WO2005068889A2

WO2005068889A2 - Pipe coupling

Info

Publication number: WO2005068889A2
Application number: PCT/ZA2004/000150
Authority: WO
Inventors: Ian Cartledge
Original assignee: Ian Cartledge
Priority date: 2003-12-23
Filing date: 2004-12-03
Publication date: 2005-07-28
Also published as: WO2005068889A3

Abstract

A pipe coupling (1) is provided comprising a clamp (2) adapted to operatively encircle collinear pipe ends (4) to be connected utilising the coupling. The clamp is of generally tubular shape and is composed of a plurality circumferentially extending parts (6) each of which has an inner periphery shaped for cooperation with a part of the circumference of said pipe ends so that all of said parts together substantially encircle such pipe ends. Each of said parts has a generally continuous or discontinuous inwardly directed locating formation (7) towards its free end having an inner generally part circular locating surface (8) adapted to cooperate with the outer surface of a pipe (5) adjacent an associated pipe end and a generally continuous inwardly directed sealing formation (10) spaced axially inwards of the adjacent locating formation and having a generally part circular sealing surface (11) adapted to cooperate with a deformable sealing sleeve (3) operatively encircling pipe ends being connected.

Description

PIPE COUPLING

FIELD OF THE INVENTION

This invention relates to a pipe coupling for connecting the ends of two lengths of generally rigid pipe in end to end relationship. Such pipes may be metal pipes, ceramic pipes, cementitious pipes and numerous other forms of rigid pipes as well as pipes that may not be entirely rigid but exhibit physical characteristics that are appropriate for enabling a pipe coupling provided by the invention to be employed therewith. For purposes of simplicity such pipes will be referred to herein as rigid pipes.

BACKGROUND TO THE INVENTION

The connecting of collinear lengths of rigid pipe together is commonly achieved by welding to each free end of each length of pipe, a pipe flange that is then fastened to an adjacent pipe flange of an end of a collinear length of pipe. Fastening of the flanges together can be achieved in numerous different ways, most commonly, by means of bolts passing through perforations in the flanges but also quite commonly by means of clamping arrangements that urge the flanges towards each other in the axial direction of the pipe.

A number of different arrangements of pipe couplings have been proposed for connecting adjacent plain ends of coaxial pipes, but, as far as applicant is aware, there is generally associated these pipe couplings either difficulties in introducing the pipe ends into what is typically an elastomeric seal forming part of the pipe coupling, or difficulties are experienced in manipulating the pipes with respect each other and the pipe coupling. These difficulties are overcome as applied to flexible pipes made of deformable material by the expedient described in my published international (PCT) patent application WO0077435 entitled "FLEXIBLE TUBE CLAMP". That expedient provides an inner rigid tubular support socket onto which the free ends of the flexible pipes are introduced and the flexible pipe material is clamped to the inner support socket by a multi part clamp that encircles the joint between the two pipe ends. Whilst this expedient opperates effectively on flexible tubes, it is inappropriate to the coupling of rigid pipe ends.

OBJECT OF THE INVENTION

It is, accordingly, an object of this invention to provide a pipe coupling that can easily and effectively be utilised to connect the ends of two collinear lengths of rigid pipe.

SUMMARY OF THE INVENTION

In accordance with this invention there is provided a pipe coupling comprising a clamp adapted to operatively encircle collinear pipe ends to be connected utilising the coupling and wherein the clamp is of generally tubular shape and is composed of a plurality of circumferentially extending parts each of which has an inner periphery shaped for cooperation with a part of the circumference of said pipe ends so that all of said parts together substantially encircle such pipe ends, in use, and means for urging the parts radially inwards to effect clamping thereof onto said pipe ends, the pipe coupling being characterised in that each of said parts has a generally continuous or discontinuous inwardly directed locating formation towards its free end having an inner generally part circular locating surface adapted to cooperate with the outer surface of a pipe adjacent an associated pipe end, and a generally continuous inwardly directed sealing formation spaced axially inwards of the adjacent locating formation and having a generally part circular sealing surface adapted to cooperate with a deformable sealing layer operatively encircling pipe ends being connected.

Further features of the invention provide for the locating formation to be the inner edge of an inwardly directed ridge or flange formed integral with the clamp part; for the sealing formation to be the inner edge of an inwardly directed ridge or flange formed integral with the clamp part at a position axially inwards of the nearest locating formation; for the clamp parts to have an inner surface of generally right circular part cylindrical shape between the locating and sealing formations and between adjacent sealing formations; for the clamp parts to have an outer surface of generally right circular part cylindrical shape with circumferentially extending reinforcing flanges; for the means for urging the parts radially inwards to effect clamping to be screw threaded fasteners cooperating with radially extending clamping flanges extending along the length of each clamp part at the circumferential ends thereof; for the clamp to be composed of two, three, or four circumferentially extending clamp parts; for the sealing layer to be in the form of a sealing sleeve; and for the coupling to be supplied with a sealing sleeve of deformable material therein.

In order that the invention may be more fully understood one embodiment thereof will now be described with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:-

Figure 1 is a perspective view of one embodiment of clamp of a coupling of the present invention; and, Figure 2 is a longitudinal sectional elevation taken through a joint between two collinear pipe ends wherein a clamp as illustrated in Figure 1 is employed.

DETAILED DESCRIPTION WITH REFERENCE TO THE DRAWINGS

In the embodiment of the invention illustrated in the drawings a pipe coupling, generally indicated by numeral (1) in Figure 2, is composed of a pipe clamp, generally indicated by numeral (2) in Figure 1, and a deformable sealing sleeve (3) that extends over the contiguous ends (4) of collinear pipes (5).

The pipe clamp is, in this embodiment of the invention, composed of four circumferentially extending parts (6) that together form a generally tubular shape that operatively receives the ends of the pipes being connected. Each part thus conforms substantially, in end view, to a quarter of a circle and has an inwardly directed locating flange (7) at each end thereof with an inner locating edge (8) that is part circular in shape and configured to cooperate the outer surface (9) of a cooperant pipe. The four inwardly directed locating flanges of the four clamp parts thus form a generally continuous circular locating surface about the outer surface of a pipe, in use.

Spaced inwardly from each end of each clamp part is an inwardly directed sealing flange (10) that has a part circular inner sealing edge (11) that likewise, together with those of the other clamp parts, form a generally continuous circular sealing surface about the outer surface of the deformable sealing sleeve (3). Clearly the diameter of this circular sealing surface is somewhat greater than the diameter of the circular locating surface in order to accommodate a thickness of sealing material between the sealing surface and the outer surface of the pipe.

The general construction of each clamp part is such that it has a generally right circular cylindrical inner surface (12) from which the locating flanges and that sealing flanges extending inwards, and a series of longitudinally spaced circumferentially extending reinforcing flanges (13) on the outer surface. The reinforcing flanges terminate at radially extending clamping flanges (14) that are perforated as indicated by numeral (15) to receive bolts (16) for clamping the parts together.

In use, in order to connect the two ends of collinear pipes, the sealing sleeve is firstly introduced onto one pipe and the other pipe can then be located in its coaxial position. The sleeve can then be slid to a position in which it extends over the two pipe ends and the clamp parts can be installed over the sleeve and tightened to clamp the coupling firmly in position. During this procedure the locating flanges engage the outer surfaces of the pipes, and simultaneously the deformable sealing sleeve becomes deformed radially inwards so as to sealingly engage the outer surfaces of the pipes and form a completely fluid tight seal.

It will be understood that the sealing sleeve can be made of numerous different materials that lend themselves to deformation radially inwards into a sealing condition and suitable materials include suitable plastics materials, mastic materials, as well as elastomeric materials. It is also within the scope of this invention that the outer surfaces of the pipes can be coated with a suitable sealing material that cooperates with the sealing sleeve.

From a manufacturing point of view, only a single clamp component need be manufactured as all of the clamp components are identical. Also, the sealing sleeve can be manufactured as an extrusion and simply cut to length, as may be required.

In the invention therefore provides a simple yet highly effective pipe coupling that obviates the necessity of welding or otherwise providing any flanges on the ends of, for example, metal pipes. It will be understood that numerous variations may be made to the embodiment of the invention described above without departing from the scope hereof. In particular the number of parts of the clamp can be varied widely and, accordingly, two or three parts may equally well be used, three be preferred as an alternative to four.

Claims

CLAIMS:

1. A pipe coupling (1) comprising a clamp (2) adapted to operatively encircle collinear pipe ends (4) to be connected utilising the coupling and wherein the clamp is of generally tubular shape and is composed of a plurality of circumferentially extending parts (6) each of which has an inner periphery shaped for cooperation with a part of the circumference of said pipe ends so that all of said parts together substantially encircle such pipe ends, in use, and means (14, 16) for urging the parts radially inwards to effect clamping thereof onto said pipe ends, the pipe coupling being characterised in that each of said parts has a generally continuous or discontinuous inwardly directed locating formation (7) towards its free end having an inner generally part circular locating surface (8) adapted to cooperate with the outer surface of a pipe (5) adjacent an associated pipe end, and a generally continuous inwardly directed sealing formation (10) spaced axially inwards of the adjacent locating formation and having a generally part circular sealing surface (11) adapted to cooperate with a deformable sealing layer (3) operatively encircling pipe ends being connected.

2. A pipe coupling as claimed in claim 1 in which the locating formation is an inner edge (8) of an inwardly directed ridge or flange (7) formed integral with the clamp part.

3. A pipe coupling as claimed in either one of claims 1 or 2 in which the sealing formation is the inner edge (11) of an inwardly directed ridge or flange (10) formed integral with the clamp part at a position axially inwards of the nearest locating formation.

4. A pipe coupling as claimed in any one of the preceding claims in which the clamp parts have an inner surface of generally right circular part cylindrical shape between the locating and sealing formations and between adjacent sealing formations.

5. A pipe coupling as claimed in any one of the preceding claims in which the clamp parts have an outer surface of generally right circular part cylindrical shape with circumferentially extending reinforcing flanges (13).

6. A pipe coupling as claimed in any one of the preceding claims in which the means for urging the parts radially inwards to effect clamping are screw threaded fasteners (16) cooperating with radially extending clamping flanges (14) extending along the length of each clamp part at the circumferential ends thereof.

7. A pipe coupling as claimed in any one of the preceding claims in which the clamp is composed of two, three, or four circumferentially extending clamp parts.

8. A pipe coupling as claimed in any one of the preceding claims in which the sealing layer is in the form of a sealing sleeve (3)

9. A pipe coupling as claimed in any one of the preceding claims in which the coupling is supplied with a sealing sleeve of deformable material therein.