CH654630A5 - Clamping connection for smooth round bodies, especially pipes and rods - Google Patents

Abstract

The clamping connection for smooth round bodies having a circular cross-section is intended especially for pipes (1, 2) but can also be used for rods and comprises a threaded pipe body (24), a threaded ring (21) or a cap nut and a gripping ring (26) with sharp edges (11) which point radially inwards. When the threaded ring (21) or the cap nut is screwed to the pipe body (24), the gripping ring (26) is pressed against the outer surface of the round body (1, 2) and holds it firmly. A seal (25) is arranged at a distance from the gripping ring (26), between the inner surface of the pipe body (24) and the outer surface of the round body (1). <IMAGE>

Description

** WARNING ** beginning of DESC field could overlap end of CLMS **.

PATENT CLAIMS 1. Clamping connection for smooth round bodies, in particular pipes or rods, with a threaded tubular body and a screw body, characterized in that between the round body (1,2), a frustoconical inner surface (10) of the screw body (4,21) and a stop (9) a gripping ring (6, 26) is arranged on the tubular body (3, 24) and has edges (11) on its radially inwardly directed surface section for clamping in the outer surface of the round body (1).

2. Clamping connection according to claim 1 for pipes, characterized in that the tubular body (3) has a circular extension (14) extending up to the inner wall of the tube, which serves as a transition piece between the tubes (1, 2).

3. Clamping connection according to claim 1, characterized in that the gripping body (6) is a wire, on the radial inside of which at least one groove (12) is incorporated.

4. Clamping connection according to claim 1 for pipes, characterized in that a seal (5,25) in an annular, from a space in which the gripping ring (6, 26) is arranged, separate recess on the inner surface of the pipe body (3) is arranged.

5. Clamping connection according to claim 4, characterized in that the seal (5) can be compressed by inserting the tube (1, 2).

6. Clamping connection according to claim 1, characterized in that the screw body is a practice nut (4) which engages in an external thread (8) on the tubular body (3) (Fig. 1).

7. Clamping connection according to claim 1, characterized in that the screw body is a ring (21) with an external thread (23) which engages in an internal thread (27) of the tubular body (24) (Fig. 3).

8. Clamping connection according to claim 7, characterized in that the outer end (22) of the ring (21) is crown-shaped for receiving a socket wrench, for which the round body (1, 2) serves as a guide.

9. Clamping connection according to claim 5, characterized in that the seal (25) has two compressible, against the tube (1) adjacent tongues (30) (Fig. 3).

10. Clamping connection according to claim 5, characterized in that the surface of the seal (25) bearing against the inner wall of the tubular body (24) runs in a wave-shaped manner (31) in axial section (FIG. 3).

The invention relates to a clamp connection according to the preamble of claim 1.

When laying pipes but also rods, they are usually screwed together using a union nut.

This design has the disadvantage that every pipe or

Rod ends often have to be threaded on the spot, which can be difficult to access at assembly points, is cumbersome without an electrical connection.

In an existing version (DE-OS 2 835 274) this problem is solved in that the tubes are placed in a sleeve and then clamped together in the radial direction by pressing.

This solution has the disadvantage that the pipe or rod connection can only withstand a limited mechanical load. The radial non-uniform loading of the pipe seal impairs its function, so that leaks can occur, especially at higher medium pressures.

Another disadvantage of this embodiment is that the mechanical strength can be increased with difficulty or not at all, because the cutting action of the clamping body can destroy the tube wall or practically prevents the tube's resistance to rotation against more than 900.

The object of the present invention is to provide a clamp connection for smooth round bodies, in particular pipes and rods, which does not have the disadvantages of existing designs.

The solution sought is to ensure a mechanically very strong connection that can withstand very high pressures.

A solution with a steadily increasing resistance to pressure being exerted on the clamping body is also to be sought.

To ensure that the function of the seal is not impaired, its symmetrical loading must also be ensured in the clamp connection created.

This object is achieved according to the invention with the teaching according to the characterizing features of claim 1.

Embodiments of this teaching are described in the further, dependent claims.

The solution described is characterized by high mechanical strength and, in the case of pipes, by absolute tightness, even at high medium pressures.

The pipe or rod connection is quick, easy and inexpensive to manufacture.

If necessary, the connection can easily be released, and the connection members can be used again.

An embodiment of the clamp connection according to the invention is explained in more detail below with reference to the drawing. Show it: 1 shows a longitudinal section through one half of a pipe clamp connection, Fig. 2 shows a section II of Fig. 1 ~ but according to a modified embodiment, and 3 shows a variant of FIG. 1.

In Fig. 1, two pipe ends 1, 2 and a threaded tubular body 3, a union nut 4, a seal 5 and a gripping ring 6 are shown. To connect the second tube 2, the tubular body 3 is symmetrical, a further union nut and a gripping ring being present in the part of the clamp connection which is not shown.

 For ## To make the clamp connection, first the union nut 4 and then the gripping ring 6 is pushed onto the first tube 1. The tubular body 3 is then pushed onto the tube 1 until the entire seal 5 bears against the outer surface of the tube 1.

In order to ensure that the correct length of the tubular body 3 is pushed onto the first tube 1, the gripping ring 6 can be used as a marking. Instead of the gripping ring, a color marking or the like can be used for this purpose.

The gripping ring 5 is preferably made of spring steel and is dimensioned such that it bears positively against the outer surface of the tube 1 or 2. The gripping ring 5 is not completely closed but has a gap so that it can be pressed together during the compression process during the clamping process. However, this gap can also run obliquely to the ring plane, so that the two ends of the non-closed ring overlap one another.

If the parts 3 to 6 are arranged on the tube 1, the

Union nut with an external thread 8 on the tubular body 3 engaged and tightened. As a result, the gripping ring 6 is pressed against a projection 9 on the tubular body 3. At the same time, a frustoconical surface 10 on the inside of the union nut 4 presses the gripping ring 6 radially inwards. The radial inner section of the gripping ring 6 has three sharp edges 11 which hook into the outer surface of the pipe 1 or 2, so that a firm pipe connection is created which can withstand high medium pressures.

Instead of the three edges 11 shown, two or even more than three can be provided. The number of edges 11 is e.g. depending on the materials used and the intended load. Instead of the round exit cross-section of the gripping ring, it is also possible, e.g. to use a ring with a frustoconical outer surface that bears against the surface 10. The version shown is a particularly inexpensive choice. Starting from a wire, the two grooves 12 between the edges 11 can be produced very inexpensively.

The seal 5 may possibly be completely omitted if the gripping ring 6 is designed accordingly and no flowable medium is used. In addition, the seal can be pressed together in such a way that an absolutely pressure-independent seal is created. The dashed line 13 shows the cross-sectional shape of the seal 5 before the tube 1 is inserted.

2 shows a slightly modified version of the clamp connection. In this embodiment, the tubular body 3 is provided radially on the inside with a circular extension 14, the inner radius of which corresponds to that of the tube 1, 2. The circular surface 15 can bear against the end face of the tube 1, 2. This approach 14 serves, among other things, for the correct positioning of the tubular body 3.

When assembling the connection, it is also possible to push the parts 3, 4, 5 and 6 as a combined unit onto the round body or bodies 1, 2, the gripping ring 6, e.g. is biased radially outwards by means of spring force.

To make the connection, only the union nut 4 must now be tightened.

3 shows an embodiment in which the union nut is replaced by a ring 21 with an external thread which engages in an internal thread 27 on the tubular body 24.

When the ring 21 is screwed into the tubular body 24, the gripping ring 6, which rests on the outside against the frustoconical surface 10 on the ring 21, is pressed into the outer surface of the tube or tube end 1, as was described in connection with FIG. 1.

In order to increase the force on the cutting edge or edge 11, only two are present, compared to three in the embodiment according to FIG. 1.

To improve the seal, the seal 25 is provided with a large number of indentations on the cross-sectional circumference. When the seal is pressed against the outer surface of the tubes 1, 2, this creates a large number of points of contact between the seal and the surfaces to be sealed. As a result, the effect of this seal 25 is greatly increased compared to that in FIG. 1.

The cross-sectional shape of the seal before the tube 1 is inserted is shown by line 20. On the inside, the seal has two tongues 30 which are pressed against the tube 1 when it is inserted. So that these tongues 30 do not jam between the tube body 24 and the tube 1, the wall 29 runs obliquely to the tube axis, so that a space for receiving the tongues 30 is created.

Grooves 31 are provided on the radially outer surface of the seal 25 and run in the circumferential direction of the seal 25.

The ring 21 is at the outer end e.g. designed as a crown nut in that regular projections 22 are interrupted by incisions. In this embodiment, a tool that can be attached perpendicular to the tube axis is used to tighten the ring 21, which is provided with pins attached at right angles to it, which engage in the incisions between the projections 22. The pins are expediently arranged on a semicircular plate which bears against the tube 1 serving as a guide during screwing. This guide facilitates or accelerates the connection of pipes 1 and 2.

Instead of the crown shape, the outer end of the ring 21 can also have other shapes, e.g. normal nut shape or other shape, which ensures a quick screwing.

The versions shown can be used in particular for pipes, but also for rods. The individual parts 3 to 6 or 21, 24, 25, 26 are relatively inexpensive to manufacture in large numbers. Above all, it is important that no threads have to be attached to pipes or rods at the assembly point.

Claims (10)

PATENT CLAIMS 1. Clamping connection for smooth round bodies, in particular pipes or rods, with a threaded tubular body and a screw body, characterized in that between the round body (1,2), a frustoconical inner surface (10) of the screw body (4,21) and a stop (9) a gripping ring (6, 26) is arranged on the tubular body (3, 24) and has edges (11) on its radially inwardly directed surface section for clamping in the outer surface of the round body (1). 2. Clamping connection according to claim 1 for pipes, characterized in that the tubular body (3) has a circular extension (14) extending up to the inner wall of the tube, which serves as a transition piece between the tubes (1, 2). 3. Clamping connection according to claim 1, characterized in that the gripping body (6) is a wire, on the radial inside of which at least one groove (12) is incorporated. 4. Clamping connection according to claim 1 for pipes, characterized in that a seal (5,25) in an annular, from a space in which the gripping ring (6, 26) is arranged, separate recess on the inner surface of the pipe body (3) is arranged. 5. Clamping connection according to claim 4, characterized in that the seal (5) can be compressed by inserting the tube (1, 2). 6. Clamping connection according to claim 1, characterized in that the screw body is a practice nut (4) which engages in an external thread (8) on the tubular body (3) (Fig. 1). 7. Clamping connection according to claim 1, characterized in that the screw body is a ring (21) with an external thread (23) which engages in an internal thread (27) of the tubular body (24) (Fig. 3). 8. Clamping connection according to claim 7, characterized in that the outer end (22) of the ring (21) is crown-shaped for receiving a socket wrench, for which the round body (1, 2) serves as a guide. 9. Clamping connection according to claim 5, characterized in that the seal (25) has two compressible, against the tube (1) adjacent tongues (30) (Fig. 3). 10. Clamping connection according to claim 5, characterized in that the surface of the seal (25) bearing against the inner wall of the tubular body (24) runs in a wave-shaped manner (31) in axial section (FIG. 3). The invention relates to a clamp connection according to the preamble of claim 1. When laying pipes but also rods, they are usually screwed together using a union nut. This design has the disadvantage that every pipe or Rod ends often have to be threaded on the spot, which can be difficult to access at assembly points, is cumbersome without an electrical connection. In an existing version (DE-OS 2 835 274) this problem is solved in that the tubes are placed in a sleeve and then clamped together in the radial direction by pressing. This solution has the disadvantage that the pipe or rod connection can only withstand a limited mechanical load. The radial non-uniform loading of the pipe seal impairs its function, so that leaks can occur, especially at higher medium pressures. Another disadvantage of this embodiment is that the mechanical strength can be increased with difficulty or not at all, because the cutting action of the clamping body can destroy the tube wall or practically prevents the tube's resistance to rotation against more than 900. The object of the present invention is to provide a clamp connection for smooth round bodies, in particular pipes and rods, which does not have the disadvantages of existing designs. The solution sought is to ensure a mechanically very strong connection that can withstand very high pressures. A solution with a steadily increasing resistance to pressure being exerted on the clamping body is also to be sought. To ensure that the function of the seal is not impaired, its symmetrical loading must also be ensured in the clamp connection created. This object is achieved according to the invention with the teaching according to the characterizing features of claim 1. Embodiments of this teaching are described in the further, dependent claims. The solution described is characterized by high mechanical strength and, in the case of pipes, by absolute tightness, even at high medium pressures. The pipe or rod connection is quick, easy and inexpensive to manufacture. If necessary, the connection can easily be released, and the connection members can be used again. An embodiment of the clamp connection according to the invention is explained in more detail below with reference to the drawing. Show it: 1 shows a longitudinal section through one half of a pipe clamp connection, Fig. 2 shows a section II of Fig. 1 ~ but according to a modified embodiment, and 3 shows a variant of FIG. 1. In Fig. 1, two pipe ends 1, 2 and a threaded tubular body 3, a union nut 4, a seal 5 and a gripping ring 6 are shown. To connect the second tube 2, the tubular body 3 is symmetrical, a further union nut and a gripping ring being present in the part of the clamp connection which is not shown.  For ## To make the clamp connection, first the union nut 4 and then the gripping ring 6 is pushed onto the first tube 1. The tubular body 3 is then pushed onto the tube 1 until the entire seal 5 bears against the outer surface of the tube 1. In order to ensure that the correct length of the tubular body 3 is pushed onto the first tube 1, the gripping ring 6 can be used as a marking. Instead of the gripping ring, a color marking or the like can be used for this purpose. The gripping ring 5 is preferably made of spring steel and is dimensioned such that it bears positively against the outer surface of the tube 1 or 2. The gripping ring 5 is not completely closed but has a gap so that it can be pressed together during the compression process during the clamping process. However, this gap can also run obliquely to the ring plane, so that the two ends of the non-closed ring overlap one another. If the parts 3 to 6 are arranged on the tube 1, the ** WARNING ** End of CLMS field could overlap beginning of DESC **.