JP3096363B2 - Gas flame burner for high load combustion with straight flame - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a straight flame type high load combustion gas burner which can be suitably used in an industrial furnace such as a forging furnace.

[0002]

2. Description of the Related Art For example, a furnace body of a forging furnace has a rectangular or similar cross-sectional shape, and a gas burner mounted on the furnace body forms a straight flame substantially coaxial with a burner axis to provide high load. It is configured to burn. Forging furnaces equipped with such a gas burner require energy-saving, although the size of the furnace body needs to be large enough to prevent the flame from directly contacting the furnace wall and the object to be heated. In order to realize space saving and space saving,
There is a need for a gas burner that burns completely at high load in a narrow combustion chamber.

In order to solve such a problem, conventionally, as shown in FIG. 9, a gas main flame hole 4 is formed at an end 3 of a gas supply pipe 1 to which gaseous fuel is supplied. 3
Is provided with a burner top 6 having a hollow truncated cone shape having a plurality of through-holes 5, and a mixing chamber for mixing combustion air supplied into a combustion tube 7 and gas fuel ejected from the gas main flame holes 4. It is configured to mix and burn within 8.

In such prior art, since the gaseous fuel is discharged from the center of the burner, it is necessary to gradually mix the fuel gas and the combustion air in a stepwise manner. The volume of the mixing chamber 8 must be increased by increasing the axial length of the burner top 6 and increasing the inner diameter of the large-diameter end 9 of the burner top 6. However, there is a problem that the flame length becomes longer.

In another prior art, a swirling flame type gas burner for swirling and supplying combustion air is known, but a swirling chamber and swirling vanes are separately required to swirl the combustion air. Therefore, there is a problem that the size of the gas burner increases and the manufacturing cost increases.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a straight flame type high load combustion gas burner capable of complete combustion under a high load by shortening the flame length with a simple structure. That is.

[0007]

According to the present invention, there is provided a cylindrical combustion cylinder to which combustion air is supplied from a rear end portion to a front end portion, wherein the combustion air is provided between the combustion cylinder and an inner peripheral surface thereof. A burner top is formed by forming an annular air flow path passing therethrough, and the burner top has a hollow truncated cone-shaped cone portion having a larger diameter as approaching the front end portion, and a small-diameter end portion of the cone portion. A straight flame type high load combustion gas burner in which a straight cylindrical portion having a connection hole to which a gas supply pipe for guiding gaseous fuel is connected is formed. A gas main flame hole communicating the enclosed mixing chamber and the connection hole on a central axis, and extending radially from an outer peripheral portion of the gas main flame hole to a large-diameter end portion of the cone portion; A plurality of gas guide passages communicating with the end face of the portion, and each gas guide passage A plurality of gas flame holding holes that open toward the inner peripheral surface at an intermediate position, and a plurality of through holes that communicate the cone portion in the thickness direction between the gas guide passages are formed. It is a flame type high load combustion gas burner.

Further, the present invention is characterized in that the cone portion is integrally formed with an annular flange projecting radially outward from a large diameter end thereof.

Further, the present invention is characterized in that the flange is provided with ignition means.

[0010]

According to the present invention, the gas fuel supplied from the gas supply pipe to the cylindrical portion of the burner top is discharged from the gas main flame hole and guided to a plurality of radially formed gas guide passages. The gas fuel in each gas guide passage is discharged from the large-diameter end of the cone portion, and is discharged into the mixing chamber from the middle position of the gas guide passage via the gas flame holding hole.
In this way, the gas fuel supplied from the gas supply pipe is dispersed and released from a plurality of locations other than the gas main flame holes,
Mixing of the gaseous fuel and combustion air is promoted, and complete combustion can be performed at a high load without increasing the size of the mixing chamber.

Further, in the present invention, since a flange is formed on the cone portion so as to protrude outward in the radial direction, a negative pressure portion is generated by the combustion air abutting on the flange, thereby forming the gas fuel and the combustion gas. Mixing with air is promoted to enhance flame holding.

Further, in the present invention, since the ignition means is provided on the flange, the gas fuel discharged from the large-diameter end portion through the gas guide passage can be ignited reliably, and the ignition is ensured. Can be achieved.

[0013]

1 is a sectional view showing a gas burner 13 according to one embodiment of the present invention, and FIG. 2 is a front view of a burner top 14 shown in FIG. 1 as viewed from the left. The gas burner 13 according to the present embodiment has a straight cylindrical combustion tube 17 to which combustion air is supplied from a rear end portion 15 toward a front end portion 16 by a blower or the like. The burner top 14 is arranged by forming an annular air flow path 19 through which combustion air passes.

The burner top 14 is connected to a hollow frustoconical cone 20 having a larger diameter as it approaches the front end 16 along the axial direction, and a small diameter end 21 of the cone 20 to connect with the city gas or the like. Gas supply pipe 23 for leading gas fuel
Is formed with a cylindrical portion 25 having a connection hole 24 to which is connected.

A partition wall 2 is provided between the mixing chamber 27 surrounded by the inner peripheral surface 26 of the cone portion 20 and the connection hole 24.
A gas main flame hole 29 is formed in the partition wall 28 to communicate the mixing chamber 27 and the connection hole 24 on the center axis. The inner peripheral surface 26 of the cone portion 20 has an angle θ1, and the angle θ1 is selected to be, for example, 30 to 50 °.

The cone 20 has the gas main flame hole 2
A plurality of gas guide passages 31 are formed extending radially from the partition wall 28, which is the outer periphery of 9, to the large-diameter end portion 30. Each gas guide passage 31 opens at an end face 33 facing the front end 16 of the large diameter end 30, and discharges a part of the gas fuel supplied from the gas supply pipe 23 forward from the large diameter end 30. I do. Further, a plurality of gas flame holding holes 34 that open toward the inner peripheral surface 26 are formed at intermediate positions of the gas guide passages 31. Therefore, a part of the gas fuel flowing into the gas guide passage 31 is also supplied from the gas flame holding hole 34 to the mixing chamber 27.
It is released toward.

A plurality of through-holes 35 are formed in the cone portion 20 and communicate with each other in the thickness direction between the gas guide passages 31 adjacent in the circumferential direction. Each through-hole 35 has an angle θ2 inclined toward the large-diameter end 30 as it approaches the inner peripheral surface 26 with respect to the inner peripheral surface 26, and extends from the rear end 15 to the front end 16 of the combustion cylinder 17. The supplied combustion air can be smoothly guided into the mixing chamber 27 to generate a vortex, thereby facilitating mixing with the gaseous fuel.

The burner top 14 also has an annular flange 36 formed at the large-diameter end 30 so as to protrude outward in the radial direction and to be integrally connected. With the flange 36, a negative pressure portion is formed on an end face 38 connected to the end face 33 by combustion air flowing through the air flow path 19 as indicated by an arrow 37,
This promotes the mixing of the gaseous fuel and the combustion air, and enhances the flame holding. The flange 3
6 is connected to the vicinity of the tip of a spark rod 39 serving as an ignition means, and discharges between an electrode 40 protruding from the end face 38 and the flange 36 to generate an electric spark, which is discharged from the gas guide passage 31. The fuel gas can be ignited.

The gas burner 13 having the above configuration
As a result, as shown in FIG. 3, the flame length L can be shortened and high load combustion can be performed.

FIG. 4 shows a forging furnace 4 having a gas burner 13.
FIG. In the forging furnace 41 requiring a large amount of heat in the narrow combustion chamber 43, the flame length L = 7 at a high load of 10,000 kcal / hr by the gas burner 13 of this embodiment.
A short flame of 00 mm is formed, and the object to be heated 44, which is a mechanical part, can be efficiently heated by using the radiant heat of the flame 45.

In the above-described embodiment, a straight cylindrical combustion cylinder 17 is used.
However, as another embodiment of the present invention, as shown in FIG. 5, a gas burner 13a having a combustion cylinder 46 whose front end 16 is tapered may be used. Such a gas burner 13a has a calorific value of 1.
It is used as a radiant tube burner 47 with a hole as shown in FIG. 6 which requires a flame length L of 500,000 kcal / hr, a flame length L = 500 mm, and a flame speed of about 80 m / sec.

Further, as another embodiment of the present invention, when it is desired to further shorten the flame length L, as shown in FIG. 7, a gas burner 13b having a combustion cylinder 48 whose front end 16 has a small diameter is used. Such a gas burner 13b is
As shown in FIG. 8, a carriage 50 on which a plurality of objects to be heated 49 are placed is housed in a furnace body 51 and has a calorific value of 100,000 kca.
1 / hr flame length L = 400mm, flame velocity 120m
/ Sec is used for the bogie furnace 51 which requires a relatively short flame length L and a uniform temperature distribution.

In this way, by simply reducing the diameter of the front end portion 16 of the combustion cylinder 48 in accordance with the required flame length L, complete combustion can be realized with a high load.

[0024]

As described above, according to the present invention, the gas guide passage and the gas flame holding hole are formed in the burner top, and the gas fuel is discharged from a plurality of locations other than the gas main flame hole. Thus, the mixing with the combustion air is promoted, and the combustion with a high load and a short flame length can be realized. Moreover, since the flame length can be shortened by processing only the burner top, the present invention can be implemented with a simple configuration and at low cost.

Further, since the flange is formed integrally with the large diameter portion of the burner top, the mixing is promoted and the flame holding can be strengthened.

Further, since the ignition means is provided on the flange, it is possible to reliably ignite the gas fuel discharged through the gas guide passage.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a gas burner 13 according to one embodiment of the present invention.

FIG. 2 is a front view of the burner top 14 as viewed from the left in FIG.

FIG. 3 is a simplified diagram showing a flame formed by a gas burner 13;

FIG. 4 is a simplified sectional view of a forging furnace 41 provided with a gas burner 13;

FIG. 5 is a simplified sectional view showing a gas burner 13 according to another embodiment of the present invention.

6 is a simplified cross-sectional view of a radiant tube burner 47 including the gas burner 13a shown in FIG.

FIG. 7 shows a gas burner 13b according to still another embodiment of the present invention.
FIG.

8 is a simplified sectional view showing a bogie furnace 53 including the gas burner 13b shown in FIG.

FIG. 9 is a cross-sectional view of a typical prior art.

[Explanation of symbols]

 13, 13a, 13b Gas burner 14 Burner top 15 Rear end 16 Front end 17, 46, 48 Combustion cylinder 18 Inner peripheral surface 19 Air flow path 20 Cone section 21 Small diameter end 23 Gas supply pipe 24 Connection hole 25 Tube part 27 Mixing Chamber 29 Gas main flame hole 30 Large diameter end 31 Gas guide passage 34 Gas flame holding hole 35 Through hole 36 Flange 39 Spark rod 40 Electrode

Claims (3)

(57) [Claims] An annular air flow path through which the combustion air passes is provided in a cylindrical combustion cylinder to which combustion air is supplied from a rear end portion to a front end portion. A burner top is formed and disposed on the burner top. A cone portion having a hollow truncated cone shape having a larger diameter as approaching the front end portion, and a gas supply leading to the gas fuel, being connected to a small diameter end portion of the cone portion In a straight flame type high load combustion gas burner in which a straight cylindrical tubular portion having a connection hole to which a pipe is connected is formed, the cone portion is connected to a mixing chamber surrounded by an inner peripheral surface thereof. A gas main flame hole communicating with the hole on the central axis, a plurality of gas radially extending from the outer peripheral portion of the gas main flame hole to the large diameter end of the cone portion, and communicating the connection hole with the end surface of the large diameter end. Of the gas guide passages and the inner peripheral surface at an intermediate position of each gas guide passage. A plurality of gas flame holding holes Nde opening,
A straight flame type high load combustion gas burner, wherein a plurality of through holes are formed between the respective gas guide passages to communicate the cone portion in the thickness direction thereof. 2. The straight flame type high load combustion according to claim 1, wherein an annular flange projecting radially outward from a large-diameter end of the cone portion is integrally formed with the cone portion. For gas burner. 3. The straight burn type high load combustion gas burner according to claim 2, wherein ignition means is provided on said flange.