CN110030824A - Electric furnace - Google Patents

Abstract

The invention relates to the technical field of miniature electric furnaces for production in foundry material factories, in particular to a smelting electric furnace. The electric smelting furnace includes a furnace body (1) and a plurality of electrodes (13), a feeding port (14) is provided on the top of the furnace body (1), and an outlet (14) is provided on the side wall of the furnace body (1). A liquid port (3) and a plurality of electrode holes, the plurality of electrode holes are arranged at the same height and are located above the liquid outlet (3), and the plurality of the electrodes (13) are arranged to be able to pass through the plurality of electrodes (13) respectively The electrode holes extend obliquely downward to gather in the furnace body (1) to form a high temperature digestion zone (15), and the liquid outlet (3) is set higher than the high temperature digestion zone (15). In the electric smelting furnace, the electrodes are arranged to extend downward obliquely, so that the electric smelting furnace can increase the height difference between the electrode holes and the liquid outlet under the premise of maintaining the positional relationship between the high temperature digestion zone formed by the plurality of electrodes and the liquid outlet. The production process is optimized to ensure safe operation.

Description

Smelting electric furnace

technical field

The invention relates to the technical field of miniature electric furnaces in foundries, in particular to a smelting electric furnace.

Background technique

At present, electric arc furnaces are often used in micro-electric furnaces in foundries, which are mainly electric furnaces that use the high temperature generated by electrode arcs to smelt ores and metals. The furnace body of the existing electric furnace usually adopts a square structure, and the molten pool structure in the furnace is also set to a square shape accordingly. On the side wall, the electric furnace includes three electrodes (cylindrical structure) installed at the same height of the furnace body in the horizontal direction, named electrode A, electrode B and electrode C in turn, wherein electrode A and electrode B are inserted horizontally through the left and right side walls respectively. The furnace body is arranged at an included angle of 180°, and the electrode C is arranged along the extending direction perpendicular to the electrode A and is inserted into the furnace body horizontally through the rear side wall, so that the electrode A, the electrode B and the electrode C gather together to form a high-temperature digestion area. A liquid outlet is formed thereon, and the height of the center line of the liquid outlet is slightly lower than the height of the center lines of the three electrodes, about 5-10 cm.

However, because the difference between the center line of the liquid outlet and the center line of the electrode is 5-10 cm, that is to say, the difference between the center line of the liquid outlet and the center line of the electrode hole on the furnace body for electrode insertion is 5 cm. -10 cm, once the liquid outlet is partially blocked or completely blocked due to the viscous retention of the smelting solution, the liquid level will rise rapidly and overflow from the electrode hole, which will not only cause product loss, but also cause solution splash damage people and the possibility of burning equipment. In addition, since the electrode passes through the electrode hole in the horizontal direction, so that the high temperature digestion area is flush with the electrode hole, the liquid outlet is lower than the high temperature digestion area, and the solution flows quickly. , block the arc, cause the furnace to stop and affect the stable operation.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the problem of the high risk of smelting solution overflowing from the electrode hole caused by the too small height difference between the centerline of the liquid outlet and the centerline of the electrode hole in the miniature electric furnace of the foundry in the prior art. An electric smelting furnace, the electric smelting furnace can increase the electrode holes and the liquid outlet under the premise of maintaining the positional relationship between the high-temperature digestion zone formed by a plurality of electrodes and the liquid outlet by setting the electrodes to extend downwardly. The height difference of the mouth is safer. At the same time, a small solution pool is formed in the furnace during the smelting process, and a small amount of electrode heads are inserted into the solution to do work, which improves the stability of the working electricity load and avoids the occurrence of arc breakage during the operation of the electric furnace.

In order to achieve the above purpose, the present invention provides an electric smelting furnace, which includes a furnace body and a plurality of electrodes, the top of the furnace body is provided with a feeding port, and the side wall of the furnace body is provided with a liquid outlet and a plurality of electrode holes, the plurality of electrode holes are arranged at the same height and located above the liquid outlet, and the plurality of the electrodes are arranged to be able to pass through the plurality of the electrode holes respectively and extend obliquely downward to The furnace body gathers to form a high temperature digestion zone, and the liquid outlet is set higher than the high temperature digestion zone.

Optionally, the inclination angle between each of the electrodes and the vertical direction is set to be 50°-60°.

Optionally, the smelting electric furnace includes a plurality of electrode installation units disposed outside the furnace, each of the electrode installation units includes an electrode holder, and each of the electrode holders is supported on a position of each of the electrodes. part outside the furnace to hold each of the electrodes.

Optionally, the electrode mounting unit includes an adjuster, and the adjuster is configured to be able to adjust the position of the electrode holder, so as to adjust the inclination angle of the electrode fixed by the electrode holder with respect to the vertical direction.

Optionally, the adjuster includes an adjusting mechanism, a traveling track and a driving device, the adjusting mechanism is movably connected to the traveling track and is configured to be able to adjust the inclination angle of the traveling track relative to the vertical direction, so The electrode holder is provided on the traveling rail and can be driven by the driving device to reciprocate along the extending direction of the traveling rail.

Optionally, the adjusting mechanism includes a fixing frame and an adjusting frame, the fixing frame is arranged between the adjusting frame and the furnace body and is hinged with the traveling track, and the adjusting frame is hinged with the traveling track and set. In order to be able to drive the walking track to rotate around the hinge point between the walking track and the fixed frame.

Optionally, the side wall of the furnace body is configured as a cylindrical structure extending in the vertical direction, and the side wall of the furnace body includes three electrode holes distributed along the circumferential direction, and the smelting electric furnace includes separately arranged electrode holes. Three of the electrodes in the three of the electrode wells.

Optionally, the three electrode holes are equally spaced along the circumference of the furnace body.

Optionally, the bottom wall of the furnace body is configured as a truncated cone structure.

Optionally, the electric smelting furnace includes a pourable device, and the pourable device is rotatably connected to the furnace body, so that the pourable device drives the furnace body to rotate around a horizontal axis of rotation.

Through the above technical solutions, the present invention provides an electric smelting furnace. The electric smelting furnace is arranged to extend downwards obliquely. Compared with the installation method in which the electrodes are arranged horizontally in the prior art, it does not change the position of the plurality of electrodes. On the premise of the positional relationship (for example, height difference) between the formed high-temperature digestion zone and the liquid outlet, the height difference between the electrode hole and the liquid outlet can be increased, which is beneficial to the partial or complete blocking of the liquid outlet of the smelting furnace. The storage capacity of the smelting solution is significantly expanded, more buffer time is reserved, more solution time is provided for the staff, the risk of the smelting solution overflowing through the electrode hole is significantly reduced, it is safer, and It is conducive to the formation of a small solution pool during the smelting process, provides a convenient condition for the electrode tip to penetrate a small amount of the solution pool to perform work, improves the stability of the working electrical load, and avoids the occurrence of arc breakage during the operation of the electric furnace. At the same time, in the formed buffer small molten pool, the electrode consumes carbon and some impurities in the raw material form a reduction reaction, which is conducive to improving the quality of the product, thereby increasing the selection range of raw materials.

Description of drawings

Fig. 1 is the structural representation of the smelting electric furnace of a kind of specific embodiment provided by the present invention;

2 is a schematic structural diagram of an electric smelting furnace according to another specific embodiment provided by the present invention;

FIG. 3 is a plan view of the electric smelting furnace shown in FIG. 1 .

Description of reference numerals

1. Furnace body; 2. Support ring; 3. Liquid outlet; 4. Bearing support; 5. Small sprocket; 6. Fixed frame; 7. Adjustment frame; ; 73, fixed support panel; 74, hinged seat; 8, walking track; 9, driving device; 91, motor; 92, hydraulic cylinder; 92a, hydraulic telescopic rod; 92b, electro-hydraulic cylinder; 10, reducer; 11 11a, electrode holder walking seat; 11b, electrode holder clamping seat; 13, electrode; 14, feeding port; 15, high temperature digestion area; 37, mounting plate; 38, mounting seat.

Detailed ways

The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, but not to limit the present invention.

The present invention provides an electric smelting furnace. As shown in FIGS. 1 and 2 , the electric smelting furnace includes a furnace body 1 and a plurality of electrodes 13 . The top of the furnace body 1 is provided with a feeding port 14 . A liquid outlet 3 and a plurality of electrode holes are arranged on the side wall of the fuselage, a plurality of the electrode holes are arranged at the same height and are located above the liquid outlet 3, and a plurality of the electrodes 13 are arranged to pass through the plurality of electrodes respectively. Each of the electrode holes extends downward obliquely to form a high temperature digestion zone 15 in the furnace body 1 , and the liquid outlet 3 is set higher than the high temperature digestion zone 15 . Among them, the high temperature digestion zone refers to the area formed by the gathering of a plurality of electrodes 13 in the field of the metallurgical electric furnace, and the gathering of the plurality of electrodes 13 refers to that the ends of the plurality of electrodes located in the metallurgical electric furnace are close to each other and are concentrated but mutually No contact; the smelting electric furnace is suitable for smelting various materials such as metal materials and non-metal materials.

Through the above technical solutions, the present invention provides an electric smelting furnace. The electric smelting furnace is arranged to extend downwards obliquely. Compared with the installation method in which the electrodes are arranged horizontally in the prior art, the plurality of electrodes 13 are not changed. On the premise of the positional relationship (for example, height difference) between the formed high-temperature digestion zone and the liquid outlet, the height difference between the electrode hole and the liquid outlet can be increased, which is beneficial to the partial or complete sealing of the liquid outlet of the smelting furnace. In the case of blockage, the storage capacity of the smelting solution is significantly expanded, more buffer time is reserved, more time is provided for the staff to solve, and the risk of the smelting solution overflowing through the electrode hole is significantly reduced. It is conducive to the formation of a small solution pool in the smelting process, provides a convenient condition for the electrode tip to penetrate into the solution pool in a small amount to perform work, improves the stability of the working electrical load, and avoids the occurrence of arc breakage during the operation of the electric furnace. At the same time, in the formed buffer small molten pool, the electrode consumes carbon and some impurities in the raw material form a reduction reaction, which is conducive to improving the quality of the product, thereby increasing the selection range of raw materials.

Further, the inclination angle between each of the electrodes 13 and the vertical direction is set to be 50°-60°. Under the premise of meeting the use requirements of the electrodes, the installation stability of the electrodes 13 and the relationship between the electrode holes and the electrode holes are comprehensively considered. The height difference between the liquid outlets is more reasonable in design. As shown in FIG. 1 , the electrodes are set as round rods, each of the electrodes 13 penetrates into the furnace body 1 along an inclined downward extending direction, and the axial direction of each electrode 13 is set at an inclined angle that deviates from the vertical direction is a, the value range of the inclined angle a is set to 50°-60°, which makes the size of the electrode tip penetrating into the small solution pool more reasonable, further improves the stability of the working electrical load, and avoids the need for electric furnaces. The occurrence of arc break during operation. In order to ensure the installation stability of the electrodes, the electric smelting furnace includes a plurality of electrode installation units arranged outside the furnace body 1 , each of the electrode installation units includes an electrode holder 11 , and each of the electrode holders 11 supports The part of each of the electrodes 13 located outside the furnace body 1 is used to fix each of the electrodes 13, which also ensures that the electrodes always maintain a fixed inclination angle during the normal operation of the metallurgical electric furnace, which is beneficial to the operation of the electric furnace. Stable operation.

According to the present invention, when the electric smelting furnace smelts the material, the arc is often broken because the material entered from the top feeding port 14 is filled between multiple electrodes. For large bulk materials, the arc generated by the electrode will pass through the gaps formed between the bulk material and multiple electrodes to digest the bulk material. Although it will cause the negative charge fluctuations to drop rapidly, it will soon be possible. The large blocks are digested in the high temperature digestion zone, so that the electrodes can be restored to normal; if the materials filled between the electrodes are small blocks with too small particle size piled together, these accumulated small blocks will be different from many other materials. The electrodes are usually in close contact, and it is difficult to form voids, resulting in the arc formed by the electrodes having almost no permeability, and even causing complete arc breakage, affecting production. Considering the above problems, the materials suitable for smelting electric furnace generally need to strictly control the particle size. However, this affects the selection range of raw material particle size, causing many inconveniences during the operation of the smelting electric furnace and reducing the production efficiency. In order to expand the range of particle size selection of materials used in the smelting furnace, the electrode can be set to be able to adjust its own inclination angle. For example, the electrode mounting unit includes an adjuster configured to adjust the position of the electrode holder 11 to adjust the inclination angle of the electrode 13 fixed by the electrode holder 11 with respect to the vertical direction, In order to adjust the inclination angle of the electrode 13 reasonably according to different actual needs, and under the premise of ensuring the stable operation condition of the smelting electric furnace, the selection range of the particle size of the material is expanded, so as to maximize the effect.

Further, the adjuster includes an adjusting mechanism, a walking rail 8 and a driving device 9, the adjusting mechanism is movably connected to the walking rail 8 and is configured to be able to adjust the inclination of the walking rail 8 relative to the vertical direction angle, the electrode holder 11 is disposed on the travel track 8 and can be driven by the drive device 9 to reciprocate along the extending direction of the travel track 8, wherein the drive device 9 and the electrode holder can transmit power ground connection. When in use, the inclination angle of the walking track 8 is adjusted by the adjustment mechanism, and the walking track 8 whose inclination angle changes can drive the inclination angle of the electrode to change through the electrode holder 11 until the electrode is at the best inclination angle. At this time, the horizontal distance between the ends of the plurality of electrodes located in the electric smelting furnace is bound to change, which adversely affects the stable operation of the electric smelting furnace. The horizontal distance between the ends in the electric smelting furnace is adjusted to a reasonable range. Specifically, the electrode holder 11 can be driven to reciprocate along the extending direction of the walking track 8 through the driving device 9 to drive the electrode to follow the electrode holder. 11 Move synchronously until the ends of the electrodes located in the electric smelting furnace are in the optimal position (the optimal position means that when the horizontal distance between the ends of the plurality of electrodes located in the electric smelting furnace is adjusted to a reasonable range, each In the process of reciprocating movement of the electrode holder 11 along the walking track 8, the inclination angle of the electrode will not be affected, that is, the electrode still remains at this maximum position. optimum tilt angle. The specific structure of the electrode holder 11 is not limited. For example, the electrode holder 11 includes an electrode holder running base 11a and an electrode holder clamping base 11b which are connected to each other, and the electrode holder running base 11a is configured to be able to move along the running track. Moving and being able to be fixed on the running track 8, the electrode holder clamping base 11b is used to fix the electrode and keep the length direction of the electrode consistent with the extending direction of the running track. Wherein, the driving device 9 can be set as various reasonable devices, for example, the motor 91 shown in FIG. The connection that can transmit power; alternatively, the driving device 9 is provided as a hydraulic cylinder 92 as shown in FIG. 2 , wherein the hydraulic cylinder 92 includes a hydraulic telescopic rod 91a and an electro-hydraulic cylinder body 92b that cooperate with each other, and the electro-hydraulic cylinder body 92b is fixed On the walking track 8, the hydraulic telescopic rod 91a is connected with the electrode holder walking seat 11a of the electrode holder 11 to transmit power. On this basis, in order to facilitate the installation of the electro-hydraulic cylinder 92b, a mounting plate 37 can also be provided to install The seat 38, the mounting plate 37 is fixed on the running track, the mounting seat 38 is fixedly installed on the mounting plate 37, and the mounting seat 38 is used to fix and install the electro-hydraulic cylinder block 92b.

As shown in FIGS. 1 and 2 , the adjusting mechanism includes a fixing frame 6 and an adjusting frame 7 . The fixing frame 6 is arranged between the adjusting frame 7 and the furnace body 1 and is hinged with the walking rail 8 . The adjusting frame 7 is hinged with the walking rail 8 and is set to be able to drive the walking rail 8 to rotate around the hinge point between the walking rail 8 and the fixing frame 6 , and the walking rail 8 is driven by adjusting the height of the adjusting frame 7 . Rotate around the hinge point of the walking rail 8 and the fixing frame 6 , thereby changing the inclination angle of the walking rail 8 . According to a specific embodiment of the present invention, in order to set the inclination angle between each of the electrodes 13 and the vertical direction to be 50°-60°, as shown in FIGS. 1 and 2 , the height of the adjustment frame is always high at the height of the fixing bracket. When in use, by increasing the height of the adjusting frame, the walking track is driven to rotate clockwise around the hinge point of the walking track 8 and the fixing frame 6 in the clockwise direction as shown in FIG. The device drives the electrode and the walking track to rotate synchronously, which also increases the inclination angle of the electrode until the electrode rotates to the optimal inclination angle. The inclination angle of the electrode remains the same; at this time, the end of the electrode located in the smelting electric furnace moves down, and the horizontal distance from the ends of the other electrodes located in the smelting electric furnace increases. In order to make the smelting electric furnace run stably, Start the driving device, and drive the electrode holder 11 to move toward the furnace body along the extending direction of the walking track 8 through the driving device, so as to drive the electrode to move synchronously with the electrode holder 11, until the electrode moves again until the electrode is at The position just below the position before the rotation is to shorten the horizontal distance between the electrode and the other electrodes. Keep a reasonable horizontal distance between the ends in the smelting furnace. The adjusting frame 7 can be set to various reasonable structures. For example, the adjusting frame 7 includes a sprocket adjusting rod 71, a movable support plate 72, a fixed support panel 73 and a hinge seat 74 as shown in FIG. The bottom end of the pull rod 71 is hinged with the fixed support panel 73, the top end of the pull rod 71 is movably connected with the middle of the movable support plate 72, and the bottom end of the movable support plate 72 is hinged with the fixed support panel 73 through the hinge seat 74, and the movable support plate 72 is hinged with the fixed support panel 73. The top end of the support plate 72 is movably connected to the running track. When in use, the specific operation steps for adjusting the inclination angle of the walking track to increase are as follows: first rotate the flower-turn adjusting rod 71 around the hinge of the flower-turn adjusting pull rod 71 and the fixed support panel 73 in a clockwise direction as shown in FIG. The adjustable pull rod 71 moves upward along the extending direction of the movable support plate 72. At this time, the adjustable movable support plate 72 rotates in a clockwise direction around the hinge between the movable support plate 72 and the fixed support plate 73 as shown in FIG. 2 . , then the inclination angle of the walking track increases until the inclination angle of the rotating track increases to the optimum angle, move the flower pull adjustment rod 71 up to the appropriate position of the movable support plate 72 and fix it, and move the movable support plate 72 down To a suitable position of the walking track and fix it; of course, the specific operation of adjusting the inclination angle of the walking track to reduce can refer to the above operation, and will not be repeated.

As shown in Figures 1 and 2, the side wall of the furnace body 1 is configured as a cylindrical structure extending in the vertical direction, and the side wall of the furnace body 1 includes three electrode holes distributed along the circumferential direction, so The smelting electric furnace includes three electrodes 13 respectively arranged in the three electrode holes. By setting the furnace body as a cylindrical structure (that is, the furnace shape is set as a circle), the rationality of the furnace body structure is optimized. , thereby increasing the service life of the furnace body.

As shown in FIGS. 1-3 , the three electrode holes are equally spaced along the circumference of the furnace body 1 . As shown in FIG. 3 , the three electrode holes are on the same cross section of the furnace body 1 , and on this cross section, the central angle corresponding to the arc between the centers of any two of the electrode holes is 120° , so that the electrode distribution is more uniform, the heat energy distribution in the melting zone in the electric furnace is more uniform, and the service life of the smelting electric furnace is increased. Further, as shown in Figures 1 and 2, each electrode passes through the corresponding electrode hole and extends downward along the slope as shown in Figure 1 to enter the furnace body 1, and the electrodes are arranged to extend downward at a slope. , which is beneficial to increase the height difference between the electrode hole and the liquid outlet, so that the smelting furnace can significantly expand the storage capacity of the smelting solution when the liquid outlet is partially or completely blocked, leaving more buffer time, significantly It reduces the risk of the smelting solution overflowing through the electrode hole, and has high safety. It can also form a small solution pool during the smelting process, which provides a convenient condition for the electrode tip to penetrate into the solution pool in a small amount to perform work, and improves the working power load. Stability, avoiding the occurrence of arc break during the operation of the electric furnace.

Further, the bottom wall of the furnace body 1 is configured as a truncated cone structure, which has a simple structure and saves floor space.

Further, the smelting electric furnace includes a pourable device, and the pourable device is rotatably connected with the furnace body 1, so that the pourable device drives the furnace body 1 to rotate around a horizontal axis of rotation, It is beneficial to deal with the remaining materials in the smelting electric furnace, which is convenient and quick, reduces labor intensity, saves energy and reduces consumption. Specifically, the pourable device can be set to various reasonable structures. For example, the pourable device includes a motor, a support ring 2 , a bearing support 4 and a small sprocket 5 , wherein the output shaft of the motor passes through the conveyor belt and the small sprocket 5 . Connected in a power-transmitting manner, the output shaft on the small sprocket 5 passes through the bearing hole on the bearing support 4 and is connected with the supporting ring in a power-transmitting manner, and the supporting ring 2 is sleeved outside the bottom wall of the furnace body in a truncated cone structure. . When in use, the small sprocket is driven to rotate synchronously by the motor, so as to drive the support ring 2 to rotate around the axis of the output shaft of the small sprocket through the output shaft of the small sprocket, and then drive the furnace body to rotate synchronously with the support ring 2, thereby It is achieved that the furnace body can be automatically tipped, wherein the axis of the output shaft of the pinion gear is arranged to extend in the horizontal direction.

The preferred embodiments of the present invention have been described above in detail with reference to the accompanying drawings, however, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, a variety of simple modifications can be made to the technical solutions of the present invention. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations. However, these simple modifications and combinations should also be regarded as the contents disclosed in the present invention, and all belong to the protection scope of the present invention.

Claims (10)

1. a kind of electric furnace, which is characterized in that the electric furnace includes furnace body (1) and multiple electrodes (13), the furnace It is provided at the top of body (1) feeding inlet (14), liquid outlet (3) and multiple electrodes hole is provided on the side wall of the furnace body (1), it is more In sustained height and positioned at the top of the liquid outlet (3), multiple electrodes (13) are set as a electrode hole setting Multiple electrode holes can be each passed through and extended obliquely downward to collect to form thermophilic digestion area in the furnace body (1) (15), the liquid outlet (3) is set above the thermophilic digestion area (15).

2. electric furnace according to claim 1, which is characterized in that between each electrode (13) and vertical direction Slanted angle is set as 50 ° -60 °.

3. electric furnace according to claim 2, which is characterized in that the electric furnace includes being arranged in the furnace body (1) multiple electrodes installation unit outside, each electrode installation unit include electrode holde (11), each electrode handle Holder (11) be supported on each electrode (13) be located at the part of the furnace body (1) outside with each electrode of fixation (13)。

4. electric furnace according to claim 3, which is characterized in that the electrode installation unit includes adjuster, described Adjuster is configured to adjust the position of the electrode holde (11), is fixed with to adjust the electrode holde (11) Tilt angle of the electrode (13) relative to vertical direction.

5. electric furnace according to claim 4, which is characterized in that the adjuster includes regulating mechanism, walking track (8) it is movably connected in the walking track (8) with driving device (9), the regulating mechanism and is configured to adjust Tilt angle of walking track (8) relative to vertical direction, the electrode holde (11) are arranged in the walking track (8) extending direction along walking track (8) can be driven to move back and forth on and by the driving device (9).

6. electric furnace according to claim 5, which is characterized in that the regulating mechanism includes fixed frame (6) and adjusts Frame (7), the fixed frame (6) are arranged between the adjusting bracket (7) and furnace body (1) and with the walking track (8) hingedly, The adjusting bracket (7) is hinged with the walking track (8) and is configured to drive the walking track (8) around the walking Track (8) and the hinge joint of fixed frame (6) rotate.

7. electric furnace described in any one of -6 according to claim 1, which is characterized in that the side wall of the furnace body (1) is set It is set to the cylindrical structure extended along the vertical direction, and includes three circumferentially distributed electrodes on the side wall of the furnace body (1) Hole, the electric furnace include three electrodes (13) being separately positioned in three electrode holes.

8. electric furnace according to claim 7, which is characterized in that week of three electrode holes along the furnace body (1) To being equally spaced.

9. electric furnace according to claim 1, which is characterized in that the bottom wall of the furnace body (1) is set as frustum of a cone knot Structure.

10. electric furnace described in any one of -9 according to claim 1, which is characterized in that the electric furnace includes can Tilting device, the dumpable device are rotatably attached with the furnace body (1), so that described in the dumpable device drive Furnace body (1) is rotated around the rotation axis of horizontal direction.