GB2182992A - Coupling for pipes or conduits - Google Patents

Abstract

A coupling (1) for joining opposed end-to-end arranged pipe sections (2/3) comprises an annular seal (4) made of elastomeric material for location over the adjacent pipe ends of the end-to-end pipe sections to sealingly bridge the sections and a pair of substantially semi-circular clamping members (6, 7) to surround and sealingly clamp the annular seal (4). The seal (4) includes opposed pairs (8, 9) of raised lips (13, 14), the lips of each pair being spaced apart by a groove (15), while the clamping members (6, 7) include formations (10A, 11A) serving to draw the lips (13, 14) together when the clamping members (6,7) are tightened. <IMAGE>

Description

SPECIFICATION Coupling for pipes or conduits The present invention relates to couplings for pipe or conduit sections which sections are arranged in end-to-end relationship so as to form a continuous pipe-line or conduit. More specifically the present invention relates to couplings of the type having annular sealing means for location over the adjacent pipe ends of the end-to-end pipe sections to enable a sealing bridge between the sections, and annular clamping means surrounding the sealing means. Such a coupling is hereinafter referred to as a pipe coupling of the type aforesaid.

For effective operation of the above described pipeline it is important that the coupling provides a satisfactory seal between the end-to-end pipe sections. To this end, in pipe couplings of the type aforesaid it is known to provide at least one radially extending raised formation on the annular sealing means which is pressed by the clamping means to create improved circumferential sealing between the sealing means and the pipe sections. Normally a diametrically opposed pair of such raised formations is provided.

According to the present invention there is provided in or for a pipe coupling of the type aforesaid, annular sealing means having at least one radially extending raised formation, said raised formation comprising spaced portions which are adapted to be pressed by the clamping means.

Preferably a diametrically opposed pair of such raised formations are present.

Preferably an axial groove is present at the raised formations to provide said spaced portions. The groove can be of V-form but other cross-sectional forms of the grooves are possible. In a preferred embodiment said spaced portions are defined by a pair of side-by-side lips which are spaced by said axial groove.

The lips can have variety of profiles.

The clamping means preferably comprise opposed substantially semi-circular band portions providing at least one opposed flange pair enabling the band portions to be drawn together for clamping, and the arrangement is preferably such that the raised formation of the sealing means will be located between the flange pair whereby the spaced portions of the formation are pressed towards each other by the band portions during clamping. In particular the spaced portions are preferably pressed by parts of the band portions adjacent the inner ends of the flanges, and these band portion parts can be suitably shaped, being of convex form for example.In a further aspect of the present invention, a pipe coupling of the type aforesaid has annular sealing means including at least one raised formation, said raised formation having convex peripheral parts, and the annular clamping means includes corresponding concave grooves co-operating with said convex parts.

Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings wherein: Figure 1 shows an end of a pipe coupling according to a first embodiment of the present invention; Figure 2 shows a side elevation in partial section of the coupling of Fig. 1 fitted on adjacent pipe sections of a pipeline; Figure 3 shows a view of part of Fig. 1 but with the coupling in the closed sealing condition; and Figures 4 and 5 show end views (partial in Fig. 5) of pipe couplings according to further embodiments of the present invention.

Referring to Figs. 1 to 3, a pipe coupling 1 for sealingly joining end-to-end pipe sections 2, 3 (Fig. 2) of a pipe line comprises an annular sealing member in the form of an annular gasket 4 and clamping means 5 for the gasket 4 comprising substantially semi-circular band portions 6, 7. The gasket 4 is of elastic material such as rubber or suitable synthetic material and is of substantially uniform circumferential thickness. However a diametrically opposed pair of radially extending raised formations 8, 9 are present in the gasket. The band portions 6, 7 of the clamping member 5 include pairs of opposed flanges 10, 11 and the coupling arrangement is such that each raised formation 8, 9 is located between a respective flange pair 10, 11. The flange pairs 10, 11 can be drawn together by bolts 12 for creation of the clamping effect.

Each raised formation 8, 9 comprises a pair of substantially side-by-side lips 13, 14 which are spaced apart by an axial groove 15 in the gasket 4. Each lip 13, 14 has a peripheral side surface portion of convex form while the associated band portions 6, 7 have corresponding concave grooves 10A, 11A, the arrangement being such that the grooves 10A, 1 1 A abut the respective side surfaces of lips 13, 14 to locate the band portions 6, 7 on the lips 13, 14 prior to tightening and also serve to press the lips 13, 14 when the band portions 6, 7 are drawn together by bolts 12.

The groove 15 can have a V-shape crosssection as shown but other cross-sectional groove forms are possible.

The thickness T1 of the gasket at the bottom of the groove 15 is preferably slightly less than the thickness T2 of the gasket outwith the formations 8, 9. Apart from the formations 8, 9 the inner and outer surfaces of the gasket could be plain but alternatively annular slots and grooves could be provided in the gasket for possible improvement of the sealing action. Also, the cross-sectional profile of the band portions 6, 7 could include flanges and/or recesses. The clamping mem ber 5 can be made of any suitable material, for example a metal such as grey or ductile cast iron, and it would also be possible for the member 5 to be of a synthetic plastics material.

The gasket 4 is positioned by virtue of the formations 8, 9 being located between the flange pairs 10, 11 with the grooves 10A, 11A assisting location and to improve the positioning effect the lips 13, 14 could be radially extended.

In operation the gasket 4 is located around the pipe sections 2, 3 as shown in Fig. 2 and, with the band portions 6, 7 positioned around the gasket, the bolts 12 are tightened to sealingly clamp the gasket 4 between the clamping means 5 and the pipe sections 2/3.

More specifically, band portions 6, 7 draw the lips 13, 14 together from the open position in Fig. 1 to the closed position in Fig. 3, and forces are applied to the gasket 4 by the clamping means in the direction of the arrows P1, P2. Consequently the gasket 4 will be subjected to a stretching around the pipe effect and also good inward pressure will be present in the significant areas adjacent the flanges 10, 11 of the clamping means.

In the embodiment shown in Fig. 4, the gasket 4 has further portions departing from the continuous curved form to a substantially tangential form as shown at 21, 22 and this provides opposed thickened sections 23, in the gasket. The band portions 6, 7 have inner surfaces at 6A, 7A profiled complementary to gasket portions 21, 22, 23 and this arrangement provides an additional positive locating effect of the clamping member 5 on the gasket 4 and may also provide an increased pressure sealing effect. The tightening effect of the flanges 10, 11 on raised formations 8, 9 in Fig. 4 will be substantially as shown in Fig. 3. It will be appreciated that the gasket 4 could have other profile forms but nevertheless be in accordance with the present invention, and other modifications are of course possible.Whereas Fig. 1 shows double bolted flanged connections of the clamping means 5, it would be possible to have only a single bolted connection at one side of the means 5, with a pivotal coupling arrangement at the other side of the clamping means: this pivotal coupling could utilise a releasable yoke and hook system.

In the embodiment of Fig. 5, two opposed raised formations are again present (only formation 9 is shown) but in this case each formation comprises only a single lip. As can be seen, the lip 9 includes convex peripheral parts 9A,9B, while the band portions 6, 7 are provided with concave grooves 10A, 11A cooperating with these convex parts 9A, 9B to assist proper location of the band portions relative to the sealing means. The number of bolts 12 selected per side will depend on the duty of the pipeline; but normally one or two bolts 12 will be employed per side.

CLAIMS 1. A coupling for pipes or conduit sections which sections are arranged in end-to-end relationship so as to form a continuous pipeline or conduit, said coupling comprising annular sealing means for location over the adjacent pipe ends of the end-to-end pipe sections to enable a sealing bridge between the sections, and annular clamping means surrounding the sealing means, said annular sealing means having at least one radially extending raised formation, said raised formation comprising spaced portions which are adapted to be pressed by the clamping means.

2. A coupling as claimed in claim 1, wherein a diametrically opposed pair of such raised formations are present.

3. A coupling as claimed in claim 1 or 2, wherein an axial groove is present at the raised formations to provide said spaced portions.

4. A coupling as claimed in claim 3, wherein the groove is of V-form.

5. A coupling as claimed in claim 3, wherein said spaced portions are defined by a pair of side-by-side lips which are spaced by said axial groove.

6. A coupling as claimed in any one of the preceding claims, wherein the clamping means comprise opposed substantially semi-circular band portions providing at least one opposed flange pair enabling the band portions to be drawn together for clamping, and the arrangement is such that the raised formation of the sealing means will be located between the flange pair whereby the spaced portions of the formation are pressed towards each other by the band portions during clamping.

7. A coupling as claimed in any one of the preceding claims, wherein the annular sealing means has a thickened portion radially spaced from the raised formation.

8. A coupling as claimed in claim 7, wherein two diametrically opposed thickened portions are provided in the annular sealing means.

9. A coupling as claimed in claim 7 or 8, wherein the clamping means has a complementary recess or recesses to said thickened portion or portions.

10. A coupling as claimed in claim 6, wherein the raised formation has shoulder parts of convex form and the associated flange pair has inner ends of complementary concave form.

11. A coupling for pipes or conduit sections which sections are arranged in end-toend relationship so as to form a continuous pipeline or conduit, said coupling comprising annular sealing means for location over the adjacent pipe ends of the end-to-end pipe sections to enable a sealing bridge between the sections, and annular clamping means sur rounding the sealing means, annular sealing means including at least one raised formation, said raised formation having convex peripheral parts, and the annular clamping means includes corresponding concave grooves co-operating with said convex parts.

12. A coupling as claimed in any one of the preceding claims, wherein the anular sealing means is made of rubber or elastic synthetic material.

13. A pipe coupling substantially as hereinbefore described with reference to and as illustrated in Figs. 1 to 3, or Fig. 4 of the accompanying drawings.

14. A pipe coupling substantially as hereinbefore described with reference to and as illustrated in Fig. 5 of the accompanying drawings.

Claims (7)

CLAIMS New claims or amendments to claims filed on 9th April, 1986. Superseded claims 1-7. New or amended claims:

1. A coupling for pipes or conduit sections which sections are arranged in end-to-end relationship so as to form a continuous pipeline or conduit, said coupling comprising annular sealing means for location over the adjacent pipe ends of the end-to-end sections to enable a sealing bridge between the sections, and annular clamping means surrounding the sealing means, said annular sealing means having at least one radially extending raised formation, said raised formation comprising annularly spaced portions which are adapted to be pressed towards each other by the clamping means.

2. A coupling as claimed in claim 1, wherein a diametrically opposed pair of such raised formations are present.

3. A coupling as claimed in claim 1 or 2, wherein an axial groove is present at the raised formations to provide said spaced portions.

4. A coupling as claimed in claim 3, wherein the groove is of V-form.

5. A coupling as claimed in claim 3, wherein said spaced portions are defined by a pair of side-by-side lips which are spaced by said axial groove.

6. A coupling as claimed in any one of the preceding claims, wherein the clamping means comprise opposed substantially semi-circular band portions providing at least one opposed flange pair enabling the band portions to be drawn together for clamping, and the arrangement is such that the raised formation of the sealing means will be located between the flange pair whereby the spaced portions of the formation are pressed towards each other by the band portions during clamping.

7. A coupling as claimed in any one of the preceding claims, wherein the annular sealing means has a thickened portion radially spaced from the raised formation.