EP2581462A1 - Blowing lance with direct ignition through retractable ignition lance - Google Patents

Abstract

The blast lance comprises an outer jacket (8), which extends along a blast lance longitudinal axis, where an oxygen guide runs within the outer jacket and comprises an oxygen exit (14) for emerging oxygen (6) at a blowing end of the lance. The oxygen exit is fed over an oxygen supply connection into the oxygen guide. A combustible gas guide runs within the outer jacket and comprises a number of combustible gas exits for emerging a combustible gas at the blowing end of the blast lance. The combustible gas exits are fed over a combustible gas supply connection into the combustible gas guide. The blast lance comprises an outer jacket (8), which extends along a blast lance longitudinal axis, where an oxygen guide runs within the outer jacket and comprises an oxygen exit (14) for emerging oxygen (6) at a blowing end of the blast lance. The oxygen exit is guided over an oxygen supply connection into the oxygen guide. A combustible gas guide runs within the outer jacket and comprises combustible gas exits for emerging a combustible gas at the blowing end of the blast lance. The combustible gas exits are guided over a combustible gas supply connection into the combustible gas guide. An ignition device: is arranged in the blast lance; comprises an ignition tip for igniting a combustible gaseous mixture; and is movable between its extended position and withdrawn position. The firing tip is affected in the extended position to a mixing region, in which the oxygen supplied to the oxygen exit and the combustible gas withdrawing at the combustible gas exits are mixed to the combustible gaseous mixture. The ignition device is withdrawn in the withdrawn position into a save area, in which the ignition device is protected before splashing a metal melt. The ignition device extends parallel to the blast lance longitudinal axis, and is parallely displaceable to the blast lance longitudinal axis. The firing tip of the ignition device extends in the extended position over the blowing end of the blast lance. The oxygen guide comprises a widening region. The ignition device is arranged beside the oxygen guide and extends in the extended position into the widening region. One of the combustible gas exits is arranged in the oxygen guide so that a mixing region is arranged within the oxygen guide. A passage for guiding the ignition device is opened over a lateral recess to the mixing region, and the firing tip of the ignition device is arranged in the extended position in an area of the recess. The firing tip of the ignition device is withdrawn in the withdrawn position from the mixing region. The ignition device: is flexed; helically extends around an ignition device longitudinal axis that runs parallel to the blast lance longitudinal axis in a constant distance to blast lance longitudinal axis; is formed in an arc-shaped manner; and is designed as an ignition lance, which generates spark ignition tip. An ignition apparatus is connected to the ignition lance, via a cable (26), for providing voltage pulses required to generate the ignition spark. The ignition apparatus is designed as capacitor-supply semiconductor ignition device. The save area is covered, in the withdrawn position of the ignition device to the mixing region, by a cover device.

Description

• wobei die Blaslanze einen Außenmantel aufweist, der sich entlang einer Blaslanzenlängsachse erstreckt,
• wobei innerhalb des Außenmantels eine Sauerstoffführung verläuft, die an einem Ausblasende der Blaslanze einen Sauerstoff-Austritt zum Austreten von Sauerstoff aufweist, welcher über einen Sauerstoff-Speiseanschluss in die Sauerstoffführung eingespeist wird,
• wobei innerhalb des Außenmantels eine Brenngasführung verläuft, die am Ausblasende der Blaslanze eine Anzahl von Brenngas-Austritten zum Austreten eines Brenngases aufweist, welches über einen Brenngas-Speiseanschluss in die Brenngasführung eingespeist wird,
• wobei in der Blaslanze eine Zündeinrichtung angeordnet ist, die eine Zündspitze zum Zünden eines brennbaren Gasgemisches aufweist.

The present invention relates to a lance for a molten metal vacuum treatment plant,

• wherein the lance has an outer sheath extending along a Blaslanzenlängsachse,
• wherein within the outer shell an oxygen guide extends, which has at an outlet end of the lance an oxygen outlet for the escape of oxygen, which is fed via an oxygen feed port into the oxygen guide,
• wherein within the outer shell a fuel gas duct extends, which has at the discharge end of the lance a number of fuel gas outlets for the escape of a fuel gas, which is fed via a fuel gas feed port into the fuel gas duct,
• wherein in the lance an ignition device is arranged, which has a firing tip for igniting a combustible gas mixture.

Such a lance is for example from the DE 10 2010 007 119 B3 known.

During the vacuum treatment of a molten metal, in particular a molten steel, oxygen is blown onto the molten metal. The oxygen is often applied to the molten metal by means of an oxygen lance.

Before the vacuum treatment, the vacuum vessel receiving the molten metal must be preheated. Again, the lance is often used. This is possible because in addition to the oxygen guide a fuel gas guide is present in the outer jacket of the lance and thus the lance can be used not only as an oxygen lance, but also as a fire lance.

In the conventional state of the art, the ignition of the ignitable gas mixture emerging from the lance takes place from oxygen and fuel gas by means of an additional, smaller burner (auxiliary burner, pilot burner). The pilot burner in turn is ignited by the igniter and the ignition lance through the sparks. Only the pilot flame of the pilot burner ignites the flame of the lance used as a fire lance.

In the conventional, also the DE 10 2010 007 119 B3 Underlying prior art, the pilot burner is arranged in the vicinity of the discharge end of the lance. The pilot burner is therefore exposed to the ambient conditions in which the lance is in total. When operating as an oxygen lance, this can lead to metal splashes or slag spatters getting into the pilot burner or to the pilot burner. Such splashes can lead to failure of the pilot burner and thus to a failure of the burner function of the lance. The lance must be time-consuming cleaned or replaced in such a case. In particular, the productivity loss occurring here and often also the thermal change of the molten metal during this time are disadvantageous.

To solve this problem is in the DE 10 2010 007 119 B3 proposed to arrange the pilot burner in an ignition chamber, which is arranged as such with respect to the vacuum vessel stationary and located at a sufficient distance from the molten metal.

The object of the present invention is to develop a lance of the type mentioned in such a way that in a simple and reliable way ignition of the resulting at the discharge end combustible mixture is possible.

The object is achieved by a lance with the features of claim 1. Advantageous embodiments of the invention Blow lance are the subject of dependent claims 2 to 13.

• dass die Zündeinrichtung zwischen einer ausgefahrenen Stellung und einer zurückgezogenen Stellung verfahrbar ist,
• dass die Zündspitze in der ausgefahrenen Stellung auf einen Mischbereich wirkt, in dem sich der dem Sauerstoff-Austritt zugeführte Sauerstoff und das an den Brenngas-Austritten austretende Brenngas zu einem zündfähigen Gasgemisch mischen, und
• dass die Zündeinrichtung in der zurückgezogenen Stellung in einen Schutzbereich zurückgezogen ist, in dem die Zündeinrichtung vor Spritzern der Metallschmelze geschützt ist.

According to the invention it is provided to design a lance of the type mentioned, characterized

• that the ignition device is movable between an extended position and a retracted position,
• in the extended position, the firing tip acts on a mixing region in which the oxygen supplied to the oxygen outlet and the fuel gas emerging at the fuel gas outlets mix to form an ignitable gas mixture, and
• that the ignition device is retracted in the retracted position into a protective area in which the ignition device is protected against splashes of the molten metal.

It is possible that the ignition device extends parallel to the Blaslanzenlängsachse and that the ignition device is displaceable parallel to the Blaslanzenlängsachse. This embodiment of the lance is particularly easy to implement.

If the ignition device is displaceable parallel to the Blaslanzenlängsachse, for example, the firing tip of the ignition device may protrude in the extended position on the discharge end of the lance and retracted in the retracted position behind the discharge end of the lance. In this case, an "external" ignition of the gas mixture, ie outside the lance.

In the case of an external ignition, it is possible that the ignition device is arranged next to the oxygen guide. Alternatively, if the oxygen guide has an expansion region at the discharge end, it is also possible for the ignition device to project into the widening region in the extended position.

If the oxygen guide at the discharge end has a widening region and the ignition device protrudes in the extended position in the widening region, it may also be possible that the firing tip of the ignition device in the extended position does not protrude beyond the discharge end of the lance. In this case, an "internal" ignition, so an ignition is still within the oxygen guide. Of course, in this case, at least one of the fuel gas exits must be arranged in the oxygen guide, so that the mixing region is still arranged within the oxygen guide.

If at least one of the fuel gas outlets is arranged in the oxygen guide, so that the mixing region is still arranged within the oxygen guide, it is also possible that a guide channel for guiding the ignition device is opened via a lateral recess to the mixing region and the firing tip of the ignition device is arranged in the extended position in the region of the recess. In this case, the ignition device is also protected in the extended position substantially before the radiant heat of the molten metal and the combustion flame of the lance.

The last-mentioned embodiment, ie the provision of a guide channel with a lateral recess towards the mixing region, can be realized independently of whether or not the oxygen guide has a widening region. However, it is preferred that the oxygen guide has the expansion area.

Furthermore, it is possible that the ignition device is bent. In this case, the firing tip of the ignition device in the extended position can easily protrude into the mixing region and be withdrawn from the mixing region in the retracted position.

The ignition device may, for example, extend helically around an ignition device longitudinal axis, the ignition device longitudinal axis extending parallel to the longitudinal axis of the blowing lance at a constant distance from the longitudinal axis of the lance of the lance. Alternatively, the ignition device may be formed in a circular arc.

It is possible that the ignition device is designed as a conventional pilot burner, at whose firing tip a flame ignites the combustible gas mixture. Preferably, however, the ignition device is designed as an ignition lance, whose firing tip generates sparks. In this case, an ignition device is connected to the ignition lance for providing voltage pulses necessary for the generation of the ignition spark. The ignitor can be designed, for example, as a capacitor-fed semiconductor ignition device.

Preferably, the ignitor is connected to the ignition lance via a cable. As a result, the ignitor does not have to be arranged inside the blow lance itself.

Preferably, the protected area in the retracted position of the ignition device is covered towards the mixing area by means of a covering device. As a result, the reliability of the ignition device is further optimized.

FIG 1

eine Vakuumbehandlungsanlage in einem ersten Betriebszustand,

FIG 2

die Vakuumbehandlungsanlage von FIG 1 in einem zweiten Betriebszustand,

FIG 3

eine Blaslanze im Längsschnitt in einem ersten Betriebszustand,

FIG 4

eine Zündeinrichtung,

FIG 5

eine Zündlanze und ein Zündgerät und

FIG 6 bis 16

Ausgestaltungen des Ausblasendes der Blaslanze von FIG 3 im Längsschnitt in verschiedenen Betriebszuständen.

The above-described characteristics, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following description of the embodiments, which will be described in more detail in conjunction with the drawings. Here are shown in a schematic representation:

FIG. 1

a vacuum treatment plant in a first operating state,

FIG. 2

the vacuum treatment plant of FIG. 1 in a second operating state,

FIG. 3

a lance in longitudinal section in a first operating state,

FIG. 4

an ignition device,

FIG. 5

an ignition lance and an ignition device and

FIGS. 6 to 16

Embodiments of the discharge end of the lance of FIG. 3 in longitudinal section in different operating states.

According to FIG. 1 has a vacuum treatment plant for a molten metal 1 - for example, a molten steel 1 - a melt container 2. In the melt container 2 is according to FIG. 1 the molten metal 1. The melt container 2 is covered by a dome-shaped hood 3. The hood 3 is connected to a take-off device (not shown in the FIG), so that the molten metal 1 is substantially adjacent to a vacuum at its top. In the in FIG. 1 shown operating state of the vacuum treatment plant is the molten metal 1 via a blowout 4 a blowgun 5 oxygen 6 is supplied. The oxygen 6 reacts with the molten metal 1. As part of the chemical reaction resulting gases and the unreacted oxygen content are sucked by means of the take-off device.

FIG. 2 shows the same vacuum treatment plant in a second operating state. In this operating state is located in the melt container 2 no molten metal. The melt container 2 can also be covered by the hood 3 in this operating state. Alternatively, he can be open. In this operating state, the melt container 2 is heated by means of a flame 7, which is generated at the discharge end 4 of the lance 5.

According to FIG. 3 the lance 5 has an outer jacket 8. The outer jacket 8 is generally cylindrical. It extends along a Blaslanzenlängsachse 9, which also represents a central axis 9 (= gravity axis 9) of the lance 5. The lance 5 thus extends along the Blaslanzenlängsachse. 9

The outer jacket 8 is usually water-cooled. For this purpose, it has a feed connection 10 and a discharge connection 11, via which cooling water 12 is supplied to the outer casing 8 and, after flowing through the outer casing 8, is discharged again from the outer casing 8.

Within the outer jacket 8 there is an oxygen guide 13. The oxygen guide 13 has an oxygen outlet 14 at the outlet end 4. At the oxygen outlet 14, the oxygen 6 exits, which is fed via an oxygen feed port 15 in the oxygen guide 13.

In general, the oxygen guide 13 runs on the Blaslanzenlängsachse 9. Furthermore, the oxygen guide 13 usually over a large part of the length of the lance 5 a constant cross-section. At the discharge end 4, however, the oxygen guide 13 often has a widening 16. In this area, the oxygen guide 13 widens conically. However, these embodiments, ie the arrangement of the oxygen guide 13 on the Blaslanzenlängsachse 9 and the presence of the widening 16, are not absolutely necessary.

Within the outer jacket 8 continues to run a fuel gas guide 17. The fuel gas guide 17 has at the discharge end 4 a number of fuel gas outlets 18. At the fuel gas outlets 18, a fuel gas 19 - for example, methane, propane, butane or a combustible process gas - leak, which is fed to a fuel gas feed port 20 in the fuel gas 17. In the minimum case, only a single fuel gas outlet 18 is present. In general, either a plurality of fuel gas outlets 18 are present or the fuel gas outlet 18 is formed as an annular gap.

The fuel gas outlets 18 may be arranged at the discharge end 4 adjacent to the oxygen outlet 14. In general, however, the fuel gas outlets 18 are arranged in the oxygen guide 13. In particular, at least one of the fuel gas outlets 18 as shown by FIG. 3 be arranged in the expansion region 16 of the oxygen guide 13.

The oxygen 6 supplied to the oxygen outlet 14 and the fuel gas 19 emerging at the fuel gas outlet 18 mix in a mixing region 21 to form a combustible and also ignitable gas mixture. The mixing area 21 may be as shown in FIG FIG. 3 still be disposed within the oxygen guide 13. In particular, the mixing region 21 can be arranged in the widening region 16 of the oxygen guide 13. Alternatively, the mixing region 21 - in particular in the event that the fuel gas outlets 18 are not arranged in the oxygen guide 13 - lie in front of the discharge end 4 of the lance 5.

The gas mixture is ignited by means of an ignition device 22, which is arranged in the lance 5 for this purpose. The ignition device 22 in turn has - see in particular FIG. 4 - A firing tip 23, by means of which the thermal energy required to ignite the gas mixture is generated locally. The ignition device 22 is in particular according to the illustration of FIG. 3 disposed within the outer shell 8.

According to the in FIG. 4 illustrated preferred embodiment, the ignition device 22 is formed as an ignition lance 22, the firing tip 23 generates spark 24. The voltage pulses required to generate the sparks 24 are provided by an ignitor 25, which is connected to the ignition lance 22 for this purpose. The connection between the ignition lance 22 and the ignitor 25 may be rigid. Preferably, however, the ignitor 25 is connected to the ignition lance 22 via a cable 26.

The ignitor 25 is preferably designed as a capacitor-fed semiconductor ignition device. The electrical construction is off FIG. 5 seen.

According to FIG. 5 the ignitor 25 is connected to a voltage source U, for example, the general power supply with - depending on the state - a rated voltage of 100 V, 110 V or 230 V and a mains frequency of 50 Hz or 60 Hz. The voltage supplied by the voltage source U is in a transformer 27 up-converted and rectified in a rectifier 28. If the voltage source U outputs a DC voltage, the transformer 27 is preceded by an inverter.

The rectified voltage is buffered in a capacitor unit 29. The capacitor unit 29 is a semiconductor switching device 30 downstream. The semiconductor switching device 30 in turn is - directly or via the cable 26 - connected to the ignition lance 22. The semiconductor switching device 30 may, for example, be realized on the basis of GTO thyristors (GTO = gate turn off) or on the basis of IGBTs (= insulated gate bipolar transistor).

With a suitable choice of ignitor 25 and ignition lance 22 a reliable generation of the spark 24 is ensured. This is true even if the firing tip 23 is dirty or covered with oil or grease. Suitable ignitors 25 and suitable ignition lances 22 are sold, for example, by DURAG GmbH, Hamburg, Germany.

The present invention is explained below in connection with an ignition device 22 designed as an ignition lance 22. However, corresponding embodiments are also possible in which the ignition device 22 is designed as a pilot burner.

The ignition lance 22 can be moved between an extended position and a retracted position. In the extended position, the firing tip 23 acts on the mixing region 21 with the ignition sparks 24 generated by it This position is the ignition lance 22 for igniting the combustible gas mixture.

In the retracted position, the ignition lance 22 is retracted into a protective region 31, in which the ignition lance 22 is protected against metal and slag splashes of the molten metal 1. Optionally, in the case that the ignition lance 22 is in the retracted position, the protection region 31 may be covered towards the mixing region 21 by means of a spring-loaded or forced-operated covering device 32. The ignition lance 22 is transferred after the ignition of the combustible gas mixture in the retracted position and remains there until a renewed ignition of the gas mixture is required.

The protection area 31 may be formed as needed. For example, the protection area 31 according to FIG. 6 be formed by a guide channel 33 which is adapted to the cross section of the ignition lance 22. It is even possible that the protection area 31 is completely open. In this case, the protection of the ignition lance 22 can simply result from the (compared to the extended position) greater distance of the ignition lance 22 and in particular the firing tip 23 of the molten metal 1.

The following will be in connection with the FIGS. 6 to 16 various embodiments of the invention lance 5 explained in more detail.

The FIGS. 6 to 16 In particular, they all show the oxygen guide 13 including the widening region 16. The presence of the widening region 16 is always preferred. However, it is only in conjunction with the embodiments of FIGS. 8 to 10 and 12 absolutely necessary.

The FIGS. 6 to 16 Furthermore, they all show the fuel gas guide 17 and the fuel gas outlets 18. In particular, they show a plurality of fuel gas outlets 18. However, this is not mandatory. Furthermore, they show that the fuel gas outlets 18 are arranged in the oxygen guide 13, more precisely at the beginning of the widening region 16. However, the arrangement of the fuel gas outlets 18 in the oxygen guide 13 is only in conjunction with the FIGS. 10 to 16 mandatory.

The FIGS. 6 to 16 continue to show all the guide channel 33 and - depending on the FIG - completely or partially arranged in the guide channel 33 ignition lance 22 including its firing tip 23 and the cable 26th

Finally, the show FIGS. 6 and 7 and 13 and 14, the cover 32. The cover 32 could also in the embodiments of FIGS. 8 to 12 as well as 15 and 16 exist. Alternatively, the cover 32 could also in the FIGS. 6 and 7 as well as 13 and 14 are omitted.

According to the FIGS. 6 to 9 the ignition lance 22 extends parallel to Blaslanzenlängsachse 9. The ignition lance 22 is parallel to the Blaslanzenlängsachse 9 slidably. The FIG. 6 and 8th show the ignition lance 22 in the retracted position, the FIG. 7 and 9 show the ignition lance 22 in the extended position.

According to the FIG. 7 and 9 extends the firing tip 23 of the ignition lance 22 in the extended position on the discharge end 4 of the lance 5 addition. In the retracted position, the entire ignition lance 22 - so also the firing tip 23 - according to the FIG. 6 and 8th withdrawn behind the discharge end 4.

In the embodiment of FIGS. 6 and 7 the ignition lance 22 is arranged next to the oxygen guide 13. Alternatively, the oxygen guide 13 according to the FIGS. 8 and 9 have the expansion region 16. In this case, the ignition lance 22 may be advanced over the expansion region 16.

If according to the representation of FIG. 8 the oxygen guide 13 has the widening region 16, it can continue - in contrast to FIG. 9 - be sufficient if the ignition lance 22 according to FIG. 10 protrudes in the extended position only in the expansion region 16, but does not protrude beyond the discharge end 4.

As explained above, the fuel gas outlets 18 are arranged - at least partially - in the oxygen guide 13. Due to this configuration, the mixing region 21 is likewise arranged-at least partially-in the oxygen guide 13. In this case, it can according to the FIG. 11 and 12 sufficient that the guide channel 33 has a lateral recess 34, via which the guide channel 33 is opened to the mixing region 21. In this case, it may be sufficient if the firing tip 23 of the ignition lance 22 is arranged in the extended position of the ignition lance 22 in the region of the lateral recess 34. It is particularly advantageous in this context when the firing tip 23 in accordance with the representation of FIG. 12 to the side recess 34 hinzeigt.

In the above, in conjunction with the FIGS. 6 to 12 explained embodiments, the ignition lance 22 is straight ("rod-shaped"). Alternatively, the ignition lance 22 according to the FIGS. 13 to 16 be bent. Here, the ignition lance 22 may be formed in a circular arc. The FIG. 13 and 14 show a corresponding ignition lance 22 in the retracted and the extended position. Alternatively, the ignition lance 22 may extend helically (helically) around an initiator longitudinal axis 35. The Zeiinrichtungslängsachse 35 is arranged in this case parallel to Blaslanzenlängsachse 9. It runs at a constant distance (offset) a to the lance longitudinal axis 9. The FIG. 15 and 16 show a corresponding ignition lance 22 in the retracted and the extended position.

According to the FIG. 14 and 16 the firing tip 23 of the ignition lance 22 projects into the mixing region 21 in the extended position. In the retracted position, the ignition lance 22 is in accordance with FIG. 13 and 15 withdrawn from the mixing area 21. The present invention has many advantages. In particular, an ignition of the (main) flame 7 of the lance 5 is possible in a simple and reliable manner, if this is to be used as a fire lance. Furthermore, omitted in the case of direct ignition, so a design of the ignition device 22 as the ignition lance 22, fuel gas and oxygen guides for the pilot burner required in the prior art. Control devices for the pilot burner are no longer necessary in this case.

While the invention has been further illustrated and described in detail by the preferred embodiment, the invention is not limited by the disclosed examples, and other variations can be derived therefrom by those skilled in the art without departing from the scope of the invention.

Claims (13)

Blowing lance for a molten metal vacuum treatment plant, - wherein the lance has an outer jacket (8) extending along a Blaslanzenlängsachse (9), - Wherein within the outer shell (8) an oxygen guide (13) extends at an outlet end (4) of the lance an oxygen outlet (14) for the escape of oxygen (6), which via an oxygen feed port (15) in the oxygen guide (13) is fed, - wherein within the outer shell (8) a fuel gas guide (17) extends at the Ausblasende (4) of the lance a number of fuel gas outlets (18) for exiting a fuel gas (19) which via a fuel gas feed port (20) is fed into the fuel gas duct (17), - Wherein an ignition device (22) is arranged in the lance, which has a firing tip (23) for igniting a combustible gas mixture, - wherein the ignition device (22) is movable between an extended position and a retracted position, - Wherein the firing tip (23) in the extended position on a mixing region (21) acts in which the oxygen outlet (14) supplied oxygen (6) and at the fuel gas outlets (18) emerging fuel gas (19) mix to the combustible gas mixture, - Wherein the ignition device (22) is retracted in the retracted position in a protective area (31), in which the ignition device (22) is protected against splashing of the molten metal (1). Blowing lance according to claim 1,
characterized in that the ignition device (22) extends parallel to Blaslanzenlängsachse (9) and that the ignition device (22) parallel to Blaslanzenlängsachse (9) is displaceable. Blowing lance according to claim 2,
characterized in that the firing tip (23) of the ignition device (22) protrudes in the extended position on the discharge end (4) of the lance and retracted in the retracted position behind the discharge end (4) of the lance. Blowing lance according to claim 3,
characterized in that the ignition device (22) is arranged next to the oxygen guide (13). Blowing lance according to claim 2 or 3,
characterized in that the oxygen guide (13) at the discharge end (4) has a widening region (16) and that the ignition device (22) protrudes in the extended position in the widening region (16). Blowing lance according to claim 2,
characterized in that at least one of the fuel gas outlets (18) in the oxygen guide (13) is arranged, so that the mixing region (21) is still within the oxygen guide (13) arranged that a guide channel for guiding the ignition device (22) is opened via a lateral recess (34) to the mixing region (21) and that the firing tip (23) of the ignition device (22) is arranged in the extended position in the region of the recess. Blowing lance according to claim 1,
characterized in that the ignition device (22) is bent, that the firing tip (23) of the ignition device (22) protrudes in the extended position in the mixing region (21) and in the retracted position from the mixing region (21) is withdrawn. Blowgun according to claim 7,
characterized in that the ignition device (22) extending helically around a Zündeinrichtungslängsachse (35) and that the Zeiinrichtungslängsachse (35) parallel to the Blaslanzenlängsachse (9) at a constant distance (a) to the Blaslanzenlängsachse (9). Blowgun according to claim 7,
characterized in that the ignition device (22) is formed in a circular arc. Blowing lance according to one of the above claims,
characterized in that the ignition device (22) is designed as an ignition lance (22), the firing tip (23) generates spark (24), and that the ignition lance (22) an ignitor (25) for providing for the generation of the spark ( 24) required voltage pulses is connected. Blowing lance according to claim 10,
characterized in that the ignitor (25) is designed as a capacitor-fed semiconductor ignition device (30). Blowing lance according to claim 10 or 11,
characterized in that the ignitor (25) is connected to the ignition lance (22) via a cable (26). Blowing lance according to one of the above claims,
characterized in that the protective area (31) in the retracted position of the ignition device (22) is covered towards the mixing area (21) by means of a covering device (32).

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