JPH0435692Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a burner that ejects fuel and combustion-supporting gas from a nozzle at its tip for combustion.

[Conventional technology]

Burners or injection lances used in electric furnaces for refining metals and firing furnaces for firing ceramics are exposed to high-temperature atmospheres, so they are equipped with a cooling jacket around the burner for cooling. There is.

FIGS. 2 and 3 show conventional burners of this type. Both burners 1 and 2 have a fuel flow path 3 formed in the center, and a combustion-supporting gas flow path 4 on the outer periphery of the fuel flow path 3. Furthermore, there is a cooling jacket 5 on the outer circumferential side.
is formed.

First, the nozzle 6 of the burner 1 shown in FIG. The ends are also fixed by welding. The nozzle 8 of the burner 2 shown in FIG. 3 is removably screwed onto the tip of an inner cylinder 9, and the cooling jacket 5 extends to the outer periphery of the tip of the nozzle 8. This cooling jacket 5
The base end portion of is fixed by a cap nut or welding, and is integrally formed. In the figure, F indicates fuel, G indicates combustion supporting gas, and W indicates cooling water.

[Problem that the invention attempts to solve]

However, in the one shown in FIG. 2, the nozzle is fixed by welding, so it is difficult to replace the nozzle, and in the one shown in FIG.
Since the cooling jacket was provided up to the tip of the burner, the tip of the cooling jacket was exposed to high temperatures and was severely damaged.

Furthermore, in both cases, the proximal end of the cooling jacket is fixed to the inner cylinder, so due to the thermal expansion of the cooling jacket exposed to high temperatures, stress is applied to the cooling jacket in the compressive direction, and stress in the inner cylinder is applied in the tensile direction. In addition, there was a risk of damage to each member and welding location.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a burner in which damage to the cooling jacket can be reduced and the nozzle can be easily replaced.

[Means for solving problems]

In order to achieve the above object, the present invention provides a nozzle that ejects fuel and combustion-supporting gas from its tip for combustion, an inner cylinder that forms a flow path for the fuel and combustion-supporting gas, and an outer periphery of the inner cylinder. In the burner equipped with a cooling jacket provided at At the same time, an elastic member is provided at the base end of the inner cylinder to press the cooling jacket toward the tip of the burner, and the cooling jacket is sandwiched between the elastic member and the enlarged diameter stepped portion of the nozzle. It is characterized by

[Effect]

Therefore, since the front end of the cooling jacket is covered by the enlarged-diameter stepped portion of the nozzle, it is not exposed to high temperatures and is less likely to be damaged, and the nozzle can be easily attached and detached. Furthermore, since the cooling jacket is pressed by the elastic member, stress due to thermal expansion of the cooling jacket can be absorbed by the elastic member.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

The burner 11 of the present invention has a fuel flow path 3 in the center, a combustion-supporting gas flow path 4 on the outer periphery, and a cooling jacket 5 on the outer periphery, as in the conventional example, and a nozzle 12 at the tip. is installed.

The fuel flow path 3 is formed of an inner cylinder 14 having a female threaded portion 13 at its tip, and the combustion-supporting gas flow path 4 is formed between the outer peripheral surface of the inner cylinder 14 and the cooling jacket 5.
is formed between the inner circumferential surface of the Furthermore, the cooling jacket 5 is formed as a flow path that reverses at the front end portion 18 by an inner peripheral wall 15, a partition wall 16, and an outer peripheral wall 17, which also serves as a burner outer cylinder and forms the combustion-supporting gas flow path 4 on its inner periphery. A closing member 19 for closing the end of the combustion-supporting gas flow path 4 is attached to the base end of the inner peripheral wall 15. The closing member 19 is slidably and airtightly fitted onto the outer peripheral surface of the inner cylinder 14 via an O-ring 20, and has one end attached to a receiving member 21 formed on the outer periphery of the proximal end of the inner cylinder 14. is pressed toward the tip of the burner 11 by the coil spring 22, which is a resilient member that is in contact with the coil spring 22.

On the other hand, the nozzle 12 attached to the tip of the burner 11 has a female threaded portion 13 of the inner cylinder 14 at the base end.
A male threaded portion 23 is formed to be screwed into the cooling jacket 5, and an enlarged diameter stepped portion 24 that covers the front end portion 18 of the cooling jacket 5 is formed on the outer circumferential surface. Further, inside the nozzle 12, there are formed a fuel jet port 25 and combustion supporting gas jet ports 26, 26, which are similar to the conventional ones and communicate with the fuel flow path 3 and the combustion supporting gas flow path 4, respectively.

By forming the burner in this way, the front end of the cooling jacket is not covered by the enlarged diameter step of the nozzle and is exposed to high temperatures, which prevents damage to the front end and makes it easy to attach and detach the nozzle at the tip. This makes it easy to replace the nozzle. Furthermore, since the cooling jacket is pressed toward the tip of the burner by an elastic member and is crimped and held against the enlarged diameter step of the nozzle, even if the cooling jacket is heated and thermally expands during use, this elastic Since it can be absorbed by the members, excessive force is not applied to each member, and damage to welded parts etc. can be prevented.

Furthermore, since the front end of the burner and the enlarged-diameter stepped portion of the nozzle can always be kept in good contact, heat conduction can be maintained in the best condition.

Incidentally, a burner formed in such a way that a separately formed cooling jacket is fitted onto the burner main body having a fuel flow path and a combustion-supporting gas flow path can also be constructed in the same manner. The shape of the lance (including the lance) is formed into an optimal shape depending on the temperature conditions during use, the type of fuel, etc., and is not limited to the above embodiment.

[Effect of idea]

As explained above, the present invention has a nozzle that is removably attached with an enlarged diameter step formed on the outer circumferential surface, and a resilient member disposed at the base end of the inner cylinder and the enlarged diameter step. Since the cooling jacket is clamped, the front end of the cooling jacket is covered by the enlarged diameter step of the nozzle.
Since the cooling jacket is not exposed to high temperatures, damage to the cooling jacket can be prevented, and since the nozzle can be easily attached and detached, the nozzle can be easily replaced when damaged.

Furthermore, since the cooling jacket is pressed by the elastic member and held between it and the enlarged diameter step of the nozzle, the elastic member can absorb the stress caused by the thermal expansion of the cooling jacket, thereby preventing the inner cylinder from being forced. No force is applied and damage to welded parts etc. can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a burner showing an embodiment of the present invention, and FIGS. 2 and 3 are cross-sectional views of a burner showing conventional examples. 3... Fuel flow path, 4... Combustion supporting gas flow path, 5...
Cooling jacket, 11... Burner, 12... Nozzle, 13... Female threaded portion, 14... Inner cylinder, 18...
...Front end portion, 19...Closing member, 22...Coil spring, 23...Male thread portion, 24...Expanded diameter stepped portion.

Claims (1)

[Scope of utility model registration request] A burner comprising a nozzle that ejects fuel and combustion-supporting gas from its tip for combustion, an inner cylinder that forms a flow path for the fuel and combustion-supporting gas, and a cooling jacket provided on the outer periphery of the inner cylinder, An enlarged diameter stepped portion is formed on the outer peripheral surface of the nozzle to cover the front end of the cooling jacket, and the proximal end of the nozzle is detachably attached to the distal end of the inner cylinder, and the cooling jacket is attached to the proximal end of the inner cylinder. A burner characterized in that a resilient member is provided for pressing the jacket toward the tip of the burner, and a cooling jacket is held between the resilient member and the enlarged diameter step portion of the nozzle.