JP2913200B2 - Spark rod - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Object of the Invention [Industrial Application Field] The present invention relates to a flame stabilizer formed of a conductive ceramic material and connected to an open end of a bottomed cylindrical metal pipe. A spark rod for a radiant tube that is projected into the combustion space of the radiant tube and generates a spark discharge in order to maintain the combustion of the combustion gas, particularly, at a base end of a spark rod body formed of a conductive ceramic material. The present invention relates to a spark rod in which an attached joint member is detachably attached to a tip portion of a spark rod holder.

[Prior Art] Conventionally, as this kind of spark rod, a spark rod entirely formed of a metal conductor such as an iron-chromium-aluminum alloy (for example, "Kanthal" manufactured by Gadelius) has been proposed. .

[Problems to be Solved] However, in the conventional spark rod, since the whole is formed by a metal conductor such as an iron-chromium-aluminum-based alloy, the amount of heat generated by combustion of the combustion gas increases. As the temperature of the radiant tube or the combustion furnace becomes higher, there is a disadvantage that (i) deterioration such as wear due to oxidation or curvature due to creep increases in a short time, and (ii) durability. There is a drawback that the service life is shortened, and (iii) there is a drawback that the whole must be replaced upon deterioration such as wear due to oxidation or curvature due to creep, and the material efficiency cannot be improved.

Accordingly, the present invention provides a spark rod in which a spark rod body formed of a conductive ceramic material is detachably attached to a spark rod holder formed of a tough metal conductor in order to eliminate these disadvantages. It will not be provided.

(2) Configuration of the Invention [Means for Solving the Problems] The means for solving the problems provided by the present invention is a solution that is formed of a conductive ceramic material and connected to the open end of a bottomed cylindrical metal pipe. A spark rod for a radiant tube, which protrudes into a combustion space of a flame device and generates a spark discharge, is formed of: (a) a conductive ceramic material, a tip of which protrudes into a combustion space of a flame stabilizer. (B) a plurality of combustion gas supply holes (13a) formed in a disk-shaped peripheral portion formed of a conductive ceramic material, and an inner peripheral surface of a substantially intermediate portion of the flame stabilizer; And the spark rod body (3) is inserted in the center holding hole (13b).
A holding part (13) for holding 1) via an insulating layer (14), and (C) a joint made of a conductive metal, wherein a base end of the spark rod body (31) is attached by insertion. A member (32); and (d) a metal conductor, the tip of which is detachably attached to the joint member (32) by screwing, and the base end of which is at the center of the base of the metal pipe. A spark rod holder (33) attached by an attachment member (35) via an insulating layer (34) and having a base end connected to a power source. is there.

[Operation] The spark rod according to the present invention is, as specified in the above [Means for Solving the Problems], a conductive metal to which a base end portion of a spark rod body formed of a conductive ceramic material is attached by insertion. (I) the amount of heat generated due to combustion of the combustion gas increases and deteriorates even when the temperature rises due to the increase in the amount of heat generated by the combustion of the combustion gas. And (ii) extend the useful life.

The spark rod according to the present invention also has the above-described configuration. (Iii) Electrical, thermal, and mechanical connection between the spark rod body made of a conductive ceramic material and the spark rod holder made of a metal conductor (Iv) Partial replacement is possible at the time of deterioration to improve material efficiency.

In addition, the spark rod according to the present invention has a structure in which the spark rod main body is supported by the holding portion and the spark rod holder is supported by the mounting member. It functions to suppress vibration of the part and prevent damage.

Embodiment Next, a preferred embodiment of a spark rod according to the present invention will be described in detail with reference to the accompanying drawings. Here, an example of a flame stabilizer to which the spark rod according to the present invention is attached will be described in order to facilitate understanding of the configuration and the operation and effect of the spark rod according to the present invention.

(Configuration of Embodiment) First, the configuration of an embodiment of a spark rod according to the present invention will be described in detail with reference to FIG.

Reference numeral 30 denotes a spark rod according to the present invention, which is formed of a conductive ceramic material and has a tip 31a.
Is formed by an appropriate heat-resistant metal conductor (for example, a heat-resistant alloy or stainless steel) having a spark rod body 31 functioning as a discharge region and a base end 31b of the spark rod body 31 attached to one end by insertion. The joint member 32 and the other end of the joint member 32, the tip of which is detachably attached by screwing and formed of a high-toughness metal conductor (for example, stainless steel, copper or brass). The spark rod holder 33, the insulating layer 34 disposed on the peripheral surface near the base end 33b of the spark rod holder 33, and the metal pipe 20 which is disposed around the insulating layer 34 and is described later. It has a mounting member 35 for appropriately mounting, and a power supply terminal 36 formed on the base end 33b of the spark rod holder 33 for connecting a power supply line (not shown).

Reference numeral 10 denotes a flame holder to which the spark rod 30 according to the present invention is attached, which is formed of a conductive ceramic material and is attached to an opening end of a metal pipe 20 described later; It has a combustion part 12 formed of a material and formed integrally with the cylindrical base 11, and a holding part 13 formed of a conductive ceramic material and formed integrally with the cylindrical base 11. ing.

The cylindrical base 11 of the flame stabilizer 10 is inserted and attached at one end 11A to an opening end 21A of a metal pipe main body 21 included in a metal pipe 20 described later. The combustion gas (for example, natural gas) provided from the end 21A is guided toward the other end 11B.

In the cylindrical base 11, the thickness of the one end 11A is reduced as desired. One end 11A of the cylindrical base 11 is inserted into the open end 21A of the metal pipe main body 21 and, when inserted and attached, engages the tip of the fixing screw 22 to stabilize the peripheral surface. At least one locking recess (which may be a locking hole) 11a is formed. A buffer member 11b such as a copper film may be arranged on the peripheral surface of the one end 11A of the tubular base 11 as required for the purpose of stabilizing the fixing by the tip of the fixing screw 22. At one end 11A of the tubular base 11, adhesive layers 11c and 11d made of a heat-resistant adhesive are provided within a range that does not block a conductive path between the metal pipe main body 21 and a heat-resistant adhesive. It may be formed.

The combustion portion 12 of the flame stabilizer 10 is connected to the other end portion 11B of the cylindrical base 11, and combustion gas is burned in an internal space (also referred to as a combustion space). The combustion section 12 has at least one connection with a connection section to the other end section 11B of the cylindrical base section 11.
Two auxiliary agent supply holes 12a are formed. Combustion agent supply hole 1
When a plurality of 2a are formed, they are preferably held at equal angular intervals.

The holding portion 13 of the flame stabilizer 10 is provided continuously with the inner peripheral surface of the other end portion 11B of the cylindrical base portion 11, and supplies the combustion gas to the peripheral portion thereof toward the internal space of the combustion portion 12. An appropriate number of combustion gas supply holes 13a are formed at desired angular intervals for holding the tip of the spark rod 30 according to the present invention, that is, the spark rod body 31 at the center via the insulating layer 14. Holding hole 13b.

The metal pipe 20 has a bottomed cylindrical shape, and has one end 11A of the cylindrical base 11 of the flame stabilizer 10 inserted and attached to the opening end 21A, and the opening of the metal pipe body 21. When screwed into a screw hole 21a formed on the peripheral surface of the end 21A, the tip presses the cushioning member 11b to engage the locking recess 11a, and the base 21B of the metal pipe main body 21. And a spark gas supply pipe 23 for supplying combustion gas from a combustion gas supply source (not shown), and a spark pipe according to the present invention, which is formed with respect to a base 21B of the metal pipe main body 21. It has a mounting hole 24 for mounting the mounting member 35 of the rod 30 appropriately (for example, by screwing).

After the spark rod body 31 of the spark rod 30 according to the present invention is extended through the internal space of the cylindrical base 11 of the flame stabilizer 10 , the tip 31a of the spark rod main body 31 has the internal space of the combustion part 12 (that is, the combustion space). Projected against

(Assembly Procedure) Further, an assembly procedure of an embodiment of the spark rod according to the present invention will be briefly described with reference to FIG.

The spark rod 30 according to the present invention is formed, for example, by winding an active metal braze onto the base end 31 of the spark rod body 31.
The joint member 32 is mounted by inserting b into one end of the joint member 32 and performing heat treatment. After that, the other end of the joint member 32 is connected to the tip 33a of the spark rod holder 33. On the peripheral surface of the base end portion 33b of the spark rod holder 33, a mounting member 35 is previously disposed via an insulating layer 34.

The flame stabilizer 10 has a heat-resistant adhesive (hereinafter referred to as a heat-resistant adhesive) in which a buffer member 11b is disposed on the peripheral surface of one end 11A of the cylindrical base 11 and leakage of the combustion gas is prevented from the distal end surface and the step end surface. This forms the adhesive layers 11c and 11d) and is inserted into the open end 21A of the metal pipe main body 21 in a state where it is arranged.

By screwing the fixing screw 22 into the screw hole 21a of the metal pipe main body 21, the tip of the fixing screw 22 presses the buffer member 11b and engages with the locking recess 11a.

After that, the spark rod 30 according to the present invention is inserted into the mounting hole 24 of the metal pipe 20 from its distal end portion, that is, the distal end portion 31a of the spark rod main body 31, and the holding portion formed on the holding portion 13 of the flame stabilizer 10 is held. Insert into hole 13b. After that, the mounting member 35 is appropriately mounted to the mounting hole 24.

As described above, the spark rod 30 according to the present invention is attached to the flame stabilizer 10 .

(Operation of Embodiment) In addition, the operation of an embodiment of the spark rod according to the present invention will be described in detail with reference to FIG.

Flame holder 10, the guided combustion gas as shown by an arrow A ₂ after being fed as indicated by arrow A ₁ from the combustion gas supply by the combustion gas supply pipe 23, the opening end 21A of the metal pipe body 21 After guide to the holding member 13 by the receiving tubular base portion 11, supplied to the combustion space of the combustion section 12 as shown by arrow a ₃ via the combustion gas supply hole 13a formed in the peripheral edge portion of the holding member 13.

In the combustion space of the combustion section 12, the combustion gas is supplied to the combustion aid supply hole.
After being mixed with a combustion aid (for example, combustion air) given as indicated by an arrow B from 12a, the tip of the spark rod 30 according to the present invention, that is, between the spark rod body 31 and the inner peripheral surface of the combustion part 12, is mixed. It is ignited and burned by the generated spark discharge.

(Specific Example) In addition, an embodiment of the spark rod according to the present invention will be described with specific numerical values and the like in order to facilitate understanding of the configuration and the operation and effect.

Example 1 A metal pipe made of stainless steel (Japanese Industrial Standard SUS310) having an inner diameter of 2.8 mm and an outer diameter of 4 mm was cut into a length of 22 mm,
Grind the inner peripheral surface to a distance of 10 mm from one end to
A joint member was prepared by grinding the inner peripheral surface to 3.2 mm and a distance of 10 mm from the other end to form a female screw having a valley diameter of 3 mm and a pitch of 0.5 mm.

Outer diameter of 3 mm using silicon carbide composite material in a well-known manner
Thus, a spark rod body having a length of 200 mm and an electric resistance of 40Ω was prepared. The base end of the spark rod body is
After a sheet-shaped active silver braze having a width of 10 mm and a thickness of 0.05 mm was wound twice, it was inserted into one end of the joint member.
The spark rod body was housed in a carbon case with the base end inserted into the joint member, and maintained at 900 ° C. for 5 hours in a vacuum furnace under an atmosphere of about 10 ⁻⁵ mmHg. As a result, the spark rod main body was connected to the joint member to form a spark rod main body with a joint member. Incidentally, the composition of the active silver wax was 67 parts by weight of silver, 30 parts by weight of copper and 3 parts by weight of titanium.

The spark rod body with the joint member was formed into a spark rod by screwing and connecting the tip of a spark rod holder made of stainless steel in advance to the other end of the joint member.

The spark rod was used as an igniter for a radiant tube after being incorporated into a flame stabilizer. That is,
The spark rod was used continuously for three months while using natural gas as the combustion gas and air as the combustion aid and maintaining the temperature in the combustion furnace at 1200 ° C. The spark rod was stopped from supplying and supplying the combustion gas and the auxiliary agent, and was allowed to cool down to room temperature by natural cooling, and was then removed from the flame holder removed from the radiant tube.

When the connection state between the spark rod main body and the spark rod holder and the joint member was observed, no abnormality was found in the spark rod.

Example 2 A spark rod body was formed of a silicon nitride composite material, the electrical resistance of which was 0.5Ω, and the temperature in the combustion furnace was 110
Example 1 was repeated except that it was kept at 0 ° C.

At this time, no abnormality was observed in the connection state between the spark rod main body and the spark rod holder and the joint member.

Example 3 Example 1 was repeated, except that the composition of the active silver wax was 67 parts by weight of silver, 30 parts by weight of copper and 3 parts by weight of zirconium.

At this time, no abnormality was observed in the connection state between the spark rod main body and the spark rod holder and the joint member.

Examples 4-6 Examples 1-3 were repeated, respectively, except that the joint member was made of a heat resistant alloy instead of stainless steel.

At this time, no abnormality was observed in the connection state between the spark rod main body and the spark rod holder and the joint member.

(Modification) In the above description, the joint member 32 and the spark rod holder 33 are connected by screwing, but the present invention is not limited to this, and the connection is performed in another appropriate manner. Sometimes it is included.

(3) Effects of the Invention As is apparent from the above description, the spark rod according to the present invention is, as disclosed in the above [Means for Solving the Problems], a base end portion of a spark rod body formed of a conductive ceramic material. Is formed by detachably attaching a joint member made of a conductive metal, which is attached by insertion, to the tip of the spark rod holder by screwing. (I) It is generated with the combustion of the combustion gas. This has the effect of suppressing deterioration even when the heat amount increases and the temperature rises, and (ii) has the effect of prolonging the useful life.

Since the spark rod according to the present invention also has the above-described configuration, the electrical, thermal, and mechanical connections between the spark rod body made of a conductive ceramic material and the spark rod holder made of a metal conductive material are excellent. (Iv) Partial replacement is possible in the event of deterioration and material efficiency can be improved.

In addition, the spark rod according to the present invention has a structure in which the spark rod main body is supported by the holding portion and the spark rod holder is supported by the mounting member. This has the effect of suppressing vibration of the part and preventing damage.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a flame stabilizer according to the present invention. 10 flame stabilizer 11 cylindrical base 11A one end 11B other end 11a locking recess 11b cushioning member 11c, 11d adhesive layer 12 burning part 12a Combustion agent supply hole 13 ... Holder 13a ... Combustion gas supply hole 13b ... Holder hole 14 ... Insulating layer 20 ... Metal pipe 21 ... Metal pipe body 21A ... Open end 21B ... Base 21a ... Screw hole 22… Fixing screw 23… Combustion gas supply pipe 24… Mounting hole 30 … Spark rod 31… Spark rod body 32… Joint member 33… Spark rod holder 34… Insulating layer 35… Mounting member 36: Power supply terminal

──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kouichi Ichinoseki 30 Soya, Hadano-shi, Kanagawa Prefecture, Toshiba Ceramics Co., Ltd. (72) Inventor Haruo Murayama 30 Soya, Hadano-shi, Kanagawa Toshiba Ceramics Co., Ltd. (56) References JP-A-56-1481 (JP, A) JP-A-62-131257 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01T 13/00-13 / 56 F23Q 3/00 102

Claims (1)

(57) [Claims] 1. A radiant tube for generating a spark discharge, which protrudes into a combustion space of a flame stabilizer connected to an open end of a bottomed cylindrical metal pipe formed of a conductive ceramics material. The spark rod includes: (a) a spark rod body (31) formed of a conductive ceramic material, the tip of which protrudes into the combustion space of the flame stabilizer; and (b) a circle formed of the conductive ceramic material. A plurality of combustion gas supply holes (13a) are formed in a plate-shaped peripheral portion, and the combustion gas supply holes (13a) are connected to an inner peripheral surface of a substantially intermediate portion of the flame stabilizer. (3
A holding part (13) for holding 1) through an insulating layer (14), and (c) a joint made of a conductive metal, wherein a base end of the spark rod body (31) is attached by insertion. A member (32); and (d) a metal conductor, the tip of which is detachably attached to the joint member (32) by screwing, and the base end of which is at the center of the base of the metal pipe. A spark rod holder (33) attached by an attachment member (35) via an insulating layer (34) and having a base end connected to a power source.