JPH0584040B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to the improvement of an electrode joint device for an electric furnace using consumable electrodes, and relates to the improvement of an electrode joint device for an electric furnace that uses a consumable electrode. This allows work to be performed without mechanically supporting the force, and is intended to make the device smaller and lighter.

[Conventional technology]

In electric furnaces such as arc furnaces, electrodes are essential, and graphite electrodes are generally used. This graphite electrode gradually wears out as operations are repeated, so it is common practice to add another electrode when it becomes short to a certain extent, which eliminates wasted electrodes and reduces steel manufacturing costs.

This kind of electrode fitting work must be done in a high-temperature working environment on an electric furnace.Moreover, as electric furnaces become larger and more powerful, the electrodes become larger, making it difficult to tighten them during input work. However, since the tightening torque varies and it is easy to break, an electrode joint device is used.

For example, as shown in FIG. 2, a factory crane 2 that is normally installed for loading raw materials into the electric furnace 1 or for maintenance of the electric furnace 1 can be used as is.
There is a portable electrode joint device 3 that is suspended from the factory crane 2 and used.

That is, rails are laid on a pair of left and right beams near the ceiling of a steel factory, a pair of crane girders 5 equipped with a traveling device and connected at both ends by saddles 4 are mounted on the rails, and a pair of crane girders 5 are placed on the rails, and A crane 2 is equipped with a trolley 7 equipped with a traversing device on a rail 6 laid on a crane girder 5, and a hook 9 is suspended from a winding device installed on the trolley 7 via a cable 8. , the support frame 10 of the electrode joint device 3 is suspended, and the joint electrode 13 is supported via a nipple 12 at the tip of a hydraulic motor 11 that constitutes a rotation mechanism attached to the support frame 10. .

When adding the additional leg electrode 13 to the above-furnace electrode 1a of the electric furnace 1, the position of the crane girder 5 of the crane 2 and the position of the trolley 7 are
A, 13 are positioned on the same axis, the hook 9 is lowered by the winding device, and the hydraulic motor 11 is turned on when the nipple 12a at the lower end of the extension electrode 13 faces the screw hole at the upper end of the furnace electrode 1a. Rotate and screw in the additional leg electrode 13 to add more.

Such a portable electrode connecting device 3 can use an existing factory crane 2, so it is cheaper than installing a dedicated electrode connecting device. Since it is only lowered, it is unable to support the reaction force generated by the hydraulic motor 11 when screwing in, making it impossible to screw in the additional leg electrode 13, and making it impossible to remove the nipple 12 after adding more. .

Therefore, by using a pair of crane girders 5 connected by the saddles 4 of the factory crane 2, the length of the saddles 4, that is, the distance between the crane girders 5 (wheelbase) is The arms 14 corresponding to the crane are fixed by protruding from both sides, and the supporting hardware 15 attached to the upper surface of the tip of these arms 14 is pressed against the lower surface of the crane girder 5 by hoisting the crane to support rotational reaction force. There is.

However, the crane 2 of the factory where the electric furnace 1 is installed is used for the purpose of transporting steelmaking materials, etc.
It is a large ton-class device, and the spacing between the crane girders 5 is very wide at 4 m or more, and the arm 14 protrudes largely from the support frame 10 of the electrode leg device 3, making the electrode leg device 3 extremely large. I end up.

In addition, when performing joint work, it is necessary to press the support hardware 15 against the crane girder 5 to support the rotational reaction force, but if the crane is hoisted too much, the arm 14 may be deformed or damaged.
On the other hand, if the winding is insufficient, the rotational reaction force cannot be completely supported, and it takes a long time to adjust the height of the electrode connecting leg device 3 so that it can support the reaction force.

[Problem that the invention seeks to solve]

The present invention has been made in view of the above-mentioned prior art, and aims to provide a compact and lightweight electric furnace electrode foot device that does not require special work to support rotational reaction force even if it is portable using an existing crane. This is the purpose.

[Means for solving problems]

In order to achieve this object, the present invention provides a rotary feed mechanism that rotates and feeds the connecting leg electrode in order to screw it into the furnace electrode on a support frame suspended from a crane installed above the electric furnace. A drive source equipped with a flywheel that drives the rotary feed mechanism is provided, and a disconnecting means is provided between the drive source and the rotary feed mechanism to disconnect and disconnect the transmission of driving force to enable inertial rotation. It is characterized by:

[Effect]

This is a portable electrode connecting device that is used by hanging from a crane, and the rotating feed mechanism for screwing in the connecting electrode is driven by a drive source equipped with a flywheel via a clutch or other disconnecting means. When screwing in the extra leg electrode, it is screwed in using the inertial force between the extra leg electrode and the flywheel or the inertia of the extra leg electrode alone, while the electrode attachment device and the screwed in extra leg electrode are screwed together. When it is removed, it is removed using the usual force of the flywheel, making it possible to perform joint work without special rotational reaction force support, thereby reducing the size and weight of the device.

〔Example〕

An embodiment of the present invention will be described in detail below with reference to the drawings.

As shown in FIG. 1, which shows the longitudinal cross-sectional structure of the electrode joint device 20 for an electric furnace, the support frame 2 has a substantially cylindrical shape and has a flange portion 21a formed at its upper end.
1, and is adapted to be hung by being hung from a hook 9 of a factory crane by a hanging fitting 22 to which a flange portion 21a is attached.

A spline shaft 23 is disposed at the center of the support frame 21, and its intermediate portion is supported via a bearing 24 so as to be rotatable. A screw shaft 25 is provided on the outer periphery of the spline shaft 23 and has a female spline formed at the upper end to be fitted with the splines of the spline shaft 23.
3 and can slide vertically.

On the outer periphery of this screw shaft 25, a male thread of the same pitch as the nipple 29 etc. for connecting the additional leg electrode 13 is formed, and the support frame 2
1, and when the spline shaft 23 is rotated, the screw shaft 25 is rotated and feed is applied.

This screw shaft 25 is attached to the spline shaft 23.
A sliding bearing 27 is provided at the lower end of the spline shaft 23 in order to keep the screw shaft 25 coaxial with the screw shaft 25, so that the inner circumferential surface of the screw shaft 25 can rotate and slide. Further, a mounting plate 30 to which a nipple 29 is attached is connected to the lower end surface of the screw shaft 25 via two universal joints 28, and the additional leg electrode 13 is attached to the nipple 29.

Next, the spline shaft 23, the screw shaft 2
5. The drive source that drives the rotational feed mechanism composed of the feed nut 26 and the like will be explained.

A hydraulic motor 32 equipped with a reducer 31 is installed at the upper end of the support frame 21, and its output shaft 3
A flywheel 34 is attached to 3 via a key to constitute a drive source, and the output shaft 33 and the spline shaft 23 are arranged coaxially.

A clutch 35 is interposed between the output shaft 33 and the spline shaft 23 as a means for connecting and disconnecting the transmission of driving force, and can be operated by an operating mechanism (not shown). As this clutch 35, for example, a wet type multi-plate clutch, a dry type single plate clutch, or an electromagnetic clutch is appropriately selected and used.

Further, on the support frame 21, a hydraulic motor 3 is mounted.
A control unit 36 for controlling the clutch 2 and the clutch 35 is installed, and can be remotely controlled by a pendant switch (not shown) or the like.

Next, an explanation will be given of the electromagnetic connecting operation and the operation of each part using the electrode connecting device 20 configured as described above.

First, the electrode connecting leg device 20 is suspended by hanging the hanging fitting 22 on the upper part of the support frame 21 from the hook 9 of a factory crane.

Then, operate the crane to remove the additional leg electrode 13.
In order to attach the connecting electrode 13 to the nipple 29 of the mounting plate 30 provided at the lower end of the electrode connecting device 20, the hydraulic motor is Rotate and install 32.

After attaching the extra leg electrode 13 to the nipple 29 of the mounting plate 30 in this way, prepare for the extra leg work.
Clutch 35 is engaged and hydraulic motor 32 is reversed to place screw shaft 25 in the uppermost position.

After this, operate the crane and use the additional leg electrode 1.
3 is positioned so that it is approximately coaxial with the furnace electrode to be added, and the hook 9 is lowered to a predetermined height.

Next, when the clutch 35 is engaged and the hydraulic motor 32 is rotated, the flywheel 34 is rotated and the spline shaft 23 is also rotated.
The screw shaft 25 fitted therewith is rotated. Therefore, the screw shaft 25 and the connecting leg electrode 13 are advanced by the feed nut 26 with the same screw pitch as the nipple.

Then, just before the nipple at the lower end of the extension electrode 13 faces the screw hole at the upper end of the furnace electrode, the clutch 3 is turned off.
Open 5. Then, the electrode for the extra leg 1
Due to the inertial force due to the rotating mass of
is rotated as it is and screwed into the furnace electrode.

In this way, screwing is performed using inertia force, so no rotational reaction force is generated, and the moment screwing is completed,
The electrode connecting leg device 20 is small (about a few degrees)
It's just not twisted.

In this device, the inertial force of the flywheel 34 is not used when screwing in, but a clutch is also interposed between the output shaft 33 and the flywheel 34, and only this clutch is released after rotation. Then, the inertial force of the flywheel 34 can also be used for screwing, which is effective for connecting small electrodes.

Next, in order to disconnect the nipple 29 of the mounting plate 30 and the extra leg electrode 13, the clamp is replaced with a new electrode (extra leg electrode 13) with an electrode holder added, and the new electrode is held in place. .

Thereafter, with the clutch 35 released, the hydraulic motor 32 is started, and the flywheel 34 is rotated in a direction to loosen the nipple 29.
After reaching a certain rotational speed, the clutch 35 is engaged, the spline shaft 23 and the screw shaft 25 are rotated by the inertia of the flywheel 34, and the nipple 29 is removed.

Even in this case, if a clutch is interposed between the output shaft 33 of the hydraulic motor 32 and the flywheel 34, it will not matter whether the hydraulic motor 32 is rotating or stopped or whether a worm gear or the like is used as the reducer 31. The inertial force of the flywheel 34 can be used for this purpose.

In this way, the connection between the nipple 29 and the connecting leg electrode 13 is removed by inertial force, so no large rotational reaction force is generated, and the electrode connecting leg device 20 is only slightly twisted as in the case of screwing.

After the extension work is thus completed, the electrode extension device 20 is moved and the electrode holder is operated on the electric furnace to adjust the electrode protrusion length.

Note that if there are a large number of furnace electrodes, the above-mentioned operation may be repeated to perform the additional operation.

Further, the drive source is not limited to a hydraulic motor, but an electric motor or other fluid pressure motor may be used.

〔Effect of the invention〕

As specifically explained above in conjunction with the embodiments, according to the present invention, there is provided a portable electromagnetic connecting leg device that is used by being suspended from a crane, and a rotary feed mechanism for screwing in the connecting leg electrode is provided with a flywheel. Since the drive source is connected to the drive source via the connecting/disconnecting means, the inertia force can be used when screwing in or removing the connecting leg electrode by operating the connecting/disconnecting means, and rotational reaction force can be used. No special support is required.

Therefore, the device can be made smaller and lighter than before, and there is no work to support the rotational reaction force during the joint work, and the work can be done in a short time.

Furthermore, since the device is small and lightweight, it is easy to move and transport, and the storage space for the device is also small.

Furthermore, with conventional devices that support rotational reaction force by pressing an arm against the crane, consideration must be given to comply with safety-related laws and regulations, and reinforcement of the crane, etc. is required, but such consideration is not necessary. It has a simple structure and is inexpensive.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of an embodiment of an electrode connecting device for an electric furnace according to the present invention, and FIG. 2 is a front view of a conventional device. DESCRIPTION OF SYMBOLS 1... Electric furnace, 1a... Furnace electrode, 2... Factory crane, 9... Hook, 13... Extension electrode, 20... Electrode extension device, 21... Support frame, 23... Spline shaft, 25... Screw shaft, 26... Feed nut, 29...Nipple, 30...Mounting plate, 32...Hydraulic motor, 33...Output shaft, 34...Flywheel,
35...Clutch.

Claims (1)

[Claims] 1. A support frame suspended from a crane installed above the electric furnace is provided with a rotary feed mechanism that provides rotation and feed in order to screw the connecting electrode into the furnace electrode, and a flywheel is provided to drive this rotary feed mechanism. While providing a drive source with
An electrode joint device for an electric furnace, characterized in that a connecting/disconnecting means is interposed between the drive source and the rotational feed mechanism to disconnect/disconnect transmission of driving force to enable inertial rotation.