Method for manufacturing an electrically insulated support element

Abstract

Method for producing an electrically insulated support element (1) with a metallic sheath (2), and an inner region (3) surrounded by the sheath with exactly one metallic support pin (12) which is insulated from the metallic sheath (2) by a mineral insulation (18), wherein the method is carried out with a jet cutter (4) and comprises at least the following steps: a) Positioning the electrically insulated support element (1) relative to the beam cutter (4) such that a cutting beam (5) is tangent to a surface (9) of the metallic sheath (2); b) Activating the beam cutter (4); and c) Relative feed (16) of the electrically insulated support element (1) and the beam cutter (4) to each other, such that the metallic sheath (2) is cut by the cutting beam (5) along an at least partially axial separation line (6).

Description

[0001] The invention relates to a method for producing an electrically insulated support element with a metallic shell and an inner region surrounded by the shell, comprising a metallic support pin insulated from the metallic shell by a mineral insulation. The method is carried out using a jet cutter. Furthermore, the invention relates to the use of such an electrically insulated support element for supporting an electrical heating element.

[0002] The electrically insulated support element is particularly suitable for supporting electrical heating elements in exhaust gas treatment systems. Exhaust gas treatment systems are regularly subject to extremely demanding conditions, namely temperatures of several hundred degrees Celsius, along with significant temperature fluctuations and vibrations. In addition, most components in exhaust gas treatment systems are metallic, requiring reliable electrical insulation of electrical heating elements from other components of the exhaust gas treatment system.

[0003] DE 10 2020 102 810 A1 discloses a method for processing a sheathed thermocouple cable with a beam cutter.

[0004] JP 2012-110112 A discloses a screen cutting method and a screen cutting apparatus.

[0005] A support pin and a catalyst are known from DE 10 2018 213 358 A1.

[0006] Based on this, the invention disclosed here is based on the object of providing a method for producing electrically insulated support elements which are particularly suitable for the applications described.

[0007] According to the invention, this object is achieved by a method according to the teaching of claim 1. Preferred and advantageous embodiments of the method according to the invention are specified in the dependent claims. The individual embodiments can be used individually or in conjunction with one another.

[0008] The invention relates to a method for producing an electrically insulated support element with a metallic shell and an inner region surrounded by the shell with exactly one metallic support pin which is insulated from the metallic shell by a mineral insulation, wherein the method is carried out with a jet cutter and comprises at least the following steps: a) positioning the electrically insulated support element relative to the beam cutter so that a cutting beam is tangent to a shell surface of the shell; b) activating the beam cutter; and c) Relative advance of the electrically insulated support element and the jet cutter to each other, so that the metallic shell is separated by the cutting jet along an at least partially axial separation line.

[0009] The starting point for the process proposed here is a raw material, particularly in the form of an extruded material, which can be cut to specified lengths to form the electrically insulated support pins. The term "cutting" here refers to the raw material being cut from the extruded material to the desired length. It is then necessary to expose the metallic support pin inside the electrically insulated support element at one end in order to connect the metallic support pin to other components, e.g., a radiator that is to be supported by the support element.

[0010] The electrically insulated support elements preferably have a total length of between 5 mm [millimeters] and 150 mm. The outer sheath preferably has a diameter (sheath outer diameter) of between 1 mm and 20 mm, preferably 1.5 mm to 10 mm. The inner support pin preferably has a support pin diameter of between 0.5 mm and 10 mm. The finished electrically insulated support element has two mutually electrically insulated connection areas, to which two different components can be connected that are to be mechanically firmly connected to one another, but at the same time are to be electrically insulated from one another. One connection area is arranged on the outside of the sheath. The other connection area is arranged on the support pin where the sheath was removed from the support pin using the described method.

[0011] The starting material for the production of the electrically insulated support elements is, as already mentioned above, available as extruded material. To produce an electrically insulated support element, a piece of extruded material is cut to the required length for the respective support element. The length depends, for example, on the desired distance between the support body and the heating element.

[0012] The metallic casing is designed in the style of a pipe. The metallic casing is made of stainless steel, for example.

[0013] The inner support pin is preferably made of the same material as the sheath. The support pin is arranged in the inner region surrounded by the metallic sheath. The support pin is insulated from the metallic sheath by a mineral insulating material arranged in the inner region. This material can be, for example, a ceramic material.

[0014] The starting material for the support pin can be produced, in particular, through a drawing process. This involves continuously reducing the diameter of the starting material. The shell, the inner region, and the inner support pin deform together, allowing support pins with very small diameters to be produced.

[0015] The wall thickness (sheath thickness) of the metallic sheath is preferably between 5% and 20% of the outer diameter. For an outer diameter of 5 mm, the wall thickness can therefore be between 0.5 mm and 1 mm. The metallic sheath accordingly has an inner diameter between 4 mm and 3 mm. In very special designs for very specific applications, the wall thickness can be up to 45% of the outer diameter.

[0016] The diameter of the support pin (support pin diameter) is between 5% and 89% of the outer shell diameter.

[0017] The described size and thickness ratios result in a very high stability of the electrically insulated support element

[0018] In particular, the sheath must be removed with minimal force, as the applied forces risk damaging or even destroying the inner metallic support pin and thus impairing the overall durability of the electrically insulated support element.

[0019] In process step a), the term “tangential contact” means that the cutting beam of the jet cutter runs like a tangent to the jacket surface. The cutting beam touches and cuts from the surface of the metallic jacket into the electrically insulated support element with a specific cutting depth. The cutting depth determines how far the beam penetrates from the surface of the metallic jacket into the electrically insulated support element. The cutting depth depends, for example, on the property (e.g. diameter) of the cutting beam, which can be adjusted as required. The cutting depth is preferably selected so that it corresponds to the thickness of the metallic jacket. This ensures that the metallic jacket is completely severed by the jet cutter and at the same time the interior area or the (inner) metallic support pin is not damaged by the jet cutter. When the jet cutter is activated in step b), the cutting jet is created and the cutting of the jacket begins.

[0020] Preferably, in method step c), the electrically insulated support element and / or the jet cutter are advanced relative to each other at least partially along an axis of the electrically insulated support element. This relative advance movement creates an at least partially axial severing line on the casing by the cutting jet. The severing line runs, for example, at least partially parallel to the direction of advance. It can be viewed as a line defined by the intersection points (contact points) between the cutting jet and the casing of the electrically insulated support element that occur during the advance movement.

[0021] The method is particularly preferred when the beam cutter is a laser cutter. Of course, other types of beam cutters are also applicable. Possible types of beam cutters that may be applicable for the described method include, for example, waterjet cutters or plasma cutters.

[0022] It has been found that a metallic sheath of an electrically insulated support element can also be easily separated using a laser cutter.

[0023] The method is further advantageous if the positioning in step a) is carried out in such a way that the cutting beam does not touch the inner area of ​​the electrically insulated support element.

[0024] As already explained above, the (inner) metallic support pin, which should not be damaged, is located in the inner region. Furthermore, the inner region can comprise, for example, electrically insulating materials (e.g., ceramic) that surround the (inner) metallic support pin, protect it, and insulate it from the jacket. Preferably, such electrically insulating materials are also not damaged by the cutting beam. Such electrically insulating materials are removed, if necessary, in a subsequent processing step.

[0025] The method is further advantageous if the cutting beam in step a) is positioned at a right angle to an axis of the electrically insulated support element.

[0026] The axis of the electrically insulated support element describes the orientation of the electrically insulated support element in the area where the described process takes place. This is the area in which the cutting beam of the jet cutter acts on the electrically insulated support element and, if applicable, also on the immediate surroundings of this area. By arranging the cutting beam and the axis of the electrically insulated support element at a right angle to each other, the length of the cutting line can be adjusted particularly precisely by axial displacement along the axis.

[0027] The method is further advantageous if the jet cutter is activated at one end of the electrically insulated support element or in front of one end of the electrically insulated support element and step c) is carried out in such a way that an at least partially axial dividing line of the metallic sheath is formed, extending from the end of the electrically insulated support element.

[0028] The beam cutter is activated in process step b), and the beam cutter is located at one end of the electrically insulated support element or in front of one end of the electrically insulated support element during activation, so that the electrically insulated support element is not yet processed by the cutting beam before the relative feed begins in process step c). Processing of the electrically insulated support element preferably begins only after the relative feed has been initiated.

[0029] The feed creates an at least partially axial separation line of the metallic sheath, which extends from the end of the electrically insulated support element at least partially along the axis of the electrically insulated support element, wherein the metallic sheath is separated by the cutting beam along this at least partially axial separation line.

[0030] The method is further advantageous if the at least partially axial dividing line extends from the end between 2 mm [millimeters] and 75 mm along an axis of the electrically insulated support element. Starting from the end of an electrically insulated support element along an axis of the electrically insulated support element, the length of the at least partial parting line is defined in the axial direction. The length of the at least partial axial parting line can also be longer than 75 mm or shorter than 2 mm. However, it has been found that an axial parting line between 75 mm and 2 mm achieves good accessibility of the inner metallic support pin for mounting an electric heater, while simultaneously generating relatively low waste of starting material.

[0031] Preferably, the axial separation line extends over a length corresponding to between 25 percent and 75 percent of the length of the electrically insulated support element (in each case starting from one end of the electrically insulated support element).

[0032] The method is further advantageous if the feed in step c) takes place along an axis of the electrically insulated support element.

[0033] If the feed in method step c) is carried out along an axis of the electrically insulated support element, the direction of movement of the feed preferably runs parallel to the axis of the electrically insulated support element.

[0034] It is also possible for the feed to occur at an angle to the axis of the electrically insulated support element, in which case a lateral displacement of the beam cutter relative to the electrically insulated support element occurs simultaneously with the axial feed. In particular with a laser beam cutter, a lateral distance is of secondary importance for the function of the beam cutter, so that a lateral displacement is not to be considered critical. This is because the effect of the beam cutter is only very slightly dependent on the distance between the tool and the workpiece, because the properties of a laser beam are not significantly changed by a change in the distance. This can be different, for example, if a different type of beam cutter is used, e.g. a waterjet cutter.

[0035] In further embodiments, the jet cutter is fixedly positioned relative to the electrically insulated support element. A relative advance in step c) is achieved by rotating the jet cutter at the fixed position, and the cutting jet thereby separates the metallic casing along the separation line. The method is further advantageous if, during the advance, the electrically insulated support element rotates around an axis, and the at least partially axial separation line extends in a spiral manner around the casing surface.

[0036] By adjusting the feed rate along the axis of the electrically insulated support element and the rotation speed, the angle of the spiral path relative to a circumferential direction of the electrically insulated support element can be determined. The spiral shape of the separation line preferably creates a similarly spiral-shaped section of the metallic sheath, which can be unwound from the interior of the electrically insulated support element to remove this spiral-shaped, severed section of the metallic sheath.

[0037] The method is particularly advantageous if the (spiral-shaped) at least partially axial dividing line has a gradient of less than 70°. The gradient of the spiral-shaped, at least partially axial dividing line can influence the degree of spiral shape of the spiral-shaped, severed shell section.

[0038] In preferred embodiments, the gradient is less than 40° (angular degrees) and particularly preferably even less than 15° or even less than 10°.

[0039] Preferably, the pitch is selected such that the spirally severed sheath section (locally) (in the axial direction of the electrically insulated support element) has a maximum width of half the length of the region in which the metallic sheath is severed from the electrically insulated support element. The severed sheath section preferably encircles the circumference of the electrically insulated support element at least twice, particularly preferably at least three times, and most particularly preferably even at least five times. As a result, the severed sheath section can be removed more easily (i.e., with reduced force). This reduces the risk of damage to the (inner) metallic support element when removing the severed sheath section.

[0040] The method is further advantageous if the following step is carried out after or before step c): d) Rotating the electrically insulated support element around its axis, creating a circumferential dividing line of the sheath and thus a separated sheath section.

[0041] During step d), in particular, no further feed along the axis of the electrically insulated support element occurs. A circumferential dividing line is created between the severed shell section and the remaining shell, which extends only in the circumferential direction of the electrically insulated support element.

[0042] The order of process steps c) and d) can be determined depending on the additional requirements. If process step c) is performed first, the axial parting line in step c) is normally created from the end of the electrically insulated support element toward the electrically insulated support element. If process step d) is performed first and then process step c), the axial parting line is normally created from the electrically insulated support element toward the end of the electrically insulated support element.

[0043] After reaching the desired length of the axial parting line (desired machining length) of the electrically insulated support element, the axial feed is stopped. The electrically insulated support element is then rotated about its axis, for example, about its central axis, so that the described circumferential parting line of the casing is created by the tangency of the cutting beam with the casing. The term "circumferential" means that after one rotation of the electrically insulated support element, the first intersection point on this circumferential parting line coincides with the cutting beam and a final intersection point on the circumferential parting line coincides with the cutting beam. The circumferential parting line thus forms the shape of a closed circle. The method is further advantageous if the following step is carried out after step d): e) Removing the severed sheath section and exposing the (inner) metallic support pin in the interior area.

[0044] Removing the severed sheath section preferably comprises bending the severed sheath section upwards from the inner region or unwinding the severed sheath section from the inner region. Particularly if a spiral axial separation line and a spirally severed sheath section were created by rotation of the electrically insulated support element during axial advance, the severed sheath section can be unwound from the inner region of the electrically insulated support element in a spiral manner.

[0045] When exposing the (inner) metallic support pin in the interior, material surrounding the support pin is preferably also removed. As already explained above, this can be, for example, an insulating material made of ceramic, particularly a mineral insulation. The material in the interior is preferably porous and can be easily removed. If necessary, the material is tapped out of the interior and / or removed by vibrations and movements resulting from the removal of the severed casing section.

[0046] In preferred embodiments, the mineral insulation is porous in the interior. In this case, it is particularly preferred if the mineral insulation is removed with minimal dust generation, particularly preferably in one piece.

[0047] In particular, if the mineral insulation is not or only partially porous and there may also be adhesion of the mineral insulation to the metallic sheath, to the (inner) metallic support pin, etc., it is advantageous if no or only a small force (small moments) is exerted on the inner metallic support pin during removal.

[0048] In a further embodiment, at least two axial separation lines are created or the metallic shell is separated along at least two axial separation lines.

[0049] To create at least two axial separation lines, multiple jet cutters with cutting jets can be used, which may act in parallel (simultaneously) on the electrically insulated support element. It is also possible for the at least two axial separation lines to be created sequentially, with particular preference given to multiple feed movements during which the at least one jet cutter creates the separation lines or the casing is separated along the respective separation lines.

[0050] Particularly preferably, the metallic shell is divided by the at least two axial dividing lines in such a way that several separated shell sections are created, each of which preferably has the same size or, in particular, the same extent in the circumferential direction. Particularly preferably, two dividing lines and two separated shell sections are created. In further embodiments, three or more dividing lines and separated shell sections can also be created. The creation of several separated shell sections simplifies the removal of the separated shell sections. If necessary, bending the separated shell section can also be omitted when removing the separated shell sections.

[0051] Also to be described here is an electrically insulated support element which is manufactured according to the described method.

[0052] The electrically insulated support element has two connecting areas electrically separated from each other by the mineral insulation. One connecting area is located on the (inner) metallic support pin, and another connecting area is located on the metallic casing. These connecting areas can each be attached to a carrier body or to a heating element to create an electrically insulated connection between the heating element and the carrier body. The connection of the connecting areas can be achieved, for example, by soldering or welding.

[0053] Therefore, the use of an electrically insulated support element for supporting an electric heating element on a metallic support body is particularly preferred, wherein the metallic casing or the metallic support pin is connected either to the electric heating element or to the metallic support body, so that the mineral insulation electrically insulates the electric heating element from the metallic support body. The connection to the electric heating element and / or to the metallic support body is preferably realized at the connection areas with soldered and / or welded joints.

[0054] The invention is explained in more detail below with reference to the figures. It should be noted that the figures show preferred embodiments to which the invention is not limited. They show: Fig. 1: an electrically insulated support element during the described process with axial separation line, Fig. 2: an electrically insulated support element with a spiral dividing line, Fig. 3: the use of an electrically insulated support element to support a heating element, Fig. 4: a flow chart of the described procedure, Fig. 5: another electrically insulated support element with a spiral dividing line, Fig. 6: a cross-section through an electrically insulated support element, Fig. 7: another electrically insulated support element, and Fig. 8: yet another electrically insulated support element.

[0055] Fig. 1 shows a cylindrical, electrically insulated support element 1, which comprises an inner metallic support pin 12 embedded in the interior region 3 of the electrically insulated support element 1 and a metallic casing 2. A beam cutter 4, which is capable of processing the electrically insulated support element 1, is arranged at a distance from the electrically insulated support element 1. The beam cutter 4 can be, for example, a laser cutter. The electrically insulated support element 1 and the beam cutter 4 are positioned such that, after activation of the beam cutter 4, the cutting beam 5 is perpendicular to the axis 7 of the cylindrical, electrically insulated support element 1 and touches and cuts the metallic casing 2 of the electrically insulated support element 1 as a tangent.The axis 7 here represents the central axis of the electrically insulated support element 1, along which the electrically insulated support element 1 is aligned in the area that is machined with the jet cutter 4 or the cutting jet 5. The cutting jet 5 is preferably aligned and adjusted such that the metallic casing 2 of the electrically insulated support element 1 is severed, but the inner region 3 or the (inner) metallic support pin 12 is not affected. In the inner region 3 there is preferably a mineral insulation 18 in which the (inner) metallic support pin 12 is embedded. By appropriately positioning the jet cutter 4 or the cutting jet 5 relative to the electrically insulated support element 1, a cutting depth 22 of the cutting jet 5 into the electrically insulated support element 1 is adjusted.

[0056] After activating the beam cutter 4, the processing of the electrically insulated support element 1 begins. In the variant according to Fig. 1 from one end 8 of the electrically insulated support element 1.

[0057] According to process step c), an axial separation line 6 of the metallic shell 2 is created, extending from the end 8 along the axis 7. The axial separation line 6 is generated by the relative advance 16 of the electrically insulated support element 1 and the beam cutter 4.

[0058] The relative feed 16 is achieved, for example, by advancing the beam cutter 4 along axis 7 while the electrically insulated support element 1 remains stationary; and / or conversely, by advancing the beam cutter 4 while the electrically insulated support element 1 is advanced along axis 7. In another possible embodiment, the electrically insulated support element 1 and the beam cutter 4 are advanced simultaneously relative to one another along axis 7. It is only important that a relative feed 16 is performed between the electrically insulated support element 1 and the beam cutter 4 along axis 7.

[0059] Subsequently (after process step c) or at the conclusion of process step c)), the advance of the jet cutter 4 is stopped. This occurs after the axial separating line 6 has reached a desired length 30 due to the advance. Preferably, in process step d), the electrically insulated support element 1 is then rotated about the axis 7. The jet cutter 4 continues to operate with the cutting jet 5, so that a separating line 10 of the metallic casing 2 is created, extending along a circumferential direction 24 of the electrically insulated support element 1.

[0060] Preferably, the electrically insulated support element 1 and the jet cutter 4 are positioned during process steps c) and d) such that the inner region 3 of the electrically insulated support element 1 is not affected or impaired by the cutting jet 5.

[0061] In combination with the axial parting line 6 and the circumferential parting line 10, a severed sheath section 11 is created. According to method step e), the severed sheath section 11 is removed from the electrically insulated support element 1. In doing so, the severed sheath section 11 is preferably bent open or peeled off. The (inner) metallic support pin 12 is embedded in the inner region 3 of the electrically insulated support element and is preferably surrounded by a mineral insulation 18, which consists, for example, of ceramic. After removal of the sheath section, the (inner) metallic support pin 12 can be exposed in the inner region 3 by removing the mineral insulation 18.

[0062] Fig. 2 shows a further embodiment of the electrically insulated support element 1, which is processed using the described method. Fig. 1 and Fig. 2 agree in many respects. Here, we would like to focus on the differences between Fig. 2 opposite the Fig. 1. Otherwise, the explanations for the Fig. 1. In comparison to the electrically insulated support element 1 in Fig. 1, in method step c), the electrically insulated support element 1 is rotated about its axis 7 during the relative advance 16 along the axis 7 of the electrically insulated support element 1, so that the axial parting line 6 created by the jet cutter runs around the lateral surface 9 in the manner of a cylindrical spiral. The course of this spiral parting line 6 comprises an axial component that is aligned parallel to the axis 7 of the electrically insulated support element 1 and results from the advance 16 along the axis 7. The course of this spiral parting line 6 further comprises a rotational component from the rotation 17 of the electrically insulated support element 1 about its axis 7. Thus, the spiral parting line is also partially axial.An angle 23 of the parting line 6 to a circumferential direction 24 of the electrically insulated support element 1 can be determined by the ratio of the feed speed in the direction of the axis 7 and the rotation speed about the axis 7. The feed 16 of the beam cutter 4 is stopped when the parting line 6 has reached a desired length in the axial direction (along the axis 7). The electrically insulated support element 1 continues to rotate about its axis 7 while the feed 16 is stopped, so that a circumferential parting line 10 is created on the metallic jacket 2. In combination with the spiral parting line 6 and the circumferential parting line 10, a severed jacket section 11 is created, which also has a spiral shape. Due to the spiral parting line 6, the shape of the jacket section 11 differs in . Fig. 2 from the shape of the shell section 11 in Fig. 1. The spiral-shaped separating line 6 makes it possible in a particularly advantageous manner (in particular particularly easily and quickly) to separate the sheath 2 from the electrically insulated support element 1. If necessary, the separated sheath section 11 can be more easily unwound from the inner region 3 of the electrically insulated support element 1.

[0063] Fig. 3 shows, by way of example, an electrical heating element 14 supported on a support body 13 by means of the described electrically insulated support elements 1. Both the electrical heating element 14 and the support body 13 can be metallic honeycomb bodies that are electrically insulated from one another by means of the mineral insulation 18 of the electrically insulated support elements 1. Preferably, each electrically insulated support element 1 has two connecting regions 33, which can each be connected to different, electrically insulated components using soldered connections and / or welded connections—in the present case, to the heating element 14 and to the support body 13. One connecting region 33 is located on the inner metallic support pin 12. The components are connected to the connecting regions 33, for example, by soldering and / or welding. Another connecting region 33 is located on the metallic casing 2.The electrical heating element 14 has electrical contacts 15 with which the electrical heating element 14 can be supplied with an electrical heating current.

[0064] Fig. Figure 4 shows a flowchart of the described process. It shows process steps a), b), c), d), and e), which are performed sequentially.

[0065] Fig. 5: shows a further electrically insulated support element 1 with a spiral axial separation line 6. Also with regard to this embodiment, reference is made to the explanations of the Fig. 1 and Fig. 2. The spiral, at least partially axial, parting line 6 here has a very slight pitch 29. This pitch 29 can be understood as the angle between the circumferential direction 24 and the spiral, at least partially axial, parting line 6. In this embodiment, the at least partially axial parting line 6 circles the electrically insulated support element 1 several times in the circumferential direction 24. This results in a spiral, severed casing section 11 if the described method is carried out accordingly. This spiral, severed casing section 11 can, for example, be unwound in the unwinding direction 25, starting from the starting point 21 to the end point 20, with particularly little force being applied. It can be seen that the spiral, severed casing section 11 circles the circumference of the electrically insulated support element 1 several times.In particular, the necessary force is lower due to the spiral shape of the severed sheath section 11 than if the severed sheath section 11 were not spiral-shaped. This allows for greater certainty that the (inner) metallic support pin 12 will remain intact when the severed sheath section 11 is detached.

[0066] Fig. Figure 6 shows a cross section through an electrically insulated support element 1 which is machined using the described method. Fig. The geometric properties of an electrically insulated support element 1 in cross-section shown in Figure 6 are transferable to all other embodiments of electrically insulated support elements 1 shown here and accordingly also apply to these embodiments. The metallic shell 2 and the (inner) metallic support pin 12 can be seen. Fig. 6 also shows the dimensions of the electrically insulated support element 1. These dimensions can be applied to all embodiments. The support element 1 has a total length 34, and the sheath 2 has been removed over a length 30 using the described method, resulting in a remaining sheath length 35. The sheath 2 has an outer sheath diameter 27 and a sheath thickness 37, resulting in an inner sheath diameter 26. The (inner) metallic support pin 12 has a pin diameter 36. The mineral insulation 18 is arranged between the (inner) metallic support pin 12 and the metallic sheath 2, ensuring an insulating distance 38 between the sheath 2 and the (inner) metallic support pin 12.

[0067] Fig. Figure 7 shows yet another electrically insulated support element 1 in a three-dimensional view, showing conditions that arise when the severed sheath sections 11 are detached. It can be seen that the severed sheath sections 11 are separated from the metallic sheath 2 along two axial separation lines 6 and along the circumferential separation line 10, so that the inner region 3 with the mineral insulation 18 and the (inner) metallic support pin 12 with a length of 30 mm is exposed.

[0068] The parting line positions 28 of the two axial parting lines 6 can be seen. For better illustration, the two axial parting lines 6 are each shown here on the lower severed casing section 11. If the two severed casing sections 11 are mentally placed back on the support element 1, the positions of the axial parting lines 6 can be seen. The separation of the severed casing sections 11 preferably takes place in the direction of the separating movement 31 shown here. Particularly preferably, forces on the (inner) metallic support pin 12 are controlled in order to avoid damage to the (inner) metallic support pin 12. In this case, first bending moments 32, which act perpendicular to the parting lines 6, and second bending moments 19, which act parallel to the parting lines 6, can be differentiated from one another and each applied in a targeted manner.

[0069] Fig. Figure 8 shows a further electrically insulated support element 1, wherein reference is also made to the explanation of the preceding figures with regard to the reference numerals. Fig. 8 shows a type of machining of the electrically insulated support element 1, in which first the circumferential separating line 10 is created, wherein a rotation 17 of the electrically insulated support element 1 occurs while the cutting beam 5 of the jet cutter 4 acts on the electrically insulated support element 1. The circumferential separating line 10 is created such that the severed casing section 11 has the desired length 30. As soon as the circumferential separating line 10 has been completely created, the axial separating line 6 is subsequently created with the jet cutter 4 and the cutting beam 5, wherein the feed 16 is now produced in the opposite direction from the circumferential separating line 10 towards the end 8 of the electrically insulated support element 1. The order of process steps c) and d) is therefore reversed and process step d) is carried out first, followed by process step c). In the embodiment according to Fig. 8 also shows that two jet cutters 4 with cutting jets 5 act simultaneously on the electrically insulated support element 1 to create axial separation lines 6 or the corresponding separation. The two cutting jets can also be used in parallel to create the circumferential separation line 10, in which case only half a rotation 17 in the circumferential direction (by 180°) is required to achieve a completely circumferential separation. Fig. The principle shown in Figure 8 of working with two jet cutters 4 and the principle shown there of first creating the circumferential parting line 10 (step d)) and then the at least partially axial parting line (step c)) can be used independently of each other. List of reference symbols 1 support element 2 metallic sheath 3 Interior 4 jet cutters 5 Cutting beam 6 spiral / at least partially axial dividing line 7 Axis 8 End 9 Shell surface 10 circumferential dividing line 11 separated jacket section 12 metallic support pin 13 carrier bodies 14 electric heating element 15 electrical contact 16 Feed 17 rotation 18 mineral insulation 19 second bending moment 20 Endpoint 21 Starting point 22 cutting depth 23 angles 24 Circumferential direction 25 Unwinding direction 26 shell inner diameter 27 outer shell diameter 28 Divider position 29 gradient 30 length 31 Separation movement 32 first bending moment 33 Connection area 34 total length 35 remaining sheath length 36 pin diameter 37 jacket thickness 38 Insulation distance

Claims

[1] Method for producing an electrically insulated support element (1) with a metallic casing (2) and an inner region (3) surrounded by the casing with exactly one metallic support pin (12) which is insulated from the metallic casing (2) with a mineral insulation (18), wherein the method is carried out with a jet cutter (4) and comprises at least the following steps: a) positioning the electrically insulated support element (1) relative to the jet cutter (4) so ​​that a cutting jet (5) is tangent to a lateral surface (9) of the metallic jacket (2); b) activating the jet cutter (4); and c) relative advance (16) of the electrically insulated support element (1) and the jet cutter (4) to one another, so that the metallic casing (2) is separated by the cutting jet (5) along an at least partially axial separating line (6). [2] Method according to claim 1, wherein the beam cutter (4) is a laser cutter. [3] Method according to claim 1 or 2, wherein the positioning in step a) is carried out such that the cutting beam (5) does not touch the inner region (3) of the electrically insulated support element (1). [4] Method according to one of the preceding claims, wherein the cutting beam (5) in step a) is positioned at a right angle to an axis (7) of the electrically insulated support element (1). [5] Method according to one of the preceding claims, wherein the jet cutter (4) is activated at one end (8) of the electrically insulated support element (1) or in front of one end (8) of the electrically insulated support element (1) and step c) is carried out in such a way that an at least partially axial dividing line (6) of the metallic casing (2) is formed, extending from the end (8) of the electrically insulated support element (1). [6] Method according to claim 5, wherein the at least partially axial dividing line (6) extends from the end (8) with a length (30) between 2 mm [millimeters] and 75 mm along an axis (7) of the electrically insulated support element (1). [7] Method according to one of the preceding claims, wherein the feed (16) in step c) takes place along an axis (7) of the electrically insulated support element (1). [8] Method according to one of the preceding claims, wherein during the feed (16) a rotation (17) of the electrically insulated support element (1) takes place about an axis (7), and the at least partially axial separating line (6) runs in the manner of a spiral around the lateral surface (9). [9] Method according to one of the preceding claims, wherein the at least partially axial dividing line (6) has a gradient (29) of less than 70°. [10] Method according to one of the preceding claims, wherein the following step is carried out after or before step c): d) rotating the electrically insulated support element (1) about its axis (7), whereby a circumferential separating line (10) of the sheath and thus a separated sheath section (11) is formed. [11] Method according to claim 10, wherein after step d) the following step is carried out: e) Removing the separated jacket section (11) and exposing the metallic support pin (12) in the interior area (3). [12] Method according to one of the preceding claims, wherein at least two axial parting lines (6) are produced. [13] Electrically insulated support element (1) manufactured according to the method according to any one of the preceding claims. [14] Use of an electrically insulated support element (1) produced according to the method according to the preceding claims 1 to 12 for supporting an electrical heating element (14) on a metallic support body (13), wherein the metallic casing (2) or the metallic support pin (12) are each connected either to the electrical heating element (14) or to the metallic support body (13), so that the mineral insulation (18) electrically insulates the electrical heating element (14) from the metallic support body (13).

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