DE102012111803A1 - Method for preparing pressure capsule component, involves making welded connection between mating end and connection opening by resistance welding - Google Patents

Abstract

The method involves deploying the pressure can main portion (2). The straight connecting tube (3) is supplied with a plastically deformed mating end (4). The joining end is positioned at a connection opening (5) of the pressurized can main portion. The welded connection is made between the mating end and the connection opening by resistance welding. An independent claim is included for pressure cells component.

Description

FIELD OF THE INVENTION

The present invention relates generally, and more particularly, to a pressurized can component and a method of making the same.

BACKGROUND OF THE INVENTION

Pressure cans are pneumatic actuators, e.g. be used for bypass control of turbochargers. In this case, a negative or positive pressure is transmitted via a membrane to an actuating element, which then adjusts the amount of bypass gas to a turbocharger. The positive or negative pressure acts in a cup-like component, which receives a membrane at the open end. The closed interior of the pot is provided with a connection pipe. The underpressure or overpressure is built up within the pressure-box component via the connecting pipe, which then acts there accordingly on the membrane or the adjusting element.

The pressure can component typically forms a substantially cylindrical, pot-type, metallic deep-drawing component. In the wall or in the bottom of a connection opening is provided at a suitable location, which is provided with a connection pipe.

In known pressure-box components, this connecting pipe is inserted into the connection opening with a machined joining end, the edge of the joining end is caulked (crimped) with the pressure-side opening and then the existing joint between the connecting pipe end and connection opening of the pressure-box component is additionally gas-tight with a suitable brazing material. In a subsequent pressure test, the tightness of this connection can be checked.

However, this proven method has disadvantages. On the one hand, the loads occurring in a motor (vibrations, temperature, mechanical loads on the connection pipe) can lead to insufficiently fixed or incompletely soldered connection points between the pressure-cell component and the connection pipe becoming leaky. Such defective solder joints are not recognized despite the pressure test immediately after production under certain circumstances, as in mechanically caulked connections, the tightness is given despite a faulty solder joint initially by the positive connection. Only in operation loosens this connection and the connection is leaking, and then requires an exchange of the pressure box. On the other hand, if bent connections are required, the connection tubes must be hot-formed prior to joining (flanging, soldering), since steels which are machinable usually have only limited cold-forming properties.

To improve the joining quality, there is also the approach to weld the connection pipes with the connection opening of the pressure cell element. For this purpose, the Fügeendende the connecting pipe is provided with a well-defined, suitable for resistance welding geometry. The joining end is attached to the connection opening of the pressure cell component and a welding current is conducted through both elements, which causes the joining end to fuse with the connection opening. For the connection pipes so-called free-cutting steels are used, which are particularly suitable for mechanical, in particular machining. With these materials, the joining end can be designed exactly for the required weld geometry. However, with this method, only straight connection pipes can be reliably welded to pressure can bodies, since the required current flow properties, the welding parameters and the automated supply and installation of already curved connection pipes are difficult. Subsequent bending of such connection pipes is possible only with additional heat treatments because of the limited cold workability of the materials that can be used.

In modern engine arrangements, the space is very cramped. The pressure-dose connections must be suitable for very tight space conditions. This often requires that the connections be made not only axially, outgoing from the center of the pressure box floor, but also that the pressure box connection must be accessible from the side. For such a lateral outlet, the connection pipes must then be introduced laterally into the cylindrical wall of the pressure can body or the bottom must be provided with specially shaped connection areas / sockets from which the straight pressure pipes emanate.

In order to simplify or standardize the pressure can geometry, it is desirable to use curved connection tubes. This could be realized with the same junction box geometries both axial outlets and lateral outlets / connections to the pressure box. However, angled connection pipes are to produce limited according to the known methods. Soldered connections can lead to leaks and the welding of already pre-bent tubes increases the production effort and is technologically difficult to control.

It is therefore the object of an improved method for producing a To provide pressure can component or an improved pressure can component, which at least partially eliminates the disadvantages mentioned above.

SUMMARY OF THE INVENTION

• – Bereitstellen eines Druckdosenkörpers,
• – Zuführen eines geraden Anschlussrohres mit einem plastisch verformten Fügeende,
• – Positionieren des Fügeendes an einer Anschlussöffnung des Druckdosenkörpers und
• – Herstellen einer Schweißverbindung zwischen Fügeende und Anschlussöffnung mittels Widerstandsschweißen

durchgeführt werden.According to a first aspect, the present invention provides a method wherein, in the following order, the essential steps of the method

• Providing a pressurized can body,
• Feeding a straight connecting pipe with a plastically deformed joining end,
• - Positioning of the joining end to a connection opening of the pressure can body and
• - Establishment of a welded joint between the joining end and connection opening by means of resistance welding

be performed.

For connecting pipes, which are provided with a plastically deformed, in particular cold-formed or compressed joining end, corresponding compressible or deformable, ie ductile materials can be used. Thus, the required geometry of the joining end can be made with sufficient accuracy by cold working. The previously required mechanical (machining) machining is eliminated.

In addition, a connecting pipe made of such a material can also be bent cold. The existing after welding weld between the joining end and the connection opening is (in contrast to a solder joint) even so strong that the connecting pipe can be bent directly on the pressure can component in the desired manner. The pressure box component then serves at the same time as a fixation or "clamping". This makes it possible, on the one hand, to perform the welding process with a straight connecting pipe, which increases the process reliability and limits the production costs for the resistance welding process itself (electrodes) by the simple design. The simplified handling but also allows a higher timing in such typically automated manufacturing processes (easy feeding and handling of straight pipe sections, lower travel paths of the clamping (electrodes).

Another aspect relates to a pressure can component with a pressure can body, which has a connection opening, and a connection pipe with two ends, one of which is formed as a cold-formed joining end, which is connected to the connection opening by means of a welded connection, wherein pressure can body, connection opening, joining end, welded connection and Connecting pipe are formed so that the connecting pipe is providable with a bend, preferably with such a bend whose radius corresponds to at least 0.5 to 0.75 times the pipe diameter and / or the bending angle is up to 120 °, and the welded joint serves as a clamping during the bending process, that is suitable for receiving the loads occurring during the bending process.

Such a pressure cell component offers several advantages. The technically superior welded joint can also be used in conjunction with (subsequently) bent components. At the same time identical pressure box components can be designed both with a straight connection and with laterally or differently angled outgoing connection tubes, so that different connection geometries have no effect on the shape of the actual pressure box body itself.

Further aspects and features of the present invention will become apparent from the dependent claims, the accompanying drawings and the following description of preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWING

Embodiments of the invention will now be described by way of example with reference to the figures. Showing:

1 a perspective view of a pressure can component according to the invention with a straight connection pipe;

2 a perspective view of the in 1 illustrated pressure can component with subsequently bent connecting pipe;

3 an enlarged side view of the in 1 and 2 shown connection pipe; and

4 a flow diagram of a method according to the invention for the production of a pressure box component.

DESCRIPTION OF EMBODIMENTS

• – Bereitstellen eines Druckdosenkörpers,
• – Zuführen eines geraden Anschlussrohres mit einem plastisch verformten, insbesondere gestauchten Fügeende,
• – Positionieren und des Fügeendes an einer Anschlussöffnung des Druckdosenkörpers und
• – dem Herstellen einer Schweißverbindung zwischen Fügeende und Anschlussöffnung mittels Widerstandsschweißen

gibt es weitere Ausführungen des erfindungsgemäßen Verfahrens, die einen oder mehrere der folgenden Schritte aufweisen:

• – Bereitstellen eines Rohrhalbzeuges aus einem kaltverformbaren Stahl. Damit wird sichergestellt, dass eine prozesssichere und exakte Verformung des Fügeendes des Halbzeugs (unbearbeitetes Rohr) und die Biegung des bereits angeschweißten Anschlussrohres durchführbar ist.
• – Ablängen eines Rohrhalbzeugs zu einem Anschlussrohr Mit diesem Verfahrensschritt kann das Anschlussrohr auf die gewünschte Länge konfektioniert werden, sodass es entweder als gerade abgehender, meist koaxial zur Dosenachse verlaufender Anschluss, ausgebildet ist oder es kann bei längeren Ausführungen die Länge des Anschlussrohres so gewählt werden, dass mit dem Biegen um einen bestimmten Winkel an einer bestimmten Stelle des Anschlussrohres das Anschlussende und damit der Anschluss des Anschlussrohres an der gewünschten Position in der gewünschten Richtung ausgebildet ist.
• – Ausbilden einer Zentrierfläche am Fügeende mittels Kaltverformen (Kaltstauchen). Bei diesem Verfahren entfällt die u.U. aufwändige mechanische Bearbeitung. Darüber hinaus ist das Kaltverformen (z.B. Stauchen) eines solchen Rohres zeit- und werkstoffsparend, da keine Abfälle auftreten. Die ausgebildete Zentrierfläche, die in einer Stirnkante endet, ist für den Schweißvorgang und das Abschmelzverhalten beim Anschweißen wichtig.

In 1 is an embodiment and in 4 a method example in accordance with the present invention is illustrated. Before a detailed description, general explanations of embodiments will follow. In addition to the process steps:

• Providing a pressurized can body,
• Feeding a straight connecting pipe with a plastically deformed, in particular compressed joining end,
• - Positioning and the joining end to a connection opening of the pressure can body and
• - Making a welded joint between the joining end and connection opening by means of resistance welding

There are further embodiments of the method according to the invention, which have one or more of the following steps:

• - Providing a semi-finished tube made of a cold-workable steel. This ensures that a process-reliable and exact deformation of the joining end of the semifinished product (unprocessed pipe) and the bending of the already welded connection pipe can be carried out.
• Cutting to length of a semi-finished pipe to a connection pipe With this method step, the connection pipe can be made to the desired length, so that it is either designed as straight outgoing, usually coaxial to the socket axis extending connection, or it can be chosen with longer versions, the length of the connecting pipe so that with the bending by a certain angle at a certain point of the connection pipe, the connection end and thus the connection of the connection pipe is formed at the desired position in the desired direction.
• - Forming a centering surface at the joining end by cold forming (cold heading). This process eliminates the sometimes expensive mechanical processing. In addition, the cold forming (eg upsetting) of such a tube saves time and material, since no waste occurs. The trained centering, which ends in a front edge, is important for the welding process and the melting behavior during welding.

This method is characterized overall by the fact that a connecting pipe with a compressed (cold-formed) end is welded into a pressurized can body (resistance welding) and optionally can then be bent.

The advantages over the conventional manufacturing process include u.a. in that straight, simple components can be supplied (bending only after welding), no machined components are required (upsetting instead of turning, material better plastically deformable), the connection quality is improved (no subsequent leaks, as in soldering) and the Stemming as preparation for soldering is eliminated.

Further optional method steps relate to the bending of the connection pipe after the production of the welded connection.

In this case, the pressure can body is first fixed (clamped), the connection end or adjacent to the terminal end pipe section of the connection pipe is fixed (also by clamping in a tool or a clamping device) and between the pressure can body and connecting pipe section causing a bending relative movement is executed (eg pivotal movement). In this way, it is possible to perform the bending radius on the connection pipe very close to the welded connection between the joining end and the connection opening of the pressure box component. That The bend can be very space-saving and / or attached to relatively short connection tubes.

Another optional method step relates to a feed movement, which is carried out during the production of the welded connection between the pressure can body and the connection pipe. This improves the weld quality. In conjunction with the suitable design of the joining end and the connection opening of the pressure can body, it is thus possible to carry out a pronounced (seam cross-section) and with regard to the subsequent bending process loadable weld.

Relevant factors in the design of the pressure can body and its connection opening and the connecting pipe relate to the location, the bending angle and the radius of the pipe bend. With suitable coordination of the essential characteristics, such as Wall thickness, diameter of the connection pipe and diameter of the connection opening and the weld joint (seam cross section), it is possible to arrange the bend (transition from the straight section to the radius) so close to the pressure can body, that the distance between the bend and pressure can body is smaller than the diameter of the connecting pipe. The bending radius is between 0.4 and 0.9 times, preferably between 0.5 and 0.75 times the pipe diameter and the bending angle is up to 120 °.

There are embodiments in which the joining end of the connecting pipe has a frusto-conical outer contour as a centering surface, which has an opening angle of 60 ° -80 °, preferably of 65 ° -75 °. Such an outer contour is for the intended resistance welding (eg a projection weld after ISO 4063-23 ) particularly suitable to form a desired seam geometry. If a bead is formed at the joining end of the connecting pipe, the outer diameter of which is 1 to 3 mm, preferably 1.5 to 2 mm larger than the outer diameter of the connecting pipe and thus larger than the diameter of the connection opening on the pressure can body, the required during welding Delivery movement to be performed self-centering.

If an end edge is provided at the narrow end of the frusto-conical outer contour whose diameter is smaller than the diameter of the connection opening of the pressure can body, this likewise improves the desired properties of the weld joint with regard to the shaping, the effective seam cross section and the process reliability and tightness.

Coming back to 1 FIG. 1 illustrates a first embodiment and shows a pressure cell component 1 with a pressurized can body 2 and a connection pipe 3 ,

The connection pipe 3 is with its joining end 4 in / at the connection opening 5 of the pressure can body 2 fixed (welded). The other end of the connection pipe 3 serves as a connection end 6 and has, for example, for connecting a hose a Anschlussolive 7 on.

The pressurized can body 2 is designed as a cup-like cup, which has a flange at the open edge 8th and its bottom 9 with three star-shaped beads 10 is provided in a central recess 11 open, in the central one connection opening 5 is arranged. Pressure can body 2 and connecting pipe 3 are coaxial with the axis 12 arranged.

2 shows a pressure box component 1 in which the connection pipe 3 right-angled bending angle (β = 90 °) to the axis 12 is angled. The connection end runs here 6 along the axis 12 ' , The joining end 4 is with the connection opening 5 welded.

3 shows the structure of the connection pipe 3 , The connection pipe 3 is cut to length from a pipe semi-finished product, which has the outer diameter D and a wall thickness s. The starting material forms a cold-formable material such as E235 + N DIN EN 10305-1 ,

At the joining end 4 is by cold deformation (compression machining) a frustoconical outer contour 14 formed, which forms a centering surface. The opening angle is α to the axis 12 about 36 °. The outer contour 14 ends towards the end of the connection 6 in a bead 15 whose diameter W is 1.5 to 2 mm larger than the pipe diameter D. At its narrow end (Fügeende 4 ) ends the frusto-conical outer contour 14 in an annular end edge 16 with the diameter E.

In this case, the diameter A of the connection opening 5 that are centrally located in the depression 11 of the soil 9 in the pressure can body 2 is arranged larger than diameter E of the end edge 16 and smaller than the diameter W of the bead 15 , The frustoconical outer contour 14 the bead 15 , the diameter E of the front edge 16 , the wall thickness s and the diameter D of the connection pipe are matched to one another. The pressurized can body 2 is also partly in the 3 shown.

For welding, the frustoconical outer contour 14 centered on the connection opening 5 put on and a welding current through the connecting pipe 3 and the pressurized can body 2 directed. The front edge merge 16 or the outer contour 14 and the edge of the connection opening 5 together. When welding is a feed movement along the axis 12 executed by an amount of about 0.5 mm, to an intimate welding of the joining end 4 with the connection opening 5 to reach. To increase the weld quality, the welding process optionally takes place under a protective gas bell. After welding is a tight and load-bearing weld between the pressure can body 2 and the connection pipe 3 educated.

For bending the connection pipe 3 from the in 1 position shown in the in 2 shown position is the pressurized can body 2 fixed in a suitable jig and the connection pipe 3 in one to the terminal end 6 adjacent clamping area 17 clamped in a holder of a bending device. About a relative movement (eg a pivoting movement) between the holder and the jig, in which the pressure can body 2 is fixed, is now the connection pipe 3 bent by the angle β in the desired position. Because of the pressure can body 2 as fixation of the connection pipe 3 when bending serves, the bending radius R can be formed very close to the pressure can body itself, so that a very space-saving pressure can component 1 can be produced.

Between the bending radius R, the diameter D of the connection pipe 3 and whose wall thickness s has the following relationship (R = 0.5 to 075 D; s> 0.75 mm). The minimum distance between the joining end 4 and the beginning of the bending radius R is in dependence on the outer diameter D of the connection pipe 3 0.75 to 1.2 times the fold.

There are also versions where multiple bending radii in different directions on the connecting pipe 3 are formed.

• – Bereitstellen eines Druckdosenkörpers 2,
• – Zuführen eines geraden Anschlussrohres 3 mit einem kaltverformten Fügeende 4 und einem Anschlussende 6,
• – Positionieren und Fixieren des Fügeendes 4 an einer Anschlussöffnung 5 des Druckdosenkörpers 2,.
• – Herstellen einer Schweißverbindung zwischen Fügeende 4 und Anschlussöffnung 5 mittels Widerstandsschweißen sowie
• – das abschließende (optionale) Biegen des Anschlussrohres 3.

4 shows the sequence of a manufacturing method of the pressure can component according to the invention. Optional process steps are framed in dashed or dot-dash lines. The basic procedure comprises the following steps:

• - Providing a pressure can body 2 .
• - Supply a straight connection pipe 3 with a cold-formed joining end 4 and a connection end 6 .
• - Positioning and fixing the joining end 4 at a connection opening 5 of the pressure can body 2 .
• - Establishment of a welded joint between the joining end 4 and connection opening 5 by resistance welding as well
• - the final (optional) bending of the connection pipe 3 ,

• – Bereitstellen eines Rohrhalbzeugs aus einem kaltverformbaren Stahl, insbesondere ein ... (Beispiele ergänzen),
• – Ablängen des Rohrhalbzeugs,
• – Ausbilden eines Fügeendes 4 mittels Kaltverformen (Stauchen, Rollen, etc.).
• – Ausbilden eines Anschlussendes 6 mit einer Anschlussolive 7 mittels Kaltverformen.

Optionally, between steps can provide a pressurized can body 2 and supplying a straight connection pipe 3 one or more of the following steps are performed:

• - Providing a semi-finished tube made of a cold-workable steel, in particular a ... (Examples supplement),
• - cutting to length of the pipe semi-finished product,
• - Forming a joining end 4 by cold forming (upsetting, rolling, etc.).
• - Forming a connection end 6 with a connecting olive 7 by cold forming.

• – Fixieren des Druckdosenkörpers 2 in einer geeigneten Spannvorrichtung,
• – Fixieren eines an das Anschlussende 6 angrenzenden Rohrabschnitt 17 des Anschlussrohres 3,
• – Ausführen einer Biegebewegung zwischen Druckdosenkörper 2 und Anschlussrohrabschnitt 17.

After making the weld between the joining end 4 and the connection opening 5 By means of resistance welding, the optional bending of the connection pipe takes place 3 , if necessary, including the following steps:

• - Fix the pressure can body 2 in a suitable tensioning device,
• - Fix one to the connection end 6 adjacent pipe section 17 of the connection pipe 3 .
• - Performing a bending movement between the pressure can body 2 and connecting pipe section 17 ,

Further embodiments and modifications of the method according to the invention and of the pressure-dose component according to the invention will be apparent to those skilled in the art within the scope of the claims.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited non-patent literature

• ISO 4063-23 [0028]
• DIN EN 10305-1 [0034]

Claims (11)

Method for producing a pressure-dose component ( 1 ) with a pressure can body ( 2 ) Connection pipe ( 3 ) comprising the steps of: - providing the pressurized can body ( 2 ); - feeding a straight connecting pipe ( 3 ) with a plastically deformed joining end ( 4 ); - Positioning of the joining end ( 4 ) at a connection opening ( 5 ) of the pressure can body ( 2 ); - producing a welded connection between joining end ( 4 ) and connection opening ( 5 ) by resistance welding. The method of claim 1, further comprising the steps of: providing a semi-finished tube of cold workable steel; - Cutting a semi-finished pipe to a connecting pipe ( 6 ); - forming a centering surface ( 14 ) at the joining end ( 4 ) by cold heading. Method according to Claim 1 or 2, in which, following the production of the welded connection, the bending of the connection tube ( 6 ) he follows. The method of claim 3, wherein the bending of the connection pipe comprises the steps of: - fixing the pressure can body ( 2 ); - fixing a connection end ( 6 ) of the connecting pipe ( 3 ) in a tensioning device; - Performing a bending movement between the pressure can body ( 2 ) and connection end ( 6 ) by means of the tensioning device. Method according to claim 1, 2, 3 or 4, wherein, during the production of the welded connection, one along an axis ( 12 ) running delivery movement is executed. Pressure cell component ( 1 ) with a pressure can body ( 2 ), which has a connection opening ( 5 ) having a diameter (A), a connecting pipe ( 3 ) with two ends ( 4 . 6 ), one of which is the end of 4 ) is formed with the connection opening ( 5 ) is connected by means of a welded connection, wherein pressurized can body ( 2 ), Connection opening ( 5 ), End of joining ( 4 ), Welded joint and connecting pipe ( 3 ) are formed so that the welded connection pipe ( 3 ) with a bend, in particular with one whose radius (R) corresponds to at least 0.5 to 0.75 times the pipe diameter (D) and whose bending angle (β) is up to 120 °, and the welded joint can be used as a clamping during the bending process. Pressure cell component ( 1 ) according to claim 6, in which the bend is at a distance from the joining end ( 4 ) of less than 0.75 to 1.2 times the connection pipe diameter (D) is attachable. Connecting pipe ( 3 ) for use in a pressure can component ( 1 ) according to claim 6 or 7, wherein the joining end ( 4 ) a frustoconical outer contour ( 14 ), wherein an opening angle (α) of 60 to 80 °, preferably from 65 to 75 ° is provided. Connecting pipe ( 3 ) according to claim 8, wherein the frustoconical outer contour ( 14 ) a bead ( 15 ), whose outer diameter (W) is 1.5 to 2 mm larger than the connecting pipe diameter (D). Connecting pipe ( 3 ) according to claim 8 or 9, wherein the frusto-conical outer contour ( 14 ) at its narrow end a front edge ( 16 ) whose diameter (E) is smaller than the diameter (A) of the connection opening ( 5 ). Pressure cell component ( 1 ) according to claim 6 or 7, which by using a connection pipe ( 3 ) according to claim 8, 9 or 10 is produced by the method according to one of claims 1 to 5.

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