A device for connecting a thin-walled hose with a tubular element

Abstract: A device for connecting a thin-walled hose (4) pulled into a pipe (2) with a tubular element (6) comprises a sleeve-shaped connector element (8). At one end portion the sleeve-shaped connector element (8) is connectable with the tubular element (6) while the other end portion of the connector element is sealingly connected with the thin-walled hose (4). The sleeve-shaped connector element (8) is connected with the thin-walled hose (4) by means of two annular, concentric sealing elements (14; 16) consisting of highly elastic material between which the wall of the thin-walled hose (4) is positioned.

Description: The present invention relates to a device for connecting a thin-walled hose pulled into a pipe with a tubular element. Buried pipes consisting of metal, plastic, concrete or the like which have been subjected to damages can be restored to working order by pulling a liner provided by a relatively thin-walled hose into the pipes. Outside the damaged pipe which has been restored by means of the hose the hose has to be sealingly connected with tubular elements. The tubular elements can be constituted by pipe couplings adapted to be connected with undamaged portions of the pipe or can be constituted by end portions of undamaged sections of the pipe. According to a previously used technique the thin-walled hose has been constituted by a rubber hose. Thereby, the elasticity of the rubber material has made it relatively simple to provide the necessary, sealed connection of the hose with the tubular elements. Recently it has become common practice to manufacture the thin-walled hose from plastic material, the smaller elasticity of the hose material making it impossible to provide the necessary tightness by means of previously known connector devices. Prior art devices for providing a seal connection of a hose with tubular element are shown and described in GB-A-1 562 797, GB-A-810 990 and EP-A-0 222 051. The devices according to the first two of these publications comprise a sleeve-shaped connector element which has a first end portion and a second end portion and which is sealingly connectable at the first end portion with the tubular element and at the second end portion with the thin-walled hose by means of an annular sealing element consisting of highly elastic material. The sealing element and a part of the sleeve-shaped connector element form an annular space in which the thin-walled hose is positioned. The prior art devices include a flange portion at the second end portion of the connector element and this flange portion includes a conical surface which is engageable with the sealing element. The prior art device also comprise a locking ring which is axially pressed against the sealing elements of the device so that the sealing element is radially pressed toward the wall of the thin-walled hose, the locking ring having a conical surface which engages the sealing element in such a way that the axial pressing of the locking ring against the sealing element provides for a radial pressing of the sealing element against the wall of the thin-walled hose. It is desirable that the thin-walled hose is locked in the axial direction in relation to the sleeve-shaped connector element in order to prevent separation of the hose from the connector element. According to GB-A-1 562 797 and GB-A-810 990 this object is satisfied by providing said annular space for receiving the wall of the thin-walled hose which consists on one side by a sealing element and on the other side by a rigid surface of the connector element and pressing the hose toward the rigid surface. Thereby it is a problem that the small elasticity of a plastic hose material makes it impossible to provide the necessary thightness between the hose and the rigid surface of the sleeve-shaped connector element. According to EP-A-0 222 051 the axial locking of the hose requires a special design of the hose. Thus, the hose is provided with a reinforcement giving the surface of the hose a corrugated shape. The object of the invention is to provide a device for connecting a thin-walled hose pulled into a pipe a tubular element, the function of the device being independent of the material and the design of the hose so that a satisfactory function can be obtained also in the case of a hose material having a low elasticity, for example a plastic material, and which device provides for a correct sealing and an axial locking of the hose in relation to the sleeve-shaped connector element so that the separation of the hose from the connector element is prevented. In order to comply with this object there is provided a device of the kind described above which is characterized by the features specified in the characterising part of claim 1. Thus, the device according to the invention provides for a separation of the sealing and locking function, however, the locking as well as the sealing force is provided by one and the same element, i.e. the clamping ring which via the locking ring presses the first sealing element against the thin-walled hose and the hose into engagement with the counteracting annular surface of the sleeve-shaped connector element. In a preferred embodiment of the invention the connector element comprises a protective pipe surrounding the thin-walled hose between the end portion of the pipe into which the thin-walled hose has been pulled and the sleeve-shaped connector element. Thereby the thin-walled hose is protected against outside damages at the otherwise exposed portion between the pipe and the connector element. The invention is described in the following with reference to the accompanying drawings. Fig. 1 is an axial section of a connector device according to the invention. Fig. 2 is a detail of fig. 1 on an enlarged scale. The device shown in fig. 1 is intended for providing a tight connection between a thin-walled hose 4 pulled into a pipe 2 and a tubular element 6. The thin-walled hose 4 forms a lining in the pipe 2 having the object of restoring the pipe 2 which is presumed to be damaged to working order. The tubular element 2 can be constituted by a pipe coupling adapted to be connected with an undamaged section of the pipe to which the thin-walled pipe 4 pulled into the damaged pipe 2 has to be sealingly connected so as to restore the pipe as a whole to a tight condition. It is also possible to let the tubular element 6 constitute the end portion of the undamaged section of the pipe. The thin-walled hose consists of a relatively non-elastic plastic material for which reason the connector device according to the invention must have the capacity of providing a tight connection of a thin-walled hose with a tubular element without depending on the fact that the hose consists of a special material such as a highly elastic material. The connector device according to the invention comprises a sleeve-shaped connector element 8 having a portion 10 of a small diameter and a portion 11 of a greater diameter. The sleeve-shaped connector element 8 has at its portion 10 a shallow, outer groove 12 in which an annular strip-shaped sealing element 14 of a highly elastic material, preferably rubber, is positioned. The end portion of the thin-walled hose 4 extends around the portion 10 of the sleeve-shaped connector element 8 and engages the sealing element 14 at its inner surface. Radially outside the wall of the thin-walled hose 4 and substantially concentric with the sealing element 14 there is provided a further, annular sealing element 16 of a highly elastic material, preferably rubber. Thus, an annular portion of the wall of the thin-walled hose 4 will be positioned between the sealing elements 14 and 16. The sealing element 16 is of substantially triangular cross-sectional shape and thereby forms two outer conical surface portions 18 and 20. The conical surface portion 18 engages a conical surface 22 of an outer flange portion 24 of a portion 10 of the sleeve-shaped connector element 8. The flange portion 24 extends a distance over the outer surface of the end portion of the thin-walled hose 4 and forms together with the inwardly positioned portion of the sleeve-shaped connector element a slot 26 in which the extreme end portion of the thin-walled hose 4 is received. The conical surface portion 20 of the sealing element 16 engages a conical surface 28 of a locking ring 30 consisting of a plastic material. The locking ring 30 has an outer conical surface 32 engaged by a conical surface 34 of a clamping ring 36. The clamping ring 36 comprises a pipe socket 38 axially projecting in a direction away from the sleeve-shaped connector element 8. A protector pipe 42 consisting of a plastic material, for example polyvinyle chloride, is connected with the outer surface of the pipe socket 38 by means of a sealing ring 40. The end of the protector pipe 42 opposite from the pipe socket 38 is sealingly connected with the pipe 2 by means of a socket 44 consisting of rubber and being forced against the outer surface of the protector pipe 42 and the pipe 2 by means of hose clamps 46. The protector pipe 42 protects the thin-walled hose 4 at the exposed portion of the hose extending between the pipe 2 and the sleeve-shaped connector element 8 against rock, sand and other foreign materials. The sleeve-shaped connector element 8 is sealingly connected with the tubular element 6 by means of a sealing ring 48 having a triangular cross-section and consisting of elastic material and a clamping ring 50. The sealing ring 48 forms outer conical surfaces 52 and 54 engaging an inner conical surface 56 of the clamping ring 50 and an inner conical end surface 58 on the portion 11 of the sleeve-shaped connector element 8. The clamping rings 36 and 50 are connected with each other by means of a number of tensioning bolts, for example six bolts. When tensioning the bolts 59 by means of the nuts 60 thereof the clamping rings 36 and 50 are axially displaced towards each other, the conical surfaces 34 and 56 of the clamping rings 36 and 50 providing by their engagement with the locking ring 30 and the sealing ring 48 an axial as well as a radial compression of the locking ring 30 and the sealing ring 48, respectively. The axial displacement of the locking ring 30 provides for an engagement of the locking ring 30 with the sealing element 16 through the conical surface 28 in turn providing an axial compression of the sealing element 16 as well as a radial compression by the engagement with the conical surfaces. Thus, the sealing element 16 is pressed against the outer surface of the thin-walled hose 4 which in turn is pressed against the sealing element 14. This provides for a tight connection of the thin-walled hose 4 with the sleeve-shaped connector element 8 in spite of the fact that the thin-walled hose consists of a relatively non-yielding plastic material. The radial compression of the locking ring 30 provides that the locking ring forces the wall of the thin-walled hose 4 against an opposite surface of the portion 10 of the sleeve-shaped connector element 8 in turn providing for an axial locking of the thin-walled hose 4 in relation to the sleeve-shaped connector element 8. This action can be strengthened by providing a surface of the locking ring 30 engaging the thin-walled hose 4 with grooves or the like. The displacement of the clamping ring 50 towards the clamping ring 36 by means of the tightening of the bolts 59 provides that the sealing ring 48 is forced against the outer surface of the tubular element 6 by the cooperation between the conical surfaces 52 and 54 of the sealing ring 48 and the conical surfaces of the clamping ring 50 and the end portion of the portion 11 of the sleeve-shaped connector element 8. The connector device according to the invention provides in a simple way a reliable connection of a thin-walled hose with a tubular element. The device according to the invention is easy to mount and forms a good protection for the thin-walled hose.

Claims: A device for connecting a thin-walled hose (4) pulled into a pipe (2) with a tubular element (6), comprising a sleeve-shaped connector element (8) having a first end portion and a second end portion, the sleeve-shaped connector element being sealingly connectable at the first end portion with the tubular element (6) and being sealingly connectable at the second end portion with the thin-walled hose (4) by means of a first annular, sealing element (16) consisting of highly elastic material, the first sealing element enclosing a part of the sleeve-shaped connector element in substantially concentric relationship such that there is provided between the first sealing element and said part of the sleeve-shaped connector element an annular space in which the thin-walled hose (4) is positioned, the connector element (8) including at its second end portion a flange portion (24) having a conical surface which is engageable with the first sealing element, the device further comprising a locking ring (30) which is axially pressed against the first sealing element (16) so that the sealing element engages the conical surface of the flange portion to provide a radial pressing of the first sealing element toward the wall of the thin-walled hose which is thereby pressed toward said part of the sleeve-shaped connector element, the locking ring having a conical surface engaging the first sealing element in a manner such that the axial pressing of the locking ring against the first sealing element provides for the radial pressing of the first sealing element against the wall of the thin-walled hose, characterized in that it comprises a second sealing element (14) consisting of highly elastic material positioned on the part of the sleeve-shaped connector element which provides together with the first sealing element (16) the annular space so that a portion of the thin-walled hose (4) is positioned between the two seals, and a clamping ring (36) for pressing the locking ring (30) against the wall of the thin-walled hose while being counteracted by an annualar surface of the sleeve-shaped connector element (8) for providing a clamping force and thereby an axial locking of the thin-walled hose in relation to the sleeve-shaped connector element (8). A device as claimed in claim 1, characterized by a sealing ring (48) for sealing the sleeve-shaped connector element (8) in relation to the tubular element (6) and by a clamping ring (50) for pressing said sealing ring against the connector element and the tubular element. A device as claimed in claim 2, characterized in that the clamping rings (36; 50) are connected with each other by means of clamping elements (59), for example tensioning bolts, the clamping rings being adapted to be pressed against the locking ring (30) and the sealing ring (48) which is adapted to seal the sleeve-shaped connector element in relation to the tubular element, said pressing being provided by displacement of the clamping rings towards each other. A device as claimed in any of claims 1 - 3, characterized in that the clamping ring which is positioned at the end of the connector element positioned adjacent the thin-walled hose is provided with a pipe socket (38) directed from the connector element and constituting a connector socket for a protector pipe (42) surrounding the thin-walled hose between the end portion of the pipe, into which the thin-walled hose has been pulled and the sleeve-shaped connector element. A device as claimed in claim 4, characterized in that the protector pipe (42) is connected with the pipe into which the thin-walled hose is pulled by means of a sleeve (44) consisting of elastic material, preferably rubber, which is pressed against the outer surfaces of the protector pipe and the pipe, respectively, by means of hose clamps (46). A device as claimed in any of the preceding claims, characterized in that the second annular sealing element (14) is positioned in a groove (12) in the sleeve-shaped connector element (8). A device as claimed in claim 6, characterized in that said second sealing element (14) positioned in the groove in the sleeve-shaped connector element is strip-shaped and has a section the thickness of which is in substantial agreement with the depth of the groove (12) in the compressed condition of the sealing element.

Inventors: VON FEILITZEN JOHAN, VON FEILITZEN, JOHAN
Applicants: FORSHEDA AB
Application year: 1991
Main classification: F16L25
IPC codes: F16L58, F16L21