JPH06430Y2 - Seal plate for furnace lid of coke oven - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a seal plate for a furnace lid of a coke oven assembled by welding.

[Conventional technology]

When coal is carbonized by a coke oven, the raw material coal is charged into the furnace to insulate the inside of the furnace and shut off the outside air, or it is attached to the opening of the coke oven that pushes the carbonized coke out of the furnace. A seal plate is attached to the furnace lid.

The knife edge portion of the seal plate is pressed against the surface of the furnace lid frame sheet by the pressing force of the pressure welding device attached to the furnace lid. As such a furnace lid sealing structure, for example, "3rd Edition Iron and Steel Handbook II, Ironmaking and Steelmaking" (Showa
Some examples are given on page 184 of the 3rd edition of Maruzen Zenkai Co., Ltd. on September 20, 1955. This prevents the in-furnace gas and tar generated during carbonization from spouting outside the furnace, and maintains a constant pressure inside the furnace. From this point, the seal plate plays the most important role in the sealing structure of the furnace lid.

As the seal plate, a concave plate may be used due to the structure of the coke oven and the oven lid. Since the concave seal plate has a long cantilevered portion extending to the knife edge, it has excellent flexibility and allows the furnace lid to be attached in an excellent close contact state. In addition, since tar enters the inside of the furnace for a predetermined distance from the furnace wall where the temperature drop easily occurs, the adhered tar and the like can be easily removed.

The seal plate having such a shape is manufactured by press-forming a plate-shaped stainless steel or the like using a drawing die when the size of the concave die is small. However, when the size of the concave mold is large, the material is likely to break during pressing. Therefore, a method of assembling the seal plate by welding the plate materials forming the respective surfaces to each other is adopted.

FIG. 3 (a) is a sectional view showing a furnace lid incorporating a conventional seal plate, and FIG. 3 (b) is a perspective view showing a seal plate assembled by a conventional welding method.

As shown in FIG. 3A, the furnace lid main body a has a concave cross-sectional shape in which both ends are projected to the outside of the furnace body, and the concave bottom portion is slightly inserted into the furnace. A seal plate b is provided so as to surround the lower portion of the furnace lid body a. A knife edge c is attached to the tip of the seal plate b, and the knife edge c is pressed against the furnace frame sheet surface d by the elastic force of the seal plate b, so that the furnace lid is closely sealed to the furnace frame. Be seen. On the back surface of the furnace lid main body a, a brick e facing the inside of the furnace is fixed by a supporting metal f.

Such a concave seal plate b is manufactured by welding a side plate i to a main plate h that is bent so that a recess g is formed in the center, as shown in FIG.

[Problems to be solved by the invention]

When assembling the concave seal plate by welding the plate materials in this way, it is unavoidable that the welding line 1 comes to the corner portion as shown in FIG. The corner portion is a portion where stress is likely to be concentrated when the seal plate is attached to the furnace lid body and used. Therefore, stress concentration occurs at a portion where the structure is changed by welding, and the seal plate is easily broken. Further, since the knife edge c is pressed against the oven frame sheet surface d of the coke oven, the plate material around the corner portion needs to be a thin plate having high flexibility. Even from this point, sufficient welding strength could not be maintained at the corners, and the durability of the seal plate was poor.

Therefore, the present invention has been devised to solve the problem at the corner portion, avoiding the welding line from coming to the corner portion, and relaxing the stress concentration at the corner portion to improve durability. An object is to provide an excellent furnace lid seal plate.

[Means for solving problems]

In order to achieve the object, a seal plate for a furnace lid of the present invention has a side plate and a middle plate having side edges welded to the side surface of a thick plate having a knife edge at the tip, and another side edge of the side plate and the middle plate. And a central recess formed by bending at a right angle in the opposite direction, and a part of the side plate and the middle plate that are in contact with the corner of the central recess are notched, and the corner piece is provided in the notched part. It is characterized in that the side plate and the middle plate are welded together.

〔Example〕

Hereinafter, the features of the present invention will be specifically described by way of examples with reference to the drawings.

FIG. 1 is a perspective view showing a seal plate according to an embodiment of the present invention, and FIG. 2 is an enlarged view of a corner portion thereof.

Also in this example, the seal plate 1 is composed of the side plate 2 and the middle plate 3. The side edge 2a of the side plate 2 is bent vertically and welded to the side surface of the thick plate 5 forming the knife edge 4. Further, a part 2b of the side plate 2 is bent in a direction opposite to the side edge 2a in a direction perpendicular to the side edge 2a to form a side wall of the central recess. Further, the central portion 2c of the side plate 2 becomes the bottom surface of the central concave portion. On the other hand, the middle plate 3
Is bent into a crank shape as shown in FIG. 2, and one end 3a thereof is welded to the side surface of the thick plate 5. The other end 3b of the middle plate 3 is one side wall of the central recess.

In such a seal plate 1, part of the side plate 2 and the middle plate 3 forming the corner of the central recess is cut out, and the corner piece 6 is arranged there. The corner piece 6 is a top plane 6a that forms the same plane as the main surfaces of the side plate 2 and the middle plate 3.
And a curved surface portion 6b continuous with the portions 2b and 3b of the side plate 2 and the middle plate 3.
With and. Then, the top flat surface 6a and the curved surface portion 6b are welded to the side plate 2 and the middle plate 3. As a result, the welding line 1 can avoid a corner portion where stress concentration is large.

The diameter D of the top flat surface 6a is preferably set to 30 to 100 mm in order to easily perform welding without giving a heat effect to the corner portion. When the diameter D is smaller than 30 mm, the welding line 1 approaches the stress concentration point in the corner portion, cracks easily occur in the welding portion, and the effect of the corner piece 6 is reduced. On the other hand,
When the diameter D exceeds 100 mm, the welding line 1 becomes long,
Not only the welding workability is deteriorated, but also the side plates 2 and the middle plate 3 are adversely affected by the welding heat.

Further, the curved surface portion 6b has a linear distance L from one end to the other end of 20.
It is preferable to make a chevron shape of -60 mm. This straight line distance L
Also, like the diameter D, the influence of welding does not appear in the corner portion, and the size of the corner piece 6 is set appropriately.

Further, it is preferable that the mountain-shaped top portion of the curved surface portion 6b be formed into a radius having a radius R of 10 mm or more in order to reduce stress concentration. When the radius R is less than 10 mm, the concentration of stress increases, and defects such as cracks are likely to occur. On the other hand, if the radius R exceeds 10 mm,
Since the stress is dispersed over a wide range, the resistance to stress cracking becomes large. FIG. 5 is a graph showing the change in the stress generated in the corner portion depending on the radius R.

As described above, by welding the side plate 2 and the intermediate plate 3 forming the central recess using the corner piece 6, it is of course that the welding line 1 does not come to the corner portion, and of course, the thermal effect caused by the welding. Section does not occur in the corner section. And
The stress concentrated on the corner portion is received by the corner piece 6. Therefore, stress concentration cracking at the corner portion is prevented, and the seal plate 1 having excellent durability is obtained. Also,
When niobium-containing stainless steel is used as the corner piece 6, it exhibits excellent resistance to stress corrosion cracking even in a corrosive environment containing chlorine ions.

[Effect of device]

As described above, in the present invention, the welding of the side plate and the intermediate plate through the corner piece at the corner portion prevents the welding line from reaching the corner portion. Therefore, the corner portion where the stress is concentrated is not embrittled due to the structural change caused by welding, so that the seal plate having excellent durability can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing a seal plate of an embodiment of the present invention, and FIG. 2 is an enlarged view of a corner portion thereof. On the other hand, FIG. 3 shows a conventional furnace lid and its seal plate, and FIG.
The figure is an enlarged view of a conventional seal plate, and FIG. 5 is a graph showing the effect of the radius R on the stress. 1: Seal plate 2: Side plate 3: Middle plate 4: Knife edge 5: Thick plate 6: Corner piece 6a: Top flat surface 6b: Curved surface l: Welding line D: Diameter of top flat surface 6a L: Linear distance of curved surface part R : Corner radius of curved surface

Claims (1)

[Scope of utility model registration request] 1. A side plate and a middle plate having side edges welded to the side surface of a thick plate having a knife edge at the tip, and a central recess formed by bending the other side edge of the side plate and the middle plate at right angles in opposite directions. And a part of the side plate and the middle plate that hits the corner portion of the central recess, and a corner piece provided in the notch portion, and the corner piece and the side plate and the middle plate are welded together. A seal plate for the oven lid of the coke oven.