JPS616582A - Arc furnace equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to arc furnace equipment that substantially increases the operating rate of the furnace and reduces the electric power consumption rate.

[Prior art] In steelmaking using an arc furnace, scrap is charged as a raw material, but before charging, the scrap is preheated by exhaust gas discharged from the melting furnace during melting. There is.

In conventional arc furnace equipment, scrap is once received in scrap buckets 1~, the exhaust gas from the melting furnace is lowered to the desired temperature and preheated, and then the scrap is moved from the preheating position to the scrap charging position. It was charged into the melting furnace,
Such a conventional arc furnace has the following drawbacks.

(i) Because the preheating tank is a scrap tank, high temperature exhaust gas cannot be introduced, so WzH is used to adjust the exhaust gas temperature.
However, the preheating temperature cannot be made too high.

O] The life of the preheating tank is short.

(b) Scrap after preheating is carried out by moving the scrap bucket to the charging location, so a trolley or crane is required to support and move the scrap bucket, which makes the equipment large-scale and takes time to charge the scrap.

[Problems to be Solved by the Invention] In view of the above-mentioned circumstances, the present invention effectively utilizes waste heat during melting to lower the electricity consumption rate for melting and shorten the melting time.
Moreover, it shortens the process and improves the operating rate of the furnace.

[Means for solving the problems] The present invention includes two melting furnaces and two scrap buckets,
Scrap is melted in one melting furnace, the exhaust gas is led to another melting furnace for high-temperature preheating, the scrap is further led to a scrap bucket, and the scrap is preheated at a low temperature, and the remaining scrap bucket is charged and the melting position is and the preheating position are changed each time one melting operation is completed.

[Example] The present invention will be described in detail below with reference to the drawings.

A running rail 1.2 is laid in a T-shape, and four bogies 3, 4, 5.6 are mounted on one rail 1 so that they can run freely, and a melting furnace 7 is mounted on the middle bogie 3.4. .8 is provided so as to be tiltable, and scrap buckets 9.10 are placed on two carts 5.6 on both sides. Further, although not shown in the drawings, the other rails 2 are arranged so that a cart carrying a clean saucepan can be run on them.

There is a station A at the intersection of the rails 1 and 2, and stations B and C symmetrically around the station A, and stations D, E, and F on both outsides of the stations B and C.
A stop device (not shown) is provided on the carriage side and the transfer side so that the carriages 3, 4, 5, and 6 can be stopped at each station.

A movable dissolving soil 112 equipped with an electrode 11 is provided above the station A, and a preheating top M13, 14, which is movable up and down, is provided above stations B and C, and these tops i12, 13. 14 respectively constitute a melting furnace 7.8 and a scrap bucket 9.10 so as to be closable.

Exhaust duct]~15 is connected to the above-mentioned melting furnace -J2W12.
They are separably provided and branched, and one branched part is connected to the air supply duct 16 provided at station B, and the other is connected to the air supply duct 17 provided H2i to station C, respectively. In addition, the air supply duct l [3, 17 is station B,
When the carts 3, 4, 5.6 are positioned at C, the melting furnace 7,
8. One end can communicate with the abdomen of the scrap bucket 9.10, and the other end is connected to the preheating upper M13. It is connected to a bypass duct 20 that connects both exhaust ducts 18 and 19 that communicate with +4.

Furthermore, the exhaust ducts 18, 19 merge and open to the atmosphere.

A single tube valve 21 is provided at both branches of the exhaust duct 15.
22, a stop valve 23 is provided between the connection points of the supply air ducts 1 to 1G with the exhaust duct 15 and the bypass ducts 1 to 20, and a stop valve 23 is provided between both the connection points of the supply air duct 17 with the exhaust duct 15 and the bypass duct 20. A stop valve 24 is provided in the exhaust duct 18, a stop valve 25 is provided between the bypass duct 20 of the exhaust duct 18 and the confluence point, and a stop valve 26 is provided between the bypass duct 20 of the exhaust duct 19 and the confluence point. Both ends of bypass duct 20, supply air duct 1
6. Install the stop valve 27 on both ends from the connection point 17.
．． 28 respectively.

Next, the operation of the above device will be explained.

Position the carts 3, 4, 5.6 as shown in the figure, and
．． 8 to stations A and B to scrap buckets 9.1
The melting furnaces 7 and 8 and the scrap buckets 1 to 10 are already loaded with scrap, and the scrap bucket 9 is loaded with scrap at stations C and D.

The scrap in the melting furnace 8 (station A) is melted with the stop valves 22, 23, 25, and 28 closed. The high temperature IJI gas generated during melting is removed from the station△
From there, the scrap is guided to the melting furnace 7 of station B, where it is preheated at a high temperature, and further sent from station B to the scrap bucket 10 of station C via the exhaust duct 18, bypass duct 20, and supply air dust 17. Preheat the scrap inside to low temperature.

Here, the exhaust gas fed to station B is at a high temperature and may partially melt the sedge rap, but since station B is the melting furnace 7, there is no problem. Furthermore, since the scrap whose temperature has dropped sufficiently is sent to the station C where the scrap bucket 1-10 is positioned, the scrap bucket 1-io will not be thermally damaged. Also, from station C to exhaust duct 1
The temperature of the exhaust gas exhausted from 9 is further lowered so that it can be discharged directly to the atmosphere through the bag filter (not shown) of the dust collector without any problem.

In this way, the heat of the υ1 gas generated during melting can be used for preheating the scrap.

When the melting at station A is completed, the melting upper ti1
2 is turned upside down and removed, and the melting furnace 8 is tilted to tap the molten metal into a molten metal receiving steel (not shown). Also, the upper i1. for preheating stations B and C. + and +4 are raised, the scraps in the scrap bucket 10 of station C are moved to station F, which has no lid, and the melting furnace 8 of station A is moved to station E to prepare for charging the scrap. At the same time, move carts 3, 4, 5, and 6 to the right in the figure. The sedge lap bucket [9 is moved to station B and the melting furnace 7 is moved to stage 31 A.

Stop valves 22, 23, 24°2 at the same time as the movement is completed.
6.27.28 was closed and melting started, and station B
Preheat the scraps. The work of loading scrap from scrap buckets i to 10 into the melting furnace 8 using a crane or the like, which has been carried out since before the start of operation, is quickly carried out. Move to station C, close with preheating upper M14, and close stop valve 21.

At the same time, stop valves 22, 23, 27, and 28 are opened.

Therefore, scrap bucket 9 is located at station B, melting furnace 7 is located at station Δ, and melting furnace 8 is located at station C.
, the scrap bucket 10 becomes station E.

Clay cover 12 for melting, upper i for preheating! ! At 13.14, the melting furnace 7, scrap bucket 9, and melting furnace 8 are respectively closed,
Open stop valves 22, 23, 25 and 28,
Close the tube valves 21, 24, 26, and 27 to start C dissolution. The exhaust gas from station A preheats the scrap in the melting furnace 10 of station C, which was preheated at a low temperature in the previous step, to a high temperature, and further preheats the scrap in the scrap haketo 9 of station B to a temperature IIi. Incidentally, during this melting process, the scrap bucket 10 at station E
Load the scrap into the container. When the melting is completed, the melting furnace 7 is tilted in the same manner as described above, and the low-temperature preheated scrap from the scrap bucket 1-9 of station B is charged into the now empty melting furnace 7.

Then, move the carts 3, 4, 5.6 to the left and move the melting furnace 8.
, 7. One recycle is completed by positioning the scrap buckets 1-10 to stations A, B, and C, respectively. Repeat this → noise cycle (thereby, operation continues.

In addition to the above embodiments, the melting furnace and scrap bucket may be fixed and the upper cover and duct side may be moved, and the arrangement of the ducts and the installation positions of the valves are not limited to the above embodiments.

[Effects of the Invention] As described above, according to the present invention, the following excellent effects can be exhibited.

(1) Since the preheating tank is a furnace, scrap can be preheated at extremely high temperatures, reducing the electricity consumption rate for melting.

(i) Since preheating can be done in a furnace, there is no heat damage and the equipment life is extended.

0 The scrap temperature of the melting start sowing is high, so there is less wear on the electrodes and running costs can be reduced.

(f) Energy savings can be achieved because the heat from the exhaust gas is used as residual heat until it reaches a temperature that can be released directly into the atmosphere.

(V) Equipment costs are reduced because a gas cooler is not required.

[Brief explanation of drawings]

Figures 1 and 2 are explanatory diagrams of the present invention; Figure 1 is a plan view, Figure 2 is an elevational view, Figures 3 and 4 are illustrations of the operation, and Figure 3 is an illustration of the present invention. The initial state diagram after the cart is moved, and FIG. 4 is a diagram of the normal melting and scrap preheating state diagram. 7.8 is a melting furnace, 9 and 10 are scrap buckets, 11
is an electrode, 12 is an upper lid for melting, 13; 14 is an upper lid for preheating,
21, 22, 23, 24, 25, 26, 27.28 indicate stop valves. Patent application Hitoshi Kawajima Harima Heavy Industries Co., Ltd. Patent application Hitoshi Kawajima Harima Heavy Industries Co., Ltd.

Claims (1)

[Claims] 1) 2 melting furnaces and 2 buckets are arranged symmetrically on both sides of the melting furnace, 1 melting upper lid with electrodes above the melting furnace and the buckets, and 2 melting furnaces on both sides of the upper lid. A preheating upper cover is provided, and the melting furnace, the bucket, and the third upper cover move relative to each other around the melting upper cover, so that the second melting furnace and one of the buckets are alternately closed. At the same time, a duct is provided between the upper lids of the above 3 and between the melting furnace and the buckets which are closed by the preheating upper lid, so that the exhaust gas from the furnace during melting is guided to the other melting furnace and further to the one bucket. The arc furnace equipment is characterized in that a stop valve is provided at a predetermined position of the duct so that the duct is stopped.