JPS6321568Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a bell-shaped annealing furnace used for annealing cold-rolled steel materials.

Conventionally, in this type of bell-shaped annealing furnace, as shown in Fig. 4, materials to be annealed such as tight coils and oven coils are piled up on the base, and then an inner cover b is placed on the base and the burner of the heating cover c is placed on top of the base. Protective gas (atmosphere gas) is isolated from the combustion chamber and the atmosphere.
The material to be annealed is blown in to prevent the oxidation of the material to be annealed by air, and the inner cover b is heated by combustion in the burner d installed in the heating cover c, and the heat is transferred from the inner cover b to the protective gas, and the material to be annealed is heated. There is one that heats material a. Incidentally, several burners d are provided on the heating cover c, g, h, i, j, m,
n is the center line of each burner d.

However, in this furnace, the flame e of the burner d hits the lining f inside the heating cover, locally raising the temperature of that part, causing an increase in the temperature of not only the local part of the heating cover but also the entire heating cover. Heat loss is large because a lot of heat is dissipated to the outside.

In addition, the heating cover also has a short lifespan, and the inner surface of the heating cover is located at the lining f, where the flame e of the burner d directly hits.
As they wear out and fall off, maintenance and inspections must be performed frequently. Moreover, the inside surface of the heating cover is a poor working environment.
This work requires a lot of time.

In view of the above, the present invention aims to extend the life of the heating cover and to save energy.

Another objective is to reduce maintenance costs and time.

The present invention provides a bell-shaped annealing furnace in which a heating cover is placed on an inner cover with a gap therebetween and a burner is provided on the heating cover, and a burner flame rectifying plate is provided in the gap to obliquely intersect with the center line of the burner. The bell-shaped annealing furnace is characterized in that the distance between the rectifier plate and the inner cover is narrower toward the downstream.

Embodiments of the present invention will be described below with reference to the accompanying drawings. An inner cover 1 having a ring shape in cross section is covered with a heating cover 2 having a substantially ring shape in cross section with a gap W therebetween.

A plurality of burners 3 are provided through the heating cover 2 at equal pitches, and a lining L is provided on the inner surface thereof.

Center lines 3a, 3b, 3c, 3d of each burner 3,
3e and 3f are arranged so as to be concentric with the inner cover 1 and tangent to a circle 4 passing through the midpoint of the gap W.

A burner flame rectifying plate 5 is provided in the gap W to obliquely intersect with the center line of the burner 3.

This burner flame rectifier plate 5 is fixed to the inner cover 1 via support pieces 6a and 6b, but since the support piece 6a is longer than the support piece 6b, the distance D between the inner cover 1 and the rectifier plate 5 is It gets narrower as you go downstream.

The burner flame rectifying plate 5 is made of a material that can withstand high temperatures, such as fine ceramic or heat-resistant steel, and is attached by a welded bolt joint, a rivet joint, or the like.

To explain the operation of this embodiment, the flame (high-temperature gas) of the burner 3 moves at a speed of itself (for example, several meters/
sec to several tens of m/sec), and when this flame is injected in the direction of arrow A3, it hits the burner flame rectifier plate located on the center line of the burner and is guided by this rectifier plate 5, causing the inner cover 1 to flow. The inner cover 1 is bent and flows in the direction of the arrow A1, heating the inner cover 1.

At this time, the heat that conventionally was transferred to the heating cover 2 through heat transfer when the burner flame directly hits the inner surface of the heating cover gives a large amount of heat to the rectifying plate 5, making the rectifying plate 5 reach a high temperature, and radiating heat. Heat is transferred to the inner cover 1 and the heating cover 2. The high-temperature gas, which still retains a considerable amount of heat even after once hitting the current plate 5, flows at high speed on the outer circumferential surface of the inner cover 1 and closes the inner cover 1.
give more heat to As a result, more of the heat of the high-temperature gas that conventionally transferred to the heating cover 2 is transferred to the inner cover 1, so that the material M to be annealed, such as a tight coil or an oven coil, in the inner cover can be annealed more quickly and uniformly. heated to.

Moreover, the overall temperature of the heating cover 2 decreases, and the amount of heat dissipated from the outer surface of the heating cover 2 decreases. In this embodiment, the burner flame baffle plate 5 is formed into a curved shape, but it may be formed into an airfoil shape or a planar shape as shown in FIGS. 2 and 3.

In the present invention, a burner flame rectifying plate is provided in the gap between the inner cover and the heating cover, diagonally intersecting the center line of the burner, and the gap between the rectifying plate and the inner cover is made narrower as it goes downstream. , is bent toward the inner cover by the burner flame rectifier plate. Therefore, since the flame of the burner does not directly hit the heating cover, the life of the heating cover can be extended, and since the high-temperature gas effectively heats the inner cover, the material to be treated inside the inner cover can be uniformly coated more quickly. It can be heated to. Furthermore, the temperature of the heating cover including its lining is lowered, and the amount of heat radiated to the outside, which is wasted as a whole, is reduced, so energy can be saved.

Furthermore, since maintenance can be performed mainly on the burner flame rectifying plate, maintenance costs can be reduced and the time required for maintenance can also be shortened.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional view showing an embodiment of the present invention, Figs. 2 and 3 are views showing other embodiments, and Fig. 4 is an enlarged front view of a burner flame rectifying plate. FIG. 1... Inner cover, 2... Heating cover, 3...
Burners, 3a to 3f... Center line of burners, 5...
Burner flame rectifier, W... Gap, D... Distance between burner flame rectifier and inner cover.

Claims (1)

[Scope of utility model registration request] In a bell-shaped annealing furnace in which an inner cover is covered with a heating cover with a gap and a burner is provided on the heating cover, a burner flame rectifying plate is provided in the gap and intersects diagonally with the center line of the burner; A bell-shaped annealing furnace characterized in that the distance between the inner cover and the inner cover is narrower toward the downstream side.