Fitting with a fixing element and method for creating a leak-tight connection
The invention relates to a fitting for creating a leak-tight connection with a workpiece, in particular with a pipe, having at least one pressing area, wherein at least one sealing element and at least one fixing element are arranged in the pressing area, wherein the fixing element has at least one cutting element made of a hard material, in particular metal. The invention further relates to a method for creating a leak-tight connection between a fitting and a workpiece, in particular a pipe, in which at least one sealing element and at least one fixing element are arranged in a pressing area. The invention further relates to a leak-tight connection between a fitting and a workpiece.
Fittings of the type mentioned above are used in piping technology and steel construction in the prior art, among other things, to create a leak-tight connection, in particular to guide fluids or gases in pipes and their connections. Here, the fitting is pressed together with a workpiece, for example a pipe or an armature, resulting in a leak-tight, permanent connection. The connection can furthermore be indissoluble, in other words not able to be removed from the workpiece or the fitting without destroying them.
A generic fitting has at least one sealing element and one fixing element. The sealing of the connection to be created is achieved by means of the sealing element, which for example is made of an elastic material and placed with a leak-tight fit on the fitting and the workpiece. The fixing element is used for the mechanical fixing of the connection and prevents an undesired loosening of the connection. The fixing element is generally made of a hard, non-elastic material and creates a friction fit or a form fit with the workpierc, in particular by being pressed or cut into the workpiece. A design of a fitting of this type is also particularly suitable for large pipe diameters.

Fittings are known from EP 0 922 896 A1 and DE 102 07 201 A1 which have cutting elements and sealing elements which are arranged in particular in two different sections on an inner circumference of the fitting.
Furthermore, EP 1 593 899 A1 and WO 2010/089188 A1 describe fittings in which the cutting element and scaling element arc arranged together in a pressing section. Here, the cutting element and sealing element are separated by an intermediate separation ring.
EP 1 593 898 Al further discloses a sealing element for a fitting made of an elastic material, wherein cutting elements are embedded within the sealing element.
The object of the present invention is to provide a fitting and a method for creating a leak-tight connection with a workpiece that further facilitates the construction and use of the fitting and simultaneously improves the connection to be created. A leak-tight connection between a fitting according to the invention and a workpiece is also described.
The above mentioned object is achieved according to a first teaching relating to a fitting in that the fixing element has at least one holding element which is made at least in part of a plastics material and that the holding element has at least one cutting element.
The fact that the fixing element has at least one cutting element made of a hard material, in particular metal, and at least one holding element which is made at least in part of a plastics material means that at least one cutting element can be arranged according to the requirements of pressing. The at least one cutting element or cutting elements are held by the holding element, as a result of which the cutting elements can be arranged freely in the pressing area of the fitting, without the cutting elements having to be designed such that they remain in a certain position on their own. The

fixing element of the fitting has a larger freedom of design and a greater degree of flexibility of use than conventional fittings.
The holding element is made at least in part of a plastics materials. The use of a plastics material at least as part of the fixing element means that production costs are lowered compared to a fixing element made entirely from a hard material, in particular metal, as the material costs are less. Individual, smaller cutting elements with a simple structure made of a hard material, in particular metal, can be used, which are for example distributed along the circumference of a circular cross-section of a holding element The at least one cutting element is then held in particular by a ring-shaped holding element. In contrast to fixing elements made completely out of a hard material, in particular metal, the plastics material of the holding element is easier to shape and to process, which in turn lowers the production costs of the fitting. The holding element is preferably made completely from a plastics material.
In addition to this, the design options for the fixing element are also improved. The plastics material used for the holding element is preferably a hard plastics material which deforms only to an insignificant extent in response to the pressing forces that occur during pressing. The holding element can therefore be designed such that the transfer of the pressing forces to the at least one cutting element are promoted and supported by the holding element. This can result in the pressing force exerted by the at least one cutting element being increased or set in a targeted manner, leading to better pressing by the at least one cutting element into the material of the workpiece to be pressed and therefore overall to a better pressing result.
The holding element can therefore hold the at least one cutting element during pressing in an advantageous position and support the pressing or cutting of the at least one cutting element into the workpiece.
In an embodiment of the fitting, the holding clement and the at least one cutting element are connected to one another. Connecting the holding element and the cutting

element facilitates the handling and production of the fitting as fewer parts need to be taken into account. In addition to this, combining the holding element and the cutting
element is advantageous for supporting the cutting process of the cutting element by means of the holding element, particularly if a connection of this type does not have a clearance. A connection between the holding element and the at least one cutting element can be made by means of friction fit, a form fit and/or a material fit.
For example, the holding element can be designed in a ring shape and at least one cutting element is combined with the holding element using friction along the circumference. This can result in the cutting elements being designed in a particularly simple manner, for example from bent sheet metal. Cutting elements of this type can be designed in a clamp-shaped or U-shaped manner and extend in a radial or axial direction relative to a ring-shaped holding element.
For example, a ring-shaped holding element can have at least one recess along its circumference in which at least one cutting element is arranged. This creates better friction between the elements and a ring-shaped fixing element with an essentially uniform external and internal circumference is provided. The recesses can also have a profile resulting in a form fit with the cutting elements.
Holding elements and cutting elements can also be connected by means of a material fit, for example by adhesion or welding. The at least one cutting element can be connected to the holding element in a material-bonded manner by means of insert moulding or extrusion of the plastics material of the holding element.
In particular, the fixing element is designed as one-piece and has friction fit, a form fit or a material fit between the at least one cutting element and the holding element. This further reduces the number of parts in the fitting, thereby simplifying production
and handling.

In a further embodiment of the fitting, the fixing element is in direct contact with the seating element. Direct contact between the sealing element and a cutting element can be problematic as the sealing element can be mechanically damaged during pressing and the connection may potentially even cease to be leak tight. The approach of arranging a separation ring made of plastics material between the sealing element and the cutting element is therefore often used.
In the case of fixing elements which have a holding element, the use of a separation ring is not required. In particular, the sealing element is in direct contact with the holding element, wherein the at least one cutting element is held at a distance from the sealing element. The holding element can therefore carry out the same function as the separation ring. The section of the holding element which comes into contact with the sealing ring is preferably made of plastics material. Any impairment of the sealing element by the fixing element during pressing can therefore be avoided in a simple manner.
In a further embodiment of the fitting, however, the at least one cutting element has a ring-shaped element which comes into direct contact with the sealing element. Contact between the sealing element and a ring-shaped section of the at least one cutting element can improve the leak tightness of the connection to be created.
In a further embodiment of the fitting at least one additional separation element is provided which is arranged between the sealing element and the fixing element. The separation ring can in particular protect the sealing element from any impairment during pressing and further contribute to the leak tightness.
In a further embodiment of the fitting, the fixing element is configured in a ring shape and has a plurality of cutting elements which are arranged distributed along the circumference of the fixing element. As already described, the material costs can be reduced using the holding element and at the same time the pressing outcome can be improved. In particular pipe-shaped workpieces along the circumference can be

encircled by a ring-shaped fixing element. Several cutting elements arranged distributed along the circumference can be used for secure mechanical fixing of the connection.
In particular, the cutting elements are distributed at equal distances along the circumference. The cutting elements can also be arranged in a symmetrical manner, for example in a mirror-symmetrical manner.
Furthermore at least one ring-shaped cutting element can be provided, wherein the cutting element has individual cutting edges distributed along the circumference. A corresponding holding element can supplement the ring-shaped cutting element such that at least one section of the outer circumference of the fixing element, not including the cutting edges, is essentially cylindrical.
In a further embodiment of the fitting, the holding element is made up at least in part of polybutylene terephthalate (PBT), polyoxymethylene (POM), polyamide (PA), polyethylene terephthalate (PET) or polysulfone. In general, thermoplastic plastics materials with good strength characteristics and high resistance to temperature can be used in both reinforced and non-reinforced configuration. These plastics materials are advantageous in production and processing. At the same time, the materials are hard enough not to deform substantially under the conditions of pressing.
With harder materials in particular, the holding element can also transfer pressing forces. In a further embodiment of the fitting the holding element is configured to transfer a pressing force acting on the pressing section to the at least one cutting element when the fitting is being pressed. In particular, a pressing force exerted on the fitting acts initially on the holding element. The at least one cutting element is held by the holding element such that at least part of the pressing force is transferred to the at least one cutting element, which in turn is pressed into the material of the workpiece. By means of the flow of forces of the pressing force from the fitting via the

holding element to the at least one cutting element, by means of the design of the holding element the pressing outcome can be influenced in a targeted manner.
In particular, the force can be diverted on the holding element. For example, a pressing force acting in a radial direction on a fitting can be converted into a force which acts in an axial direction on the at least one cutting element so that the at least one cutting element is pressed in a partially axial direction into the workpiece.
In a further embodiment of the fitting there is a contact area for contact with a workpiece. The use of a contact area, which preferably is not or is only partly pressed, can give the connection a greater level of stability. In particular, the contact area can hold the workpiece before pressing.
In the case of pipe-shaped workpieces, the inner diameter of the contact area can correspond to the outer diameter of the workpiece or the outer diameter of the contact area can correspond to the inner diameter of the workpiece.
In addition to this, the pressing area on the side facing away from the contact area can have at least one stop. A stop of this type can in particular be used to delimit the pressing area and hold the sealing element and optionally the fixing element in their positions before pressing. The end of the fitting can for example be beaded for the provision of a stop. A beading of this type can be along the entire circumference or in segments.
The stop can also be formed by the holding element. This facilitates the production of the fitting. For example, beading the end of the fitting can be omitted.
The above mentioned object is achieved according to a further teaching relating to a method for the creation of a leak-tight connection between a fitting and a workpiece, in particular a pipe, wherein the fixing element has at least one cutting element made of a hard material, in particular metal, and at least one holding element, which is made

at least in part from a plastics material, and wherein the at least one cutting element is held by the holding element, wherein a workpiece is brought into abutment to the fitting, wherein the fitting is pressed at least in the pressing area, wherein the sealing element is pressed between the fitting and the workpiece and wherein the at least one cutting element is pressed into the material of the workpiece.
In particular, the fitting is configured in the same manner as the above mentioned fitting. As described above, the at least one cutting element or cutting elements can be precisely positioned according to the requirements of pressing by means of a holding element and arranged in the fitting. The fixing element of the fitting has a larger freedom of design and a greater degree of flexibility of use than conventional fittings.
The plastics material used for the holding element is preferably a hard plastics material which deforms only to an insignificant extent in response to the pressing forces that occur during pressing. The holding element can therefore be designed such that the transfer of the pressing forces to the at least one cutting element are promoted and supported by the holding element. This can result in the pressing force exerted by the at least one cutting element being increased or set, leading to better pressing or cutting by the at least one cutting element into the material of the workpieces to be pressed and therefore to a better pressing result.
In an embodiment of the method the at least one cutting element is also pressed into the material of the fitting. This results in improved fixing of the connection as the at least one cutting element combines the workpiece and the fitting on both sides by means of a form lit.
It is conceivable that some of the cutting elements will cut into the workpiece and other cutting elements will cut into the fitting. Since the individual cutting elements are held against one another by the holding element, this results in a better connection.

In a further embodiment of the method during pressing, a pressing force exerted on the fitting is transferred to the at least one cutting element by means of the holding element. In particular, a pressing force exerted on the fitting acts initially on the holding element. The cutting elements are held by the holding element such that at least part of the pressing force is transferred to the cutting elements, which in turn can cut at least into the material of the workpiece.
In particular, the force can be diverted on the holding element. For example, a pressing force acting in a radial direction on a fitting can be converted into a force which acts in an axial direction on the at least one cutting element so that the at least one cutting element is pressed or cut in a partially axial direction into the workpiece.
In a further embodiment of the method, a friction fit and/or a form fit is achieved between the holding element and the workpiece. The holding element can be pressed against the workpiece by means of the pressing of the fitting and further strengthen the connection by means of friction. A form fit between the holding element and the workpiece is also conceivable, for example by means of a profiling on the holding element and the workpiece.
The above mentioned object is achieved according to a further teaching relating to a leak-tight connection between a fitting and a workpiece, in particular a pipe, wherein the leak-tight connection is created in particular by means of a method described above with a fitting described above, wherein the sealing element is attached in a leak-tight manner between the fitting and the workpiece and wherein the at least one cutting element is pressed into the material of the workpiece. In an embodiment of the leak-tight connection the at least one cutting element is also pressed into the material of the fitting.
Reference is also made to the above embodiments of the fitting for information on further embodiments and advantages of the method and the leak-tight connection. The invention is described below in greater detail by means of drawings in which:

Fig. la is a lateral view of a first embodiment of a fitting having a pipe, in a not
pressed state,
Fig. lb is a lateral view of the first embodiment of a fitting having a pipe, in a
pressed state,
Fig. 2 is a perspective view of an embodiment of a holding element,
Figs. 3a, b, c are embodiments of cutting elements,
Figs. 4a, b arc perspective views of embodiments of fixing elements,
Figs. 5a, b are perspective views of further embodiments of cutting elements,
Fig. 6a is a perspective view of an embodiment of a fixing element with the
cutting element from Fig. 5b,
Fig 6b is a second embodiment of a fitting having the fixing element from
Fig, 6a and a pipe,
Fig. 7a is a lateral view of a third embodiment of a fitting having a pipe,
Fig. 7b is a perspective view of the fixing element from Fig. 7at
Fig. 8a is a lateral view of a fourth embodiment of a fitting with a pipe,
Fig. 8b is a perspective view of the fixing element from Fig. 8a,
Figs. 9a, b are perspective views of further embodiments of cutting elements,

Fig. 10 is a perspective view of a further embodiment of a fixing element,
Fig. 11 is a perspective view of a further embodiment of a fixing element,
Fig. 12 is a perspective view of a further embodiment of a fixing element and
Figs. 13a, b show a system with an embodiment of a fitting and a pressing tool.
Fig. la is a lateral view of a first embodiment of a fitting 2 having a pipe 4 as a workpiece, in a not pressed state. The fitting 2 is pipe-shaped and has a pressing area 6 and a contact area 8. The contact area 8 has an internal diameter which approximately corresponds to the external diameter of the pipe 4 such that the pipe 4 can be held in the contact area 8 by means of abutment,
A sealing element 10 and a fixing element 12 are arranged in the pressing section 6 of the fitting 2. The fixing element 12 has metallic cutting elements 14 which are held by a holding element 16 made of a plastics material.
Pressing of the fitting 2 using the pipe 4 can now occur by means of a pressing tool which is not shown in Fig. 1. An embodiment of a suitable pressing tool is explained below in connection with Figs. 13a, b. In particular, the pressing area 6 on the outer circumference is impacted by a pressing force acting in a radial, inwards direction and is deformed. This results in a pressing force acting on the sealing element 10 and the fixing element 12.
Fig. lb is a lateral view of the first embodiment of a fitting 2 having a pipe 4, in a pressed state. The sealing element 10, made of an elastic material and for example being in the shape of an O-ring, is deformed such that it is attached in a leak-tight manner to the pressing area 6 and the pipe 4. The connection created can be guided sealed by means of the sealing element 10 against the liquids and/or gases which are guided through the pipe 4. Mechanical fixing and in particular an insolubility of the

connection is achieved using the fixing element 12. The cutting elements 14 are held
by the holding element 16. During pressing, the pressing forces act on the cutting elements 14 such that the cutting elements cut into the material of the pipe 4. With this, the connection is mechanically fixed.
Fig. 2 is a perspective view of an embodiment of a holding element 16, The holding element 16 is configured in a ring shape and has slits 18, 20 along the circumference. The slits 18, 20 enable slight deformation of the holding element 16 along the circumference, as a result of which pressing forces can be transferred onto the cutting elements held by the holding element 16 in the circumference side direction. The slits 18,20 can also be used as an indicator for the completeness of pressing, by means of the slits 18, 20 for example being visible from the outside. The width of the slits 18, 20 gives an indication of the circumference of the holding element 16 and therefore on the completeness of the pressing. The holding element 16 is preferably made up at least in part from a hard material which is not greatly deformable by pressing forces such as polybutylene terephthalate (PBT), polyoxymethylene (POM], polyamide (PA), polyethylene terephthalate (PET) or polysulfone.
Recesses 22 are provided for the cutting elements not shown in Fig. 2, which in particular enable a form fit with the cutting elements. Corresponding embodiments of cutting elements are shown in Figs. 3a, b, c Figs. 3a, b show cutting elements 12 which are designed in a clamp shape and for example can be manufactured in a simple manner from a sheet of metal. In addition to a clamp-shaped base body 24 which can be combined with a holding element, cutting edges 26 are also provided. The cutting edges 26 can be arranged on one side or both sides of the base body 24. If the cutting edges 26 are provided on both sides, the cutting element 14 can cut into the material of the fitting in addition to the material of the workpiece. Fig. 3c shows a further embodiment of a cutting element 14 which has cutting edges 26 on both sides.
Figs. 4a, b are perspective views of embodiments of fixing elements 12 with combinations of the holding element 16 from Fig. 2 and the cutting elements from

Figs. 3b, c. Cutting elements 14 are set in the recesses 22 [see Fig. 2) of the holding element 16, which cutting elements 14 are distributed along the circumference of the holding element 16,
Fig. 4a shows a fixing element 12 with cutting elements 14 according to the embodiment from Fig. 3b. The cutting elements 14 can be clamped on the holding element 16 and therefore achieve a friction fit and/or a form fit with the holding element 16. A material fit connection can also be provided, for example an adhesive connection.
Fig. 4b further shows a fixing element 12 with cutting elements 14 according to the embodiment from Fig. 3c. The holding element 16 is only partially shown in Fig. 4b in order to make the arrangement of the cutting elements 14 clearer. The cutting elements 14 are connected to the holding element 16 in a material fit, for example by means of an adhesive connection or by means of insert moulding or extrusion-of the plastics material of the holding element 16 on the cutting elements 14.
The cutting elements 14 can in particular be arranged distributed along the circumference of the holding element 16 at equal distances and in a mirror-symmetrical pattern.
The use of individual, smaller cutting elements 14 made of metal in combination with a holding element 16 made of plastics material results in the material costs for the production of the fitting being reduced. At the same time the pressing outcome can be improved by the design of the fixing element 12.
Figs. 5a, b are perspective views of further, alternative embodiments of cutting elements 14. A ring-shaped element 28 is provided which is made of metal. The cutting element 14 has also cutting sections 30 being joined to the ring-shaped element 28 and have cutting edges 26. The ring-shaped element 28 and cutting sections 30 are preferably designed as one piece.

The cutting edges 26 are arranged on both sides in Fig. 5a, meaning the cutting element 14 can be used for pressing both into the materia) of a workpieceand into the material of the fitting. Fig. 5b shows a cutting element 14 with cutting edges 26 arranged on one side which can be pressed into the workpiece.
Fig. 6a is a perspective view of an embodiment of a fixing element with the embodiment of a cutting element 14 from [;ig. 5b. The cutting element 14 can be connected to the holding element 16 and therefore be held. The holding element 16 has recesses 22 to receive the cutting sections 30 of the cutting element 14.
Fig. 6b shows a second embodiment of a fitting 2 with the fixing element 12 from Fig. 6a and a pipe 6 which can be connected to the fitting 2. The fitting 2 further has a sealing clement 10 which can be arranged in the pressing section 6 of the fitting 2 together with the fixing element 12. The sealing element 10 is brought into direct contact with the fixing element 12, in particular with the ring-shaped element 28 of the cutting element 14. This means a separation ring between the sealing element 10 and the cutting element 14 can be avoided.
Fig. 7a is a lateral view of a third embodiment of a fitting 2 having a pipe 4. The cutting elements 14 are configured as clamps made from a sharp-edged sheet of metal clamped onto a ring-shaped holding element 16. As a result of their manufacture, the cutting elements 14 have a ridge which serves as a cutting edge 26 and in particular as shown in Fig. 7a can be bent outwards in a radial direction. The cutting elements' 14 preferred direction is in the axial direction of the holding element 16.
The holding element 16 is also designed as a stop and encircles the pressing area 6 on the end which faces away from the contact area 8. The holding element 16 therefore holds both the cutting element 14 and the sealing element 10 in their positions in the fitting 2, A separation ring 32 is optionally provided between the fixing element 12

and the sealing element 10, which separation ring 32 can protect the sealing element 10 from mechanical damage during pressing.
Fig. 7b is a perspective view of the fixing element 12 from Fig. 7a. The clamp-shaped cutting elements 14 comprise a sharp-edged sheet of metal which is clamped in an axial direction around a ring-shaped holding element 16. The cutting elements 14 can be arranged distributed along the circumference of the holding element 16 at equal distances. Figs. 7a, b show an embodiment of the fitting 2 which is particularly cost-effective to manufacture.
Fig. 8a is a lateral view of a fourth embodiment of a fitting 2 having a pipe 6. The cutting elements 14 are arranged in a radial direction of the holding element 12. If the fitting is pressed inwards in a radial direction in the pressing section 6, the cutting elements 14, held by the holding ring 16, will be pressed into the material of the pipe 4.
Fig. 8b is a perspective view of the corresponding fixing element 12 from Fig. 8a. The cutting elements 14 can be arranged distributed along at the circumference of the holding element 16 at equal distances. In order to produce the fixing element 12, the cutting elements 14 can be pressed in a radial direction into the material of the holding element 16 or introduced by means of insert moulding or extrusion. The fact that the cutting elements 14 have a greater radial extension than the radial wall thickness of the holding element 16 means that the fixing element 12 can be used for pressing within a fitting 2.
Figs. 9a, b show perspective views of embodiments of cutting elements 14 which can be used in the embodiment of fitting 2 or a fixing element 12, for example from Figs. 8a, b. These cutting elements 14 can be arranged in a radial or an axial direction on a ring-shaped holding element 16.

Fig. 9a shows a clamp-shaped cutting element 14 in a U-shape. This U-shape can be pressed into the material of the pipe 4. A cutting element 14 of this type can for example be manufactured in a simple manner by stamping from a sheet of metal and subsequent bending,
Fig. 9b also shows a ciamp-shaped cutting element 14 in a U-shape. In addition, a profiling 34 is arranged on the cutting element 14 which enables an improved connection to a holding element 16. In addition, the profiling 34 can also be configured such that it is pressed into the material of the pressing section 6 during
pressing in a fitting 2. A corresponding cutting clement 14 of this type can also be manufactured by stamping from a sheet of metal and subsequent bending,
Fig. 10 is a further perspective view of an embodiment of a fixing element 12. U-shaped cutting elements 14 are distributed according to the embodiment from Fig. 9a along the circumference of a holding element 16. The cutting elements 14 are arranged in their preferred direction in the axial direction of the fixing element, This means that a particularly cost-effective fixing clement 12 can be provided.
Fig. 11 is a further perspective view of an embodiment of a fixing element 12, which also has U-shaped cutting elements 14. The cutting elements 14 are designed in a similar manner to the embodiment from Fig. 9b and also have a profiling 34 which can be pressed into the material of a workpiece and optionally into the material of the fitting.
Fig. 12 is a further perspective view of an embodiment of a fixing element 12. The cutting elements 14 can alternatively be designed as a hat profile. In particular, the contact area between the cutting elements 14 and the holding element 16 can thereby be increased, resulting in a better hold on the cutting elements 14. The material of the holding element 16 can in particular penetrate the cutting elements 14. For example, the cutting element 14 has openings, wherein the material of the holding element 16 grips through the openings.

Fig. 13a is a lateral view of a system having an embodiment of a fitting 2 and a pressing tool 36. The pressing tool 36 is suitable for deforming the pressing area 6 of the fitting 2 and to create a leak-tight connection between the fitting 2 and a workpiece.
The pressing tool 36 is formed as a pressing ring. The pressing tool 36 has two pressing tool halves 38a, 38b which are pivotably mounted relative to one another by means of a connecting element, for example a hinge or a joint. The pressing tool halves 38a, 38b have base sections 42a, 42b for a pressing machine (not shown). An exertion of force on the base sections 42a, 42b can result in a receiving area 42 formed between the pressing tool halves 38a, 38b being narrowed.
A fitting 2 arranged in the receiving area 42 as shown in Fig. 13a can therefore be pressed in an inwards radial direction by means of 10 the exertion of force on the base sections 42a, 42b.
Fig. 13b shows, for clarification, a perspective view of the system from Fig. 13a with an embodiment of a fitting 2 and a pressing tool 36.
The fitting 2 is shown in Figs. 13a, b without the fixing element 12 for clarity. However, any embodiments of the above mentioned fixing element 12 can be used with the system made up of fitting 2 and pressing tool 36.

We Claim:
1. Fitting to create a leak-tight connection with a workpiece, in particular with a
pipe (4),
having at least one pressing area (6),
wherein at least one sealing element (10) and at least one fixing element (12) is
arranged in the pressing area (6),
wherein the fixing element (12) has at least one cutting element (14) made of a
hard material, in particular metal,
characterised in
that the fixing element (12) has at least one holding element (16) which is made
at least in part of a plastics material, and
that the holding element (16) holds the at least one cutting element (14).
2. Fitting according to claim 1, characterised in that the holding element (16) and the at least one cutting element (14) are connected to one another.
3. Fitting according to claim 1 or 2, characterised in that the fixing element (12) is in direct contact with the sealing element (10).
4. Fitting according to claim 3, characterised in that the at least one cutting element (14) has a ring-shaped element (28) which is in direct contact with the sealing element (10).
5. Fitting according to claim 1 or 2, characterised in that at least one additional separation element (32) is provided which is arranged between the sealing element (10) and the fixing element (12).

6. Fitting according to any one of claims 1 to 5, characterised in that the fixing element (12) is configured in a ring shape and has a plurality of cutting elements (14) which are arranged distributed along the circumference of the fixing element (12).
7. Fitting according to any one of claims 1 to 6, characterised in that the holding element (16) is made at least in part of polybutylene terephthalate (PBT), polyoxymethylene (POM), polyamide (PA), polyethylene terephthalate (PET) or polysulfone.
8. Fitting according to any one of claims 1 to 7, characterised in that the holding element (16) is designed to transfer a pressing force acting on the pressing section (6) to the at least one cutting element (14) when the fitting is being pressed.
9. Fitting according to any one of claims 1 to 8, characterised in
that a contact area (8) is provided for contact with a workpiece, and
that the pressing area (6) has at least one stop on the side facing away from the
contact area (8), which in particular is formed by the holding element (16).
10. Method for creating a leak-tight connection between a fitting and a workpiece, in
particular a pipe,
wherein at least one sealing element and at least one fixing element are arranged
in a pressing area of a fitting,
wherein the fixing element has at least one cutting element made of a hard
material, in particular metal, and at least one holding element made at least in
part from a plastics material and
wherein the at least one cutting element is held by the holding element,
wherein a workpiece is brought into abutment to the fitting,
wherein the fitting is pressed at least in the pressing area,

wherein the sealing element is pressed between the fitting and the workpiece
and
wherein the at least one cutting element is pressed into the material of the
workpiece.
11. Method according to claim 10, characterised in that the at least one cutting element is in addition also pressed into the material of the fitting.
12. Method according to claim 10 or 11, characterised in that during pressing, a pressing force exerted on the fitting is transferred to the at least one cutting element by means of the holding element.
13. Method according to any one of claims 10 to 12, characterised in that a friction fit and/or a form fit is achieved between the holding element and the workpiece.
14. Leak-tight connection between a fitting and a workpiece, in particular a pipe, wherein the leak-tight connection is created in particular using a method according to any one of claims 10 to 13,
having a fitting (2) according to any one of claims 1 to 9,
wherein the sealing element (10) is attached in a leak-tight manner between the
fitting (2) and the workpiece (4) and
wherein the at least one cutting element (14) is pressed into the material of the
workpiece (4).
15. Leak-tight connection according to claim 14, characterised in that the at least one
cutting element (14) is also pressed into the material of the fitting (2).