JPS58188563A - Build up welding of seat surface of bell for blast furnace - Google Patents

Abstract

PURPOSE:To enable installation of a welding machine at low position and perform safe welding by rotating a bell held in upright state and performing build up welding after providing a welding machine installed outside of the bell seat face and a specified flux receiver in its lower part. CONSTITUTION:A cylindrical body 12 for supporting a bell is erected at the center of upper face of a turn table 11 and an upright bell 1 is placed on the upper end face of the cylindrical body 12 to cover it avoiding misalignment of the cylindrical body 12 and the bell 1. Main pillars 13 are erected on the outer periphery of the seat surface 1a of the bell 1 at posibions, for instance four positions, of equal angular distance, and rotatable upper and lower arms 14, 15 are provided. Further, a build up welding machine 8 and an endless coveyor type flux receiver 16 are installed at the tip. The surface 1a of the bell 1 rotated by the table 11 is preheated by a preheating burner 6 in the middle of welding nachines 8. At the same time, the flux receiver 16 is rotated along the outer periphery of the surface 1a at the same speed with rotation of the bell 1. The surface 1a is build up wedlded from the lower part to upper part successively to form a built up part 2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for overlaying the seat surface of a space-hearth bell.

There are two bell types, three bell types, etc. in the bell-type raw material charging device inside the top of the blast furnace. This is to distribute the gas evenly to the furnace and prevent the top gas from leaking.

The bell has a conical shape with an inclined surface of 53 degrees, and the role of the seat surface, which is the lower part of the inclined surface, is especially important, and the life of the bell is determined by the wear of this seat surface.

Therefore, as shown in FIG. 1, on the seat surface 1a of the bell l,
A wear-resistant weld build-up 2 is formed in advance, or a weld build-up 2 is repaired and formed on the seat surface 1a that has been worn due to use.

Conventionally, in overlay welding of the bell seat surface 1a, as shown in FIGS. 2 and 3, a tilting table 4 that is tilted by an arbitrary drive device is supported between bearings 3, and a A swivel table 5 is provided which is rotated by an arbitrary drive device, and the bell 1 is placed and fixed in the center of the swivel table 5.
As shown in the figure, the tilting table 4 is tilted to a required angle, the ridgeline of the inclined surface, which is the upper position of the tilted bell 1, is made horizontal, and the seat surface 1a, which is the lower position of the bell l, is heated by the preheating burner 6. Preheat to the required temperature, turn the swivel table 5 to make the preheating uniform, rotate the bell l, and then use the overlay welding machine 8 on the workbench 7 to heat the bell seat surface to the upper position. 1aK, weld build-up portions 2 were sequentially formed by submerged arc welding.

In this conventional overlay welding, the ridgeline of the inclined surface at the upper position of the tilted bell 1 is made horizontal, and the weld overlay part 2 is formed on the seat surface 1a at the horizontal upper position. There was a problem that welding was done in parts, which was difficult to work with and could be dangerous.

In addition, since the weld build-up portion 2 is formed on the seat surface 1a which is horizontally located at the - side, the welding area is limited, and therefore the number of welding machines 8 used for build-up is limited to one or two. , there was a problem of extremely poor efficiency.

Moreover, since the welding operator is exposed to the rising heat from the lower preheating burner 6, there is a problem in that the welding operator suffers from fatigue due to the hot air.

Furthermore, although the bell 1 is placed and identified on the swivel table 5, when it is tilted to a required angle, it is held in a so-called cantilevered position, and since it is rotated, the holding state is extremely unstable. was there.

The present invention was developed to solve various problems in conventional overlay welding of bell seat surfaces such as bell seats, and an example of its implementation will be described below with reference to FIGS. 4 to 8.

As shown in FIGS. 4 and 5, a bell supporting column 12 is erected at the center of the upper surface of the swivel table 11, and the vertical center line of the column 12 is aligned with the bell supporting column 12 so as to cover the column 12. so that the vertical center line of bell 1 coincides with the vertical center line of bell 1, that is, so that bell 1 is not centered.
The bell I in an erect state is placed at its top on the upper end surface of the column body 12.

At equal angular intervals on the outer periphery of the seat surface 1a of the bell (1), which is supported in an erect state by the pillar body 12, there are provided upper and lower swing arms 14.15 which are enabled. A welding machine 8 for overlaying is provided at the tip, and a welding machine 8 for overlaying the valley is installed at the tip of the lower rotating arm 15 ('ζ Endless conveyor 2nd axis receiver) 6.
A preheating burner 6 covered with a heat insulating cover 6a is disposed at each intermediate position of the disposed position, and while the bell l supported in an erect state is rotated at a required speed by a swivel base 11, While preheating the bell 7-toe 1a with the preheating burner 6, the endless conveyor second support 16 is rotated at the same speed in the rotation direction of the bell 10 along the outer periphery of the sheet surface 1a, and the overlay welding is performed. The machine 8 and the endless conveyor set flux receiver 16 perform overlay welding on the sheet surface 1a sequentially from the bottom to the top, thereby forming the weld overlay portion 2 on the sheet surface 1a.

In addition, in order to provide the overlay welding machine 8 on the upper rotating arm 14, for example, as shown in FIG.
By rotating the handle 17a, the terminal rod L is attached to the tip of 4.
The sliding block 17c is connected to the upper rotating arm 1 through the
4 (A position adjusting device 17 is provided which is slidable in the front and back direction, and the sliding block 17c of this position adjusting device 17 is slidable via the terminal rod 1.8 b by rotating the handle 1.8 a. A position adjustment device 18 is provided in which the block 18c is slid diagonally in the 1F direction with respect to the upper rotating arm 14, and the sliding block 18c of the position adjustment device 18 is connected to the sliding block 18c via the support rod 9 for overlaying. A welding machine 8 is provided, and the angle of the torch 8a of the welding machine 8 for overlaying with respect to the seat surface 1a can be adjusted by rotating the attachment part of the support rod 19 and the welding machine 8 for overlaying, or by adjusting the position with the position adjustment device 17. It is possible to adjust the A by rotating the attachment part of the adjusting device 18, etc.

In FIG. 11, 20 is a flux storage device, 20a is a flux supply hose, 21 is a flux recovery device, and 21a is a flux recovery hose.

As shown in the figure, the end of the lower rotating arm 15 is provided with a VC1 unit & 15a for angle adjustment, and this base plate 15a is installed at the tip of the lower rotating arm 15. -L, as shown in FIG.
A heat insulating material 16c such as asbestos is covered between the outer circumferential surface of the chain 16b and the outer peripheral surface of the chain 16b, and the sprocket wheel 16a is connected to an arbitrary It is designed to be rotated by a drive device, and the endless conveyor complete flux receiver ■6°.In particular, the heat insulating material 16c is attached to the sheet surface 1a.
The length is such that it comes into contact with the top surface 1a of the bell l that rotates once from the overlay welding until the weld metal solidifies, and prevents the flux from flowing down and the bead from flowing down during overlay welding. It is for the purpose of

Furthermore, on the top surface of the upper swing arm 14,
Sixth [As shown at the beginning, an arm 22 is provided that protrudes from the upper part it of the torch 8a, and a copying roll 22a that contacts the sheet surface 1a is provided at the tip of this arm 22. core runout or expansion of bell 1 due to heat.

This is to prevent variations in the distance between the sheet surface Ja and the torch 8a due to shrinkage, etc., and to perform stable overlay welding.

However, the wire for submerged arc welding (diameter 4.
8 diameter) and flux, welding current 400 ~
450A, welding voltage 30-35V.

Welding speed (circumferential speed of sheet surface 1a) 430 to 470 wI/
/wR, with the protruding length of the wire 25 to 30 +a+i, as shown in FIG.
And the aiming position of the torch 8a is 1 to 1 inch closer to the lower bead than the bell penetration boundary line at the lower bead.
When overlay welding was carried out using 5, u and a pass pitch λ of 171J, the penetration was good and a weld overlay part 2 without welding defects could be formed.

By the way, if the inclination angle and target position of the torch 8a are out of the above conditions, the welding between the sheet surface 1a and the overlay bead will be poor and it will be easy to peel off, and the molten metal will drip down and the normal bead shape will be distorted. Care must be taken to prevent welding defects such as large racks and blowholes.

Especially if the target position of the torch 8a is off, the seat surface 1a
Care should be taken to avoid poor welding between the weld and the lower weld bead, resulting in a large defect.

As described above, the present invention includes a welding machine for overlaying, which rotates a bell held in an upright position at a required speed while keeping it in an upright position, and a welding machine for overlaying that is disposed on the outside of the bell seat surface. At the lower part of the torch, weld the bell seat surface sequentially from below upward using a flux receiver set of an endless conveyor that is arranged to rotate at the same speed in the rotational direction of the bell along the outer periphery of the bell seat surface. As a result, the overlay welding machine can be installed at a low height, and the conventional welding work at a high place can be eliminated, so that the welding work can be performed safely.

Since overlay welding is performed on the seat surface with the first bell in the IE upright position, overlay welding machines can be installed at equiangularly spaced locations on the outer circumference of the seat surface, for example, at four locations. Therefore, overlay welding on the /-to surface can be performed with high efficiency.

Furthermore, since the preheating burner can be disposed at an intermediate position between each overlay welding machine, the welding operator is not directly exposed to the heat of the preheating burner as in the past, and the problem of fatigue due to hot air can be eliminated.

Furthermore, the endless conveyor set flank receiver provided at the lower part of the torch can prevent the flux from flowing down and the beads from flowing down.

[Brief explanation of drawings]

Figure 1 is a vertical cross-sectional view showing a general example of a blast furnace bell;
FIG. 3 is an explanatory diagram showing conventional overlay welding, FIG. 4 is a schematic vertical sectional view showing an example of implementation of overlay welding of the present invention, FIG. 5 is a schematic plan view of the same, and FIG. FIG. 4 is an enlarged front view showing details of the main parts, FIG. 7 is a plan view showing an example of an endless conveyor complete set of flanks, and FIG. 8 is an explanatory diagram of overlay welding conditions according to the present invention. Patent applicant: Kawasaki Steel Corporation Patent applicant: Special Electrode Co., Ltd.

Claims (1)

[Claims] The bell held in an upright state is rotated at a required speed while the bell is in the upright state, and a welding machine for overlaying installed on the outside of the bell seat surface and a torch F of this welding machine for overlaying are connected. At the 17th point along the outer periphery of the bell seat surface, the bell note surface is welded sequentially from below to above using the endless conveyor 2 flank bridge, which is arranged to rotate at the same speed in the rotation direction of the bell. A method for overlaying a sheet surface of a blast furnace bell, characterized by: