JP2564129B2 - Preheating and drying equipment for immersion pipe in vacuum degassing equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a preheating and drying device for a dip tube in a vacuum degassing apparatus, and more specifically, it is attached to the inner surface of the dipping tube in the vacuum degassing apparatus during the steelmaking process. This is related to the preheating and drying device for the immersion pipe which is equipped with measures to prevent the metal from falling.

<Prior Art> In a conventional vacuum degassing apparatus 1, as shown in FIG. 4, a furnace body (hereinafter referred to as a furnace body) 2 having a circular cross section is used for the purpose of preheating and drying the immersion pipe 5 to which a metal 5'is attached. It is well known that a device in which a plurality of high-speed burners 6 are linearly arranged at a right angle to the axial center of the furnace body 2 and a manhole (cleaning port) 9 is provided in the lower part of the device is used. is there.

<Problems to be Solved by the Invention> However, since this device has the above-mentioned configuration, when the dipping pipe 5 is interposed on-line in the device as shown in the figure, the dipping pipe 5 is grounded on the inner surface thereof. Gold adheres and interferes with the inner cylinder 3 to make it difficult to set the immersion pipe in a proper position, and also damages the furnace body due to such deposits (bare metal) falling and lining material peeling off. Of course, since the flow of exhaust gas is hindered by the accumulation of the fallen objects, it is often necessary to repair damaged parts including inspection of the furnace body,
Therefore, at the same time as the increase in the required cost, the production efficiency has been lowered.

From this point of view, how to improve the immersion device has become an urgent issue.

<Means for Solving Problems> As a result of intensive research to solve the above problems, the inventors of the present invention have found that for solving the problems, the preheating of the immersion pipe in the vacuum degassing apparatus and the configuration of the drying apparatus. And mechanism, especially (a) ideal high-speed burner to be installed around the furnace body, (b)
We came to the conclusion that the internal cylinder structure, (c) the collection of fallen objects on the hearth, and (d) the buffer mechanism should be reconsidered.

Here, the present inventors have succeeded in solving the above-mentioned problems all at once by recognizing the above-mentioned various points and configuring the gist of the present invention as follows, and completed the present invention. That is, a plurality of high-speed burners are arranged linearly and tangentially on the outer periphery of a furnace body having a circular cross section, and an inner cylinder having a side cone-shaped head whose center is the shaft center of the furnace body in the furnace body. , The head of the inner cylinder is hung vertically, the hearth is formed on an inclined surface, a manhole is provided in the lower part of the hearth, and a buffer mechanism is provided at an appropriate number of points in the furnace frame.

The object of the present invention is to reduce the atmospheric temperature difference between the inner and outer surfaces of the dip tube (described later) by improving the effects of radiant heat and convective heat transfer (described later), and at the same time shorten the preheating and drying times and extend the recovery period of the falling deposits. It is to provide a preheating and drying device for a dip tube in a vacuum degassing device, which is possible.

Therefore, in the above, a plurality of high-speed burners are arranged tangentially on the outer periphery of the furnace body in a straight line (upper and lower two stages:
(See Figs. 1 and 2) What happens is that the hot gas injected at high speed from the burner into the furnace will swirl and drop along the inner surface of the furnace, but this hot gas naturally falls in the furnace. A swirling vortex is formed between the outer peripheral surface of the immersion pipe located on the outer peripheral portion of the inner cylinder and the peripheral surface of the furnace body, descends in the direction of the arrow and rises, and the immersion pipe with deposits (metals) attached This is for the purpose of further improving the heat transfer effect by uniformly preheating and drying from the peripheral surface. Also, in the internal configuration, the head has a conical side surface, which is detachably fixed to the inner cylinder (base). , And hang it in the furnace with its head facing upward (see Fig. 1 and 2)
What was done was that the high-speed hot gas from the burner consciously attached the metal to the inner peripheral surface of the dip tube, preheats the dip tube uniformly from the inside and outside, and exhausts the exhaust heat afterwards. This is because it is advantageous to directly conduct the fluid to the outside of the system (heat exchange device etc.) along the conical surface of the head without lowering the flow velocity.

Furthermore, the fact that the hearth is formed on a slope means that even if there is a drop of the metal that adheres to the dipping pipe or peeling of the refractory material in the furnace as described above, those falling objects can be effectively slid and deposited in one place. At the same time, in order to prevent the flow of hot gas from the burner from being obstructed by the deposits, and the provision of a buffer mechanism at an appropriate number of points in the furnace frame means that the deposits on the immersion pipe, etc. This is for alleviating the impact on the inner cylinder and the furnace body caused by falling. As the cushioning member, a known heat-resistant cushioning material such as a drum-shaped member made of synthetic rubber may be used.

<Operation> The above technical means operates as follows.

As shown in FIG. 1, a plurality of high-speed burners are arranged on the outer periphery of the furnace body in upper, lower two stages and tangentially. Therefore, the hot gas injected from the burner into the furnace is A swirling flow is generated along the peripheral surface, descends between the outer peripheral surface of the immersion pipe located on the outer peripheral portion of the inner cylinder hung vertically inside the furnace and the peripheral surface of the furnace body, and rises to the immersion pipe with the metal attached. While contributing to the uniform preheating and drying from the inner and outer peripheral surfaces, the exhaust gas (hot gas) after preheating and drying is conducted to the outside of the system along the conical surface of the inner cylinder head without decreasing the flow velocity. Is possible. Also, since the hearth has a sloped surface and is of a chute type as shown in the figure, when the immersion pipe with the metal adhered is uniformly preheated and dried in the furnace body, the adhered metal will fall off and refractory materials, etc. Even if they fall off, the sliding of these fallen objects can be effectively made, and at the same time it is possible to deposit at one location. Moreover, since this deposition location is located below the immersion pipe, the hot gas from the burner There is no possibility that conduction will be obstructed by deposits, and furthermore, since a shock absorbing mechanism is provided at an appropriate number of places in the furnace body frame, the impact received by the inner cylinder and furnace body due to the fall of the immersion pipe deposits It absorbs well and the service life of both of them can be extended.

<Embodiment> An embodiment of the present invention will be described below with reference to the drawings in which the same portions are denoted by the same reference numerals.

In the figure, reference numeral 1 is a vacuum degassing apparatus, which is a furnace body 2
The furnace body 2 is a tubular body having a circular cross section, and a plurality of high-speed burners 6 are linearly and tangentially arranged on the outer periphery of the furnace body 2 in upper and lower two stages. (See FIGS. 1 and 3), and the furnace body 2
As shown in FIG. 2, a bottle top-like lid 2'having a circular cross-section with the same inner and outer diameters as the furnace body (base body) is attached to the top of the lid via a heat-resistant packing 2 "as shown in FIG. (Not shown)
It is fixed so that the conduction of exhaust heat from the burner (described later) 6 can be advantageously conducted. The burner 6 is set between the overhanging plate 6a fixed to the furnace body 2 and the pedestal 6b at both upper and lower stages as shown. Reference numeral 8 denotes a heat-resistant cushioning member, for example, a drum-shaped elastic body made of synthetic rubber, and the elastic body 8 is provided with a supporting member 11 'between the pedestal 6b and the overhanging pedestal 6c provided on the upper part of the furnace frame 11. It is inserted as shown in the figure to reduce the impact on the inner cylinder and the furnace body.

The inner cylinder 3 is a cylindrical body in which a conical head portion 4 having a conical side surface with the axis of the furnace body as an axis is detachably fixed, and the diameter thereof is 2
It has a smaller diameter than that of the above, and is vertically installed in the furnace body 2 with the head portion 4 facing upward, as shown in the drawing. The distance between the outer peripheral surface of the inner cylinder 3 and the inner peripheral surface of the furnace body 2 is Sufficient space is ensured for inserting the dipping pipe (described later) 5. Numeral 7 is a chute type hearth formed of a slope starting from the center of the furnace body 2 in the vertical direction. The inclination angle of the hearth is such that the metal 5'attached to the dip pipe 5 falls off or the refractory material 12 peels off. Is formed at an optimum angle for sliding, and a manhole 9 is provided at the front end thereof to advantageously take out the fallen object S accumulated on the portion. Reference numeral 10 is a lid for opening and closing the manhole 9, and the lid 10 is attached so as to be rotatable up and down as shown in the drawing from one end of the bottom portion of the inner cylinder as a base point. It can be opened and closed freely by making it electric.

In the figure, 12 is a refractory material, 13 is an inner cylinder indicating frame, 14 is a frame reinforcing member, and 15 is a frame reinforcing member.
Indicates a base frame for the inner cylinder support frame.

<Effects of the Invention> Since the present invention can fully exhibit the following unique effects, the practical benefits in the related industrial fields are remarkable.

Since a plurality of high-speed burners are arranged in a straight line on the outer periphery of the furnace in a tangential manner in opposite axes (for each of the upper and lower stages), the hot gas injected at high speed into the furnace is the inner cylinder hung vertically inside the furnace. Pre-heat the immersion pipe with a deposit (metal) attached to it from the inner and outer peripheral surfaces uniformly, as it descends in a swirling vortex between the outer peripheral surface of the immersion pipe located on the outer periphery and the peripheral surface of the furnace body, and ascends. It can be dried.

In the inner cylinder configuration, the head has a conical side surface, which is detachably fixed to the inner cylinder (base), and the head is directed upward into the furnace so that the high-speed hot gas from the burner is Preheat the dip tube uniformly from the inside
Not only does the exhaust heat after drying pass the outside of the system effectively along the conical head surface without reducing the flow velocity, but it also allows the conical head to be replaced if necessary. .

Since the hearth is formed in a chute type as described above, not only is it possible to deposit the metal in one place by sliding down the falling metal due to the dropping of the metal adhered to the dipping pipe and the separation of the refractory material. Since the deposition location is selected so as not to hinder the hot gas conduction from the burner, it is possible to further improve the hot gas conduction in the furnace.

Since the buffer mechanism is provided at an appropriate number of places in the furnace body frame, it is possible to effectively mitigate the impact on the inner cylinder and the furnace body due to the fall of the deposits on the immersion pipe.

As is clear from the above, the present invention improves the radiant heat and the convective heat transfer effect, so that the temperature difference in the atmosphere in the furnace is small,
Moreover, by installing a buffer mechanism, the life expectancy of the furnace body, including the inner cylinder, can be expected to be greatly extended. Furthermore, preheating and shortening of the drying time save energy, and the collection cycle of falling sediments can be extended to recover the deposits. At the same time, it can be expected that not only the labor saving but also the improvement of the production efficiency will be achieved.

[Brief description of drawings]

1 is a partially cutaway schematic explanatory view showing the structure of the present invention, FIG. 2 is a partially cutaway schematic explanatory view showing the top of the present invention as an enlarged cross section, and FIG. 3 is FIG. FIG. 4 is a partially cut-away schematic explanatory view showing an essential part of a conventional example, taken along the line XX. 1 ... Vacuum degasser, 2 ... Furnace body, 2 '... Lid body, 3 ... Inner cylinder, 4 ... Conical head, 5 ... Immersion tube, 5' ... Ingot, 6 ... Burner, 7 …… Hearth, 8 …… Cushioning member, 9 …… Manhole, 10…
… Enclosed lid, 11 …… Frame, 12 refractory material, 13 …… Inner cylinder support frame, 14…
… Frame reinforcing member, 14 ′ …… Bottom reinforcing material, 15 …… Base frame, s… Falling object.

Claims (1)

(57) [Claims] 1. An inner cylinder having a plurality of high-speed burners arranged linearly and tangentially on the outer periphery of a furnace body having a circular cross section, and having a conical head portion on the side of the furnace body as the axial center of the furnace body. The vacuum is characterized in that the head of the inner cylinder is hung vertically and the hearth is formed on an inclined surface, a manhole is provided in the lower part thereof, and a buffer mechanism is provided at an appropriate number of places in the furnace frame. Preheating and drying equipment for immersion pipe in degassing equipment.