JPH0629449B2 - How to repair a hot metal carrier - Google Patents

Description

The present invention relates to a method for repairing a hot metal carrier for carrying hot metal.

(Prior Art) There is a hot metal carrier for transporting hot metal from a blast furnace to a steelmaking plant. As the hot metal carrier, a submarine-shaped tilting iron-skin container lined with refractory bricks is provided at both ends of the trunnion. There was one that was rotatably loaded on a pair of trolleys by an axis. A furnace opening for receiving or discharging hot metal is provided at the upper center of the iron skin container.

In a normal use state, the hot metal carrier is supported by trunnion shafts on both sides, that is, in a state of supporting both ends. It tends to bend.

The hot metal carrier that has been used for a long period of time yields due to the above load and causes permanent bending (strain). In the case where the outer surface iron skin of the iron piggy container of the hot metal carrier in such a state causes melt damage with perforation or deformation or deterioration due to the hot metal due to malfunction during transportation of the pig iron or trouble during transportation, The section has a smaller section modulus due to a section loss, resulting in more bending.
In some cases, the iron skin container comes into contact with the trolley frame, making it impossible to invert the hot metal carrier and rendering it unusable.

Conventionally, with regard to the molten pig iron carrier that has become unusable due to the melting damage, the iron-skin container was once removed from the dolly and a repair request was made to the manufacturer. On the manufacturer's side, the melted portion of the iron skin container is usually cut into a ring shape (so-called sliced shape), and a newly manufactured ring-shaped new iron skin is used to correct the passage cores on both sides of the trunnion shaft. The repair method of mounting and welding was adopted.

(Problems to be solved by the invention) However, according to the above-mentioned repair method, since the iron shell container is once completely divided, the cores of both trunnion shafts are repaired when the ring-shaped new iron shell is attached and repaired. It is difficult to completely align the centers, and a large amount of time is required for centering, which is disadvantageous in that repair costs are high. In addition, since the steel container is removed from the dolly and sent to the manufacturer, a long repair period of 6 to 7 months is required, and the hot metal carrying capacity during this period decreases.
Therefore, there is a drawback that the production amount decreases and the cost increases. Further, due to the long-term decrease in the number of hot metal trucks operating, there is a risk that production activities may be hindered, for example, other hot metal trucks may have to be used without being sufficiently maintained.

Therefore, in view of the above problems, the present invention takes a short time and
An object of the present invention is to provide a method for repairing a melted portion by accurately holding the cores of both trunnion shafts and correcting the bending of the entire iron skin container.

(Means for solving the problem) The technical means is that the pair of trolleys 3 are respectively rotatable with the trunnion shafts 6 provided at both ends of the tiltable iron-skin container 2 lined with fireproof bricks 5. It is a method of repairing a hot metal carrier 1 that is pivotally supported on a steel core and has a hot metal and hot metal blast furnace port 9 at the upper center, and corresponds to the erosion part such as perforation of the steel skin 4 of the steel container 2 After removing the refractory bricks 5 on the inner side of the part to be cut, the melted part is cut and opened in an upright position with the furnace opening 9 upward, and then the iron skin container 2 is tilted to the inverted position to form the iron skin container. 2
In this reversal posture in which the bending 11 of the entire iron skin container 2 is corrected by its own weight, in order to close the cutting opening, a repaired iron skin 12 of a corresponding shape prepared in advance is attached to the cutting opening and welded. The point is to repair the melted portion.

(Operation) According to the present invention, since the repair is performed without removing the steel container 2 from the carriage 3, the repair period can be shortened, and the wicks of both trunnion shafts 6 can be accurately held.

Further, when the steel container 2 is turned upside down, the bending 11 of the entire steel container 2 can be effectively corrected by the weight of the iron container 2.

(Embodiment) Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 is a hot metal carrier, an iron skin container 2 constituting a hot metal carrier main body for containing hot metal, and an iron skin. It is provided with a pair of carriages 3 that support both ends of the container 2.

The iron skin container 2 is composed of an iron skin 4 forming an outer surface and a refractory brick 5 lined on the inner surface side of the iron skin 4, and is formed in a so-called submarine shape by a central cylindrical portion and conical portions on both sides. ing.

Trunnion shafts 6 are provided at both ends of the iron-skin container 2, and are rotatably supported by bearings 7 on each carriage 3. Further, the trolley 3 on one side is provided with a rotation drive device 8 including a gap pinion, an electric reduction mechanism, and the like, and tilts the iron-skin container 2 around the axis of both trunnion shafts 6.

At the center upper part of the iron-skin container 2, a furnace port 9 is provided, which serves both as a receiving port and a tapping port.

10 is a rail for guiding the trolley 3.

Reference numeral 11 shows the bending caused by the dead weight of the iron skin container 2 and the weight of the hot metal.

Melt damage such as perforation is usually caused by troubles during pig ironing and transportation, and the site occurs near the furnace mouth 9. Since this portion corresponds to a portion where the bending moment of the steel case 2 is large, the bending 11 tends to increase when a cross-section loss occurs due to melting damage.

If the above melting damage occurs, remove the upper bearing box of the bearing 7 and bend the iron casing 2 with both bearings 7 and the trunnion shaft 6,
That is, check the center of the trunnion shaft 6. At this time, if the trunk of the trunnion shaft 6 is transcribed to the iron skin container 2 side,
It is convenient because the lead can be confirmed quickly and accurately as in the subsequent process.

Next, the refractory bricks 5 on the inner surface side of the steel skin 4 corresponding to the melted-down portion are removed. At this time, it is only necessary to remove the area of the melt-damaged portion and the peripheral portion thereof, and extensive removal is not preferable because repair costs are increased.

After that, the melted portion is cut and opened in an upright posture with the furnace opening 9 facing upward. It is preferable that the range of this cutting opening is at least 3 times the plate thickness of the steel shell 4 from the melting point. In addition, even if it has a complicated melting loss shape, it is necessary to make it as square, circular or elliptic as possible, and to cut and open the target shape in the circumferential direction with respect to the center line of the furnace opening 9 It is preferable in that it does not cause bending.

After cutting and opening, check for harmful notches such as gas notches on the periphery of the opening, especially at the corners.
Is rotated 180 degrees to the inverted position. At this time, since the cutting opening is located in a portion where the bending moment is large, the section modulus is reduced, and the bending 11 of the entire iron-sheath container 2 is easily corrected by the weight of the iron-skin container 2. Become.

In this inverted posture, the repair iron skin 12 manufactured in a shape corresponding to the cutting opening in advance is attached to the cutting opening,
Weld and join.

After that, the refractory bricks 5 may be lined on the inner surfaces of the steel skins 4 and 12.

According to the above repair method, the repair work can be performed without removing the iron-skin container 2 from the trolley 3, the repair period can be shortened, and the cores of both trunnion shafts 6 can be accurately held. 2 The bending of the whole can be corrected. Since the repair period is short, the repair cost can be reduced, the carrying capacity of the wire welding carrier 1 can be prevented from being lowered, and the spare wire welding carrier 1 need not be purchased.

For example, in the present embodiment, a cutting opening is formed with a length of 2000 mm in the axial direction and a length of 6000 mm in the circumferential direction.
When rotated 180 degrees to the inverted posture, the maximum bending 11 at the center was 43 mm in the upright posture, but after reversing it became 8 mm, which means that the weight of the iron container 2 could be corrected by 35 mm. Then, after the repaired iron shell 12 was welded and joined, the bending 11 was 13 mm when it was put upright again. Therefore, it was possible to correct the bending of 30 mm. In addition, the period used for repair was less than 1 month in total, and the repair period was shortened by about 5 to 6 months as compared with the conventional method.

The melted portion is large and the cutting opening length is 1/3 to 2 in the circumferential direction.
When it reaches to / 3, the repaired iron skin 12 is divided into three parts, the central part is welded to the first to restrain the whole, and then both sides are welded and joined, then twisting or bending It is effective in the correction and control of.

Further, even if the melted portion is small, if the bend 11 is large, the bend 11 can be bent more effectively by enlarging the cutting opening in the circumferential direction.
Can be corrected. Further, by applying an appropriate load at a position symmetrical with the furnace opening 9 in the inverted posture and repairing the bend 11 in a corrected state, it is possible to more effectively correct the bend 11.

Further, even when melting damage does not occur and it becomes unusable due to the increase in the bend 11, according to the same repair method as described above,
There is an advantage that bend 11 can be corrected.

(Effects of the Invention) According to the present invention, after removing the refractory bricks in the vicinity of the erosion part without removing the iron skin container of the molten pig iron carrier that has become unusable due to erosion damage, This is a repair method in which the repaired iron skin is welded and joined in a state where the damaged portion is cut and opened, and then the iron skin container is turned upside down and the entire bend is corrected by the weight of the iron skin container. As a result, the trunnion shafts of both trunnion shafts can be held with high accuracy, and the bending of the entire iron skin container can be corrected.

[Brief description of drawings]

FIG. 1 is a side view of a hot metal carrier as an embodiment of the present invention. 1 ... hot metal carrier, 2 ... steel skin container, 3 ... truck, 4 ...
… Iron skin, 5 …… Fireproof brick, 6… Trunnion shaft, 9…
… Furnace mouth, 11 …… Bend, 12 …… Repair iron skin.

Claims (1)

[Claims] 1. A trunnion shaft provided at both ends of a tilting iron-skin container 2 lined with refractory bricks 5 on a pair of carts 3.
6 is a method of repairing a hot metal carrier 1 in which each is rotatably rotatably supported and has a furnace port 9 for receiving and tapping iron in the upper central part, such as perforation of a steel skin 4 of a steel container 2 After removing the inner side refractory brick 5 of the part corresponding to the erosion part, cut and open the erosion part in an upright position with the furnace opening 9 upward, and then tilt and invert the steel container 2 In this posture, the bending of the entire iron-sheath container 2 is corrected by the weight of the iron-skin container 2, and in this inverted position, the repaired iron-sheath 12 of the corresponding shape prepared in advance is cut to close the cutting opening. A method for repairing a molten pig iron carrier, characterized by repairing a melted portion by mounting it on a welded portion and welding it.