JP3357517B2 - Method for producing mat for surface burning burner and mat for surface burning burner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mat for a surface burning burner and a method for producing the same, and more particularly to a mat for a surface burning burner in which fine metal wires are randomly and three-dimensionally entangled or woven in a mesh form and laminated. The present invention relates to the manufacturing method.

[0002]

2. Description of the Related Art Conventionally, a mat made of a porous ceramic material and a thickness of 20 mm formed of ceramic fiber have been used as a burner mat utilizing radiant heat generated by surface combustion.
There is a mat of up to 30 mm, or a mat made of thin metal wires, but a mat made of ceramic has a low strength and has the same speed between the gas upstream side and the downstream side during combustion, causing the gas to ignite upstream. Inconveniences such as a fire phenomenon easily occur.

On the other hand, a mat made of a thin metal wire has a high strength. If a thin metal wire having a wire diameter of 100 μm or less is used, the heat conduction in the direction of the mat surface becomes better than the heat conduction in the plate thickness direction. Due to the lower temperature on the back side of the combustion surface (upstream side of the gas), even a mat having a thickness of 2 to 3 mm does not flash back.

[0004]

However, for example, iron-chromium-aluminum is a metal composition having high resistance to high-temperature oxidation. It has been known that the high-temperature oxidation resistance is improved when a large amount of aluminum is contained in this composition, but when aluminum is contained in an amount of 5% by weight or more, the workability is deteriorated and the wire drawing cannot be performed. No high fine metal wire was obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its main object the object of the present invention is to prevent surface flash even when the plate thickness is small, and to provide surface combustion having good resistance to high-temperature oxidation. An object of the present invention is to provide a burner mat and a method for manufacturing the same at low cost.

[0006]

According to the present invention, there is provided a metal disk having a horizontal axis of rotation.
Continuous supply of molten raw metal from below, substantially circular
Grooves or flats that have a cross-section and that extend axially on the surface
A process of manufacturing a fine metal wire having a method and iron mat surface combustion burner characterized by having a step of laminating the thin metal wires randomly entangled or network form weaving or simply, chromium and Aluminum
The aluminum content is 10% by weight or more.
Made of heat-resistant metal with a substantially circular cross section
The surface has grooves or flat portions along the axial direction, and the wire diameter is 1
A metal thin wire having a thickness of not more than
Entangled, woven, or simply laminated
This is attained by providing a combustion burner mat characterized by the fact that: When the wire diameter is 100 μm or less,
Contains iron, chromium and aluminum which are hard to oxidize at high temperature,
The surface-burning burner mat obtained by randomly or three-dimensionally entangled or finely woven metal thin wires having an aluminum content of 10% by weight or more has a heat conduction in the direction of the mat surface in the thickness direction. The conductivity is better than that of the prior art. Even if the thickness is small, there is no flashback phenomenon, and the high-temperature oxidation resistance is improved. In particular, by forming a groove or flattened portion along the axial direction on the surface of the metal thin wires having a substantially circular cross-section, surface area of the metal thin wire becomes large, the heat dissipation effect, that is, backfire phenomenon preventing effect further improved.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a sectional view showing the structure of a surface combustion burner 1 to which the present invention is applied. This surface combustion burner 1 employs a combustion method in which a mixed gas of gas and air is passed through a porous mat, burned near the surface of the mat, and heat is transferred by radiation. In this combustion method, the temperature of the gas-air mixture downstream surface of the mat is about 900 ° C. or more.

The surface combustion burner 1 has a body 2 and a mat 4 in which a mixed gas supply path 3 of gas and air is formed at the rear. The mat 4 is formed by forming, for example, a cotton-like web with a heat-resistant metal thin wire having a wire diameter of 100 μm or less (small-diameter portion) as described later, laminating several tens of them, and compression-sintering them. Actually, a needle punching process for compression-molding a cotton web using a needle may be used. Also, it may be appropriately woven or randomly entangled.

Here, as shown in FIGS. 2A and 2B, the fine metal wire 5 used for the mat 4 has a wire diameter of 1 mm.
A V-shaped groove 5a or a flat portion 5b is formed along the axial direction in a part of a substantially circular cross section of not more than 00 μm. The thin metal wire 5 is made of a material composition having high resistance to high-temperature oxidation including iron-chromium-aluminum. For example, chromium is 24% by weight, aluminum is 10 to 25% by weight, and the remainder is iron. Here, when a rare earth element such as yttrium is included, the high-temperature oxidation resistance is further improved. Since toughness is lost when a large amount of aluminum is contained, toughness may be improved by adding titanium or the like.

FIGS. 3 (a) and 3 (b) are diagrams showing a configuration of a manufacturing apparatus of a thin metal wire 5 used for the mat 4 of the surface burning burner 1. FIG. This apparatus includes a copper disk 11 that rotates about a horizontally extending rotating shaft, and a cylindrical guide member that holds the raw metal M under the copper disk 11 so as to be exposed near the periphery of the copper disk 11. 12, a high-frequency heating coil 13 for locally heating the raw material metal M in the vicinity of the opening of the cylindrical guide member 12, and a cylindrical guide member 1
And a push-up member 14 that pushes up the tubular guide member 12 so as to gradually push up the raw material metal M in 2. The copper disk 11, the cylindrical guide member 12, the high-frequency heating coil 13 and the push-up member 14 are received in a chamber 16. The high-frequency heating coil 13 is connected to a high-frequency heating device 17 for exciting the coil, and the push-up member 14 is connected to an actuator 18 for driving the same.

The upper end of the high-frequency heating coil 13 and the copper disk 11 are preferably separated from each other by 10 mm or more in order to prevent the copper disk 11 from being affected by high-frequency heat. Further, the inner diameter of the cylindrical guide member 12 is set to φ10 mm or less in order to suppress the swing of the exposed portion of the raw material metal M,
The distance between the upper end of 2 and the copper disk 11 is preferably 5 mm or less. In addition, the resolution of the actuator 18 is 1/6 mm
/ S or more is preferable.

The operation of this embodiment will be described below. First, the raw metal M is held in the cylindrical guide member 12 and received in the chamber 16, and a vacuum (10 ⁻² to 10 ⁻³ Torr, for example, 10 ⁻⁴ Torr) is applied to prevent oxidation of the raw metal and the fine metal wires. After that, gas is introduced. Subsequent production is performed under an oxygen-free atmosphere, preferably under an inert gas atmosphere such as an argon gas. When the raw material metal M is thinned by performing the production in an inert gas atmosphere without maintaining the vacuum, the raw metal M is efficiently cooled.

Next, the copper disk 11 is rotated at a constant speed at a predetermined rotation speed. Then, while pushing up the cylindrical guide member 12, that is, the raw metal M in the form of a bar having a diameter of, for example, 10 mm or less by the push-up member 14, the distal end thereof is heated and melted by the high-frequency heating coil 13. Next, the thin metal wire 5 is formed by bringing the protruding tip end of the molten raw material metal M into contact with the peripheral edge forming the sharp edge of the rotating copper disk 11. As the leading end of the raw metal M decreases, the raw metal M is gradually pushed up by the push-up member 4 so that the copper disk 11
The actuator 18 is controlled such that the state of contact between the peripheral edge of the metal material M and the tip of the molten metal M is constant. Here, if the speed of pushing up the raw material metal M is too fast, the molten metal scatters when it comes into contact with the copper disk 11 and cannot be thinned. The pushing speed is determined by the relationship with the rotation speed of the copper disk 11. For example, when the rotation speed of the copper disk 11 is about 20 mm / sec, the pushing speed is 1 mm / sec.
sec or less, for example, about 0.5 mm / s is desirable. The wire diameter of the fine metal wire 5 can be set to 20 to 100 by changing the rotation speed of the copper disk 11, the rising speed of the raw metal M, and the like.
It can be changed to μm. Further, by changing the peripheral shape of the copper disk 11, as shown in FIGS. 3A and 3B, a V-shaped groove 5 extending along the axial direction is formed in a part of the fine metal wire.
a or the flat portion 5b can be formed. That is, if the peripheral shape of the copper disk 11 is formed into a sharp edge, a V-shaped groove is formed, and if the surface is formed to have a certain width, the flat portion 5b is formed.
Can be formed.

By forming a thin metal wire by the above-described method, an alloy containing 10% by weight or more of aluminum, which was conventionally difficult to reduce the wire diameter to 100 μm or less, can be easily thinned. This is because heat conduction in the direction of the mat surface is better than that in the plate thickness direction. That is, even if the plate thickness is small, there is no flashback phenomenon and the mat for surface burning burners with high resistance to high temperature oxidation is easily manufactured. Means possible.

FIG. 4 shows the increase in oxidized weight when the thin metal wire produced by the above-mentioned method is left in the air at 1100 ° C. for 100 hours. From this figure, 10% by weight of aluminum
It can be seen that anti-high Yutakasan resistance becomes extremely high by including more.

[0017]

As is apparent from the above description, according to the method for manufacturing a mat for a surface burning burner and the mat for a surface burning burner according to the present invention, aluminum is reduced by 10%.
High resistance, containing more than 10% by weight and adding a trace amount of rare earth elements
It has a substantially circular cross section from a material metal with good thermal oxidation properties, and
Wire diameter including flat part or V-shaped groove on the surface is 100μm or less
Metal wire can be easily obtained, and the mat can be used to form the mat , so that the heat conduction in the mat surface direction is better than the heat conduction in the plate thickness direction. Becomes Especially flat on the surface of metal wire with circular cross section
By including the portion or the V-shaped groove , the surface area is increased, the heat radiation effect is further improved, and the effect of preventing a flashback phenomenon is improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a structure of a surface combustion burner to which the present invention is applied.

2 (a) and 2 (b) are cross-sectional views of thin metal wires used in the mat for surface burning burner of FIG. 1.

FIG. 3A is a cross-sectional view showing a configuration of a manufacturing apparatus of a thin metal wire used for the mat of the surface combustion burner of FIG. 1;
(B) is the figure seen about BB line of (a).

FIG. 4 is a graph showing the relationship between the amount of aluminum added to a fine metal wire and the amount of increase in oxidized weight.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Surface combustion burner 2 Main body 3 Supply path of mixed gas 4 Mat 5 Fine metal wire 5a V-shaped groove 5b Flat part 11 Copper disc 12 Tubular guide member 13 High frequency heating coil 14 Push-up member 16 Chamber 17 High frequency heating device 18 Actuator

Continuation of the front page (56) References JP-A-53-116224 (JP, A) JP-A-5-180421 (JP, A) JP-A-3-225104 (JP, A) JP-A-3-94834 (JP) JP-A-1-159345 (JP, A) JP-A-51-3613 (JP, A) JP-A-5-172314 (JP, A) JP-A-9-47846 (JP, A) 9-29399 (JP, A) Japanese Utility Model Showa 51-3613 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F23D 14/12-14/16 B22D 11/06 330

Claims (6)

(57) [Claims] 1. The periphery of a metal disk having a horizontal rotation axis
Continuous supply of molten raw metal from below to the bottom
With a substantially circular cross-section and a groove along the surface in the axial direction.
A method for manufacturing a mat for a surface combustion burner, comprising: a step of manufacturing a thin metal wire having a flat portion; and a step of randomly entangled, woven in a mesh, or simply laminated the thin metal wire. 2. The method according to claim 1, wherein the molten raw metal is a metal circle.
The method for producing a mat for a surface combustion burner according to claim 1, wherein the process of producing the thin metal wire by supplying the metal wire to a lower portion of the peripheral edge of the board is performed in a non-oxidizing atmosphere. 3. The combustion burner according to claim 1, wherein the raw material metal includes iron, chromium, and aluminum, and the content of the aluminum is 10% by weight or more. Mat production method. 4. The method according to claim 3, wherein the raw material metal further contains a rare earth element. 5. A mat for a surface-burning burner, wherein metal wires are randomly entangled or woven in a mesh or simply laminated, wherein the metal wires include iron, chromium and aluminum;
The content of aluminum is 10% by weight or more.
Made of heat-resistant metal that has a substantially circular cross section and
Has a groove or flat portion along the axial direction, wire diameter 100μ
m . A mat for a combustion burner, comprising a metal wire having a diameter of not more than m . 6. The combustion burner mat according to claim 5 , wherein the fine metal wire further contains a rare earth element.