JPS6215235Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a rapid heating furnace for heated steel wire.

Conventional steel wire heating materials are known to heat the wire from both sides of the furnace wall using high-speed jet burners 18, as shown in Fig. 4. Since the secondary radiation heat is used, the time required to heat the wire is 12 times per 1 mm of wire. It took ~15 seconds.

This idea improves the above-mentioned furnace by increasing the rate of convective heat transfer of the heating gas and heating the wire by 3 times.
The main objective is to shorten the time to ~5 seconds, and other objectives are to reduce the size of the furnace body, increase thermal efficiency, and reduce fuel consumption.

The present invention will be explained with reference to the embodiments shown in the accompanying drawings.A furnace body 1 is made of a refractory heat insulating material and is divided into a preheating zone 2 and a heating zone 3.

The wire rod 5 is continuously inserted into the heating chamber 4 from the wire inlet, and the wire rod 5 is heated by the exhaust gas used in the heating zone 3.
Preheat. The preheating effect of the wire 5 passing through the preheating chamber 4 is enhanced due to the nearly perpendicular contact with the gas by the resistor 6.

Next, the wire 5 is sent to the heating chamber 7 of the heating zone 3.
A bar 8 made of a special refractory is provided in the heating chamber 7 to hold the wire 5 at an intermediate position between the upper and lower sides of the furnace. Further, in the heating chamber 7, a number of high-speed jet burners 9 are installed opposite to the furnace wall perpendicular to the direction in which the wire travels. The high-speed gas ejected from the high-speed jet burner 9 is injected oppositely above and at right angles to the wire 5, and a curved surface 10 is formed on the furnace wall opposite the burner 9, so that the high-speed gas flow rotates in an elliptical shape. The effect of heat transfer to the wire rod 5 is enhanced.

The opposing burners 9 are arranged in a zigzag manner with respect to the traveling direction of the wire 5, and the interval C between adjacent burners 9 is as small as possible, and the opposing burners 9 are provided with an interval D in the vertical direction to improve convective heat transfer of the gas. urge

Arrow A7 indicates the gas flow direction, and 11 indicates the exit of the wire.

As shown in FIG. 3, the burner 9 has an air mixed gas pipe 12 connected to a high-speed nozzle 13, and the high-speed nozzle 13, a fire chamber 15 with a spark plug 14 attached thereto, and a combustion chamber 16 are arranged in series. A plurality of high speed jet nozzles 17 are provided in parallel at the end of the jet nozzle.

High-pressure mixed gas is passed through the high-speed nozzle 13 to the ignition chamber 15
The combustion gas is injected into the combustion chamber 16 and combusted in the combustion chamber 16, and the gas is further expanded to a high temperature and pressure, and the combustion gas is injected onto the wire 5 from a plurality of jet nozzles.

In the present invention, the wire is preheated in the preheating chamber 4, so exhaust heat can be used.

As described above, high-speed gas is injected upward and downward from the perpendicular direction to the wire 5, and the high-speed gas flow is rotated in an elliptical shape, so that the wire is mainly heated by convective heat transfer of the high-speed gas.

Also, in order to increase the convection speed inside the furnace, the cross-sectional area inside the furnace is made as small as possible.

Therefore, the gas velocity in the furnace can be averaged and the temperature can be made uniform.

Therefore, compared to the conventional wire heating furnace, the rapid wire rod of the present invention takes 12 to 15 seconds to heat from 20°C to 950°C per mm of wire in the conventional furnace, but it takes 3 to 5 seconds in the present invention. In addition, the efficiency of conventional furnaces is 45~
50%, but in the present invention it is 50 to 60%, and if the outer mold of the conventional furnace is 100, it is 30 in the present invention.

No inferiority was observed in the heated product.

Therefore, by installing the wire rapid heating furnace of the present invention, equipment costs and installation area can be saved, and the heat source is also economical.

[Brief explanation of the drawing]

FIG. 1 is a sectional front view of the present invention, FIG. 2 is a sectional view taken along the line -- in FIG. 1, FIG. 3 is a vertical sectional front view of a high speed jet burner, and FIG. 4 is a cross sectional view of a conventional furnace. 4... Preheating chamber, 5... Wire rod, 6... Resistor, 7
... Heating chamber, 8 ... Bar, 9 ... High speed jet burner, 10 ... Curved surface.

Claims (1)

[Scope of utility model registration request] In the heating chamber 7, a large number of high-speed jet burners 9 are provided in a zigzag pattern facing each other on both furnace walls in a direction perpendicular to the direction in which the wire advances. High-speed jet burner 9 for jetting on both sides
This rapid steel wire heating furnace is constructed by shifting the position of the steel wire rod and forming a curved surface 10 on the furnace wall against which high-velocity high-temperature gas collides.