Fuel injection system, component, in particular pressure regulator or fuel distribution device, and connection for fuel injection systems for gaseous fuels, in particular hydrogen
Patent Information
- Application Number
- DE102023209784
- Authority / Receiving Office
- DE · DE
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-10-06
- Publication Date
- 2025-04-10
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
Prior ArtThe invention relates to a fuel injection system for gaseous fuels, in particular hydrogen. The invention relates in particular to the field of fuel injection systems for motor vehicles.DE 10 2006 040 236 A1 discloses a fuel plant for compressed gaseous fuel, in particular natural gas or hydrogen, for an internal combustion engine. The known fuel system has a common rail and a pump. Further provided are a tank for compressed gaseous fuel, in particular natural gas or hydrogen, and an upstream pressure regulator where the pressure is reduced from the tank pressure, which may range to near 5000 psi (34 MPa) or more, to a first reduced pressure of about 400 psi (2.8 MPa). Once the fuel exits the upstream pressure regulator, it moves to a downstream pressure regulator where the fuel is lowered to about 200 psi (1.4 MPa). The fuel then moves to a control regulator. An electronic control unit operates the control regulator such that the fuel is lowered at the second working pressure, in this case approximately 200 psi, to a variable control pressure arranged by the electronic control unit. The fuel supply via common rail nozzles can thereby be increased or decreased.The fuel system known from DE 10 2006 040 236 A1 has the disadvantage that high production costs are produced, so that operation with compressed hydrogen is possible. In particular, the material from which the individual components, in particular the pressure regulators, are produced must be selected such that all existing requirements can be fulfilled. The selection of material is based on the highest requirement, although these can be very different in individual sub-regions of the fuel system.At the same time, selected manufacturing methods for the components, such as casting or forging, and joining methods for joining individual components or individual components, such as brazing, welding or screwing, affect the selection of suitable materials. This limits the use of specific materials and the use of specific methods for producing the components and components.In fuel injection systems for gaseous fuels, special requirements are also placed. As a result, measures which are used in fuel systems for liquid fuels can be disadvantageous in applications for gaseous fuels. Further, hydrogen is more volatile than natural gas. In a fuel injection system for hydrogen, for example, a specification regarding the permissible amount of escaping hydrogen may have to be maintained. This then exists in particular with a view to preventing the ignition of escaping hydrogen.In a fuel injection system for hydrogen, the quantity and thus the pressure of the hydrogen in a connected rail can be regulated via a pressure regulator. For the connections between the tank and the rail, lines can be used which are fastened to screw-in connectors which are in turn screwed into housings. Such screw-in connectors can likewise be provided on the rail.A seal must be ensured between such components, in particular a housing and a screw-in connection piece. In principle, a seal can be realized by a bite edge on one of the components, which ensures a metallic seal of the interface. An O-ring can additionally be used as an additional safety device. In principle, a pure seal can also be realized via an O-ring or a flat seal in the thread base of the screw-in connection piece, in particular a double connection piece.However, special problems arise in the field of use of the fuel injection systems for hydrogen. With a bite edge seal or a seal by means of an O-ring or flat seal (flat sealing ring), it is only possible to seal. In practice, however, strong vibrations can arise during operation or on the vehicle, which can lead to loosening and possibly even to unscrewing of screw connections. Thus, leaks can occur at the fuel injection system, which lead to the escape of hydrogen.In practice, in the event of repair, screwing on and closing the connection between a pressure regulator and a rail may be necessary. Such screwing on and closing can also occur repeatedly in this case. For example, this can relate to the detachable connection between a double connector of the pressure regulator and a line. Then, when unscrewing or screwing the line onto the double connector, the further screw connection, namely between the double connector and the housing of the pressure regulator, can also be adjusted earlier or later. Loosening or undesired stronger tightening can lead to leaks and / or damage to the sealing elements, such as an O-ring or a flat gasket, which can also lead to a system leak with the escape of hydrogen. A bite edge can additionally, i.e. be pressed too strongly, into the sealing surface, so that leaks occur, or the bite edge is released or is released again after an excessively strong pressing, which likewise leads to leaks.Disclosure of the InventionThe connection according to the invention having the features of claim 1, the component according to the invention having the features of claim 10 and the fuel injection system according to the invention having the features of claim 11 have the advantage that an improved configuration and mode of operation are made possible. In particular, a material selection according to requirements can be made possible and / or leaks or the escape of gaseous fuel can be avoided. This is particularly true with respect to applications for blowing hydrogen.The measures set out in the dependent claims allow advantageous developments of the method specified in claim 1, of the component specified in claim 10 and of the fuel injection system specified in claim 11.It is advantageous that the friction welded connection is designed in the form of a continuous weld seam closed on a lateral surface of the connecting piece. This creates a free rotation prevention means. Additionally, a reliable seal can also be created.It is advantageous that the at least one friction welding connection is designed in the form of at least one welding point provided on a lateral surface of the connecting piece and / or that the friction welding connections are designed in the form of a plurality of preferably uniformly spaced and preferably completely encircling welding points provided on a lateral surface of the connecting piece. This creates a free rotation prevention means. In the case of a plurality of welding points, the anti-rotation device is particularly reliable. In the case of welding points, the friction-welded connection is realized by friction stir welding, because spot-type welded connections can be produced with friction stir welding. By means of friction welding, in which at least one welding partner is oscillated or rotated, in contrast, connections over the entire circumference can be realized in an advantageous manner.It is advantageous that the at least one friction welded connection is designed in the form of at least one weld seam segment provided on a lateral surface of the connecting piece and / or that the friction welded connections are designed in the form of a plurality of preferably uniformly spaced and preferably completely encircling weld seam segments provided on a lateral surface of the connecting piece. A high load capacity can thereby be ensured.It is advantageous that the stub of the second component has a thread with which the second component is screwed into a thread of the first component. As a result, for example, sealing via a bite edge and / or via a sealing element, in particular an O-ring or a flat seal, can be made possible. The friction welded connection can then optionally only serve as a non-rotational lock.It is advantageous that the bore of the first component has an inner side which is at least substantially in the form of a cylinder jacket, that the connector of the second component has an outer side which is at least substantially in the form of a cylinder jacket, and that the connector of the second component is connected on its outer side which is in the form of a cylinder jacket to the inner side of the first component in the form of a cylinder jacket by at least one friction welding connection. In this case, the friction welded connection can be configured flat, so that both a high sealing effect and a high mechanical load-bearing capacity can be produced.It is advantageous that the at least one friction welded connection is designed as a friction stir welded connection. This results in a very strong and secure welded connection.It is advantageous that the first component and the second component are formed from different materials, in particular a steel and an aluminum. Advantageous material combinations can thereby be realized. The friction welded connection or optionally a sealing element can ensure a reliable seal, so that corrosion processes between, for example, aluminum and steel can be prevented. In particular, the ingress of salt water is prevented.It is advantageous that at least one sealing element, in particular a sealing ring and / or a flat seal, is provided. By means of the friction welded connection, loosening or tightening too tightly can be prevented, so that the sealing via the sealing element is ensured over the service life.It is advantageous that the second component has a further connecting piece which has an external thread, and that the further connecting piece serves for a releasable screw connection provided on the external thread of the further connecting piece. In this way, in particular a line can be connected. The releasable screw connection can be designed, for example, for a 25 times loosening and re-tightening. The friction welded connection ensures the tightness of the connection between the first component and the second component, for example a housing and a screw-in connection piece, in particular a double connection piece.Depending on the configuration, at least one of the following features and / or advantages can be realized.In addition to the purpose of sealing, anti-rotation locking can also be realized by friction stir welding of the screw-in connection and the housing or rail. The following advantages can result from this. Sealing of the interface is possible. A free rotation prevention of the connecting piece can be achieved. If necessary, complicated and expensive geometries, such as a bite edge, can be dispensed with. Welding can be effected between different materials, in particular aluminum and steel.A screw-in connection can be screwed into the provided thread on the housing. The tightness can be achieved by the geometric use of a bite edge or by structural sealing elements, such as O-rings or flat seals. In addition, in a configuration particularly suitable for hydrogen applications, the screw-in connectors are additionally welded to the housing after the screw-in process by a friction stir welding method against unscrewing.In friction stir welding, the welding tool preferably has a high rotational speed. After the required rotational speed has been reached, the tool is pressed onto the connection point between the two materials. As a result of the rotational speed and the force exerted on the connecting point, a heat input is produced which leads to the melting of the materials. The rotation of the tool causes the two materials to be stirred together. This produces a very strong and secure welded connection.In contrast to conventional welding methods, the following advantages can be achieved by friction stir welding. Weld defects such as pores or cracks can be avoided. Different materials can be joined to one another. High strength of the weld can be achieved. Welding with a comparatively low heat input is possible.In addition to a continuous weld seam, which in this case preferably extends in a circular manner, it is also possible to set only one or more welding point(s). As a result, a free rotation prevention can furthermore be achieved, wherein a further sealing measure is then provided.A segment-shaped weld seam can also be realized accordingly.The proposed connection is especially suitable for hydrogen pressure regulators and hydrogen rails and comparable products with seals via screw-in connectors, in particular double connectors.In particular, advantageous refinements and advantages can also be achieved in the case of a double connector without a thread to the housing or the like.In this case, an advantageous sealing of the interface can take place. A free rotation prevention of the connecting piece during operation and service can be achieved. Damage to sealing elements in the event of service is prevented. If necessary, complicated and expensive geometries, such as a bite edge, can be dispensed with. Welding between different materials, e.g. aluminum and steel, is possible.A threaded socket may be replaced with simpler non-threaded sockets in hydrogen applications. These are welded to one another by the friction welding method, for example to the counterpart, such as the housing or rail. During friction welding, the welding tool, here for example the connecting piece, has a high rotational speed. After the required rotational speed has been reached, the tool is pressed onto the connection point between the two materials. The rotational speed and the force exerted on the connecting point result in a heat input which leads to the melting of the materials. The rotation of the tool causes the two materials to be stirred together. This produces a very strong and secure welded connection.By eliminating the thread, a smaller installation space and a saving in material can be achieved. No complicated sealing geometry, such as a bite edge, is required. Optionally, no preprocessing of the housing is necessary, such as, for example, the attachment of mirror-reflecting surfaces. A connection between different materials is possible, such as aluminum and steel. A fast and safe process can be realized. A configuration of the connection can be achieved which is secure against unscrewing during a service.In one possible embodiment, the connectors are connected to the housing or rail by a friction welding method. In comparison with screw-in connectors with bite edge, both the thread and the bite edge can be dispensed with. This simultaneously offers at least two advantages: firstly, a higher quality machining with regard to flatness in the bore base can be dispensed with. On the other hand, no internal stresses arise due to deformations which can be caused by bite edges.In the friction welding method, the connecting piece is rapidly rotated and gradually pressed or pressed onto the counterpart, here for example the housing or rail. As a result of the heat generated, the material is soft and the two workpieces can be connected to one another. By means of this method, it is possible to dispense with machining of the contact surface on the housing, for example, and to leave the latter in the original state. One reason for this is that the unevenness or more inaccurate perpendicularities can be melted away to a certain extent by the friction welding process. At the end, the positioning accuracy of the connecting piece is generally dependent on the installation accuracy. In contrast, in a conventional welding process, such as KE welding of the stubs from the high-pressure pump, machining of the contact surfaces is required before the welding process.Brief Description of the DrawingsPreferred exemplary embodiments of the invention are explained in more detail in the following description with reference to the attached drawings, in which corresponding elements are provided with corresponding reference numerals. The following are shown: FIG. 1 shows a fuel injection system with a fuel distributor for injecting gaseous fuels, in particular hydrogen, into combustion chambers of an internal combustion engine in a sectional schematic illustration according to a possible embodiment of the invention; FIG. 2 shows a connection between a first component and a second component of the fuel injection system shown in FIG. 1 in a separate schematic spatial illustration corresponding to a first exemplary embodiment of the invention; FIG. 3 shows the connection shown in FIG. 2 according to a second exemplary embodiment; FIG. 4 shows the connection shown in FIG. 2 according to a third exemplary embodiment; FIG. 5 shows a diagram for explaining a principle of friction welding according to a possible embodiment, and FIG. 6 shows a connection between a first component and a second component of the fuel injection system shown in FIG. 1 in a sectional, schematic, exploded view corresponding to a fourth exemplary embodiment, wherein a state during production is illustrated.Embodiments of the InventionFIG. 1 shows a fuel injection system 10 for injecting gaseous fuels, in particular hydrogen, into combustion chambers 11 of an internal combustion engine in a sectional schematic illustration corresponding to a possible embodiment of the invention. However, the fuel injection system 10 can also serve for other gaseous fuels, in particular for natural gas.The hydrogen is stored in liquid form under high pressure, for example about 700 bar (70 MPa), in a tank-like fuel storage 12. This can be filled via a filling connection 14. Furthermore, an integrated unit 16 comprising a tank valve for filling and discharging hydrogen into or from the fuel accumulator 12 and a temperature sensor for detecting the temperature of the gaseous hydrogen coming from the fuel accumulator 12 is arranged on the fuel accumulator 12.The gaseous hydrogen passes via a pressure line 18 first to a filter 20 and from there further to a high-pressure pressure pressure regulating device (high-pressure pressure regulator) 22, which reduces the pressure of the gaseous hydrogen, for example, to a pressure in the range of 40 bar (4 MPa). The pressure line 18 leads from the high-pressure pressure regulating device 22 further to a pressure sensor 24, a further filter 26 and an optional temperature regulating device 28 finally to a low-pressure pressure regulating unit (LP pressure regulator) 30.The low-pressure pressure regulating unit 30 comprises in the present case, by way of example, two hydraulically parallel pressure regulating valves 32, a low-pressure pressure sensor 34 and a safety valve in the form of a shut-off valve device 36. The pressure in the pressure line 18 is once again lowered by the low-pressure pressure regulating unit 30 from the pressure, which is exemplary at the input side, of approximately 40 bar (4 MPa) to a pressure, for example of approximately 15 bar (1.5 MPa).Downstream of the low-pressure pressure regulating unit 30, the pressure line 18 leads to a fuel distribution device 38, in particular rail 38, which can be designed, for example, as an elongate tube in the manner of a typical fuel rail, as is known from petrol and diesel fuel systems. The gas pressure prevailing in the fuel distribution device 38 is detected by a pressure sensor 40.A plurality of injectors 42 are connected to the fuel distribution device 38 and direct blow the gaseous hydrogen into the combustion chambers 11 of the internal combustion engine. The gaseous hydrogen is mixed with atmospheric oxygen in the combustion chambers 11 and this mixture is ignited by a respective ignition device 46. Typically, the internal combustion engine is a 2-stroke or 4-stroke piston internal combustion engine of a widely customary design. For example, such an internal combustion engine is used to drive a motor vehicle. However, it can also be used, for example, in a stationary manner for driving a generator for power generation.The fuel supply system 10 and its components are controlled by an electronic control and regulating device 48 which has one or more corresponding microprocessors, a memory for program code, etc. The control and regulating device 48 receives signals from, among other things, the temperature sensor (installed in the integrated unit 16), the pressure sensor 24, the pressure sensor 34, the pressure sensor 40, etc. The control and regulating device 48 controls various components of the fuel supply system 10, among other things, the low-pressure pressure pressure regulating device 30, the safety valve 36 and the ignition devices 46. Furthermore, a control device 50 is also controlled by the control and regulating device 48, which in turn specifically controls or regulates the operation of the fuel accumulator 12.FIG. 2 shows a connection 60 between a first component 61 and a second component 62 of the fuel injection system 10 shown in FIG. 1 in a separate schematic spatial illustration corresponding to a first exemplary embodiment. The connection 60 can be realized at several points 95 in the fuel injection system 10, which serves for injecting gaseous fuels, in particular hydrogen, into combustion chambers 11 of the internal combustion engine.For the purpose of illustration, a first component 61 of the fuel injection system 10 and a second component 62 of the fuel injection system 10 are considered to explain the connection 60. The first component 61 has a bore 63. The second component 62 has a connecting piece 64 which is inserted into the bore 62 of the first component 61. Furthermore, the second component 62 is connected at its connection piece 64 to the first component 61 by at least one friction-welded connection 65 formed by means of a friction-welding method.In this exemplary embodiment, exactly one friction welded connection 65 is preferably provided. The friction welded connection 65 is here formed in the form of a welded seam 69 which is closed on a circumferential surface 68 of the connecting piece 64 and preferably extends in a circular manner. Thus, anti-rotation and sealing are ensured.FIG. 3 shows the connection 60 illustrated in FIG. 2 according to a second exemplary embodiment. In this exemplary embodiment, a plurality of friction-welded connections 65 are provided, which are realized in the form of a plurality of welding points 70 provided on a lateral surface 68 of the connecting piece 64. The welding points 70 are uniformly spaced from one another in pairs. In addition, the welding points are arranged completely circumferentially. As a result, the welding points 70 can be arranged at equal angular distances over 360°.In a modified embodiment, however, only one or more welding points 70 can also be provided, which are arranged irregularly and / or not completely circumferentially.FIG. 4 shows the connection 60 illustrated in FIG. 2 according to a third exemplary embodiment. The friction welded connections 65 are designed in the form of a plurality of weld seam segments 71 provided on a lateral surface 68 of the connector 64, preferably uniformly spaced apart and preferably completely encircling.In a modified embodiment, however, only one or more weld seam segments 71 can also be provided, which are arranged irregularly and / or not completely circumferentially.FIG. 5 shows a diagram for explaining a principle of friction welding according to a possible embodiment. Steps S 1 to S 6 are shown here by way of example.In friction stir welding, the welding tool (tool) 72 has a high number of revolutions. After the required rotational speed has been reached, the tool 72 is pressed onto the connection point 73 between the two materials 74A, 74B (S 1). As a result of the rotational speed and the force exerted on the connecting point 73, a heat input is produced which leads to the melting of the materials 74A, 74B (S 2). By rotating the tool 72, the two materials 74A, 74B are stirred together (S 3). This produces a very strong and secure welded connection. Thus, a friction welded joint 65 may be formed as a friction stir welded joint 65.The tool 72 can be moved relative to the materials 74A, 74B (S 3 to S 4) so that, for example, a weld segment 71 is produced (S 5 and S 6).Materials 74A, 74B illustrate a friction welded joint 65 between first component 61 and second component 62. The first component 61 and the second component 62 may be made of different materials (materials) 74A, 74B. Specifically, they may be formed of steel and aluminum. In this case, in particular a component 61 serving as housing 79 can be formed from aluminium, while a second component 62 serving as double connector 81 can be formed from steel.FIG. 6 shows a connection corresponding to one of the exemplary embodiments shown in FIGS. 2 to 4 in a schematic sectional illustration. The connecting piece 64 of the second component 62 has a thread 75 with which the second component 62 is screwed into a thread 76 of the first component 61.Furthermore, at least one sealing element 80, in particular a sealing ring 80 and / or a flat seal 80, can be provided. Furthermore, the second component 62 has a further connection piece 85 with an external thread 86. This results in a double connecting piece 81 which has the connecting piece 64 and the further connecting piece 85. The further connector 85 can serve for a releasable screw connection provided on the external thread 86 of the further connector 85. The release lock ensures the initially defined loading of the sealing element 80 over the service life even when a line 18 is screwed on and off the further connector 85, for example, repeatedly.FIG. 7 shows a connection 60 between a first component 61 and a second component 62 of the fuel injection system 10 shown in FIG. 1 in a pull-out schematic sectional illustration corresponding to a fourth exemplary embodiment, wherein a state during production is illustrated.The bore 63 of the first component 61 has a cylinder jacket-shaped inner side 77. The connecting piece 64 of the second component 62 has a cylinder jacket-shaped outer side 78. The connecting piece 64 of the second component 62 is connected on its cylinder-jacket-shaped outer side 78 to the cylinder-jacket-shaped inner side 77 of the first component 61 by at least one friction welded connection 65.In this case, the connecting piece 64 of the second component 62 is formed without a thread. This is welded to the first component 61 by the friction welding method. During friction welding, the welding tool ( 72, FIG. 5 ), which is here, to a certain extent, the connecting piece 64, has a high rotational speed. After the required rotational speed has been reached, the tool 72 is pressed onto the connection point between the two materials 74A, 74B. As a result of the rotational speed and the force exerted on the connecting point 73, a heat input is produced which leads to the melting of the materials 74A, 74B. The rotation of the tool 72 causes the two materials 74A, 74B to be stirred together. This produces a very strong and secure welded connection.A component 90 of a fuel injection system 10, which serves for injecting gaseous fuels, in particular hydrogen, into combustion chambers 11 of an internal combustion engine, can thus be realized, wherein a first component 61 having a bore 63 and a second component 62 having a connecting piece 64 are provided, and wherein the second component 62 is connected at its connecting piece 64 to the first component 61 by a connection 60. Furthermore, a fuel injection system 10, which serves for injecting gaseous fuels, in particular hydrogen, into combustion chambers 11 of an internal combustion engine, can be realized, at least one such component 90 being provided.As is shown by way of example in FIG. 1, the connection 60 can be used in particular at the points 95. A plurality of devices of the fuel injection system 10 are suitable as component 90. Particularly preferably, the connection 60 is used on a pressure regulator 22, 30. The connection can be provided on the connection piece 54 of the low-pressure pressure regulator 30 and / or on the outlet-side connection piece 56 of the low-pressure regulator 30. The connection 60 can also be provided in particular on the integrated unit 16, on the filter 20, on the filter 26, if this is an individual element, and on the temperature control device 28. Particularly preferably, the connection 60 can additionally or alternatively be provided on the fuel distribution device 38, in particular rail 38.The invention is not limited to the described exemplary embodiments.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2006 040 236 A1 [0002, 0003]
Claims
Connection (60) for a fuel injection system (10) which serves for injecting gaseous fuels, in particular hydrogen, into combustion chambers (11) of an internal combustion engine, wherein a first component (61) of the fuel injection system (10) and a second component (62) of the fuel injection system (10) are provided, wherein the first component (61) has a bore (63), wherein the second component (62) has a stub (64) which is inserted into the bore (62) of the first component (61), and wherein the second component (62) is connected at its stub (64) to the first component (61), characterized in that the first component (61) and the stub (64) of the second component (62) are connected by at least one friction-welding connection (65) formed by means of a friction-welding method.Connection according to claim 1, characterised in that the friction welded connection (65) is formed in the form of a continuous welded seam (69) closed on a lateral surface (68) of the connecting piece (64).Connection according to claim 1 or 2, characterised in that a) the at least one friction welded connection (65) is formed in the form of at least one welding point (70) provided on a lateral surface (68) of the connecting piece (64) and / or that the friction welded connections (65) are formed in the form of a plurality of preferably uniformly spaced apart and preferably completely encircling welding points (70) provided on a lateral surface (68) of the connecting piece (64) and / or b) that the at least one friction welded connection (65) is formed in the form of at least one welding seam segment (71) provided on a lateral surface (68) of the connecting piece (64) and / or that the friction welded connections (65) are formed in the form of a plurality of preferably uniformly spaced apart and preferably completely encircling welding seam segments (71) provided on a lateral surface (68) of the connecting piece (64).Connection according to one of Claims 1 to 3, characterized in that the connecting piece (64) of the second component (62) has a thread (75), by means of which the second component (62) is screwed into a thread (76) of the first component (61).Connection according to claim 1, characterised in that the bore (63) of the first component (61) has an inner side (77) which is at least substantially in the form of a cylinder jacket, in that the connecting piece (64) of the second component (62) has an outer side (78) which is at least substantially in the form of a cylinder jacket, and in that the connecting piece (64) of the second component (62) is connected at its outer side (78) which is in the form of a cylinder jacket to the inner side (77) of the first component (61) which is in the form of a cylinder jacket by at least one friction-welding connection (65).Connection according to one of Claims 1 to 5, characterized in that the at least one friction-welded connection (65) is designed as a friction-stir welded connection (65).Connection according to one of Claims 1 to 6, characterized in that the first component (61) and the second component (62) are formed from different materials, in particular a steel and an aluminium.Connection according to one of Claims 1 to 7, characterized in that at least one sealing element (80), in particular a sealing ring (80) and / or a flat seal (80), is provided.Connection according to one of Claims 1 to 8, characterized in that the second component (64) has a further connecting piece (85) which has an external thread (86), and in that the further connecting piece (85) serves for a releasable screw connection provided on the external thread (86) of the further connecting piece (85).Component (90), in particular a pressure regulator (22, 30) or a fuel distribution device (38), of a fuel injection system (10) which serves for injecting gaseous fuels, in particular hydrogen, into combustion chambers (11) of an internal combustion engine, wherein a first component (61) having a bore (63) and a second component (62) having a connecting piece (64) are provided, and wherein the second component (62) is connected at its connecting piece (64) to the first component (61) by a connection (60) according to one of Claims 1 to 9.Fuel injection system (10) which serves for injecting gaseous fuels, in particular hydrogen, into combustion chambers (11) of an internal combustion engine, wherein at least one component (90) according to Claim 10 is provided.