MXPA97001625A

MXPA97001625A - Coupling device for tubes with different diameters

Info

Publication number: MXPA97001625A
Application number: MXPA/A/1997/001625A
Authority: MX
Inventors: Nijsen Dries
Original assignee: Georg Fischer Waga Nv
Priority date: 1996-03-04
Filing date: 1997-03-03
Publication date: 1998-04-01

Abstract

The present invention relates to a coupling device for a tube comprising a sleeve portion having at least one insertion end for the tube and an obturation or sealed piece which is suitable for providing obturation around the tube inserted in the portion of the tube. The sealed part comprises a plurality of essentially wedge-shaped elements forming a ring around the tube, and whose organ is further provided with a pressing means for pressing said elements against the tube, whereby the elements along the the outer circumference of said ring has a greater thickness than along said inner circumference, characterized in that the elements slidably contact each other to form a substantially closed ring, and have a length that is greater than the spacer along the circumference external and internal ring to cause the elements to rotate and maintain their interrelations ions slidably butt when the pressure medium works to adjust the diameter of the ring to your

Description

COUPLING DEVICE FOR DIFFERENT DIAMETER PIPES The present invention relates to a coupling device for a tube comprising a sleeve part having at least one end part inserted in the tube and a suitable plug to provide a seal around the inserted tube inside the cuff part. Such coupling device is known from European Patent No. 0 418 961. In this known coupling device, a sealing piece is used consisting of an inner ring surrounded by a rubber sealing gasket, whose inner ring is supported by supporting surfaces of the sleeve portion in order to push this sealing ring against the outside of the tube. This known coupling device is capable of accepting and coupling tubes having different diameters so that a seal is provided for liquids, gases and solids, and tubes of different diameters and, if necessary, different materials can be coupled together. This can be achieved with the known sealing ring because it can be compressed in the circumferential direction and, to a certain degree, around the tube so that it can be adapted to the different tube diameters, while in transverse section the sealing ring maintains its relatively acceptable shape .

This known device still presents a number of problems. First, when using the known coupling device with smaller tube diameters, the seal ring holder can pose a problem because the sealing ring has to deform to such an extent that the sealing effect is no longer guaranteed. Another problem with the known coupling device is that it does not have sufficient tensile strength. These coupling devices are usually applied to couple underground tubes, for example under a road. Due to the movement of the ground, possibly caused by the traffic, such coupling is not firmly fitted and, due to the displacement of sand, etc., the coupling of the known coupling devices can be released so that leakage occurs. Now the invention aims to offer a solution to these problems. For this purpose, the coupling device of the invention is characterized in that the sealing part comprises a plurality of elements in sliding contact forming part of a substantially closed ring, and whose elements increase in thickness radially, and whose part is also provided with means of pressure to compress the elements against the tube inserted inside the coupling device. The coupling device according to the invention provides seals that can be used both inside and outside the tube. The pressure means serve to compress the elements against the tube from the outside inwards and from the inside outwards, respectively, to fit the tube. In this way, the ring formed by the elements can, with respect to the diameter, easily adapt to the tube to be sealed, while also easily accommodating irregularities on the surface of the tube. The elements could be arched but it is preferable that the elements are substantially cuneiform. The side faces that form the wedge of the cuneiform elements can, for example, form an angle of 6o, in which case sixty cuneiform elements are sufficient to form the closed ring. On the one hand, the sealing ring may also consist of elements shaped differently, but other numbers of such elements are also possible. For example, if the angle between the side faces forming the wedge is 5 °, seventy-two elements are necessary to form the closed ring. The more elements that are used, the finer the distribution will be and the narrower will be the adjustment on the tube to be sealed. The invention is based on the surprising understanding that by moving the elements in contact, the elements rotate so that the diameter adjustment takes place by means of the elements that form the closed ring. When applied to the outside of the tube, the desired diameter is adjusted by starting with a larger diameter and then compressing the elements against the tube by the pressure means, whereby the adjustment to the desired diameter of the closed ring automatically occurs. In order to obtain the necessary firmness of the seal, it is desirable that each element be provided with a notch on a first side and of a projection on a second side opposite the first side of the element, which notch and protrusion are suitable for interacting with a protrusion and a corresponding notch, respectively, of a contiguous element. This fixes the sealing piece to prevent mutual twisting of the elements. The sealing effect of the coupling device according to the invention is assisted by the fact that the sealing part comprises a rubber ring, at least a portion of which is located between the tube and the elements. It is conceivable to make the rubber ring completely surround the set of elements, but this is not necessary to achieve the object of the invention. In an alternate embodiment, the side of the elements that make contact with the tube are partially made of rubber. The tension discharge effect of the coupling device according to the invention is achieved in particular if at least some of the elements are, on the one hand, provided with a rough surface which makes contact with the tube. For this there are also different possible options. For example, one or more elements may be provided with a toothed gripping element. This unloads the traction very effectively, however, it is also possible to provide the rough surface by sticking grains of sand onto the particular surface of the elements. In another embodiment, the elements are provided with a gripping ring extending at least over a part of the circumference of the tube. In order to withstand the tensile discharge effect, at least some of the elements which are evenly distributed over the circumference of the tube may be made of a material harder than that of the tube, such as metal, and preferably stainless steel. To optimize the narrow fit of the elements that make contact with the tube in the circumferential direction, independently of the diameter discrepancies of the tube, the surface of the elements that make contact with the tube is arched in the circumferential direction of the tube. Several systems could serve as pressure media for cuneiform elements. In a first embodiment of the coupling means according to the invention, the pressure means for the elements are provided with a hydraulic annular chamber that contains the elements that serve this chamber as a displaceable wall; The hydraulic chamber is also provided with a sealing connector opening for supplying a fluid to produce the hydraulic pressure in the chamber. However, in an alternate embodiment, the coupling device is made such that the sleeve portion at least around the tube is provided with a supporting surface for the elements, the diameter of the supporting surface in the longitudinal direction of the tube. decreases and increases, respectively, by means of which the support surface, by interaction with the elements, forms the pressure means for compressing the elements against the tube. The invention also materializes in a separate sealing piece and a separate cuneiform element, such as may be applied in the coupling device according to the invention. The invention will now be further clarified with reference to the drawings of a non-limiting embodiment, in which: Figure 1A shows a longitudinal section through a part of a first embodiment of the coupling device according to the invention, - the Figure IB shows a longitudinal section through a part of a second embodiment according to the invention; Figure 2 shows a longitudinal section through a third embodiment of a coupling device according to the invention; Figure 3A shows a side view of the arcuate elements forming a closed ring according to the invention; and Figure 3B is a side view of the cuneiform elements forming a closed ring according to the invention. Parts that are the same have the same reference numbers in the figures. Figures 1A, IB and 2 show a first, second and third embodiment of the coupling device according to the invention, comprising a sleeve portion 1 having an end 2 of part inserted into the tube 10 and a sealing piece 3 which is suitable to provide a seal around the tube 10 inserted into the sleeve portion l. According to the invention, the sealing part 3 comprises a plurality of uniform arched or cuneiform elements 4; see also Figures 3A and 3B showing these two modalities of the assembled elements in a side view. As can be seen in Figures 3A and 3B, the arcuate, cuneiform elements 4, respectively, jointly form a closed ring. Figures 3A and 3B also show part of the ring after the inter-rotation of the elements 4 which reduces the diameter of the ring. The embodiment of Figures 1A, IB and 2 further provides pressing means 5, 6, 7, 8, 9, 11 for compressing the various elements 4 against the tube 10. Each of the arcuate, cuneiform elements, respectively, is provided. of a notch (not shown) on the first side and of a projection (also not shown) on the second side of the element 4 located opposite the first side, which serve for its interaction with a corresponding projection and notch, respectively, in a contiguous element 4. Figures 1A and IB show that the sealing piece 3 comprises a rubber ring 12, at least a portion of which is located between the tube 10 and the arcuate, cuneiform elements 4, respectively. An alternative embodiment (not shown) could be that the side of the elements 4, which make contact with the tube 10 and a support surface 9, is itself made partially of rubber. As shown in Figures 1A and 2, at least some of the cuneiform elements 4 are partially provided with a rough surface 13 which makes contact with the tube 10. Figure IB shows the embodiment lacking the rough surface. The rough surface can be made in different ways. For example, it is plausible that a recess of the ring, formed by the cuneiform arcuate elements 4, respectively, is provided with a perforated band having a rough surface, or that the surface of the elements 4 facing the tube 10 is provided with a rough layer, for example sand. The roughened surface 13 further increases the tensile discharge effect for the coupling device while the aforementioned rubber ring 12 increases the sealing effect of the coupling device. An alternative aid for the pull-off effect consists of the uniform distribution, along the circumference of the tube 10, of arcuate, cuneiform elements 4, respectively, made of metal, preferably stainless steel. This is not shown in the drawing. Preferably, the surface 14 (see FIGS. 3A and 3B) of the arcuate or cuneiform elements 4, which is intended to make contact with the tube 10, is a surface that is arcuate in the circumferential direction of the tube and towards the tube. This produces a limited open space between the different elements 4 and the tube surface 10 with which they make contact. In this way, the arcuate or cuneiform elements 4 provide the best possible closed front in relation to the wall of the tube 10, which is important for the sealing effect of the seal 3. Figures 1A and IB also show a first embodiment of the pressure means 8, 9, 11 for the cuneiform elements 4. The embodiment of Figures 1A and IB provides two support surfaces 9 and 11 which, under the influence of the coupling 8, can move towards each other, so that said surfaces 9 and 11 of support exert a force on the elements 4 directed towards the tube 10.

Figure 2 shows a further embodiment in which the side of the arcuate or cuneiform elements 4, which is oriented opposite the tube 10, is provided with a hydraulic chamber 7 annularly extended around the tube 10. The hydraulic chamber 7 is provided of a pluggable connector opening 5 for supplying a fluid to produce a hydraulic pressure within this chamber. This pressure acts on the elements 4 by means of a separating wall 6 which serves to prevent the leakage of the fluid. One of the advantages of the coupling device according to the invention is that, within certain limits determined by the shape of the elements 4, the tube 10 can be rotated axially inside the coupling device without reducing the sealing effect of the coupling or the traction discharge . Another advantage is that the coupling device can also be applied with a non-round tube since the cuneiform elements can be simply aligned accordingly, whereby, in the case of transitions at an acute angle, intermediate pieces can be used for bridging such angled transitions. It can also be mentioned that the coupling device according to the invention is very tolerant of repair work, particularly in the case of continuous pipes, because the ring of connecting elements 4 can be disassembled and reassembled at any desired point. Finally, it should be mentioned that the modalities treated only include examples and that several alternate modalities are possible without departing from the idea of the invention as specified in the following claims.

Claims

CLAIMS 1. A coupling device for a tube comprising a sleeve portion having at least one end of a portion inserted into the tube and a sealing part that is suitable for providing a seal around the tube inserted within the sleeve portion, characterized wherein the sealing part comprises a plurality of elements in sliding contact forming part of a substantially closed ring, and whose elements increase radially in thickness and whose part is further provided with pressure means for compressing the elements against the tube. The coupling device according to claim 1, characterized in that the elements are substantially cuneiform. The coupling device according to claim 1 or 2, characterized in that each element is provided with a notch on a first side and of a protrusion on a second side of the element opposite the first side, whose notch and protrusion are suitable for interaction with a corresponding projection and notch, respectively, of a contiguous element. The coupling device according to claims 1 to 3, characterized in that the sealing part comprises a rubber ring, at least a portion of which is located between the tube and the elements. 5. The coupling device according to claims 1-3, characterized in that the sides of the elements making contact with the tube are partially made of rubber. 6. The coupling device according to claims 1-5, characterized in that at least some elements are partially provided with a rough surface that makes contact with the tube. The coupling device according to claim 6, characterized in that the rough surface is a toothed gripping element incorporated in the element. The coupling device according to claim 6, characterized in that the elements are provided with a gripping ring extended at least over part of the circumference of the tube. The coupling device according to claims 1 to 8, characterized in that at least one or some of the elements that are distributed uniformly on the circumference of the tube, are made of a harder material than that of the tube, such as metal, and stainless steel, preferably. The coupling device according to any of the preceding claims, characterized in that the surface of the element, which makes contact with the tube in a circumferential direction, is an arcuate surface in the circumferential direction of, and towards, the tube. The coupling device according to claims 1 to 10, characterized in that the pressure means for the elements comprise a hydraulic annular chamber containing the elements constituting a displaceable wall of this chamber, and because the hydraulic chamber is provided with a pluggable connector opening for supplying a fluid to produce the hydraulic pressure within the chamber. The coupling device according to claims 10, characterized in that the sleeve portion, at least around the tube, is provided with a tapered support surface for the elements, whereby the diameter of said support surface in the longitudinal direction of the tube, decreases, increases, respectively, and whereby the support surface, by interaction with the elements, forms the pressure means to compress the elements against the tube. .13. A sealing piece that is suitable for being included in a coupling device for a tube to provide a seal around the tube, comprising a plurality of elements in slidable contact forming part of a substantially closed ring, and the elements of which increase radially in thickness, and whose part is further provided with pressure means for compressing the elements against the tube. The sealing part according to claim 13, characterized in that the elements are substantially cuneiform. The sealing part according to claim 14 or 15, characterized in that each element is provided with a notch on a first side and a projection on a second side of the element opposite the first side, whose notch and protrusion are suitable for interaction with a corresponding projection and notch, respectively, of a contiguous element. The sealing part according to claims 13-15, characterized in that the sealing part comprises a rubber ring, at least a portion of which can be located between the tube and the elements. 17. The sealing part according to claims 13-15, characterized in that the sides of the elements that contact the tube during use are partially made of rubber. The sealing part according to claim 13, characterized in that at least some elements are partially provided with a rough surface to make contact with the tube. The sealing part according to claim 18, characterized in that the rough surface is a toothed gripping element incorporated in the element. 20. The sealing part according to claim 19, characterized in that the elements are provided with a gripping ring which during use extends over at least part of the circumference of the tube. The sealing part according to claims 13-20, characterized in that at least one or some of the elements are made of a harder material than the tube, such as metal, and preferably stainless steel. 22. The sealing part according to claims 13-21, characterized in that the surface of the elements is arcuate in the circumferential direction corresponding to the radius of curvature of the tube. 23. A suitable element as part of a sealing piece in a coupling device for a tube, wherein the element has a thickness that increases in an uneven but monotonous manner from one end to the opposite end of said element in order to constituting a substantially closed ring when joined with a plurality of such additional elements. 24. The element according to claim 23, characterized in that the element is substantially cuneiform. The element according to claim 23, characterized in that the element is provided with a notch on a first side and a projection on a second side of the element opposite the first side, whose notch and projection are suitable for interaction with a projection and corresponding notch, respectively, of said contiguous elements. 26. The element according to claims 23-25, characterized in that the sides of the elements provided to make contact with the tube are partially made of rubber. 27. The element according to the claims 23-25, characterized in that the element is partially provided with a rough surface on the side provided to make contact with the tube. 28. The element according to claim 13, characterized in that the rough surface is a toothed gripping element incorporated in the element. 29. The element according to claims 23-29, characterized in that the element is made of a material harder than the tube, such as metal, and preferably stainless steel. 30. The element according to any of claims 23-28, characterized in that the surface of the element provided to make contact with the tube is arched in the circumferential direction corresponding to the radius of curvature of the tube.