takes its name from the shape of its flattened end, which is considered to resemble the shape of a duck's beak/bill.

In the illustrated example, the duckbill valve 60 includes a permanently open upper end 81, a transitional portion 83 and a lower, closed, end in the form of a flattened "duckbill" 85 which is closed.

The transition portion 83 tapers from a fully open configuration to a closed, flattened, configuration. The closed end of the transition portion 83 provides the upper end of the flattened, duckbill end 85. The shape of the transition portion 83 complements the shape to the insert 62 and the transition portion 83 is held open by the insert 62.

The duckbill end 85, only opens when fluid flows in the direction from the open upper end 81 to the closed end 85.

Opening the flattened end 85 allows fluid flow in one direction i.e. the direction from the sanitary ware outlet (open upper end) to the flattened "duckbill" end 85. The flattened end (also known as the "duckbill") 85 retains a natural flattened shape when there is no fluid flow and prevents backflow i.e fluid flowing in the direction from the "duckbill" to the open upper end.

In the event of backflow, the triangular wall sections 77 of the insert 62 engage with the walls of the transition portion 83 of the duckbill valve 60 such that the flexible valve/duckbill valve 60 cannot invert and thereby ensures backflow of fluid is prevented.

The closed-state of the flattened duckbill end 83 prevents odours in the event the water seal dries out or is siphoned.

It will be appreciated, when the coupling assembly 64, the hollow sleeve 52 and the flexible valve/duckbill valve 60 are assembled, the vertical position/location of the flexible valve/duckbill valve 60 is fixed relative to the hollow sleeve 52, but its position, relative to the body 12 of the trap 10, is determined by movement/placement of the hollow sleeve 52 To install the trap 10, the outlet connector 22 of the trap 10 is connected to a drainage pipe (not illustrated) which is in fluid communication with a soil stack or drainage pipe system (not illustrated).

Preferably, during this first stage of installation, the drainage pipe and the outlet connector 22 are arranged such that the axis of the inlet port 16 is aligned is with the axis of the waste outlet of the sanitaryware product (not illustrated).

To connect the inlet connector 50 to the waste outlet, the threaded collar 19 is loosened such that the hollow sleeve 52 is free to move/slide vertically relative to the internal sleeve 40 such that the upper end of the coupling assembly 64 can be engaged with a pipe section depending from the waste outlet of the sanitaryware product.

In the example illustrated in figures 1 to 7b, a watertight seal is created at the waste outlet by the interaction of the pipe sections, a flexible seal, the flange 71 and the threaded collar 74 i.e. when the threaded collar 74 is tightened relative to the seal 76 at the junction of two pipe sections a watertight seal is created.

Installation of the trap 10 is completed by tightening the collar 56 to fix the relative position of the hollow sleeve 52 and the internal sleeve 40 and ensuring a watertight seal is created at the junction of the hollow sleeve 52 and the internal seal.

Figures 4 and 5 illustrate the trap 10, as illustrated in figures 1 to 3 with the addition of an air valve 90 mounted on the stem 24 of the outlet connector 22. The air valve 90 is in fluid communication with the stem 24 The air valve 90 is operable as a one-way outlet pressure valve, which includes an inlet 92, an outlet 94 and a valve member 96. The inlet 92 and the outlet 94 are connected by a flow path. The valve member 96 rests on a support member 100. The valve member 96 includes a head 102 and a stem 104; the stem 104 slides relative to the inlet 92. The head 102 includes a seal 106 which abuts an underside of the head 102 and facilitates a sealed connection when the head 102 rests on the support member 100.

In the absence of any pressure differential, the valve member 96 rests on the support member 100, thereby preventing air flow through the air valve 90. When a pressure differential is present across the valve member 96, the valve member 96 is operable to lift away from the support member 100, thereby allowing air to flow along the flow path and ensures maintenance of the water seal within the trap.

Relieving a negative pressure differential prevents a pulling force being applied to the water seal and therefore helps prevent the water seal being sucked from the trap 10.

The air valve 90 helps to ensure the water seal is maintained and therefore helps prevent ingress of fumes and smells from the soil pipe (not illustrated).

If there is no pressure differential across the valve member 96 or there is a positive pressure differential, the valve member 96 is pressed into engagement or rests on the support member 100.

A cap 110 incorporates an internal seal 112, which ensures the air valve 90 is airtight and eases maintenance should the valve member 96 or seal 112 require to be replaced. The seal 112 and cap 110 double as a restrictor, which is operable to restrict how far the valve member 96 can move if/when it is subject to a negative pressure differential.

Locating the valve member 96 above the trap outlet 22 reduces the risk of fluid flow through the outlet 94. It will be appreciated that fluid flow through the outlet 94 would contaminate the valve member 96. The risk of contamination is further reduced by a void 114, which is defined by a gap between the valve member 96 (when resting on the support member 100) and the inside surface of the cap and seal 110, 112.

The void 114 defines a region in which air can be trapped providing a barrier between the outlet 94 and the inlet 92. The arrangement is such that if a blockage occurs in the drainage pipe system and the trap 10 fills with fluid, the fluid will be unable to displace air within the flow path of the air valve and therefore prevents contamination of the valve member 96.

In the example described above, with reference to figures 1 to 5, a conventional compression joint arrangement 19 is illustrated for tightening and creating a watertight seal at each instance of pipe-to-pipe connection.

Figures 6, 7a and 7b illustrate an alternative arrangement, which also facilitates creating a watertight seal. In the illustrated example, an alternative seal and snap-collar arrangement is used at the junction of the hollow sleeve 52 and the internal sleeve 40.

The alternative sealing arrangement between the hollow sleeve 52 and the internal sleeve 40 is provided by an arrangement of a flexible seal, for example a D-seal or an 0-ring seal 120 and a collar 122.

The seal 120 is configured to be a press-fit into a groove 124 provided on an internal upper surface of the inlet connector 50. The seal 120 is dimensioned such that at last part of the seal 120 engages with the wall of hollow sleeve 52 and is squeezed into sealing contact with both the inside surface of the groove 124 and the hollow sleeve 52 when the collar 122 is fitted.

The collar 122 is configured with a profiled internal surface 126 which contrasts with but complements with a profiled surface 127 on the outside of the inlet connector 50. The complementary, but contrasting profiled surfaces 126, 127 permits a snap-fit connection of the collar 122 to the inlet connector assembly 50.

The snap-fit connection does not require any rotation of the collar 122 to secure the connection between the hollow pipe 52 and the inlet connector 50.

The collar 122 snaps into sealing contact with the inlet connector 50 such that a watertight junction of the hollow sleeve 52 and the inlet connector 50 is created. The seal is secured by engaging an internal profiled surface of a snap collar 122 with a complementary profiled outer surface 127 on the inlet connector.

The snap collar 122 is engaged with the inlet connector 50 by a press fit; no rotation is required.

The description above has focussed on a bottle trap 10 incorporating height adjustment, where the trap (10) includes a height adjustable component incorporating a flexible shut-off/duckbill valve (60) to facilitate easier installation of a trap product 10 to a sanitaryware product. It should be appreciated that the arrangement of the components facilitating height adjustment during installation is applicable to other types of trap, for example a tubular trap, such as a P-trap or S-trap.

Various modifications and improvements can be made to the above described embodiments without departing from the scope of the invention. For example, although the trap illustrated and described is a bottle trap comprising a detachable base, it will be appreciated the trap could include a unitary body. It should be appreciated that the height adjustment aspect of the invention could be incorporated in other types of trap also, for example a tubular trap such as a P-trap or S-trap.

Claims

CLAIMS1. A plumbing trap attachable to a waste outlet of a sanitaryware product, the trap comprising: a trap body including, an inlet port, an outlet port and a first hollow sleeve extending from the inlet port into the trap body and a second hollow sleeve, wherein a first end of the second hollow sleeve is received inside the first hollow sleeve and a second end of the second hollow sleeve facilitates connection of the inlet port to the waste outlet of sanitaryware to which the trap is to be connected, wherein the second hollow sleeve is configured to slide relative the first hollow sleeve, thereby defining an adjustable neck, which moves relative to the inlet port to adjust the height of the trap; and wherein the second hollow sleeve houses an assembly of components, including a flexible shut-off valve such that the second hollow sleeve and the assembly of components, including the flexible shut-off valve all move as a unit is when the second hollow sleeve is extended or retracted relative to the first hollow sleeve and the trap body.
2. A plumbing trap as claimed in claim 1, wherein the flexible shut-off valve is a flexible duckbill valve.
3. A plumbing trap as claimed in claim 1 or 2, wherein the second hollow sleeve includes a hollow coupling, which includes a lower section, a mid-section and an upper section, wherein the lower section includes a profiled outer surface which complements an inner surface of the hollow sleeve, wherein engagement of the complementary surfaces is operable to retain the flexible shut-off valve within the second hollow sleeve.
4. A plumbing trap as claimed in claim 3, wherein the lower section and at least an internal portion of the second hollow sleeve include complementary external and internal threaded sections.
5. A plumbing trap as claimed in claim 3 or 4, wherein the mid-section includes a radially extending flange, which acts as a stop against an upper face of the second hollow sleeve, such that when the coupling and the second hollow sleeve are engaged the mid-section radially extending flange limits how far the coupling can extend into the second hollow sleeve.
6. A plumbing trap as claimed in any of claims 3, 4 or 5, wherein the upper section of the coupling is configured to connect the trap to an outlet from a sanitaryware product, wherein the upper section include a substantially smooth-walled tubular portion, a loose-fitting threaded collar and a retaining flange operable to retain the threaded collar on the coupling, wherein the threaded collar is located between the mid-section radially extending flange and the retaining flange.
7. A plumbing trap as claimed in any of claims 2 to 6, wherein the second hollow sleeve includes an insert member, which is configured to be received in an open end of the duckbill valve and includes a body shaped to prevent inversion of the duckbill valve if and when the duckbill valve is subject to backflow or associated pressures and wherein an upper edge of the insert includes a radially extending flange, which rests on a corresponding radially extending flange inside the second hollow sleeve, wherein interaction of the radially extending flanges locate and maintain the position of the duckbill valve relative to the second hollow sleeve.
8. A plumbing trap as claimed in any preceding claim, wherein the outlet port includes a threaded outlet connector, which is engageable with a threaded collar, which, when engaged provides a compression joint between the hollow sleeve 10 and the trap body.
9. A plumbing trap as claimed in any of claims 1 to 7, wherein the outlet port includes a connector comprising a textured outer surface, which is engageable with a snap-collar including a complementary textured internal surface.
10. A plumbing trap as claimed in any preceding claim, wherein the trap is a bottle trap, wherein the outlet port is arranged relative to the trap body and a base such that, in use, a water seal exists between a lowest point of the outlet port and the base.
11. A plumbing trap as claimed in claim 10, wherein axes of the inlet port and the outlet port are perpendicular to one another.
12. A plumbing trap as claimed in claim 10 or 11, wherein the base is 25 removable from the trap body.