GB2264338A - Hose connector and nipple with sealing sleeve - Google Patents

Abstract

A hose connector for use in a hose termination comprises a cylindrical nipple (1) having a serrated portion (2) towards one end, the hose connecting end, serving as a gripping surface for a hose (4, 5, 6), the hose being gripped on the nipple (1) by a retaining sleeve (3). The nipple (1) includes extensive plain cylindrical surface (11) outwardly of the serrated portion (2) at said hose connecting end, and this plain surface (11) carries a sealing sleeve (12) of compressible material e.g. rubber (vulcanizate), the hose being pressed sealingly against the sealing sleeve (12) by the retainer sleeve (3). The sealing sleeve (12) prevents undesirable fluid leakage from the hose where there is hose puncturing at the serrated portion (2) by precluding fluid flow to said serrated portion (2). The connector is particularly useful with a hard wall hose having wire reinforcement (8). <IMAGE>

Description

Hose Connector The present invention relates to a hose connector for use at the terminations of hose assemblies especially of heavy duty rig supply hoses. More especially the invention relates to a hose connector of the type including a connector member or nipple to receive the hose end, and a retainer member co-operating with the connector member for retainment of the hose by the connector, a surface of the connector member including a gripping portion for example carrying serrations to ensure that the hose is tightly gripped on the connector member.

Heavy duty supply hoses for use in oil and gas drilling and production rigs are used inter alia to transfer various commodities from rig supply vessels to the rig platform, and the hose strings are made up from a number of hose assemblies joined together by hose terminations comprising hose connectors. The hose assemblies therefore may hang vertically from the rig platform and it is necessary that the hose end is tightly gripped by the connector in the termination to provide an effective seal and to avoid the risk of the hose being pulled away from the termination, especially during the passage of commodities by the hose. There are various methods of fitting connector terminations to hoses including clamping, banding, wiring in, or the utilisation of external swaging or internal swaging.

All these methods incorporate a connector member or nipple inserted into the hose, in the case of swaging the hose being clamped between the nipple and a retainer member in the form of a sleeve. Consequently in all these methods the hose wall is compressed or crushed onto the nipple surface, especially on the gripping portion at a tail end of the nipple, to captivate the termination onto the hose and to provide a fluid pressure seal during operation (i.e. commodity passage).

There has been the disadvantage in previous terminations that pressure fluid has been able to escape into the hose via a weakness in the hose caused by the compression effect and this has resulted in failures in the hose assemblies. In particular, the hose layer adjacent the gripping portion has been so weakened or even punctured due to the compression on the hose that fluid, especially under pressure, passing in the hose has managed to escape via this layer unto the adjacent textile layer and cause bursting of the hose.

It is an object of the present invention to obviate or mitigate this disadvantage.

According to the present invention a hose connector for use in a hose termination comprises a substantially incompressible connector member or nipple to receive an end of a hose, the connector member including a gripping portion whereat the hose is secured to the connector; and a sealing portion including a sealing member, to preclude escape of fluid to said gripping portion. In particular, the sealing portion of the connector member preferably includes a sleeve of compressible material e.g. rubber (vulcanizate).

Thus when the termination is assembled and fitted into a hose assembly the compressible sleeve creates an effective pressure sealing plug acting against the pressurised contents of the hose assembly, to prevent fluid leakage into the body of the termination, and specifically to the gripping portion of the connector.

The present invention is also a connector nipple for a hose termination, said nipple having an end adapted to receive a sealing device. Preferably said end is adapted to receive a compressible sleeve, and the end can comprise a substantially plain elongate annular (e.g. cylindrical) surface; the surface therefore may lie adjacent the serrated hose gripping portion of the connector nipple and the surface preferably has a length at least twice the serration pitch length.

An embodiment of the present invention will now be described by way of example with reference to the accompanying drawings wherein: Fig. 1 - shows in cross-section elevation, a first prior art connector termination for a hose assembly; Fig. 2 - shows a similar view for a second prior art arrangement; Fig. 3 - shows a side view, in partial section, of a connector nipple for a hose termination, in accordance with the present invention; Fig. 4 - shows a sectional end detail of the nipple of Fig. 3 used with a softwall hose; and Fig. 5 - shows a similar view but for the nipple used with a hardwall hose.

The prior art hose termination shown in Fig. 1 includes a connector nipple 1 having an end portion 2 of serrated form to define a gripping portion (2), for a hose H, the hose H being clamped between the nipple 1 and an outer retainer sleeve 3 at the portion 2. In this example, this clamping is achieved by an internal swaging operation involving the presentation of a suitable swaging tool into the internal bore of the nipple 1, the nipple 1 and sleeve 3 being of noncompressible material, preferably metal. By virtue of the swaging, the hose wall is compressed (crushed) between the retaining sleeve 3 and the serrated gripping portion 2 of the nipple 1.Hoses H of heavy duty rig supply type are of multi-layer construction comprising, for the softwall hose shown in Fig. 1, an inner relatively thin liner 4 of rubber (vulcanizate), an intermediate layer 5 of textile yarn and an outer cover 6 of rubber or the like. The compression can cause the crests of the serrations 2A to puncture the liner 3, even after a relatively short in-use period, and in the termination of Fig. 1 fluid passing under pressure in the hose H can leak through the nipple nose 1A and into layer 5 of the hose at the portion 2 via the punctured liner 4. Alternatively the liner 4 may be so reduced in thickness at the portion 2 by the serrations, that fluid under pressure can burst its way through the liner 4.

Fluid can now pass back along the hose wall, especially by virtue of capillary action in the textile layer 5, and away from the compressed area at portion 2. The leaked fluid under pressure can now burst the hose wall to create a hose failure. Fig. 2 shows an improved form of prior art connector nipple 1 in which a front portion 7 of the nipple adjacent the gripping portion 2 constitutes a plug, and this plug has a certain ability to prevent the pressurised fluid content of the hose H, in operation, leaking into the textile yarn layer 5 of a softwall hose. However, in hardwall hoses (as shown in Fig. 2) where there is a high tensile wire reinforcement 8 in the layer 5, this hard walled plug (metal) arrangement leads to puncturing of the hose liner 5 between the plug end 7 of the nipple and the high tensile wires 8 in the hose wall, enabling leakage of high pressure fluid to occur.Consequently bursting of the hose by the leaked high pressure fluid is again possible.

The nipple 10 in accordance with the present invention shown in Fig. 3 includes an elongate surface 11, preferably cylindrical, at the nipple nose to provide a high pressure sealing device, and to this end the surface 11 supports a sealing sleeve 12 of compressible (resilient) material for example of rubber (vulcanizate) material. The surface 11 can have a length L at least twice the pitch P of the serrations 2A, an the arrangement is such that, with the sleeve 12 of an appropriate material, thickness and width, an efficient pressure plug is created at the surface 11 so that even if the liner 4 is punctured at the gripping portion 2 the plug prevents the pressurised fluid contents of the hose from passing to the portion 2 for escape through the puncture. In particular, the nature of the plug at portion 11 avoids the risk of liner punctures at this portion 11 when the termination including nipple 11 is used with a hardwall hose as shown in Fig. 5. From a comparison of Fig. 5 with Fig.

2 it will be seen that the resilient lined plug at portion 11 of Fig. 5 has a considerable less tendency to cause puncturing of the hose liner 4, compared to the action of the hard walled (metal) plug of portion 7 on the liner 4 in Fig. 2. Of course the connector of the present invention is also effective when used with softwall hoses as shown in Fig. 4, and indeed the pressure plug at portion 11 constitutes an even more effective softwall plug than the plug (7) of Fig. 2 so that the risk of failure in a softwall hose is even further reduced with the present invention,

Claims (14)

CLAIMS.

1. A hose connector for use in a hose termination comprising a substantially incompressible connector member or nipple to receive an end of a hose, the connector member including a gripping portion whereat the hose is secured to the connector; and a sealing portion including a sealing member, to preclude escape of fluid to said gripping portion.

2. A hose connector as claimed in claim 1, wherein the sealing portion of the connector member includes a sleeve of compressible material e.g. rubber (vulcanizate).

3. A hose connector as claimed in claim 1 or 2, wherein the gripping portion of the connector member is of serrated form, and the connector member includes a surface portion outwardly of said serrated gripper portion adapted to receive a sealing member.

4. A hose connector as claimed in claim 3, wherein said surface portion is of cylindrical form, and a sleeve of sealing material is located on said cylindrical surface portion.

5. A hose connector as claimed in claim 3 or 4, wherein the said surface portion has a length of the lead twice the pitch of said serrations.

6. A hose connector as claimed in claim 5, wherein said length is at least three times said pitch length.

7. A connector nipple for a hose termination, said nipple having an end adapted to receive a sealing device.

8. A connector nipple as claimed in claim 7, wherein said end is adapted to receive a compressible sleeve.

9. A connector nipple as claimed in claim 8, wherein the end comprises a substantially plain elongate annular (e.g.

cylindrical) surface.

10. A connector nipple as claimed in claim 9, wherein the nipple includes a serrated hose gripping portion and said plan elongate annular end is located adjacent said serrated gripping portion.

11. A connector nipple as claimed in caim 10 wherein said annular end has a length at least twice the pitch of the serrations.

12. A connector nipple as claimed in claim 11, wherein said length is at least three times said pitch.

13. A hose connector substantially as hereinbefore described with reference to and as illustrated in Figs. 3 to 5 of the accompanying drawings.

14. A connector nipple for use in a hose connector substantially as hereinbefore described with reference to and as illustrated in Figs. 3 to 5.