DD283451A5 - PIPE CLAMP CONNECTION - Google Patents

Abstract

The pipe clamp connection is formed by a coupling housing, a clamping ring and a cap screw or a union nut. The Kupplungsgehaeuse has on the inside an Innenkonusflaeche with a very small cone angle. The coupling housing also has a screw thread either for a cap screw or a union nut. The Auszenseite the clamping ring is conical and matched to the Innenkonusflaeche the Kupplungsgehaeuse. On its inside, the clamping ring is provided with circumferential ribs. The clamping ring has at its slimmer end a ring-shaped closed length portion. In the adjoining middle length section of the clamping ring has a helically extending in the radial direction continuous helical slot whose sense of winding is opposite to the sense of winding of the screw thread on Kupplungsgehaeuse. Zweckmaeszigerweise the length of the section at the thicker end of the clamping ring is in turn closed ringfoermig. The cap screw or the union nut has a kreisringfoermige Anlageflaeche for the system at the rear end face of the clamping ring. Fig. 4 {pipe clamp connection; Kupplungsgehaeuse; Clamping ring; About union screw; Innenkonusflaeche; Ring ribs; Spiral slot; Screw thread; Auszenseite; Cone angle}

Description

Field of application of the invention

Pipe systems are generally composed of individual tubes of different lengths and sometimes of different diameters, which are connected at their ends by means of pipe couplings. Most are still at different points of the piping systems of different types, such as taps, valves or gate valves available, which are connected in the same way with the adjoining pipes. All these joints must have the same tightness and strength as the individual pipe sections. This applies to metal pipes as well as pipes made of plastic. The latter can be made exclusively of plastic, namely of a thermoplastic material. But they can also consist of a composite material in which reinforcements and reinforcing elements, in particular in the form of glass fibers, are embedded in a thermosetting plastic. These are briefly referred to as GRP pipes. Since the GRP pipes are already produced in layers, it is possible to produce different layers of the pipe from different plastics, which are particularly well suited for their respective intended task.

Characteristic of the known state of the art

In metal pipes great strength mostly coupling elements made of metal, so-called fittings, are used, in which the pipe ends and the coupling parts are provided with threads cut therein, so that the pipes and the coupling parts can be screwed directly together. In addition, there are still cutting ring connections in which a cutting ring is pressed with his front cutting in a Innenkon us hi, so that the end cutting narrows and cuts into the tube that surrounds them.

At best, this type of pipe connection can still be used for pipes of metals of lesser strength, but not more for pipes made of plastic.

In plastic pipes, there are permanent connections in which the pipe sections are connected directly by welding or are connected by gluing either with each other or with each other by means of coupling elements. When welding two pipe ends occurs on the inside of the weld usually a stronger Schweißgrat on, which narrows the flow area of the pipe at the junction considerably and in the passage of a fluid in any case leads to turbulence in the fluid. Adhesive joints require great care in their execution. This requires skilled personnel. Even in the presence of such specialized personnel, however, the adhesive joints on a construction site can not always be manufactured with sufficient reliability. The adhesive bond is also susceptible to certain fluids and / or to certain ingredients of the fluids, so that it can not always be used for that reason alone. It is a great disadvantage that this susceptibility to the fluid itself or against ingredients of the fluid can turn out only after the connection has been established over time and that under certain circumstances the entire line system must be replaced. A further great disadvantage of both the welded joint and the adhesive joint is that the joints can not subsequently be loosened, even if changes in the routing are required or if subsequent connections have to be made subsequently.

For piping systems made of plastic pipes, there are also releasable connections, namely as pipe clamp connections of different types. Allen has in common is that any annular deformable clamping member, a clamping ring is clamped axially between two relatively movable conical contact surfaces and da ßda at, that is, by the elastic deformation occurring, the clamping ring on the one hand on the pipe and on the other hand on a tightly abuts the other part of the pipe coupling and thereby tightly connects the abutting parts of the pipes. In most of these pipe clamp connections, a support sleeve is often required, which is either inserted as a loose part in the pipe end, or which is integrally formed on the coupling body and is pushed into the tube during assembly of the tube with the coupling part.

These support sleeves of any kind have the great disadvantage that they give a considerable cross-sectional constriction of the pipeline, which is always associated with a correspondingly large pressure drop and often with higher noise education. In piping systems with a large number of fittings included in the system, the pressure drop at the individual coupling points can add up to a very high value. The use of support sleeves has the further great disadvantage that for the insertion of the support sleeve into the tube or vice versa, for the insertion of the tube in the coupling body with a η shaped support sleeve, only the tube end must be heated. Improper heating may damage the pipe. There are also pipe clamp connections without support sleeve. In them, the clamping rings are always slotted continuously at a circumferential location, because of the absence of the support sleeve, the elastic deformation of the tube, in particular in the region of the conical surfaces between the support ring and cap screw are relatively large. In addition, the dimensional tolerances are known to be very large and therefore a total of a large diameter change and / or diameter tolerance must be bridged, especially in thermoplastic pipes. Because of this longitudinal slot the clamping rings are not able to take over the seal, which is why in addition an O-ring is required as the actual sealing element. It is inserted into a recess on the coupling body. In one type of pipe clamp connections of the O-ring is inserted into a arranged on the inside of the coupling body groove with two shoulders and pressed by the fluid itself against the outside in the printing direction shoulder, thereby producing the sealing effect. In another type of pipe clamp connections of the O-ring is inserted into an axial recess of the coupling body, where he puts it on a shoulder of the recess. In addition, on the other side of the O-ring to an inserted raceway, which is pressed by the cap screw of the pipe clamp against the O-ring, so that it is elastically deformed in the remaining cavity and he tightly applies in the radial direction on the one hand to the coupling body and on the other hand on the tube outside , In the former pipe clamp connection, the pipe is held by a clamping ring which sits outside the O-ring on the pipe and is pressed by a union nut against the coupling body, wherein the union nut has an inner cone surface which cooperates with an outer cone surface on the clamping ring and when tightening the nut for it ensures that the existing on the inside of the clamping ring circumferential annular ribs

with sharp inner edge due to the elastic deformation of the clamping ring press into the outside of the tube and dig. In the second-mentioned Rohrklemmverbindung.liegt the clamping ring between the stop ring for the O-ring and one of which remote inner cone surface of a cap screw. This clamping ring is also deformed radially inwardly when tightening the cap screw, so that even with him the inner ring ribs dig into the outside of the tube. Through the neck of the cap screw at the same time the stop ring is pressed against the O-ring.

In these two types of pipe clamp connections, the O-ring ensures the sealing of the joint, while the annular ribs on the inside of the clamping ring provide the necessary holding force between the pipe and the coupling, which can not apply the O-ring alone, but which is required so that Pipe system is not pulled apart under the pressure effect of the fluid. These pipe clamp connections with O-ring have the great disadvantage that the O-rings have no very high creep resistance and they are especially for fluids with changing pressure and especially changing temperature, as is the case for example with hot water pipes in households, after a more or less long Change time, whereby their sealing effect diminishes or disappears completely. In particular, in this case the increasing creep of the material of O-rings is disadvantageous.

These pipe clamp connections still have the disadvantage that the clamping ring is clamped between the tube and an inner cone surface of the union nut or cap screw, so that a considerable torque is exerted on the tube when tightening the union nut or cap screw on the adjoining conical surfaces. In the event that already connected to the pipeline fittings, the twisting of the tube must be prevented. If the pipe is held to the existing fittings, it may happen that the clamping connection is loosened again. If the pipe itself is held tight, it can happen that the pipe is damaged because it requires pliers.

In these pipe clamp connections, the clamping force of the clamping ring is generated by the interaction of the conical surfaces on the one hand on the clamping ring and on the other hand on the union nut or cap screw. Since the flank angle relative to the longitudinal axis of the pipe coupling is relatively steep, the conical surfaces have only a very small axial extent, so that the force exerted by the clamping ring on the tube radial force is concentrated on a very short length of the tube. As a result, the pipe is locally exposed to a very high stress, which means that the tube is elastically relatively strong constricted at this point. In addition, there is a risk that the annular ribs of the cutting ring dig on this short length section very strong in the tube outside and thereby cause a significant notch effect on the tube, which focuses awf a relatively short length. This significantly reduces the mechanical fatigue life of the pipe.

Object of the invention

The aim of the invention is to avoid the disadvantages of the known compounds.

Explanation of the essence of the invention

The invention has for its object to provide a pipe clamp connection, which has a greater creep resistance than the known pipe clamp connections.

According to the invention, the pipe clamping connection comprises the following elements

- A hollow coupling body has for the installation of a clamping ring on an inner cone surface, the large diameter of the free end face of the coupling body is facing at the mouth of its cavity,

- The coupling body has, in connection to its free end face, a central to the inner cone surface arranged internal thread for a cap screw or an external thread for a cap nut,

the cap screw or cap nut has an end-face contact surface for the clamping ring,

- The clamping ring has on its circular cylindrical inner side a number of circumferential, self-contained annular ribs, which are arranged in a respective normal plane to its longitudinal axis,

the ring ribs have a sharp edge on the inside edge,

- The clamping ring has on its outer side an outer cone surface which is at least approximately matched to the inner cone surface of the coupling body,

characterized by the following features:

the inner cone surface on the coupling body and the outer cone surface on the Klemmrin.g have a very small angle of inclination with respect to the longitudinal axis,

- On the clamping ring, the contact surface for the cap screw or union nut and the cap screw or union nut, the contact surface for the clamping ring is at least approximately flat and aligned normal to the longitudinal axis of the clamping ring,;

- The clamping ring has a helically extending, radially continuous slot which ends in the axial direction at the front end of the clamping ring with the smaller cone diameter at a certain distance from the end face of the clamping ring,

- The sense of winding of the helical slot is opposite to the winding sense of the thread between the coupling body and the cap screw or union nut.

The clamping ring advantageously has at its rear end with the larger cone diameter a length of a certain length, which is not slotted.

Preferably, this unslotted rear longitudinal portion of the clamping ring has a circular cylindrical outer surface. The inner cone surface of the coupling body has an inclination angle with respect to its longitudinal axis which is at least approaching 4.5 °, the outer cone surface of the clamping ring has an inclination angle with respect to its longitudinal axis which is up to 1 ° smaller than the inclination angle of the inner cone surface of the coupling body.

The unslit length portion at the front end of the clamping ring has an axial extent which is at least equal to the axial distance between two adjacent annular ribs on the inside of the clamping ring.

Preferably, the axial extent of the unslotted longitudinal section at the front end of the clamping ring is at least approximately 0.1 times the clear width (nominal diameter) of the clamping ring (nominal diameter) and at the same time the outer diameter of the tube.

The annular ribs advantageously have a radial height of at least approximately 0.4 mm.

The annular ribs preferably have an axial distance between 1.2 and 1.4 mm.

Preferably, the front side of the associated front edge of the annular ribs is aligned normal to the longitudinal axis of the clamping ring and the back edge of the sharp edge of the annular rib to the bottom of the leading edge of the subsequent annular rib in longitudinal section rounded at least approximately concave.

The unslit length portion at the rear end of the clamping ring has an axial extent which is at least approximately 0.1 times the nominal diameter of the clamping ring. ·

The helical slot has 4 full turns and the pitch of the spiral slot is preferably 0.1 times the nominal diameter.

The coupling body and the clamping ring are made of a metal whose strength is higher than that of the material of the outside of the pipe to be coupled or at least the outside thereof.

In addition, the following features are advantageous:

- The clamping ring is offset in the region of the unslotted front longitudinal section in a subsequent to the front end portion of its outer cone surface parallel to this inward by a certain amount,

the undersize of this stepped portion with respect to the remaining outer cone surface is preferably 0.1 mm in the radius,

the axial extent of the stepped portion is preferably 2.0 mm,

Preferably, the recessed portion is followed by a peripheral groove which is preferably 0.1 mm deep in relation to the stepped portion and which is preferably 0.5 mm wide.

- The rear wall of the groove connects sharp-edged to the outer cone surface of the clamping ring,

the front end face of the clamping ring is complete and the stepped section is coated with a corrosion inhibitor close to the groove,

- The helical slot ends at the front end of the clamping ring at least approximately 0.5 mm in front of the groove. The anticorrosive agent consists of polyethylene, polytetrafluoroethylene, polyamide or another thermoplastic material and the anticorrosive agent is preferably applied in powdered starting form in the fluidized bed method on the clamping ring.

The clamping ring and preferably also the coupling body are made of plastic, in particular of glass fiber reinforced plastic.

On the clamping ring, the glass fiber reinforcement is aligned in the circumferential direction in the region of the annular ribs. Preferably, in the material of the annular ribs of the glass fiber content is greater than in the material of the remaining parts of the clamping ring.

The clamping ring is suitably chamfered at its rear end on the inside.

The chamfer preferably has an angle of inclination of 30 ° with respect to the longitudinal axis of the clamping ring and preferably an axial extent of 1.0 mm.

The clamping ring is also chamfered at its front end on the outside.

The chamfer preferably has here an angle of inclination of 30 ° with respect to the longitudinal axis of the clamping ring and preferably an axial extent of 0.5 mm.

In a further advantageous embodiment, the invention has the following features:

- On the coupling body connects to the inner cone surface for the clamping ring on a circular cylindrical surface whose inside diameter is greater than the outer diameter of the rear end of the clamping ring it is;

- The transition point between the inner cone surface and the circular cylindrical surface is located within the longitudinal portion of the coupling body, which assumes the clamping ring after tightening the cap screw or union nut;

- Between the rear end face of the clamping ring and the front contact surface of the cap screw or union nut a Stemmring is inserted, the inside diameter is not smaller than the nominal diameter of the clamping ring and the outer diameter is at least approximately equal to the clear width of the circular cylindrical surface on the coupling body in the untensioned rest state;

- The two end faces of the Stemmringes run parallel to each other and have the shape of the lateral surface of a truncated cone;

- The inclination of the generatrices of the two frustoconical faces of the stemming ring against the center axis of the Stemmringes is preferably in the range of 60 ° -75 °,

- The U mfa ngsf laugh the Stemm ring it is formed in the untensioned rest state as circular cylindrical surface and formed at least the peripheral edge at the transition to the inner end face of the Stemmringes sharp-edged.

In the slotted length portion of the clamping ring, the radial depth of the recesses between the annular ribs decreases from the largest dimension at the front end of the slotted longitudinal section to zero at the rear end of the slotted longitudinal section

 The pipe clamping connection according to the invention with a union nut is characterized by the following features:

- On the union nut, the contact surface for the clamping ring is formed by the end face of a collar-shaped extension, which connects to the annular collar of the union nut in the axial direction and extends in the direction of the internal thread of the union nut;

- The annular extension has

A clear width which is not smaller than the clear width of the rear end of the clamping ring, and

• an outer diameter which is not larger than the outer diameter of the rear end of the clamping ring.

The coupling body has on its inside a covenant, the clear width not smaller than the inside diameter of the tube

The tube facing the end face of the collar is at least approximately flat and aligned normal to the longitudinal axis of the coupling body.

Preferably, the inside of the coupling body in connection to the collar on a circular cylindrical surface which has a certain axial extent and the inside width is at least approximately equal to or slightly larger than the outer diameter of the tube.

The circular cylindrical surface is adjoined by an inner cone surface whose angle of inclination relative to the longitudinal axis of the coupling body is preferably in the angular range of 30 ° -45 °.

The inner cone surface for the clamping ring adjoins the inner cone surface.

Finally, the pipe clamp connection according to the invention is characterized by the following features:

- The coupling housing has on its inside a covenant, whose inside width is not smaller than the inside diameter of the tube;

- Of the pipe facing the front side of the collar has an outer annular region at least approximately the shape of a flat end face, which is aligned normal to the longitudinal axis of the coupling housing;

- At the inwardly adjacent inner ring area of the Bu η of an axial extension is arranged or formed,

• whose inner peripheral surface is at least approximately formed as a circular cylindrical surface whose inside diameter is not smaller than the inside diameter of the tube, and

• whose outer peripheral surface is formed either as a circular cylindrical surface or, preferably, as a lateral surface of a truncated cone whose generatrices relative to the longitudinal axis of the coupling housing have an inclination angle between 20 ° and 45 °;

- The co-operating with the coupling housing end of the tube is provided on its inside with a matched to the axial extension on the coupling housing recess.

When tightening the nut as an actuator of the pipe clamp, the clamping ring is first pressed in the axial direction in the very slim inner cone of the coupling body. In this case, initially narrowed elastically to the extent that the Verschwiebewiederstand increases at the clamping ring at the unslotted longitudinal section at its front end, the axial contact force between the planar contact surface at the rear end of the clamping ring and the likewise flat contact surface on the actuator to. This increased the frictional force between these two contact surfaces in the circumferential direction. As a result of the helical slot thereby narrow the band-like adjacent turns of the clamping ring. As a result, their outer conical surface lies less strongly against the inner conical surface of the coupling body, while their cylindrical inner side with the annular ribs rests ever more strongly on the raw rap. In this case, the unslit length portion is pushed further and further into the inner cone of the coupling body at the front end of the clamping ring, until it rests fully on the tube due to its inward elastic deformation takes place in the radial direction. With larger undersize of the tube with respect to the nominal diameter of the clamping ring and / or with greater radial compliance of the tube, the unslotted length portion can also plastically deform, d. H. constrict permanently. In the narrowing of the unslit length portion, the annular ribs of this length section dig into the outside of the tube and provide a good seal between the tube and the clamping ring. On the outside, the adjoining very slim conical surfaces on the one hand the unslotted longitudinal portion of the clamping ring and on the other hand of the coupling body for a very good seal between these two parts, without the need for another sealing element, such as in the form of an O-ring needs.

During this process, the turns of the clamping ring adjoining the unslotted longitudinal section also gradually pass into an axial region of the coupling ring, in which they not only rest firmly on the pipe due to the constriction, but by their outer conical surfaces become fixed to the inner cone surface of the coupling body invests. In this case, the existing on the inside of the turns of the clamping ring dig the ring ribs in the outside of the tube. Since in the subsequent to the unslotted length portion turns of the slotted longitudinal section of the clamping ring, the wall thickness towards the rear end steadily increases, increases in these turns and the moment of resistance to bending steadily, and that progressively. This has the consequence that the occurring under the effect of when tightening the cap screw or union circumferential force on the rear face of the clamping ring, the turns of the slotted longitudinal section with decreasing intensity create the pipe and their annular ribs dig accordingly with decreasing intensity in the pipe wall. As a result, the tube is probably clamped and held on the entire length of the clamping ring. But it occurs at any point in the axial region of the clamping ring, a local mechanical overuse of the tube. Because of the decreasing after the rear end of the clamping ring burial depth of the annular ribs unfavorable notch effect of this annular ribs is avoided at the transition to the free pipe section outside of the clamping ring. Due to the large number of more or less strongly buried in the outside of the tube annular ribs or annular rib sections a very high extraction resistance is achieved, which prevents the tube is pulled out of the compressive forces of the fluid in the piping system from the couplings. Due to the failure of sealing elements made of elastomeric materials, aging processes at the seal can not occur. As a result of the clamping of the pipe end in a larger length section with a correspondingly wide distribution of the radial and axial clamping and holding forces acting there, local overstressing of the pipe is not to be feared. As a result, such a pipe clamp connection achieves a creep rupture strength which at least comes close to, if not equal to, that of the pipe outside the pipe clamp connection and thus goes far beyond that which can be expected with conventional pipe clamp connections.

Another advantage of this pipe clamp connection is that the unslit length of the clamping ring has the lowest wall thickness and therefore is easily deformed even in the closed ring shape. Due to this and due to the great flexibility of the turns in the slotted area of the clamping ring, the thread for the cap screw or nut can be kept relatively coarse. It can even be used in metal fittings for the pipe diameter of the usual pipe thread. This in turn makes it possible, for example, in the coupling bodies screw in a normal stopper or attach a fitting with the usual pipe thread on the coupling body in case of need. As a result, transition pieces can be saved with different thread formation.

In one embodiment of the pipe clamp connections according to claim 2, the production of the helical slot is facilitated because the clamping ring can be clamped at both ends. The unslit Lan gene section also prevents the leakage of the last turn in a pointed end, which would be exposed as a result of decreasing bending resistance torque increasingly constricting effect of frictional engagement with the cap screw or nut union. also

This avoids a sharp point at the rear end of the clamping rings, which could give rise to injuries when handling the clamping rings, especially if the tip would be bent by damage. Due to the cylindrical outer surface of the unslit length portion is avoided that this longitudinal section jammed in the outer cone of the coupling body before the remaining parts of the clamping ring have been pushed far enough into the inner cone of the coupling body.

By an embodiment of the pipe clamp connection according to claim 3, a balanced ratio between on the one hand the axial displacement and axial displacement force and on the other hand a sufficiently large radial and axial clamping force is achieved. This is especially true for the GRP pipes, which can be produced with relatively small dimensional tolerances. For pipes that are made exclusively of a thermoplastic material, which generally have larger dimensional tolerances, it may be appropriate to make the angle of inclination of the inner cone surface on the coupling ring larger, up to about 10 °. By reducing the angle of inclination of the Au ßenkonusf laugh the clamping ring is achieved that the, the axial collapse of the turns of the slotted longitudinal section of the clamping ring entering enlargement of the inclination angle of the clamping ring enveloping lateral surface is compensated again and is aligned with the constant inclination angle of the inner cone surface of the coupling body. Due to the configuration of the pipe clamp connection according to claim 4, a particularly good sealing effect of the unslit length of the clamping ring is achieved.

In one embodiment of the pipe clamp connection according to claim 5 ensures that when tightening the cap screw or nut the annular ribs of the clamping ring on the one hand dig sufficiently far into the outside of the pipe in question and both seal well to the outside, as well as mechanically hold and on the other hand, especially at GRP pipes whose glass fiber reinforcement does not or at least does not cut through in a harmful way. The normally aligned leading edge of the ring ribs ensures a very high pull-out resistance for the clamped tube. The rounding of the back flank ensures that the material on the outside of the tube is not displaced too much to the side, possibly detaching itself from the underlying material layers.

By an embodiment of the pipe clamp connection according to claim 6, both a good Einspannmöglichkeit for the slits of the central longitudinal section created, as well as a sufficient stabilization of the turns achieved with a central guide.

By an embodiment of the pipe clamp connection according to claim 7, a balanced relationship between on the one hand a secure clamping and holding the tube and on the other hand, a limitation of the total length of the pipe clamp connection is achieved.

In one embodiment of the pipe clamp connection according to claim 8 it is achieved that the annular ribs reach a sufficient strength for the penetration into the outside of the tube and a sufficient bending strength when pulling forces occur.

With an embodiment of the pipe clamp connection according to claim 9, the clamping ring on the front side and on the stepped portion of its peripheral surface can be specifically or generally prophylactically protected against corrosive attacks of the fluid or constituents of the fluid by the corrosion protection agent. As a result, for example, a clamping ring made of brass to be protected against Entzinkungserscheinungen without the presence of either very pure water or special aggressive waters equal to a special material must be used for the clamping ring. The stepped portion of the outer cone surface on unslotted longitudinal portion of the clamping ring serves to absorb the corrosion protection agent with a layer thickness of preferably 0.1 mm, without being scraped off during insertion and especially when pressing the clamping ring in the outer cone of the coupling housing of the latter. The groove at the end of the stepped portion serves to receive the parts of the anticorrosion agent, which protrude beyond the geometric circumferential surface of the outer cone surface of the clamping ring and thereby pushed away during the pressing of the clamping ring. The sharp-edged transition from the rear wall of the groove to the non-stepped outer cone surface causes the corrosion inhibitor adhered to the inner cone surface of the coupling body to be scraped off when the clamping ring is pressed in, so that these parts of the rust preventive do not uniformly fit the unstressed portion of the unslotted one Can affect length of the clamping ring. Characterized in that the end of the helical slot is set away by a certain amount of the groove, it is ensured that a sufficiently wide Aniagefläche the unslotted longitudinal portion of the clamping ring is ensured on the inner cone surface of the coupling body, which serves for the outer sealing of the clamping ring. With a further development of the pipe clamp connection according to claim 10, the corrosion protection can be applied relatively easily and safely, the selection of the corrosion inhibitor depends on the circumstances of the site. By means of an embodiment of the pipe clamp connection according to claim 11, in particular when using glass fiber reinforced plastic for the clamping ring and the coupling body, these parts have the same or at least similar properties with respect to elastic deformations and / or dimensional and dimensional changes due to temperature changes. As a result, the behavior of the pipe clamp connection and the pipes coupled thereto are approximated. In a further development of the pipe clamp connection according to claim 12 ensures that the annular ribs on the inside of the clamping ring have a relatively high dimensional stability, which ensures a safe penetration and digging on the outside of the festzuhaltenden pipes, the outer layer usually has a relatively lower strength ,

With an embodiment of the pipe clamp connection according to claim 13 it is achieved that the pipes can still be inserted easily and without damage on the one hand of the clamping ring and on the other hand of the tube itself in the pipe clamp, if the latter is already pre-assembled and the clamping ring loosely seated in the inner cone of the coupling body and held by partially bolted cap screw or the partially screwed cap nut and covered.

By a pipe clamp connection according to claim 14, the clamping ring can be easier to use in the coupling body, especially as the helical slot of the clamping ring has a lower dimensional stability, as an unslotted ring and he is thereby exposed during storage and handling rather minor changes in shape.

In one embodiment of the pipe clamp connection according to claim 15 when tightening the cap screw or union nut inserted between it and the clamping ring Stemmring deformed so that its outer edge digs into the matching circular cylindrical surface of the coupling body, the Stemmring in a sense with the

Clamping body caulked so that the clamp the tube de and sealing clamping ring is also held in its clamping and sealing position when the cap screw or nut, for whatever reason, loosens or otherwise gives way. This embodiment is accordingly for such pipe connections into consideration, on the one hand no longer need to be solved and on the other hand require an increased level of security against loosening and / or leaking. This is especially true for concealed pipelines or for such piping, which are no longer readily accessible later.

With an embodiment of the pipe clamp connection according to claim 16, the radial depth of the recesses between the annular ribs of the decreasing from the front to the rear end of the clamping ring penetration depth of the annular ribs in the outside of the tube follows. Characterized the peripheral surface of the recesses for guiding and holding the clamped tube is used in the middle and rear of the clamping ring, which is thus not hollow in this area between the annular ribs. As a result, a possible notch effect of the annular ribs, especially in the rear region of the clamping ring, is prevented at a bending load of the clamped raw res. This is especially true for those embodiments of the clamping ring, in which at the end of an unslotted longitudinal section is present, which receives a smooth inner surface in the embodiment according to claim 16.

By using a union nut instead of a cap screw of the coupling body can therefore be made considerably shorter because in general because the thread can be mounted on the outside of the coupling body in about the same length section in which the Innenkonusf is located on the inside of the clamping ring for the clamping ring , In addition, it is usually also the outer diameter of the coupling body can be reduced, because the internal thread for the cap screw must have a larger inside diameter than the inner cone surface at its large diameter. In one embodiment of such a pipe clamp connection according to claim 17, a larger axial actuating travel for the rear end of the clamping ring is made possible by the collar-shaped projection on the union nut, because in case of need, the extension can be moved into the coupling body. This reduces the dependence on compliance with low manufacturing tolerances in the pipe clamp connection and especially in the pipe. In an embodiment of the pipe clamp connection according to claim 18 is ensured by the federal government that an inserted into the pipe clamp pipe is inserted just as far as it is necessary for a secure clamping and sealing, and thereby simultaneously avoided that the pipe accidentally over the right position is pushed out into the area of the subsequent pipe clamp connection, where then the pipe to be inserted there could no longer reach the correct position. Characterized in that adjoins the collar a circular cylindrical surface which is matched to the outer diameter of the tube, the inserted into the pipe clamp pipe in the coupling body itself is exactly centered, that is independent of the random axial and radial position of the clamping ring in the coupling body. By the adjoining the Kreiszyiinderfläche Innenkonusfläche the insertion of the tube is facilitated in the length section with the Kreiszyiinderfläche and at the same time prevents the tube abuts before reaching the Kreiszyiinderfläche. This embodiment is always preferred instead of the basic form used when the resulting in her extension of the body for their use is not a hindrance.

With a designed according to claim 19 pipe clamp connection can also plastic pipes with a greater elastic compliance, such. As pipes made of a thermoplastic material, are securely connected to each other or connected to a fitting. The axial projection on the coupling body serves as a support collar for the pipe end, which is supported with the matching recess on its inner side on the support collar in the radial direction. It is thereby achieved that when tightening the cap screw or union nut, the pipe wall under the action of the radial force of the clamping ring can not escape inwards and that the annular ribs of the unslotted length of the clamping ring can dig into the pipe wall and can reliably seal the pipe. It also holds the pipe securely.

embodiments

In the following the invention will be explained in more detail with reference to several embodiments shown in the drawing. Show it:

1 shows a longitudinal section of a pipe coupling with two pipe clamp connections, each with a clamping ring. 2 shows a longitudinal section of one of the clamping rings;

3 shows an enlarged detail of the clamping ring of FIG. 2;

4 shows a detail of a longitudinal section of a further embodiment of the clamping ring; 5 is a fragmentary and enlarged longitudinal section of a modified embodiment of the

Clamping ring; 6 shows a detail of a longitudinal section of a further embodiment of the pipe clamp connection in FIG

pre-assembled condition; 7 shows a detail of a longitudinal section of the embodiment of the pipe clamp connection according to FIG. 6 in the assembled state;

8 shows part of a longitudinal section and partly a view of an embodiment of the pipe clamp with union nut. Fig. 9: partly a longitudinal section and partly a view of an embodiment of the pipe clamp connection with support collar.

The apparent from Fig. 1 pipe coupling 10 connects two pipes 11 and 12 with each other. These two tubes are made of a composite material, namely glass fiber reinforced plastic, which is why these tubes are also referred to as GRP tubes. The pipe coupling 10 has for each of the two tubes 11 and 12 each have a pipe clamp connection 13 and 14, of which one each anje one of the ends of the pipe coupling 10 is arranged in mirror-image arrangement to the other. The following statements with respect to the pipe clamp connections 13 and 14 apply in the same or at least analogously to other types of pipe couplings, such as those in T-shape, or for fittings of various kinds, with at least one pipe clamp connection corresponding to the pipe clamp connections 13 and 14th are equipped

 Each of the two pipe clamp connections 13 and 14 each have a coupling housing 15 or 16. They are among each other

the same design. They each form part of a one-piece body 17. This is made of metal, in particular brass. But other materials come into consideration, as they are commonly used in piping systems. The main body 17 is an elongated hollow body with an approximately cylindrical shape. In the longitudinal center of the main body 17, and thus at the inner end of each of the two coupling body 15 and 16, an inner collar 18 is present on G round body. Whose inner circular cylindrical Umfangsf pool has a clear width, which is suitably not smaller than the clear width of each other to be coupled GFRP tubes 11 and 12, but at most is slightly larger. The inner collar 18, with its two flat end faces, which are aligned normal to the longitudinal axis of the base body 17, a stop for the end faces of the two GRP pipes 11 and 12, which serves to ensure that the two GRP pipes 11 and 12 only ever can be pushed into the center of the body 17 in this and can not be pushed over from the area of a pipe clamp connection to the area of the other pipe clamp connection.

In view of the fact that the two pipe clamp connections 13 and 14 are mirror-inverted with each other, the following explanation is limited to the right in Fig. 1 pipe clamp connection 14, which also applies to the pipe clamp connection 13.

The pipe clamp connection 14 has, in addition to the coupling housing 16 as further parts, a cap screw 19 and a clamping ring 20.

The coupling body 16 has two longitudinal sections 21 and 22. The inner surface of the adjoining the inner collar 18 longitudinal portion 21 is formed by a very slim inner cone surface 23. It has an angle of inclination with respect to the longitudinal axis of the coupling body 16 of at least approximately 4.5 °. The second longitudinal portion 22 of the coupling body 16 has a circular cylindrical inner surface which is provided with a female thread 24. This is matched to the screw thread 25 of the cap screw 19. These threads are generally cylindrical pipe threads, as are common in piping systems with metal pipes.

The cap screw 19 is provided at its outer end with an external hexagon. At the inner end, the cap screw 19 has a thread-free cylindrical neck 26, whose free end face forms a flat and perpendicular to the longitudinal axis of the coupling body 16 aligned contact surface 27 for the clamping ring 20. The outer diameter of the neck 26 is dimensioned at least in the region of its end face so that it is in the operating state, d. H. at firmly tightened cap screw 19, the inner cone surface 23 of the coupling body 16 is not touched. The length of the neck 26 depends mainly on the dimensional tolerances and on the deformability of the tubes 11 and 12, which are to be coupled together by the pipe coupling 10.

The cap screw 19 is like the coupling body 16 made of metal, and also in particular made of brass.

The same applies to the clamping ring 20.

The clamping ring 20 has a circular cylindrical inside 28. On its outside, it has a very slim Au ßenkonusf pool 29. Their inclination angle with respect to the longitudinal axis of the clamping ring 20 is slightly smaller, up to 1 ° smaller than the angle of inclination of the inner cone surface 28 of the Kuppiungskörpers 16th

The end face of the clamping ring 20 with the larger cone diameter located end face serves as a contact surface 31 for the system of the cap screw 19, and that their contact surface 31 on the clamping ring 20 also aligned and aligned at least approximately at right angles to the longitudinal axis of the clamping ring. At the front end of the clamping ring 20 with the smaller cone diameter, the end face 32 is also aligned flat and at least approximately at right angles to the longitudinal axis of the clamping ring 20.

The clear width of the clamping ring 20 is at least approximately equal to the outer diameter of the pipes to be coupled 11 and

12. This clearance is referred to below as the nominal diameter of the pipe coupling 10.

The axial length of the clamping ring 20 is expediently at least approximately 0.5 times its nominal width.

As can be seen from Fig. 2, the clamping ring 20 in its central length region on a helically extending, continuous in the radial direction slot, which is referred to below as a helical slot 33. The sense of winding of the helical slot 33 is opposite to the winding sense of the nut thread 24 on the coupling body 16 and the screw thread 25 on the cap screw 19. This helical slot 33 has expediently four full turns, so that the slotted longitudinal section of the clamping ring 20 approximately divided into three adjacent full turns 34 is.

The helical slot 33 terminates in the axial direction both at the rear and at the front end of the clamping ring 20 at a certain distance from the end face of the clamping ring, so that at the rear end a length portion 35 and at the front end a length portion 36 remain unslotted. The axial extent of these unslotted length portions 35 and 36 is at least approximately 0.1 times the nominal diameter of the Kiemmringes 20. The slope of the helical slot 33 is thus at least approximately the 0.1 of ache the nominal diameter of the clamping ring 20th

The unslotted length portion 35 at the rear end of the clamping ring 20 has deviating from the remaining part of the clamping ring 20 it has a circular cylindrical outer surface which extends in the axial direction at least until the beginning of the helical slot 33, but can also go beyond slightly.

In the enlarged sectional view in Fig. 3 is compared to the normal clamping ring 20 of FIG. 2 insofar a modification included in the representation, as in the region of the unslotted front longitudinal portion 36 in a subsequent to the front end 32 section 38, the outer surface over the rest Outside cone surface 29 is offset by a certain amount of at least approximately 0.1 mm in the radius inwardly. The axial extent of this stepped portion 38 is preferably 2.0 mm. As a further part of this modification, at the end of the stepped portion 38 there is a circumferential groove 29 which, opposite the stepped portion 38, is at least approximately 0.1 mm deep and at least approximately 0.5 mm wide. The rear wall of the groove 39, which is furthest from the front end 32, adjoins the outer cone surface 29 of the clamping ring in a sharp-edged manner.

If the modified version with the stepped portion 38 and the groove 39 is selected in the clamping ring 20, make sure that the helical slot 33 in the axial direction at least approximately 0.5 mm front groove 39 ends, so that the front unslotted length portion 36 of the clamping ring 20 a not offset portion of the outer cone surface 29 remains of 0.5 mm in length, which extends between the helical slot 33 and the groove 39 over the entire circumference of the Kiemmringes 20.

In the modified embodiment of the clamping ring 20, the stepped portion 38 serves to receive a corrosion protection agent, which is applied over the stepped portion 38 also on the entire end face 32. When inserting such a Klemmrinaes in the KuDDlunasköroer 16 remains even when donning the

Cap screw 19 at least a portion of the corrosion protection layer in the region of the stepped portion 38 adhere to the outer surface, wherein the corrosion inhibitor displaced therefrom can accumulate in the groove 39. As corrosion inhibitors are polyethylene, polytetrafluoroethylene, polyamide or other thermoplastic material into consideration, the selection of which depends on which fluid or against which ingredients of the fluid, the front end of the clamping ring 20 is to be protected. The corrosion protection agent is expediently applied in pulverulent starting form in the fluidized bed process to the surface areas to be protected. As already indicated in FIG. 2 and shown more clearly in FIG. 3, the clamping ring 20 has on its circular-cylindrical inner side a number of circumferential, self-contained annular ribs 41, which are arranged in a respective normal plane to its longitudinal axis. These annular ribs 41 have a radial height of at least approximately 0.4 mm. They have an axial distance (or axial pitch) which is preferably between 1.2 and 1.4 mm with each other, wherein the smaller pitch is selected for shorter rings and smaller nominal size and the larger pitch with longer clamping rings and larger nominal diameter. The front side 32 facing the front edge 42 of the annular ribs 41 is at least approximately normal to the longitudinal axis of the clamping ring 20 aligned. The back edge 43 is at least approximately continuously rounded from the sharp annular cutting edge to the foot of the leading edge of the next annular rib 41. This is especially true for the smaller longitudinal division of the annular rib 41. For larger pitch and especially for larger nominal width, it may be appropriate to let the curvature of the trailing edge 43 expire before the next following leading edge in a circular cylindrical surface. At the rear end of the clamping ring 20, the unslotted longitudinal section 35 is conically chamfered on its inside. The angle of inclination of the chamfer 44 is about 30 ° with respect to the longitudinal axis of the clamping ring 20. The axial extent of the chamfer 44, is about 1.0 mm. By this chamfer 44, the insertion of the pipe to be coupled is facilitated in the clamping ring 20.

The pipe coupling 10 is expediently delivered already pre-assembled. In this case, 15 and 16 each a clamping ring 20 is loosely inserted in each coupling body and the cap screw 19 just screwed so far into the coupling body 16 that its front-side contact surface 27 rests against the frontal contact surface 31 of the clamping ring 20. The turns 34 of the clamping ring 20 should not yet rest against each other or, in other words, the helical slot 33 at least partially open. The pipes to be coupled 11 and 12 are inserted into the associated coupling body 15 and 16, respectively, until its end face rests against the inner collar 18 loosely. If then the cap screw 19 is screwed into the coupling body 16, initially put the turns 34 of the clamping ring 20 against each other. Thereafter, the front unslit length portion 34 of the clamping ring 20 along the inner cone surface 23 of the coupling body 16 is axially displaced. It narrows because of its small wall thickness, initially elastic, but later also additionally plastic. In accordance with this constriction, the annular ribs 41 on the inside of the longitudinal section 36 cut into the outside of the tube 12 and thereby dig into the outer layer of the GRP tube. To the extent that the axial resistance increases when pressing the front unslit length portion 36, the frictional force between the contact surface 31 on the clamping ring and the contact surface 27 on the cap screw 19 increases. As a result, the subsequent to the rear unslit length portion 35 turns 34 of the clamping ring 20 are increasingly taken from front to back, the turns narrow and present on its inner side annular ribs 41 also increasingly in the outside of the GRP pipe 12th dig. Once this process is completed, the end portion of the tube 12 with the pipe coupling 10 is tightly and firmly connected.

The previous explanations were focused on the connection of GRP pipes, which can be produced with relatively tight tolerances and which have a relatively low elastic strain. Tubes that are made exclusively of a thermoplastic material, which therefore lacks a Glasfaserarmierung have, first, larger tolerances and secondly, a greater elongation.

For connecting such pipes, it may be appropriate to use the pipe clamp connection in a modified embodiment. In her, the inclination angle of the inner cone surface on the clutch housing is larger, up to 10 °, so that the inner cone surface on the coupling body, but also the length of the nut thread must not be carried out excessively long. Due to the greater inclination angle of the two conical surfaces, it may also be appropriate to use a fine thread instead of the normal pipe thread between the coupling body and the cap screw, so that the translation between the peripheral force on the hexagon and its feed force is increased in the cap screw to the higher radial force Tighten narrowing of the front unslit length of the clamping ring again.

Another modification of the pipe clamp connection may be that both the coupling body, as well as the clamping ring are used in fiberglass design. This may be convenient, if not necessary, if the fluid passed through the piping system does not allow the use of metals or suggests the transition to plastic particles. In GRP composites, the inner wall coating exposed to the fluid can be adapted within wide limits to the requirements of the fluid, without the remaining layers of the composite material having to be changed to any appreciable extent.

The transition to GRP design may be indicated even if, especially with a higher number of joints and / or fittings in the piping system, the total weight of the piping system or even just the "weight" of the pipe clamp connections is very high or off other reasons, the reduction of the metal content in the pipe system is desired or necessary.

In the GRP design of the pipe clamp, it is of great advantage if the glass fiber reinforcement is at least more or better aligned in the circumferential direction on the clamping ring in the region of the annular ribs. In addition, it is expedient to choose the glass fiber content greater than in the material of the remaining parts of the clamping ring in the material of the annular ribs. This gives the ring ribs a higher dimensional stability, allowing them, despite the fiberglass construction, to extend far enough into the outside, e.g. in the outer layer to dig the pipes to be coupled and to seal both good and secure.

From Figure 4 is a pipe clamp connection 45 can be seen as a further embodiment in which the coupling housing 46 is modified relative to the clutch housing 16 of the basic version in part.

At the collar 47, more precisely at its flat end face 48, first includes a circular cylindrical surface 49 and thereon an inner cone surface 50 at. The circular cylindrical surface 49 has a certain axial extent, which is expediently not smaller than 2 mm. Their clear width is at least approximately equal to or slightly larger than the nominal diameter of the pipe clamp connection

45 or the outer diameter of the tube 12. This circular cylindrical surface 49 serves as a guide surface for the front end of the tube 12, in particular when it is inserted into the already pre-assembled pipe clamp connection 45. This ensures that the tube 12 is guided centrally at its front end to the longitudinal axis of the coupling housing 46. The inner cone surface 50 serves as an insertion cone for the front end of the tube 12. The inclination angle of this inner cone surface 50 is therefore preferably in the angular range of 30 ° to 45 °. At this insertion cone closes at the pipe clamp 45, the inner cone surface 51 for the clamping ring 20, which is designed the same as the corresponding inner cone surface 23 on the clutch housing 16 (Fig. 1). The other parts of the coupling housing 46, as well as the cap screw 19, equal to the corresponding parts of the embodiment of FIG. 1st

From Fig. 5, a clamping ring 53 can be seen, which is modified relative to the clamping ring 52. In the slotted by the helical slot 53 mean length portion 54 of the clamping ring 52 takes the radial depth of the annular recesses 55 between two annular ribs 76 from the front end of the length portion 54 to its rear end from a maximum value to zero from. The maximum value of the depth of the recesses 55 is at least approximately equal to the radial depth of the corresponding recesses 57 in the front unslit length portion 58 of the clamping ring 52. Since the radial depth of the recesses 55 at the rear end of the slotted longitudinal portion 54 has reached zero, are in the rear unslit longitudinal section 59 of the clamping ring 52 on its inside no recesses and thus no ring ribs more present. This inner side therefore forms a smooth circular cylinder surface 60.

From Fig. 6 and 7, a pipe clamp connection 61 can be seen as a further embodiment. In the pipe clamp joint 61 includes on the inside of the coupling body 62 at the outer end of the inner cone surface 63 for the clamping ring 20, a circular cylindrical surface 34 whose inside diameter is greater than the outer diameter of the rear end of the clamping ring 20, which is greater than the outer diameter of the unslotted rear longitudinal section 35 of the clamping ring 20 is. The outer diameter of this circular cylindrical surface 64 is matched to the inner cone surface 63 so that the transition point 65 is located between the inner cone surface 63 and the circular cylindrical surface 64 within that length portion of the coupling body 62, the clamping ring 20 assumes after tightening the cap screw 19 (Fig.7) , The axial extent of the circular cylindrical surface 64, starting from the transition point 65, so dimensioned that it still protrudes beyond the rear end of the clamping ring 20 in the clamping ring 20 inserted in untensioned (Figure 6). Between the rear end face 31 of the clamping ring 20 and the front end face 27 of the cap screw 19, a Stemming 66 is inserted or inserted. The clear width of Stemming ring 66 is not smaller than the nominal diameter of the clamping ring 20, better even not smaller than the inside diameter of the cap screw 19. The Stemming ring 66 has two end surfaces 67 and 68 which are parallel to each other. The Stemming ring 66 is conically shaped, so that its two end faces 67 and 68 have the shape of the lateral surface of a truncated cone. The inclination of the surface line of the two frusto-conical end faces 67 and 68 is in the range of 60 ° to 75 ° and is preferably about 68 °. The peripheral surface 69 of the Stemming ring 66 is formed in the untensioned rest state of the stemming ring 66 (FIG. 6) a is circular cylindrical surface with respect to the central axis of the stemming ring 66. In particular, the peripheral edge 70 between the peripheral surface 69 and the inner end face 68 is sharp-edged.

When tightening the pipe clamp 61 of the stub ring 66 is first printed by the cap screw 19 against the clamping ring 20 and pushed together with this a certain distance in the coupling body 62 (Fig. 7). Once the clamping ring 20 has narrowed at its front end, not shown, that he clamps the tube 12 tight and tight and therefore at the rear end of the clamping ring 20 of the resistance to displacement increases to a higher value, the Stemming ring 66 between the rear end face 31 of the clamping ring 20 and the front end face 27 of the cap screw

19 flattened (Fig.7), wherein the peripheral surface 69 is pressed outwards and its peripheral edge 70 digs into the circular cylindrical surface 64 of the coupling body 62. As a result, the stiffening ring 66 is caulked to a certain extent with the coupling body 62. Even if the cap screw 19 would loosen once, the locking ring 66 would ensure that the clamping ring 20 can not expand in the axial direction can., Because the axial force emanating from him ensures that the Stemming 66 even more in the circular cylindrical surface 64 of the coupling body 62 digs.

The clamp connection 61 is suitable for such pipe connections into consideration, which must not be solved after their installation and in which even more is required that a safeguard against unintentional release of the pipe clamp connection, dodge the reasons whatsoever, is present.

From Fig. 8, a pipe coupling 71 can be seen, which is compared to the previously described pipe couplings, such as the pipe couplings of Fig. 1 and Fig.4, modified with regard to their two pipe clamp connections 72 and 73 not with cap screws but with one each Union nut 74 are equipped. As a result missing on the coupling housing 75 at both ends of those longitudinal sections which have the internal thread for the cap screws in the coupling housing 46. Apart from that, the clutch housing 75 in its interior in the region of the clamping ring

20 are formed in much the same manner as the clutch housing 46 (FIG. 4), the explanation of which is therefore incorporated herein by reference.

On the coupling housing 75, the inner cone surface 76 for the clamping ring 20 has an axial length which is shorter than the inner cone surface 51 on the clutch housing 46. The inner cone surface 76 is so short that, in the operating position or clamping position of the clamping ring 20 (FIG. 8), its rear unslotted longitudinal portion 35 protrudes partially out of the coupling housing 75.

Approximately in the same La η gene section as the inner cone surface 76, the external thread 77 is arranged for the union nuts 74 on the outside of the coupling housing 75. Between the two length sections with the internal thread 77 for the two union nuts 74, the coupling housing 75 on a length portion 78 which is provided with key surfaces 79 which are formed as hexagonal surfaces or as octagonal surfaces.

The union nut 74 has an annular collar 81, whose clear width is not smaller than the nominal diameter of the pipe 12 to be coupled and expediently even slightly larger. At the inner end face of the collar 81 includes a collar-shaped extension 32 in the axial direction. The extension 82 has the same inside width as the collar 81. The outer diameter of the extension 82 is not greater than the outer diameter of the rear unslit length portion 35 of the clamping ring 20. The axial length of the extension 82 is generally between 0.5 mm and 2 , 0 mm. The end face of the collar-shaped extension 82 forms the contact surface 83 for the clamping ring 20. By the collar-shaped extension 82, a larger axial actuation path for the nut 74 is achieved, because if necessary, the extension 82 can be moved into the coupling housing 75, so that the union nut 74 then still on the rear contact surface

of the clamping ring 20 can exert an axial force when the rear longitudinal section 35 of the clamping ring 20 is already completely immersed in the coupling housing 75. This case could then occur once, if the manufacturing tolerances of all interacting parts, in particular those of the diameter dimensions of the inner cone surface 76, the clamping ring 20 and the tube 12, meet in an unfavorable manner.

From Figure 9 is a further modification of the pipe clamp connection can be seen. The pipe coupling 85 is designed externally equal to the pipe coupling 71 (FIG. 8). Their two pipe clamp connections 86 and 87 also each have a union nut 88, which are designed the same as the union nut 74. However, the clutch housing 89 is modified in the interior, in the middle longitudinal section, relative to the clutch housing 75. This is in view of the fact that the pipe coupling 85 for the coupling of plastic pipes 91 and 92 is determined, which are made of a thermoplastic material. Due to the lower strength of their material, such tubes have a considerably greater wall thickness than is the case with the GFRP tubes 11 and 12.

The clutch housing 89 has in its central longitudinal section 93 on the inside of a collar 94 whose clear width not smaller than the inside diameter of the two plastic tubes 91 and 92. At each end face of the collar 94 has an outer ring area an at least approximately flat face 95th which is aligned normal to the longitudinal axis of the clutch housing 89. An inner extension 96 is formed on both sides of the inner ring area adjoining inwardly. The inner circumferential surface 97 of the extensions 96 is at least approximately designed as a circular cylindrical surface whose inside diameter is equal to the clear width of the collar 94. The outer peripheral surface 98 is formed as a lateral surface of a truncated cone whose generatrices relative to the longitudinal axis of the coupling housing 89 have an inclination angle between 20 ° and 45 °, wherein in FIG. 9, an inclination angle of 30 ° is shown.

Each of the two tubes 91 and 92 is provided at the end cooperating with the pipe coupling 85 on its inside with a recess 99 which is matched to the axial extension 96 and which accordingly appears as a lateral surface of a hollow truncated cone.

As can be seen from Figure 9, the extension 96 at the transition point to the collar 94, d. H. at its thickest point, an outside diameter smaller than a Is is the outside diameter of the tubes 91 and 92. As a result, remains at the front side of the tubes 91 and 92 outside the frusto-conical recess 99 is still a flat annular end face 100 are. Thus, the recess 99 can cooperate with the extension 96 on the coupling housing 89 in the correct manner on the tube 91 or 92 and while the extension 96 can act as a support collar for the pipe in question, it is expedient that during manufacture of the recess 99, for example by means of a tapered Senkwerkzeuges, at the same time the end face 100 is processed. This ensures that the end face 100 is smooth and flat and that no irregularities have remained from the sawing of the pipe, which prevent the pipe end can be pushed to the abutment 96 of its recess 99 on the extension 96 to the collar 94. The easiest way to achieve this is that the conical countersinking tool is combined with a flat counterbore and that in a single operation, the recess 99 is made and at the same time the end face 100 is processed. It is important to ensure that the recess 99 is not deeper, a is the extension 96 is long, so that upon insertion of the tube, the recess 99 is already seated on the extension 96 before the StirnflächeiOO can abut the collar 94.

In the embodiment of the pipe clamp connections according to FIG. 9, the pipe end is centered on the inside by the conical extension 96. Therefore, the outer guide surface is omitted, which is formed in the embodiment of FIG. 4 by the circular cylindrical surface 49, which precedes the inner cone surface 50. In so far corresponds to the embodiment of Figure 9 of the embodiment of FIG. 1st

The axial extension on the collar 94 may instead of the frusto-conical peripheral surface 98 also have a circular cylindrical peripheral surface, but expediently the outer edge is chamfered on the free end face of the extension, so that a kind of insertion cone is formed. According to the cylindrical shape of the extension then the recess must be formed on the inside of the tubes circular cylindrical. However, the cylindrical shape of the two contact surfaces is more sensitive to manufacturing tolerances of the diameter dimensions.

Claims (19)

1. Pipe clamp connection with the following elements: - A hollow coupling body has for the system of a clamping ring a Innenkonusf laugh on the large diameter of the free end face of the coupling body is facing at the mouth of its cavity, - The coupling body has, in connection with its free end face, a central thread arranged centrally to the inner cone surface for a cap screw or an external thread for a cap nut, the cap screw or cap nut has an end-face contact surface for the clamping ring, - The clamping ring has on its kreiszylindrischeh inside a number of circumferential, self-contained annular ribs, which are arranged in a respective normal plane to its longitudinal axis, the ring ribs have a sharp edge on the inside edge, - The clamping ring has on its outer side an outer cone surface which is at least approximately matched to the inner cone surface of the coupling body, characterized by the features: the inner cone surface (23) on the coupling body (16) and the outer cone surface (29) on the clamping ring (20) have a very small angle of inclination with respect to the longitudinal axis, - On the clamping ring (20) is the contact surface (31) for the cap screw (19) or union nut and on the cap screw (.19) or union nut, the contact surface (27) for the clamping ring (20) is at least approximately flat and normal to Longitudinal axis of the clamping ring (20) aligned, - The clamping ring (20) has a helically extending, radially continuous slot (33) (helical slot), in the axial direction at the front end of the clamping ring (20) with the smaller cone diameter at a certain distance from the end face (32) of the clamping ring (20) ends, - The winding sense of the Wendeischlitzes (33) is opposite to the winding sense of the thread between the coupling body (16) and the cap screw (19) or union nut. 2. Pipe clamp connection according to claim 1, characterized by the features: - The clamping ring (20) also has at its rear end with the larger cone diameter a length portion (35) of a certain length, which is not slotted, - Preferably, this unslotted rear longitudinal portion (35) of the clamping ring (20) has a circular cylindrical outer surface (37). 3. Pipe clamp according to claim 1 and / or claim 2, characterized by the features: - The inner cone surface (23) of the coupling body (16) has an inclination angle relative to its longitudinal axis which is at least approximately 4.5 °, - The outer cone surface (29) of the clamping ring (20) has a tilt angle! relative to its longitudinal axis which is up to 1 ° smaller than the inclination angle of the inner cone surface (23) of the coupling body (16). 4. pipe clamp connection according to claim 1 to 3, characterized by the features: - The unslotted length portion (36) at the front end of the clamping ring (20) has an axial extent which is at least equal to the axial distance between two adjacent annular ribs (41) on the inside of the clamping ring (20), - Preferably, the axial extent of the unslotted length portion (36) at the front end of the clamping ring (20) at least approximately 0.1 times the clear width (nominal diameter) of the clamping ring (20) (nominal diameter) and at the same time the outer diameter of the tube (12). 5. pipe clamp connection according to claim 1 to 3, characterized by the features: - The annular ribs (41) have a radial height of at least approximately 0.4mm, the annular ribs (41) preferably have an axial distance between 1.2 and 1.4 mm, - Preferably, the front end side (32) facing the front edge (42) of the annular ribs (41) is aligned normal to the longitudinal axis of the clamping ring (20) and the trailing edge (43) from the sharp edge of the annular rib (41) to the bottom of the leading edge (42) of the subsequent annular rib (41) in the longitudinal section at least approximately continuously concave rounded. 6. pipe clamp connection according to claim 1 to 4, characterized by the feature: - The unslotted length portion (35) at the rear end of the clamping ring (20) has an axial extent which is at least approximately 0.1 times the nominal diameter of the clamping ring (20). 7. pipe clamp connection according to claim 1 to 5, characterized by the features: the helical slot (33) has 4 full turns, - The slope of the helical slot (33) is preferably 0.1 times the nominal diameter. 8. pipe clamp connection according to claim 1 to 6, characterized by the feature: - The coupling body (16) and the clamping ring (20) are made of a metal whose strength is higher than that of the material of the outside of the pipe to be coupled (12) or at least the outside thereof. 9. pipe clamp connection according to claim 7, characterized by the features: - The clamping ring (20) in the region of the unslotted front longitudinal portion (36) in a to the front end side (32) adjoining portion (38) of its outer cone surface (29) parallel to this offset by a certain amount inwardly, the undersize of this stepped portion (38) with respect to the remaining outer cone surface (29) is preferably 0.1 mm in the radius, the axial extent of the stepped portion (38) is preferably 2.0 mm, Preferably, the recessed portion (38) is followed by a circumferential groove (39) which is preferably 0.1 mm deep in relation to the stepped portion (38) and which is preferably 0.5 mm wide. - The rear wall of the groove (39) includes sharp edges on the outer cone surface (29) of the clamping ring (20), - The front end face (32) of the clamping ring (20) is complete and the stepped portion (38) is coated to approximately the groove (39) out with a corrosion inhibitor. - The helical slot (33) terminates at the front end of the clamping ring (20) at least approximately 0.5 mm in front of the groove (39). 10. Pipe clamp connection according to claim 8, characterized by the features: the corrosion inhibitor consists of polyethylene, polytetrafluoroethylene, polyamide or another thermoplastic, - The corrosion inhibitor is preferably applied in powdered starting form in the vortexing process on the clamping ring (20). 11. Pipe clamp according to claim 1 to 9, characterized by the feature: - The clamping ring and preferably also the coupling body are made of plastic, in particular of glass fiber reinforced plastic (GRP). 12. Pipe clamp connection according to claim 11 made of GFK, characterized by the features: on the clamping ring, the glass fiber reinforcement is aligned in the circumferential direction in the region of the annular ribs, - Preferably, in the material of the annular ribs of the glass fiber content is greater than in the material of the remaining parts of the clamping ring. 13. pipe clamp connection according to claim 1 to 12, characterized by the features: - The clamping ring (20) is chamfered at its rear end on the inside, - The chamfer (44) preferably has an inclination angle of .30 ° relative to the longitudinal axis of the clamping ring (20) and preferably an axial extent of 1.0mm. 14. pipe clamp connection according to claim 1 to 13, characterized by the features: - The clamping ring (20) is chamfered at its front end on the outside, - The chamfer (45) preferably has an angle of inclination of 30 ° relative to the longitudinal axis of the clamping ring (20) and preferably an axial extent of 0.5 mm. 15. pipe clamp connection according to claim 1 to 14, characterized by the features: - On the coupling body (62) adjoins the inner cone surface (63) for the clamping ring (20) on a circular cylindrical surface (64) whose inside diameter is greater than the outer diameter of the rear end of the clamping ring (20), - The transition parts (65) between the inner cone surface (63) and the circular cylindrical surface (64) is located within the longitudinal portion of the Kuppiungskörpers (62), the clamping ring (20) after tightening the cap screw (19) or union nut occupies - between the rear end surface (31) of the clamping ring (20) and the front contact surface (27) of the cap screw (19) or union nut ei η Stemm ring (66) is inserted whose inside diameter not smaller than the nominal diameter of the clamping ring (20) is and its outer diameter is at least approximately equal to the clear width of the circular cylindrical surface (64) on the coupling body (62) in the untensioned rest state, - The two end faces (67, 68) of the Stemmringes (66) parallel to each other and have the shape of the lateral surface of a truncated cone, - The inclination of the generatrices of the two frusto-conical end faces (67; 68) of the Stemmringes (66) relative to the central axis of the Stemmringes (66) is preferably in the range of 60 ° -75 °. - The peripheral surface (69) of the Stemmringes (66) is formed in the untensioned resting state as circular cylindrical surface and at least the peripheral edge (70) at the transition to the inner end face (68) of the Stemmringes (66) formed sharp-edged. 16. pipe clamp connection according to claim 1 to 15, characterized by the feature: - In the slotted longitudinal portion (54) of the clamping ring (52) increases the radial depth of the recesses (55) between the annular ribs (56) from the maximum size at the front end of the slotted longitudinal section (54) to zero at the rear end of the slotted longitudinal section (54 ). 17. pipe clamp connection according to claim 1 to 16 with a union nut, characterized by the features: - On the union nut (), the contact surface () for the clamping ring () through the end face of a collar-shaped extension () is formed, which connects to the annular collar () of the union nut () in the axial direction and in the direction of the internal thread () of Union nut () extends, - The annular extension has • a clear width that is not smaller than the clear width of the rear end of the clamping ring (), and • an outer diameter no larger than the outer diameter of the rear end of the clamping ring (). 18. Pipe clamp according to claim 1 to 17, characterized by the features: - The coupling body (46) has on its inside a collar (47) whose inside diameter is not smaller than the inside diameter of the tube (12), - The tube (12) facing the end face of the collar (47) is at least approximately flat and aligned normal to the longitudinal axis of the coupling body (46), - Preferably, the inside of the coupling body (46) following the collar (47) on a circular cylindrical surface (49), which has a certain axial extent and whose inside diameter is at least approximately equal to or slightly larger than the outer diameter of the tube (12) . - An inner cone surface (50) adjoins the circular cylindrical surface (49), the angle of inclination relative to the longitudinal axis of the coupling body (46) is preferably in the angular range of 30 ° ^ 5 °, - On the inner cone surface (50) closes the inner cone surface (51) for the clamping ring (20). 19. Pipe clamp according to claim 1 to 17, characterized by the features: - The coupling housing (89) has on its inside a collar (94) whose inside diameter is not smaller than the inside diameter of the tube (91; 92), from the end face of the collar (94) facing the tube (91; 92), an outer annular region has at least approximately the shape of a flat end face (95) oriented normal to the longitudinal axis of the coupling housing (89), - An axial extension (96) is arranged or formed on the inwardly adjacent inner annular region of the collar (94), ο whose inner peripheral surface (97) is at least approximately formed as a circular cylindrical surface whose inside diameter is not smaller than the inside diameter of the tube (91, 92), and • whose outer peripheral surface (98) is formed either as a circular cylindrical surface or, preferably, as a lateral surface of a truncated cone whose generatrices have an angle of inclination between 20 ° and 45 ° with respect to the longitudinal axis of the coupling housing (89), - The cooperating with the coupling housing (89) end of the tube (91, 92) is provided on its inside with a on the axial extension (96) on the coupling housing (89) tuned recess (99). 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