CN214700801U

CN214700801U - Flame adjustable type pilot burner

Info

Publication number: CN214700801U
Application number: CN202120816804.4U
Authority: CN
Inventors: 马凯; 伍锐; 夏杰; 杨帆; 黄瑞祥; 张庆
Original assignee: Beijing Lantron Dingxin Petrochemical Equipment Co ltd
Current assignee: Beijing Fujia Engineering Technology Co ltd
Priority date: 2021-04-20
Filing date: 2021-04-20
Publication date: 2021-11-12
Anticipated expiration: 2031-04-20

Abstract

The utility model relates to a flame adjustable type pilot burner, which comprises a gun barrel and an ignition needle, wherein the ignition needle and the gun barrel are arranged side by side and detachably connected on the gun barrel, one end of the gun barrel is provided with a gun head, and the other end of the gun barrel is provided with an air inlet nozzle; the barrel is provided with a mixing chamber at a position close to the air inlet nozzle, the mixing chamber is provided with an air hole, and an air adjusting mechanism matched with the air hole is arranged at a position close to the air inlet nozzle on the barrel. The utility model discloses a flame adjustable type pilot burner is through seting up the wind hole on the mixing chamber to set up the air adjusting mechanism on the barrel, under the certain circumstances of fuel tolerance, can adjust the amount of wind that combustion-supporting wind got into the mixing chamber through the air adjusting mechanism, thereby can adjust flame's shape and length, guarantee flame detector's accurate discernment, improved flame detection accuracy. In addition, because the air consumption of the pilot burner is small, the required intake is also small, adopt the utility model discloses an adjustment mechanism adjusts also more simply reliable.

Description

Flame adjustable type pilot burner

Technical Field

The utility model relates to an environmental protection waste gas administers the field, concretely relates to flame adjustable type pilot burner.

Background

In the environmental protection waste gas treatment field, adopt the direct combustion mode to handle the flow according to the waste gas characteristic, the combustor is entire system's core, and whether the combustor can decompose the operation that comes the gas direct influence follow-up device steadily, still can lead to exhaust emissions not up to standard. The burner is not always capable of stably operating. The pilot burner is used as a safe auxiliary for the operation of the burner, keeps pilot during the operation of the system, can stably ignite a main gun of the burner, and provides atmosphere for pyrolysis of waste gas. In a burner ignition procedure, an incandescent lamp flame can also participate in interlocking, and if the rigidity of the incandescent lamp flame is insufficient or the length of the incandescent lamp flame is not in a proper range, the ignition is failed due to the fact that the flame cannot be detected by a fire detector, and the system driving is influenced. Therefore, the invention of the flame adjustable type pilot burner is particularly important.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that the flame shape of the existing pilot burner can not be flexibly adjusted to lead to fire detection inaccurate, and the pilot burner with adjustable flame is provided.

The utility model provides an above-mentioned technical problem's technical scheme as follows: a flame adjustable type pilot burner comprises a gun barrel and an ignition needle, wherein the ignition needle is arranged side by side with the gun barrel and is detachably connected to the gun barrel, one end of the gun barrel is provided with a gun head, and the other end of the gun barrel is provided with an air inlet nozzle; the barrel is provided with a mixing chamber at a position close to the air inlet nozzle, the mixing chamber is provided with an air hole, and an air adjusting mechanism matched with the air hole is arranged at a position close to the air inlet nozzle on the barrel.

The utility model has the advantages that: the utility model discloses a flame adjustable type pilot burner is through seting up the wind hole on the mixing chamber to set up the air adjusting mechanism on the barrel, under the certain circumstances of fuel tolerance, can adjust the amount of wind that combustion-supporting wind got into the mixing chamber through the air adjusting mechanism, thereby can adjust flame's shape and length, guarantee flame detector's accurate discernment, improved flame detection accuracy. In addition, because the air consumption of the pilot burner is small, the required intake is also small, adopt the utility model discloses an adjustment mechanism adjusts also more simply reliable.

On the basis of the technical scheme, the utility model discloses can also do following improvement.

Furthermore, the air adjusting mechanism comprises an air adjusting ring, the air adjusting ring is axially movably arranged in the interval between the air inlet nozzle and the mixing chamber, and a plurality of air holes are formed in the end face, close to the air adjusting ring, of one end of the mixing chamber.

The beneficial effect of adopting the further scheme is that: through setting up the air regulation ring, the air regulation ring can be followed barrel axial displacement, and the air regulation ring is walked downwards, and the clearance between air regulation ring and the mixing chamber is just grow, and the air inlet is just more, otherwise just few.

Furthermore, the air adjusting mechanism comprises an air adjusting sleeve, the air adjusting sleeve is axially movably arranged on the side wall of the mixing chamber and is arranged at intervals with the side wall of the mixing chamber, and the side wall of the mixing chamber is provided with a plurality of air holes.

The beneficial effect of adopting the further scheme is that: the wind holes can also be arranged on the side wall of the mixing chamber, the quantity of the wind holes shielded by the wind adjusting sleeve is small, or the shielding area is small, so that more wind enters, and less wind enters otherwise.

Furthermore, the air adjusting mechanism comprises an air adjusting ring and an air adjusting sleeve, the air adjusting sleeve is sleeved outside the mixing chamber and is arranged at an interval with the mixing chamber, the air adjusting ring can be axially movably arranged in an interval between the air inlet nozzle and the mixing chamber, and one end of the air adjusting sleeve is connected with the air adjusting ring; the end face of one end of the mixing chamber close to the air adjusting ring or/and the side wall of the mixing chamber is/are provided with the air holes.

The beneficial effect of adopting the further scheme is that: the mode of combining the air adjusting ring and the air adjusting sleeve is adopted, so that the air quantity can be adjusted more flexibly.

Furthermore, the aperture of the air holes is phi 4 mm-phi 12mm, and the number of the air holes is 4-16.

The beneficial effect of adopting the further scheme is that: the air inlet is adjusted more stably and reliably by reasonably limiting the aperture and the number of the air holes.

Furthermore, a plurality of inclined spray holes are formed in the position, close to the gun head, of the side wall of the gun head of the gun barrel; the inclined spray holes are arranged in a plurality of circles at intervals along the axial direction of the gun barrel, and each circle of inclined spray holes are arranged at intervals along the circumferential direction of the gun barrel; the gun head end face of the gun barrel is further provided with a plurality of horizontal holes, and each horizontal hole penetrates through a corresponding inclined jet hole.

The beneficial effect of adopting the further scheme is that: through set up multi-angle slant orifice on the rifle head, flame combustion intensity is high, and rifle head up end sets up many horizontal holes, plays the effect of stable combustion.

Furthermore, the included angle between each circle of the inclined spray holes and the axial direction of the gun barrel is the same; and the included angle between each circle of the inclined spray holes and the axial direction of the gun barrel is sequentially increased or decreased along the direction close to the end surface of the gun head.

The beneficial effect of adopting the further scheme is that: further improving the flame burning intensity.

Furthermore, the included angle between the inclined spray hole and the axial direction of the gun barrel is 22.5-60 degrees.

Further, the gun tube is welded on the mounting flange, and the ignition needle is in threaded connection with the mounting flange; the mounting flange is in threaded connection with a sleeve, one end of the sleeve, which is far away from the gun head, is arranged, and the sleeve is sleeved outside the gun barrel and one end of the ignition needle.

The beneficial effect of adopting the further scheme is that: the gun tube is welded on the mounting flange, and the ignition needle is in threaded connection with the mounting flange, so that the gun tube can be integrally disassembled and replaced. The sleeve is connected with the mounting flange through the bolt, insulating paint is coated on the inner wall of the sleeve, the cable in the sleeve is protected, and electric leakage is prevented.

Furthermore, a plurality of ignition needle fixing pieces which are arranged along the axial direction of the gun barrel are welded on the gun barrel, a positioning hole and a locking threaded hole are formed in each ignition needle fixing piece, the ignition needles penetrate through the plurality of ignition needle fixing pieces through the positioning holes and are connected in the locking threaded hole through bolt threads to tightly support the ignition needles. The positioning hole and the locking threaded hole can be vertically arranged.

The beneficial effect of adopting the further scheme is that: the ignition needle fixing piece is welded with the torch tube of the pilot burner, and the ignition needle is tightly fixed on the torch tube through the bolt, so that the ignition needle is convenient to disassemble. The torch head of the beacon light is connected to the torch tube through threads, and is easy to detach and replace compared with welding.

Drawings

Fig. 1 is a schematic front view of the flame adjustable incandescent lamp of the present invention;

FIG. 2 is an enlarged view of portion A of FIG. 1;

FIG. 3 is a schematic sectional view of the lance tip;

FIG. 4 is a schematic top view of the lance tip;

fig. 5 is a schematic front view of another embodiment of the flame adjustable incandescent lamp of the present invention.

In the drawings, the components represented by the respective reference numerals are listed below:

1. a barrel; 11. an air inlet nozzle; 12. a mixing chamber; 13. a wind adjusting ring; 14. a wind adjusting sleeve; 2. an ignition needle; 3. a gun head; 31. a first inclined jet hole; 32. a second inclined jet hole; 33. a horizontal hole; 4. installing a flange; 5. a sleeve; 6. an ignition needle fixing member; 61. and (4) bolts.

Detailed Description

The principles and features of the present invention are described below in conjunction with the following drawings, the examples given are only intended to illustrate the present invention and are not intended to limit the scope of the present invention.

Example 1

As shown in fig. 1-4, the flame adjustable type pilot burner of the present embodiment includes a barrel 1 and an ignition needle 2, where the ignition needle 2 is arranged side by side with the barrel 1 and detachably connected to the barrel 1, one end of the barrel 1 is provided with a burner head 3, and the other end is provided with an air inlet nozzle 11; a mixing chamber 12 is arranged at the position of the gun barrel 1 close to the air inlet nozzle 11, an air hole is formed in the mixing chamber 12, and an air adjusting mechanism matched with the air hole is arranged at the position of the gun barrel 1 close to the air inlet nozzle 11.

As shown in fig. 1, the air adjusting mechanism includes an air adjusting ring 13, the air adjusting ring 13 is axially movably disposed in an interval between the air inlet nozzle 11 and the mixing chamber 12, and a plurality of air holes are opened on an end surface of the mixing chamber 12 close to the air adjusting ring 13. Through setting up the air regulation ring, the air regulation ring can be followed barrel axial displacement, and the air regulation ring is walked downwards, and the clearance between air regulation ring and the mixing chamber is just grow, and the air inlet is just more, otherwise just few. Specifically, the air adjusting ring 13 may be screwed to the barrel 1, and the air volume may be adjusted by rotating the air adjusting ring 13.

The aperture of the wind holes is phi 4 mm-phi 12mm, and the number of the wind holes is 4-16. The air inlet is adjusted more stably and reliably by reasonably limiting the aperture and the number of the air holes.

As shown in fig. 1 to 4, a plurality of inclined spray holes are formed in a position, close to a gun head 3, of a side wall of the gun head 3 of the gun barrel 1 according to the embodiment; the inclined spray holes are arranged in a plurality of circles at intervals along the axial direction of the gun barrel 1, and each circle of inclined spray holes are arranged at intervals along the circumferential direction of the gun barrel 1; the gun head end face of the gun barrel 1 is further provided with a plurality of horizontal holes 33, and each horizontal hole 33 penetrates through a corresponding inclined jet hole. Through set up multi-angle slant orifice on the rifle head, flame combustion intensity is high, and rifle head up end sets up many horizontal holes, plays the effect of stable combustion.

As shown in fig. 3, the included angle between each circle of the inclined spray holes and the axial direction of the barrel 1 is the same; and along the direction close to the end surface of the gun head 3, the included angles between the inclined spray holes and the gun barrel 1 in the axial direction are sequentially increased or decreased. Further improving the flame burning intensity.

As shown in fig. 3, the inclined nozzle hole forms an angle of 22.5 ° to 60 ° with the axial direction of the barrel 1. As an alternative to this embodiment, as shown in fig. 1 and fig. 3, the lance tip 3 of this embodiment has two circles of inclined nozzle holes, which are a first inclined nozzle hole 31 and a second inclined nozzle hole 32. The angle between two first inclined nozzle holes 31 arranged symmetrically is a, a may be 120 °, the angle between two second inclined nozzle holes 32 arranged symmetrically is b, b may be 60 °.

As shown in fig. 1, the gun barrel 1 is welded to a mounting flange 4, and the ignition needle 2 is screwed to the mounting flange 4; the mounting flange 4 is in threaded connection with a sleeve 5, one end of the sleeve 5, which is far away from the gun head 3, is arranged, and the sleeve 5 is sleeved on the outer sides of the gun barrel 1 and one end of the ignition needle 2. The gun tube is welded on the mounting flange, and the ignition needle is in threaded connection with the mounting flange, so that the gun tube can be integrally disassembled and replaced. The sleeve is connected with the mounting flange through the bolt, insulating paint is coated on the inner wall of the sleeve, the cable in the sleeve is protected, and electric leakage is prevented.

As shown in fig. 1, a plurality of ignition needle fixing pieces 6 arranged along the axial direction of the gun barrel 1 are welded on the gun barrel 1, a positioning hole and a locking threaded hole are formed in each ignition needle fixing piece 6, and the ignition needle 2 penetrates through the plurality of ignition needle fixing pieces 6 through the positioning hole and is connected in the locking threaded hole through a bolt 61 in a threaded manner to tightly support the ignition needle 2. The positioning hole and the locking threaded hole can be vertically arranged. The ignition needle fixing piece is welded with the torch tube of the pilot burner, and the ignition needle is tightly fixed on the torch tube through the bolt, so that the ignition needle is convenient to disassemble. The torch head of the beacon light is connected to the torch tube through threads, and is easy to detach and replace compared with welding.

The adjustable pilot burner of flame of this embodiment is through seting up the wind hole on the mixing chamber to set up the air regulating mechanism on the barrel, under the certain circumstances of fuel tolerance, can adjust the amount of wind that combustion-supporting wind got into the mixing chamber through the air regulating mechanism, thereby can adjust the shape and the length of flame, guarantee the accurate discernment of flame detector, improved flame detection accuracy. In addition, because the air consumption of the pilot burner is small, the required intake is also small, adopt the utility model discloses an adjustment mechanism adjusts also more simply reliable.

The ignition process of the flame adjustable pilot burner in the embodiment includes that firstly, fuel gas with a certain pressure is sent into the pilot burner from the air inlet nozzle, then, power is supplied to the ignition needle through an external high-voltage cable, the head of the ignition needle generates electric sparks to the gun head to ignite the fuel gas, and the pilot burner is ignited. After the pilot burner is ignited, the position of the air adjusting ring is adjusted to control the amount of air entering the gun barrel, so that the flame length of the pilot burner is changed, and the flame can be accurately detected by fire detection.

Example 2

As shown in fig. 1 to 5, the flame adjustable type pilot burner of the present embodiment includes a barrel 1 and an ignition needle 2, wherein the ignition needle 2 is arranged side by side with the barrel 1 and detachably connected to the barrel 1, one end of the barrel 1 is provided with a burner head 3, and the other end of the barrel 1 is provided with an air inlet nozzle 11; a mixing chamber 12 is arranged at the position of the gun barrel 1 close to the air inlet nozzle 11, an air hole is formed in the mixing chamber 12, and an air adjusting mechanism matched with the air hole is arranged at the position of the gun barrel 1 close to the air inlet nozzle 11.

As shown in fig. 5, the air adjusting mechanism of the present embodiment includes an air adjusting sleeve 14, the air adjusting sleeve 14 is axially movably disposed on the sidewall of the mixing chamber 12 and spaced from the sidewall of the mixing chamber 12, and the sidewall of the mixing chamber 12 is provided with a plurality of air holes. The air holes can also be arranged on the side wall of the mixing chamber 12, and the air adjusting sleeve 14 has less shielding air holes or small shielding area, so that more air is supplied, and vice versa. Specifically, the air adjustment sleeve 14 may be screwed to the mixing chamber 12, and the air volume may be adjusted by rotating the air adjustment sleeve 14.

As shown in fig. 1 to 5, a plurality of inclined spray holes are formed in a position, close to a gun head 3, of a side wall of the gun head 3 of the gun barrel 1 according to the embodiment; the inclined spray holes are arranged in a plurality of circles at intervals along the axial direction of the gun barrel 1, and each circle of inclined spray holes are arranged at intervals along the circumferential direction of the gun barrel 1; the gun head end face of the gun barrel 1 is further provided with a plurality of horizontal holes 33, and each horizontal hole 33 penetrates through a corresponding inclined jet hole. Through set up multi-angle slant orifice on the rifle head, flame combustion intensity is high, and rifle head up end sets up many horizontal holes, plays the effect of stable combustion.

The ignition process of the flame adjustable pilot burner in the embodiment includes that firstly, fuel gas with a certain pressure is sent into the pilot burner from the air inlet nozzle, then, power is supplied to the ignition needle through an external high-voltage cable, the head of the ignition needle generates electric sparks to the gun head to ignite the fuel gas, and the pilot burner is ignited. After the pilot burner is ignited, the position of the air adjusting sleeve is adjusted to control the amount of air entering the gun barrel, so that the flame length of the pilot burner is changed, and the flame can be accurately detected by fire detection.

Example 3

Referring to fig. 1 and 5, the air regulating mechanism of the present embodiment includes an air regulating ring 13 and an air regulating sleeve 14, the air regulating sleeve 14 is sleeved outside the mixing chamber 12 and is arranged at an interval with the mixing chamber 12, the air regulating ring 13 is axially movably disposed in an interval between the air inlet nozzle 11 and the mixing chamber 12, and one end of the air regulating sleeve 14 is connected to the air regulating ring 13; the end surface of one end of the mixing chamber 12 close to the air adjusting ring 13 or/and the side wall of the mixing chamber 12 is provided with the air hole. The connection of the wind adjusting ring 13 can refer to fig. 1, and the structure of the wind adjusting sleeve 14 can refer to fig. 5. The mode of combining the air adjusting ring and the air adjusting sleeve is adopted, so that the air quantity can be adjusted more flexibly. Specifically, the air adjusting ring 13 may be screwed to the barrel 1, and the air volume may be adjusted by rotating the air adjusting ring 13.

The ignition process of the flame adjustable pilot burner in the embodiment includes that firstly, fuel gas with a certain pressure is sent into the pilot burner from the air inlet nozzle, then, power is supplied to the ignition needle through an external high-voltage cable, the head of the ignition needle generates electric sparks to the gun head to ignite the fuel gas, and the pilot burner is ignited. After the pilot burner is ignited, the air quantity entering the gun barrel is controlled by adjusting the positions of the air adjusting ring and the air adjusting sleeve, the flame length of the pilot burner is changed, and the flame can be accurately detected by fire detection.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship indicated based on the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

In the present application, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art without departing from the scope of the present invention.

Claims

1. A flame adjustable type pilot burner is characterized by comprising a gun barrel and an ignition needle, wherein the ignition needle is arranged side by side with the gun barrel and is detachably connected to the gun barrel, one end of the gun barrel is provided with a gun head, and the other end of the gun barrel is provided with an air inlet nozzle; the barrel is provided with a mixing chamber at a position close to the air inlet nozzle, the mixing chamber is provided with an air hole, and an air adjusting mechanism matched with the air hole is arranged at a position close to the air inlet nozzle on the barrel.

2. The flame adjustable incandescent lamp of claim 1, wherein the air adjusting mechanism comprises an air adjusting ring, the air adjusting ring is axially movably disposed in a space between the air inlet nozzle and the mixing chamber, and a plurality of air holes are formed in an end surface of the mixing chamber, which is close to the air adjusting ring.

3. The flame adjustable type incandescent lamp of claim 1, wherein the air adjusting mechanism comprises an air adjusting sleeve, the air adjusting sleeve is axially movably disposed on the side wall of the mixing chamber and spaced from the side wall of the mixing chamber, and the side wall of the mixing chamber is provided with a plurality of air holes.

4. The flame adjustable type incandescent lamp of claim 1, wherein the air adjusting mechanism comprises an air adjusting ring and an air adjusting sleeve, the air adjusting sleeve is sleeved outside the mixing chamber and is arranged at a distance from the mixing chamber, the air adjusting ring is axially movably arranged in a space between the air inlet nozzle and the mixing chamber, and one end of the air adjusting sleeve is connected with the air adjusting ring; the end face of one end of the mixing chamber close to the air adjusting ring or/and the side wall of the mixing chamber is/are provided with the air holes.

5. The flame adjustable incandescent lamp as claimed in any one of claims 1 to 4, wherein the aperture of the wind holes is from 4mm to 12mm, and the number of the wind holes is from 4 to 16.

6. The flame adjustable type beacon light of any one of claims 1 to 4, wherein the side wall of the head of the gun barrel near the nozzle is provided with a plurality of inclined spray holes; the inclined spray holes are arranged in a plurality of circles at intervals along the axial direction of the gun barrel, and each circle of inclined spray holes are arranged at intervals along the circumferential direction of the gun barrel; the gun head end face of the gun barrel is further provided with a plurality of horizontal holes, and each horizontal hole penetrates through a corresponding inclined jet hole.

7. The flame adjustable incandescent lamp of claim 6, wherein each ring of the inclined nozzle holes has the same angle with the axial direction of the barrel; and the included angle between each circle of the inclined spray holes and the axial direction of the gun barrel is sequentially increased or decreased along the direction close to the end surface of the gun head.

8. The flame adjustable incandescent lamp of claim 6, wherein the angle between the inclined nozzle hole and the axial direction of the barrel ranges from 22.5 ° to 60 °.

9. The flame adjustable incandescent lamp as claimed in any one of claims 1 to 3, wherein the barrel is welded to a mounting flange, and the ignition pin is screwed to the mounting flange; the mounting flange is connected with a sleeve in a threaded mode, one end, far away from the gun head, of the sleeve is arranged, the sleeve is sleeved on the outer sides of the gun barrel and one end of the ignition needle, and insulating paint is coated on the inner wall of the sleeve.

10. The flame adjustable type pilot burner as claimed in any one of claims 1 to 3, wherein a plurality of ignition needle fixing pieces are welded on the barrel and arranged along the axial direction of the barrel, the ignition needle fixing pieces are provided with positioning holes and locking threaded holes, the ignition needle penetrates through the plurality of ignition needle fixing pieces through the positioning holes and is connected in the locking threaded holes through bolts in a threaded manner to jack the ignition needle tightly.