JPH0361314A - Method for exchanging submerged tube in rh furnace - Google Patents

Abstract

PURPOSE:To easily execute repairing exchange of submerged tubes by executing the repairing exchange of submerged tubes in an RH type vacuum degass- refining furnace with eroded slag stuck by using a truck for repairing providing a drying device for refractory for repairing, slag cutter for outside part of the submerged tubes and receiving part for submerged tubes. CONSTITUTION:Edge 22 of the lower face slag cutter 15 fitted to a repairing truck 11 as possible to shift on rails 12 is positioned near the lower ends of both submerged tubes 26, 27 in the RH furnace 51 and the slag stuck to lower ends of the submerged tubes 26, 27 is removed with shift of the repairing truck 11 to front and back directions, and also the slag stuck to the side faces of submerged tubes 26, 27 is removed with the edges 28, 29. After blowing the refractory onto the inner eroded part and the outer damaged part of the submerged tubes 26, 27 with a press-in device 21, outer face blowing device 18 and inner face blowing device 19 into the submerged tubes 26, 27 with the inner face eroded, a burner hood 42 is ascended, and the fresh submerged tube is exchanged for the repaired submerged tube and the repaired refractory in the repaired submerged tube is heated and burnt with heating device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for replacing a dip tube in an R H furnace used for vacuum degassing.

[Conventional technology]

Rl-(The main parts of a furnace are composed of various subdivisions such as an upper tank, an intermediate tank, and a lower tank, and an immersion pipe.As is well known, the immersion pipe functions as a suction pipe and a discharge pipe for molten metal. ,
Since it is immersed in molten metal, slag etc. adhere to it and it is damaged by erosion, requiring early repair and replacement.

Therefore, the conventional method for replacing the immersion tube is to use a repair truck to remove the immersion tube to be replaced from the RH furnace, move the repair truck to a crane position, and then replace the immersion tube with a new one. Then, I moved it to the lower part of the RH furnace again and replaced the immersion tube.

(Problems to be Solved by the Invention) However, the above-mentioned immersion pipe weighs nearly 3 tons, and it requires a lot of effort to transport, remove, and install it on a repair trolley. There were hard spots.

Furthermore, it is necessary to replace the immersion tube within a short period of time, but since the immersion tube is heated to a high temperature after use, there is a problem in that it is difficult to quickly remove the heated immersion tube. Ta.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a method for replacing a immersion tube in an RH furnace, which allows the immersion tube to be replaced safely and within a short period of time.

[Means for Solving the Problems] A method for replacing dip tubes in an RH furnace according to the present invention in accordance with the above object includes a burner hood each having an elevating means and capable of receiving a pair of dip tubes. A method for replacing the immersion tube of an RH furnace using a repair truck equipped with a preheating drying device, a peripheral slag cutter having a immersion tube holder and a press-fitting device having an immersion tube holder, which are arranged on both sides of the device. In order to raise and replace the burner hood of the preheating drying device, the immersion tube was moved to i! Then move the repair trolley and install the immersion tube to be replaced on one side of the lower tank of the RH furnace, and then move the repair trolley. The dip tube holder on the other side is configured such that a dip tube placed in the section for replacement can be attached to the other side of the lower tank.

[Effect]

In the method for replacing a dip tube in an RH furnace according to the present invention, the dip tube is replaced using a repair cart having a preheating drying device, a peripheral slag cutter, and a dip tube support section.

In this case, the burner hood that can receive the dip tube can receive the pair of dip tubes, so the dip tube to be replaced is inserted and placed on this burner hood, but 1. In this case, even if the dip tube is at a high temperature on the plate, the burner hood provides a heat shield, so the work can be carried out safely and the dip tube can be held.

Next, move the repair trolley from side to side and attach the new immersion pipe that is placed in the immersion tube holder on one side to the lower tank, then move it further in the other direction and place the immersion tube holder on the other side in the section. Since the existing dipping pipe is attached to the lower tank, the distance the repair trolley has to move can be reduced.

〔Example〕

Next, examples embodying the method of the present invention will be explained,
It is provided for understanding the present invention.

Here, FIG. 1 is a plan view of a repair truck for an RH furnace used in the method of the present invention, FIG. 2 is a side view of the same, FIG. 3 is a sectional view of a preheating drying device attached to the repair truck, and FIG. The figure is a cross-sectional view of the outer circumferential slag cutter device installed on the repair truck, Figure 5 is a cross-sectional view of the press-fit device installed on the repair truck, and Figure 6 is a cross-sectional view of the press-fitting device installed on the repair truck.
The figure is a work process diagram for explaining a method of replacing a immersion tube in an RH furnace according to the method of the present invention.

First, the repair truck 11 used in one embodiment of the method of the present invention will be explained with reference to FIGS. 1 and 2. The repair truck 11 has the same rail 1 as the ladle truck used for normal work
I can now run on 2! A cable winding fa 13 for supplying power and the like and a hose winding machine 14 for winding air hoses and water hoses are provided on the side.

In addition to the preheating drying device 10, the repair trolley 11 includes a lower slag cutter 15 and an outer slag cutter 16 of the immersion tube that constitute the slag cutter device, and a television camera device 17 for viewing the melting state inside the RH furnace. , an outside spraying device 18 that constitutes the spraying device that is mounted on the same trolley as the TV camera device 17, an inner surface spraying device 19 that makes up the spraying device, and a material supply device 20 that supplies spraying material to these devices. And, press-fitting the refractory into the inside of the immersion pipe! 21, and an opening/closing sliding deck 52 for patching work.
It is equipped with

The lower slag cutter 15 attached to this repair cart 11 has a frame body 23 with blades 22 lined up on the upper end and guides arranged at the front and rear, and electric cylinders 24 and 25 on both sides for raising and lowering the frame body 23. The blades 22 arranged in parallel at the upper end of the frame are connected to the dip tube 26.2 of the RH furnace.
By reciprocating the repair cart 11 back and forth so that it coincides with the vicinity of the lower end of the dip tube 7, slag adhering to the lower end of the dip tube 26, 27 is removed.

As shown in FIG. 4, the outer slag cutter 16 has an expansion/contraction means 3 that laterally expands/contracts opposing blades 28, 29 which are arranged parallel to the outer diameter of the dip tube 26, 27 and the radius of curvature between the passages.
0, a lifting device 32 that raises and lowers the nuclear force 28, 29 together with an expanding/contracting means 30, and a rotating device 33 that rotates the whole, and is arranged exactly in the center of the immersion tube 26 (27 is the same). After stopping the repair trolley 11 and raising the entire body to a predetermined height, the blade 28.
29 is determined, and by rotating and moving up and down the nuclear force 28 and 29 in contact with the dipping tube 26, the slag adhering to the periphery of the dipping tube 26 is removed.

A support frame 34 is placed over the top of the outer slag cutter 16, and a dipping tube 35 is placed on the top so that it can be moved up and down and rotated.

On the other hand, the television camera device 17 is placed on a truck 36 that runs perpendicular to the traveling direction of the rail 12, and in addition to the television camera device 17, an external spraying device 18 is disposed on the truck 36.

The inside of the RH furnace 51 can be observed by means of the television camera device 17, and the outer surfaces of the dip tubes 26, 27 can be repaired by means of a device 18 for spraying the outer surfaces.

Then, in the center of the repair truck 11, the inner surface spraying device 1
The inner surface spraying device 19 is attached to the tip of a vibrator 37 and can be moved up and down and rotated by a motor (not shown), and the repair material sprayed from the tip can be used to spray repair material into damaged immersion pipes 26 and 27. It can be sprayed anywhere.

The material supply device 20, which is attached to the device 18 for external surface spraying and the device 19 for internal surface spraying, which constitutes the above-mentioned spraying device, is provided with a butterfly valve at the top, stores the repair material inside, and has a material cutting device at the bottom. This is a well-known construction with a tank installed in which the repair material is conveyed by means of compressed air, mixed with water along the way, and the top spray is fed to a nozzle.

A press-fit device 21 is provided at the end of the repair cart 11, and the cough press-fit device 21 is connected to the dip tube 2 as shown in FIG.
6 (27) A cylindrical body 38 to be inserted into the inside of the cylindrical body 38
The lifting frame 4 is raised and lowered by a lifting device 39 that raises and lowers the
0, and a material supply pipe disposed inside the cylinder 38 whose discharge port coincides with the outer surface of the cylinder, the lower part of either of the dip tubes 26 and 27 to be repaired. To,
After arranging the cylindrical body 38 with its axes aligned, it is raised to bring the lower flange of the cylindrical body into contact with the lower end of the immersion pipe 26.27, and then a repair material is applied to the material supply pipe using a hose (not shown). is poured in and discharged from the tip to the outside of the cylindrical body 38 to fill and repair the damaged area.

A support seat 41 is attached to the upper part of the elevating frame 40, and a dipping pipe is attached to the upper part! It is now possible to carry 31t. Incidentally, openable and closable sliding decks 52 for patching work are provided on both sides of this press-fitting device 21, so that local damage to the outside of the immersion tubes 26, 27 can be repaired by applying putty.

On the other hand, the device 18 is used to spray the outside surface, and the device 119 is used to spray the inside surface.
Alternatively, a preheating drying device IO is attached to the repair truck 11 in order to dry the repair material supplied by the press-in device 21 and to preheat the RH furnace. As shown in FIG. 3, the preheating drying device 10 includes an upper burner hood 42, a pedestal 43 for mounting the burner hood 42,
An electric cylinder 44 constituting a central elevating means, an internal heating burner (not shown) disposed in each of the left and right holes of the burner hood 42, an elevating means for the internal heating burner, and an electric cylinder provided at an intermediate portion of the burner hood 42. It is configured with an external heating burner 45.

The burner hood 42 is provided with a space 46 having a bicircular cross section as shown in FIG. 3, into which the dip tube 26.27 is completely inserted.
The mounting flanges 47, 48 of are adapted to abut the upper end of the burner hood 42.

The external heating burner 45 is a conventional oil burner, which blows out combustion gas into the middle part of the immersion tube 26.27 to heat the outside of the immersion tube 26.27 by a swirling flow.

When installing the burner hood 42 to which this external heating burner is attached, the mount 43 is attached to the surrounding fixed mount 4.
The burner hood 42 is mounted so as to be vertically movable via a guide member (not shown) attached to the burner hood 9, and an electric cylinder 44 is mounted at the center as shown in FIG. There is.

Subsequently, using this repair trolley 11, the immersion pipes 26 and 27 are
To explain how to perform the replacement work with reference to FIG. 6, first, place the new immersion tube 50 on the seat 41 of the press-fitting device 21, and place the new immersion tube 50 on the pedestal 34 of the external slag cutter I6. With the new dip tube 35 loaded, as shown in FIG.
Move 1.

Thereafter, the electric cylinder 44 of the preheating drying device IO is driven to raise the burner hood 42 so that its tip is supported on the mounting flange 47, 48, and
．． 27 is removed from the RH furnace 51, placed on the burner hood 42, and lowered as shown in FIG. 6(B). The dip tubes 26.27 are thereby enclosed by the burner hood 42, so that the heat from the dip tubes 26.27 is shielded, making it easier to work around them.

Next, move the repair cart 11, and as shown in FIG.
0 is pushed up by the lifting device 39, a new immersion pipe 50 is attached to one side of the RH furnace 51, and finally the repair cart 11 is moved as shown in FIG. 6(D), and the receiver is placed on the pedestal 34. The immersion tube 35 is pushed up by the lifting device 32 and attached to the other side of the RH furnace 51, thereby completing the replacement of the immersion tube.

〔Effect of the invention〕

As is clear from the above explanation, the method for replacing a dip tube in an RH furnace according to the present invention is carried out by attaching the dip tube to be replaced to the burner hood of the preheating drying device. Heat is shielded and work can be done quickly and safely with the removed immersion pipe still on the repair trolley.

[Brief explanation of drawings]

Fig. 1 is a plan view of a repair cart for an RH furnace used in the method of the present invention, Fig. 2 is a side view of the same, Fig. 3 is a sectional view of a preheating drying device attached to the repair cart, and Fig. 4 is a repair cart. FIG. 5 is a cross-sectional view of the outer periphery slag cutter device attached to the truck, FIG. 5 is a cross-sectional view of the press-fitting device attached to the repair truck, and FIG. 6 is for explaining the method of replacing the immersion tube in the RH furnace according to the method of the present invention. This is a work process diagram. [Explanation of symbols] 1O・---- One child heat drying device, 11----
・Repair trolley, 12---rail, 13--
・-Cable winder, 14--Hose winder, 15---Lower slag cutter, 16-
------・-・Outer slag cutter 17 --- Television camera device, 18--・-・・・External image spraying device, 19
−・−・Inner surface spraying equipment, 20・−・−Material supply device,
21-------Press-fitting device, 22---1----
-Blade, 23...--Frame, 24.25...--
-Electric cylinder-226, 27--Immersion tube, 28
．． 29---Blade, 30--Expansion/contraction means, 32-
・・・・・Elevating device, 33・・・・・One rotation device, 34・・・・The receiver is a mount, 35・・・・・One immersion tube, 36−・・−−m - Trolley, 37...-- Vibrator for spraying, 38-- Cylindrical body, 39-- Lifting device, 40-- Lifting stand, 41-...・−
・・・・Receiver is seat, 42・−−−−−・−Burner hood, 43・・−−−−・・Mount is mounted on frame, 44・・−・
・・Electric cylinder, 45-・・・External heating burner, 4
6.------ Space, 47.48--Flange mounting, 49--Fixed frame, 50.-
---1.--Immersion tube, 51--.RH furnace, 52-.
---m-・-Slide deck

Claims (1)

[Claims] (1) A preheating drying device each having an elevating means and a burner hood capable of receiving a pair of dip tubes, and an outer periphery slag cutter and a dip tube receiver disposed on both sides thereof, each having a dip tube receiver. A method for replacing a dipping tube of an RH furnace using a repair truck equipped with a press-fitting device having a press-fitting device, the method comprising: raising a burner hood of the preheating drying device, placing the dipping tube thereon for replacement, and removing the dipping tube; Next, the repair cart is moved and the immersion tube to be replaced placed on the immersion tube receiver on one side is attached to one side of the lower tank of the RH furnace, and then the repair cart is moved and the immersion tube on the other side is installed. A method for replacing a dip tube in an RH furnace, comprising attaching a dip tube to be replaced placed on a receiving part to the other side of the lower tank.