JPH0445728B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a burner nozzle for fuel injection used in a fuel injection section of a boiler, heating furnace, or the like.

BACKGROUND ART As is well known, burner nozzles for fuel injection are strongly required to have heat resistance and wear resistance.

Traditional fuel injection burner nozzles are typically
Made of heat-resistant metal such as SUS310.

Problems to be Solved by the Invention However, the nozzle tip of a fuel injection burner used in a fuel injection part of a boiler, heating furnace, etc. that operates continuously for a long period of time may be damaged for a short period of time due to the passage of foreign matter contained in the fuel. During this process, the orifice portion in particular suffers erosion and deformation, and the hole diameter changes due to wear of the orifice.

This invention was made to solve the above problems, and provides a long-life fuel that does not melt or deform the orifice even when used in the fuel injection part of boilers and heating furnaces that are operated continuously for long periods of time. The purpose is to provide a burner nozzle for injection.

Means for Solving the Problems Therefore, in order to achieve this object, the gist of the present invention is to provide a burner nozzle for fuel injection that is attached to a fuel injection part of a boiler, a heating furnace, etc. An orifice member formed of oxide ceramics, and a heat-resistant metal outer peripheral member having a recessed portion having the same diameter as the orifice member at its tip, the orifice member being fitted into the recess, and the outer peripheral member being A nozzle for a burner for fuel injection, characterized in that the orifice member is fixed to the outer peripheral structure by caulking.

Effect The burner nozzle for fuel injection used in the fuel injection part of a boiler, heating furnace, etc. according to the present invention does not cause melting or deformation of the orifice even if the boiler or heating furnace is operated for a long time. Since it is fitted and fixed by caulking, it is not only sturdy, but also
Orifice members can be easily replaced.

By forming a recess with the same diameter as the orifice member at the tip of the outer circumferential member, fitting the orifice member into the recess, and caulking the outer member, the orifice member is fixed to the outer member. The orifice member can be easily attached and detached, and the orifice member can be firmly fixed during use.

Embodiments Hereinafter, the present invention will be explained with reference to illustrated embodiments.

FIG. 1 is a sectional view in the jetting direction showing a first embodiment of a burner nozzle for fuel injection according to the present invention, and FIG. 2 is a plan view thereof.

This nozzle has an orifice member 2 made of non-oxide ceramic fitted to the tip of an outer peripheral structure 1 made of heat-resistant metal such as SUS310.

The outer peripheral structure 1 has a tapered high-temperature fluid flow path 3 whose inner diameter becomes smaller as it approaches the orifice member 2, and the minimum diameter of the high-temperature fluid flow path 3 and the inner diameter of the orifice 4 of the orifice member 2 are are in agreement.

The nozzle is attached to a fuel injection section of a boiler, heating furnace, etc., and injects fuel through it.

The orifice member 2 is approximately ring-shaped and is made of non-oxide ceramic, which has extremely superior heat resistance and wear resistance compared to heat-resistant steel.

Examples of non-oxide ceramics include silicon nitride and silicon carbide.

The orifice member 2 is fitted into a recess 5 formed at the tip of the outer peripheral structure 1, and
It is fixed to the entire outer periphery structure 1 so that it will not come off by means of fixing pieces 6 (in the embodiment, there are four places equally spaced around the circumference) formed by caulking several locations on the outer periphery. In this way, the orifice 4 and the high temperature fluid flow path 3 are connected.

The inner diameter of the recess 5 is equal to the outer diameter of the orifice member 2.

If a nozzle with such a structure is attached to the fuel injection part of a boiler or heating furnace, and the boiler or heating furnace is operated continuously for a long time, the orifice 4 will be damaged because the orifice 4 is made of non-oxide ceramics. There is no risk of melting, deforming, or expanding the inner diameter of the orifice.

When replacing the orifice member 2,
Since it is attached simply by caulking, it is easy to replace.

Note that if a sufficient caulking allowance is provided for the fixing piece 6, there is no fear that the orifice member 22 will fall off even if the temperature rises.

Furthermore, since the orifice member 2 is attached by caulking, cracking of the orifice member 4 due to thermal expansion can be suppressed.

Other Embodiments Next, second to fourth embodiments of the fuel injection burner nozzle according to the present invention will be described with reference to FIGS. 3 to 5.

In the second embodiment, as shown in FIG.
is formed. Similar to the first embodiment, a ring-shaped orifice member 12 made of non-oxide ceramic
is fitted into this recess 15 and fixed by a plurality of fixing pieces 16 formed around the recess 15 by caulking at equal circumferences.

The inner diameter of the orifice 14 of the orifice member 12 is set smaller than the uniform inner diameter of the high temperature fluid path 13 of the outer peripheral structure 11.

In the third embodiment, as shown in FIG. 4, a non-oxide ceramic orifice member 22 is fitted into a recess 25 formed at the tip of a cylindrical heat-resistant metal outer peripheral structure 21. The orifice member 22 is fixed by a plurality of fixing pieces 26 formed by caulking at equal circumferences.

In this third embodiment, the high temperature fluid flow path 23 of the outer circumferential structure 21 consists of a uniform inner diameter section 23a and a tapered inner diameter section 23b. The orifice 24 of the orifice member 22 has a tapered portion 24b continuous with the tapered inner diameter portion 23b and a reverse tapered portion 24b.

Furthermore, in the fourth embodiment, as shown in FIG.
An orifice member 32 made of non-oxide ceramic and having a substantially arcuate cross-section is fitted into a recess 35 of the outer peripheral structure 31 made of heat-resistant metal. This orifice member 3
2 is fixed by a plurality of fixing flats 36 formed by caulking at equal circumferences.

In this fourth embodiment, the high temperature fluid flow path 33 of the outer peripheral structure 31 has a uniform inner diameter, and the orifice member 3
A plurality of orifices 34 are provided radially.

Incidentally, it goes without saying that the nozzle of the burner for fuel injection according to the present invention is not limited to the above-described embodiment, and various modifications can be made depending on the application.

Effects of the Invention As is clear from the above explanation, the orifice member is made of non-oxide ceramics with extremely excellent heat resistance and wear resistance, and a concave portion with the same diameter as the orifice member is formed at the tip of the outer peripheral structure. Then, a part of the outer peripheral structure made of heat-resistant metal is caulked and the orifice member is fitted into the recess and fixed, so that when performing the caulking work, the orifice member can be fixed evenly and reliably in the optimum position. Moreover, even when used in fuel injection parts of boilers and heating furnaces that operate continuously for long periods of time, the orifice will not melt or deform, and not only can the life of the nozzle be extended, but the orifice can be removed simply by caulking. Since the member is fixed to the outer peripheral structure, cracking due to thermal expansion of the orifice member can be suppressed.
Moreover, an excellent effect is obtained in that the orifice member can be easily replaced.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view in the jetting direction showing a first embodiment of a burner nozzle for fuel injection according to the present invention;
The figure is the same plan view, and Figures 3 to 5 are the second to fourth burner nozzles for fuel injection according to the present invention.
FIG. 3 is a cross-sectional view in the injection direction showing an example of the invention. 1, 11, 21, 31... outer peripheral structure, 2, 1
2, 22, 32...orifice member, 4, 14,
24, 34... Orifice, 6, 16, 26, 3
6...Fixed piece.

Claims (1)

[Claims] 1. In a burner nozzle for fuel injection that is attached to a fuel injection part of a boiler or heating furnace, an orifice member made of non-oxide ceramics and a recessed part of the same diameter as the orifice member formed at the tip are made of heat-resistant metal. A nozzle for a burner for fuel injection, characterized in that the orifice member is fitted into the recess, and the orifice member is fixed to the outer circumferential structure by caulking the outer circumferential structure.