JPH024194A - Control of slag removing device for arc furnace - Google Patents

Abstract

PURPOSE:To avoid the collision of working tools, inserted into an arc furnace, against both side surfaces of the working port of the arc furnace and permit works for removing slag and the like easily by determining a vertical line near the working port of the arc furnace and restricting the working tools so as to be intersected with the vertical line. CONSTITUTION:A rotatable rotary base board 17 is provided on a running carriage 2 through a necessary rotating mechanism 4. An operating room 7 is mounted on the rotary base board 17 while the rotary base board 17, steering a slag removing device 100, is provided with an upper stage stretchable boom 5 attached stretchably and the upper stage stretchable boom 5 is provided with a lower stage stretchable boom 18 attached stretchably thereto. The lower stage stretchable boom 18 is provided with an arm supporting frame 6, attached derrickably through a necessary derricking mechanism 19 having an axle 20 or a rotary center. Working tools 8 are attached replaceably to the arm supporting frame 6. The arc furnace 11 may be slanted by an annexed linear actuator, in which a fixed arced rack 21 having a radius R is engaged with the arced rack 22, provided on the lower surface of the arc furnace and provided with a radius (r) (R=2r).

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a method for removing slag floating on the surface of molten metal, stirring the molten metal, or performing other incidental operations during steel refining in an arc furnace. The present invention relates to a method for controlling a slag removal device.

[Prior Art 1] Slag removal, stirring, and other incidental operations in an arc furnace are hard labor under flaming heat and involve danger. Therefore, machines have been developed to perform these operations, but when such a sludge removal device is used, a problem arises in that a working tool inserted into the arc furnace collides with the arc furnace working opening.

As a conventional slag removing device that attempts to avoid collision between a working tool and a working opening, there is a device disclosed in Japanese Patent Publication No. 62-8713, for example, as shown in FIG. After the front slide block 94 is set to be positioned directly above, sludge removal is performed by advancing and retracting the advance/retreat beam 95 and adjusting the elevation angle of the scraping rod 96. The direction is set by rotating the front slide block 94. The reciprocating beam 95 functions to keep the slag discharge point at the hot metal orifice 91 fixed directly below.

[Problems to be Solved by the Invention] As is clear from FIG. 9, the conventional slag removal device described above has the following problems:
Since the upper part of the hot metal spout 91 is sandwiched between the advancing and retracting beam 95 and the scraping port 7 door 96, there is a problem that this slag removal device cannot be used when there is not enough free space above the hot metal spout 91.

In addition, the front slide block 94, which is the center of rotation of the scraping rod 96, is positioned directly above the hot metal opening 91.
It requires considerable skill and time because it relies on the visual operation of the worker, and when the front slide block 94 is in a position shifted from directly above the hot metal opening 91, the tobeed car 90
There was a problem in that the slag 93 deep inside the left and right sides could not be sufficiently scraped out.

The present inventor has conducted extensive research to solve the above problems, and has developed a sludge removal device for an arc furnace, and has also come to invent a method for controlling the sludge removal device for an arc furnace according to the present invention. That is, the present invention provides a control method for an arc furnace sludge removal device that allows operations such as sludge removal to be easily performed by avoiding collision between a work tool inserted into an arc furnace and both sides of an arc furnace working opening. [Means for Solving the Problems 1] The present invention defines a perpendicular line near the working opening of an arc furnace.

The above object is achieved by restraining and controlling the working tool so that it intersects the perpendicular line.

That is, the present invention comprises: a cart disposed facing the working opening of the arc furnace trunk and movable left and right; and a working tool mounted on the cart via a rotating mechanism, a telescoping mechanism, and an elevating mechanism. ,
A control method for an arc furnace slag removal device comprising a control device for controlling each of the travel, rotation, expansion/contraction, and four-down mechanisms, wherein the specifications of the arc furnace, the tilting mechanism, and the tilting angle are changed to a stationary state by coordinate transformation. a step of determining the position of the working opening after tilting with respect to the coordinate system; and a step of determining the position of the work tool on the horizontal plane with respect to the stationary coordinate system by coordinate transformation from the specifications of the sludge removing device and the current positions of the traveling and turning mechanisms. a step of determining a perpendicular line near the work opening after the tilting, and a step of determining a target position of the work tool under constraint conditions that intersect the perpendicular line and position the work tool. A method for controlling a sludge removal device for an arc furnace, comprising the steps of: performing inverse coordinate transformation on the target position to determine operating amounts for each of the traveling and turning mechanisms.

Here, regarding the process of determining a perpendicular line near the work opening after tilting, first, obtain a vertical cross section of the work opening in the front and back direction after tilting, obtain a horizontal line that cuts the vertical cross section at a horizontal plane of a constant height, The intersection between the horizontal line and the inner and outer wall surfaces of the work opening can be internally or externally divided, and can be determined as a perpendicular line passing through the internal or external dividing point, and in this case, the certain height can be set as It can also be automatically input as the current height of the bottom of the tip.

Second, find the vertical cross-section of the working opening in the front-rear direction when the arc furnace is in a horizontal position, and find the point at which a point at a certain height on the line of intersection between the vertical cross-section and the inner wall surface of the working opening moves after the arc furnace is tilted. Determine by coordinate transformation, divide the illumination point and the intersection of the horizontal line passing through the illumination point and the outer wall surface of the work opening after tilting internally or externally, and define it as a perpendicular line passing through the internal or external dividing point. In this case, the fixed height can also be automatically input as the height of the lower tip of the power tool when the arc furnace is in a horizontal position.

Thirdly, it can be automatically determined as a perpendicular line passing through the current position of the lower tip of the power tool.

Fourth, find the position of the lower tip of the working tool when the arc furnace is in a horizontal position, find the point where the lower tip moves after tilting the arc furnace by coordinate transformation, and define it as a perpendicular line passing through the illumination point. I can do it.

[Example 1] First, an example of an arc furnace slag removal device to which the control method according to the present invention is applied will be explained based on the drawings. FIGS. 1 and 2 are a side view and a plan view, respectively, of an arc furnace and a sludge removal device, and the arc furnace is a cross-sectional view. In the figure, the schematic structure of the sludge removing device lOO is as follows. 7 2 is a running trolley configured to run freely by a running mechanism (not shown) with running wheels 10 running on rails 3 laid on the floor l. The traveling carriage 2 is provided with a turning base 17 which can turn freely via a necessary turning mechanism 4. That swivel base! 1
A driver's cab 7 is mounted on the vehicle 7, and an operation panel (not shown) is attached thereto to operate the sludge removal device 100. The pivot base fi
17 is provided with an upper telescopic frame 5 which is mounted on the upper telescopic frame 5 so as to be extendable and retractable via a required telescopic mechanism (not shown). A lower extendable frame 18 is provided which is freely attached, and an arm support frame 6 is attached to the lower extendable frame 18 so as to be able to move up and down via a required elevating device t119 about a pivot shaft 20 as a rotation center. The arm support frame 6
A working tool 8 for performing slag removal, stirring, and other incidental operations is replaceably attached to the .

As mentioned above, in this slag removal device, the elevating mechanism is the elevating mechanism 1.
9, each of the traveling, turning, and extending/contracting mechanisms is driven by a hydraulic servo motor, and the elevating mechanism is driven by a hydraulic servo cylinder. Further, the position of each mechanism is detected by output from a resolver integrated with a hydraulic servo motor or a hydraulic servo cylinder.

On the other hand, as shown in FIG. 8, in the arc furnace 11, an arcuate rack 22 with a radius r (R=2r in this example) on the lower surface of the arc furnace is engaged with a fixed arcuate rack 21 with a radius R, and an attached linear actuator (not shown). This tilting causes the arc furnace to roll on a fixed arc rack. In other words, the position and angle of the working opening 15 change.

The general operation of the slag removal device 100 is as follows. 1. For example, when performing slag removal work, the work tool 8 is inserted into the furnace through the inclined work opening 15 of the arc furnace 11, and the work tool 8 is operated by the traveling mechanism and the turning mechanism 4. The direction of the tool 8 is determined, and the lower end 9 of the working tool 8 is operated by the telescoping action by the telescoping mechanism and the lifting action by the elevating mechanism 6, and the slag 13 floating on the surface 14 of the molten metal 12 is removed from the furnace through the work opening 15. Scrape it out. During stirring work, the direction of the working tool 8 is determined by the traveling mechanism and the turning mechanism 4, the lower tip 9 of the working tool 8 is pushed into the molten metal 12 by the elevation IIN side 6, and the lower tip 9 of the working tool 8 is moved by the telescoping mechanism. is operated to stir the molten metal 12. When changing the sludge removal location or stirring location, run and rotate.

It is unnecessary to explain that it is controlled by all operations of the extension/contraction and elevation mechanisms.

FIG. 3 is a diagram showing an example of the hardware configuration for controlling the slag removal device 100, including an instruction device 69, a joystick 7,
4. Inputs from the select switch 70, push button 71, resolver 68, etc. are sent to the main control processor 50, servo control processor 52. A/D conversion board 53. [10 board 57, calculation board 54.62, D/A conversion board 5
9. Processed by parallel board 60 etc. and displayed on display device 6
6, handed over to a servo motor 67, etc.

Next, each step of the control method according to the present invention will be explained. The present invention restrains and controls the work tool so that it intersects a perpendicular line defined near the work opening, thereby preventing collision between the work tool and both sides of the work opening. Therefore, this restraint control has nothing to do with the expansion/contraction mechanism and the lifting/lowering mechanism.In other words, even if the work tool expands and contracts, the positional relationship between the work tool and the work opening does not change, and the tip of the work tool and the arc (Collision with the furnace inner wall will be solved by another invention).Also, since the amount of lifting and lowering of the working tool is limited in the work performed by the slag removal device, the collision between the working tool and the upper and lower surfaces of the working opening is limited. Collisions do not need to be considered. That is, the present invention is not intended to avoid collisions between the working tool and the upper and lower surfaces of the working opening.

However, as a sludge removing device, in addition to restraining and controlling the horizontal direction of the work tool, it is generally necessary to operate the telescopic FR side, RFL, and lowering mechanism, as described in the general operation of the sludge removing device. Therefore, in the following embodiment, a case will be described in which all the mechanisms of traveling, turning, extension/contraction, and lifting/lowering are controlled.

However, it is clear that the expansion/contraction and lifting mechanisms are not directly related to the present invention, and therefore in the following explanation, if either or both of the expansion/contraction and lifting mechanisms are not operated,
This may be another embodiment of the invention.

First, based on the explanatory perspective view of FIG. 4, the process of determining the position of the work opening after tilting with respect to the stationary coordinate system by coordinate transformation from the specifications of the arc furnace, the tilting mechanism, and the tilting angle will be explained. This process is generally performed to the first order by simultaneous transformations.

First, a rectangular coordinate system GA- is determined. However, i = 0 is a stationary coordinate system whose origin is the top of the rail, the front of the arc furnace, and the center line of the rail gauge, i - 1 is a coordinate system fixed on the center axis of the fixed arc rack, and i = 2 is the arc When the furnace tilting angle is 0 degrees, the coordinate system is fixed on the central axis of the arc furnace tilting rack, i=3 is GA2 after the arc furnace has rolled, and i=4 is the coordinate system at the conversion target position.

Next, let the rotation angle of the i-th coordinate system (the counterclockwise direction is positive when viewed from the positive direction of the rotation axis) be θ.

θ3 is the arc furnace rolling angle. Also, the position vector PaI of GAI (origin) expressed in the (i-1) coordinate system is P i
l, = (ao, bo, co) = (0, bo, co)
P a2= (at, bt, C+)= (0,0
,R+r)Pil,-(A2.b2.c2)=(0
,1)2. C2) P a4= (as, bq, cq).

Next, the A matrix representing the relationship between the i-th coordinate system and the (i+1)-th coordinate system is A + = T trans (a,), bo, co) A2
=Trans(al, bt, c+) A I = T
rans(ag, b2.c2) Rot(X3.θ3)
A4 = T trans(al, b3.cq), and the T matrix representing the position and orientation of an arbitrary location GA4 on the arc furnace viewed from the stationary coordinate GAo is A + A2 Aq
Since A4, the T matrix can be found from the condition that the lower surface of the arc furnace and the fixed arc rack are engaged and R=2r. In this example, Px=aq+a, I Py=blcosθ1-c-4sinθq-3r
sin(θJ3))b.

Pz=blsinθ1+clcosθq+3rcos(
θq/3)+c(1, therefore, if the arc furnace transfer angle θ3 is given, the position of any location on the arc furnace (for example, the work opening 15) can be recognized in the reference coordinate system. That is, in this implementation In the example, the square of the working opening (point p in FIG.
,,p2. If the locations of p3 and P4) are set and saved in advance in the control device and the target furnace is specified, it is possible to correspond to a plurality of arc furnaces. Further, the arc furnace transfer angle θ1 is input manually from the control panel or directly from the arc furnace transfer angle detector.

Next, a process of determining the direction of the work tool on the horizontal plane with respect to the stationary coordinate system using the seat ring transformation from the specifications of the sludge removing device and the current positions of the traveling and rotating mechanisms will be described. In this embodiment, since the position and orientation of the lower tip 9 of the power tool 8 is managed, this process is performed as described above, such as traveling, turning,
Depending on the current position of all the telescoping and elevating mechanisms, this is generally done as follows.

That is, as shown in the explanatory diagram of FIG. 5, the orthogonal coordinate system GJ
Define I. However, i=0 is the reference stationary coordinate system, i=
1 is the coordinate system defined on the rotation axis and the elevation axis height, i = 2
is the coordinate system defined at the center of the work tool at the height of the vertical axis and the position perpendicular to it and intersects with the rotation axis, i = 3 is the coordinate system determined on the vertical axis, and i = 4 is determined at the work tool mounting surface. In the coordinate system, i=5 is the coordinate system determined at the lower part 9 of the tip of the working tool and is the position to be converted.

Thereafter, the T matrix can be obtained in the same manner as above, and in addition to the specifications of the sludge removing device, the joint variables xo (travel axis travel ff1), y2 (extension amount of telescopic axis), and θ1 (rotation angle of rotation axis) and θ-4 (rotation angle of the lifting axis), the position and orientation of the lower tip 9 of the working tool can be managed in the reference coordinate system, and the direction of the working tool 8 on the horizontal plane can also be recognized. I can do it. That is, by performing coordinate transformation using the current values input from the resolver as joint variables in the order shown in FIG. 7, the current position is obtained as the starting point Ps.

Next, a perpendicular line 32 (Fig. 8) is placed near the work opening after tilting the arc furnace.
Establish. Here, this perpendicular line is the perpendicular line and the work tool 8.
Since the direction of the work tool 8 is restricted so that the perpendicular lines thereof intersect with each other, that is, the perpendicular line thereof is included in the vertical plane of the longitudinal section of the work tool 8, the work opening 15 as shown in FIG.
It is preferable to set the distance between the inner wall surface 30 and the outer wall surface 31 to [mA, but it is preferable that
It can also be set slightly outside C. In other words, in this specification, "J defining a perpendicular line near the working opening" refers to the distance A between the inner wall surface 30 and the outer wall surface 31 of the working opening, or the distance B slightly inside the inner wall surface 30, or the distance C slightly outside the outer wall surface 31.
It means to set a perpendicular line to .

Furthermore, in this embodiment, the perpendicular line 32 is determined not by determining the x, y coordinates in the stationary coordinate system (but by determining the x, y, z coordinates, and by determining the target position of the work tool in the next step) In the process, two coordinates are ignored.The point defined by the x, y, and z coordinates is called a constraint point Pc.

Next, the process of determining the target position of the working tool 8 under the constraint that the working tool 8 is positioned intersecting the perpendicular line 32 will be described with reference to FIG.

In the case of manual operation, the position increment amount δX, δy of the lower part 9 of the tip of the power tool corresponds to the speed in the x, y, and z directions instructed by the operator using the tilt angle of the joystick 74 attached to the operator's cab operation panel.
, δ2, and in the case of automatic, the position increment of the lower part 9 of the tip of the work tool is determined from the position of the teaching data stored in the main controller and the command speed, and the current value of the lower part 9 of the tip of the work tool that has already been determined is By adding the position increment amount to the position (starting point) Ps, the target position data of the lower part 9 of the tip of the power tool is determined. Next, from the target position data and the position of the constraint point Pc, a target turning angle of the power tool 8 is determined, ignoring the two coordinates, and 0 black attitude data is created from this target turning angle, and the target attitude data and the Target data Pf for the lower part 9 of the tip of the power tool is created from the obtained target position data.

If the work tool has not passed through the restraint point Pc before starting the restraint operation, the horizontal orientation of the work tool is gradually changed and moved so that the work tool passes through the restraint point Pc, and the posture is controlled before performing the above process. I do.

Next, the target data P of the work tool is transformed into reverse coordinates, and the
The process of determining the amount of movement of each of the m-structures of rotation, extension and contraction, and elevation and elevation will be explained based on FIG. The starting point Ps, which is the position and orientation of the lower tip 9 of the power tool, has already been determined by the joint variables Xo (traveling axis travel distance), Y2 (extension axis extension amount), θI (swivel axis rotation angle), and θ3 (lifting axis rotation angle). Since it is found as a function, by performing an inverse coordinate transformation that performs this inverse operation,
Target values of the joint variables XQ, y2, θ1, and θ3 can be determined from the target data Pf, which is the zero position and orientation of the lower tip 9 of the work tool. From this target value and the current value detected by the resolver, the amount of operation to be performed on the servo amplifier is calculated by M and delivered to the servo amplifier to drive the servo motor or servo cylinder.

As described above, the turning angle is determined so that the work tool passes through the constraint point, and the target data is created from that turning angle, so the joint variables determined by inverse coordinate transformation are always the turning angle that passes through the constraint point. Therefore, even if the lower part 9 of the tip of the working tool is moved freely three-dimensionally, the working tool 8 will move across the perpendicular line 32 passing through the restraint point Pc, and will not collide with both sides of the arc furnace working opening 15, and will be able to remove the slag. , stirring and other operations.

Next, some more specific methods will be described regarding the process of defining the perpendicular line 32 near the work opening.

The first method is to tilt as shown in Figure 8! I.J.
Obtain the longitudinal cross-section of the work opening of t& in the front-back direction. As long as the arc furnace is symmetrical, it is naturally preferable to place this longitudinal section in the center of the working opening. demand. This constant height H is arbitrary, but since the work opening is sloped, the ratio of the next internal or external division will differ depending on the height H. Wall surface 3
A point obtained by internally or externally dividing the intersection point pb with . Internal division is A in Figure 6.
The outer portion corresponds to B or C in the figure. Generally, it is preferable to cut at a horizontal line at the height of the bank, that is, the height of the inner wall of the work opening, and divide it into 1:1 ratio. The current height can also be automatically input from the starting point Ps obtained from the current values of the joint variables 7 As a second method, find the longitudinal cross section of the working opening when the arc furnace is in a horizontal position, and compare the vertical cross section with the working opening inner wall surface 30'(' indicates before tilting. The same applies hereinafter.
), the point Pb' at a constant height H' moves to after the arc furnace is tilted, is determined by coordinate transformation, and the illumination point P
Find the intersection point Pa of the horizontal line passing through b and the outer wall surface 31 of the working opening after tilting, divide the points pb and Pa internally or externally, and use the internal or external division point as the constraint point Pc to draw a perpendicular line. can be determined. According to such a method, the perpendicular line automatically moves as the arc furnace tilt angle changes, and the above-mentioned constant height H' is preferably set to 9' below the tip of the working tool when the arc furnace is in a horizontal position. It is also possible to automatically input the height as the height of the work opening 2, which is effective when visual inspection of the inside of the work opening is not possible.

In other words, the method of setting in the horizontal position is effective when the natural flow of slag begins after tilting and the bank becomes invisible.

As a third method, a perpendicular line can be automatically determined by using the current position of the lower tip 9 of the power tool that has been visually positioned at the work opening as a constraint point PC, without depending on the tilting angle data of the arc furnace. As method 4, find the position of the lower tip 9' of the working tool when the arc furnace is in a horizontal position, calculate the point where the lower tip 9' moves after the arc furnace is tilted, and find the illumination point by coordinate transformation. A perpendicular line can also be defined as the constraint point Pc. When using this method, the location of the perpendicular line can be visually confirmed.

It is clear from the above description that the present invention is not limited by the difference in mechanical configuration between the slag removal device and the arc furnace, and that the present invention is not limited to the difference in mechanical configuration between the slag removal device and the arc furnace, and the present invention is not limited to the present invention. Therefore, it is easy to implement the present invention in any configuration, and therefore the effects of the present invention are remarkable.

[Effects of the Invention] By the control method of the sludge removal device according to the present invention, the problem of collision between the work tool inserted into the arc furnace and the arc furnace working opening can be easily and reliably avoided, and therefore no slag floating on the surface of the molten metal in the arc furnace can be avoided. Removal of slag, stirring of molten metal, and other incidental operations can be performed easily and in a short time.

[Brief explanation of the drawing]

Figures 1 and 2 are a side view and a plan view, respectively, of an example of an arc furnace and a slag removal device, with the arc furnace showing a cross section, and Figure 3 is a hardware configuration for controlling the sludge removal device. A block diagram showing an example, FIG. 4 is a perspective view for explaining the process of determining the position and orientation of an arbitrary location of the arc furnace with respect to the stationary coordinate system by coordinate transformation from the specifications of the arc furnace, the tilting mechanism, and the tilting angle; FIG. 5 is an explanatory diagram of the process of determining the position and orientation of the lower part of the tip of the working tool with respect to the stationary coordinate system by coordinate transformation from the specifications of the sludge removing device and the current position of each mechanism, and FIG. 6 is an illustration of the control method of the present invention. FIG. 7 is a block diagram showing the control method of the present invention, FIG. 8 is an explanatory diagram showing one method of determining a constraint point, and FIG. 9 is a conventional method. It is a side view which shows an example.

Claims (7)

[Claims] (1) A cart disposed facing the working opening of the arc furnace trunk and movable left and right; a working tool mounted on the cart via a turning mechanism, a telescoping mechanism, and an elevating mechanism; , a control method for an arc furnace slag removal device comprising a control device for controlling rotation, expansion/contraction, and elevating mechanisms, the method relates to a stationary coordinate system by coordinate transformation from the specifications of the arc furnace, the tilting mechanism, and the tilting angle. Determine the position of the work opening after tilting, determine the direction of the work tool on a horizontal plane with respect to the stationary coordinate system by coordinate transformation from the specifications of the sludge removing device and the current positions of the travel and rotation mechanisms, and A perpendicular line is defined near the work opening after tilting, a target position of the power tool is determined under the constraint condition that the power tool is positioned intersecting the perpendicular line, and the target position is inverse coordinate transformed to determine the traveling and A control method for an arc furnace slag removal device that determines the amount of operation of each rotating mechanism. (2) The step of determining the perpendicular line in the vicinity of the work opening after tilting involves determining a longitudinal cross section of the working opening after tilting, determining a horizontal line by cutting the vertical cross section at a horizontal plane of a constant height, and determining the horizontal line. The control of the sludge removal device for an arc furnace according to claim 1, wherein the intersection point between the inner wall surface and the outer wall surface of the working opening is divided internally or externally, and the point is defined as a perpendicular line passing through the internal dividing point or the external dividing point. Method. (3) The method for controlling an arc furnace slag removal device according to claim 2, wherein the constant height is automatically input as the current height of the lower tip of the working tool. (4) The step of determining the perpendicular line near the working opening after tilting involves determining the vertical cross-section of the working opening in the front-rear direction when the arc furnace is in a horizontal position, and drawing the perpendicular line on the intersection line between the vertical cross-section and the inner wall surface of the working opening. Find the point at which a point at a certain height moves after tilting the arc furnace by coordinate transformation, and internally or externally divide this point and the intersection of the horizontal line passing through this point and the outer wall surface of the working opening after tilting, Claim 1 is defined as a perpendicular line passing through the internal dividing point or external dividing point.
A method of controlling the slag removal device for an arc furnace described above. (5) The method for controlling an arc furnace slag removal device according to claim 4, wherein the fixed height is automatically input as the height of the lower tip of the working tool when the arc furnace is in a horizontal position. (6) The control of the slag removal device for an arc furnace according to claim 1, wherein the step of determining the perpendicular line near the work opening after the tilting is automatically determined as a perpendicular line passing through the current position of the lower tip of the working tool. Method. (7) The step of determining the perpendicular line near the work opening after tilting involves finding the position of the lower tip of the working tool when the arc furnace is in a horizontal position, and determining the point at which the lower tip will change after the arc furnace is tilted. 2. The method of controlling an arc furnace sludge removal device according to claim 1, wherein is determined by coordinate transformation and is determined as a perpendicular line passing through the point.