KR101193862B1

KR101193862B1 - Apparatus for measuring speed of strip

Info

Publication number: KR101193862B1
Application number: KR20100073181A
Authority: KR
Inventors: 박영국; 임갑수; 조승한
Original assignee: 현대제철 주식회사
Priority date: 2010-07-29
Filing date: 2010-07-29
Publication date: 2012-10-26
Also published as: KR20120011412A

Abstract

The present invention relates to a strip speed measuring apparatus, which is located at an exit side of a finishing mill and is disposed below a conveying path of a strip sent from a finishing mill to measure a speed of the strip by an induced current generated when the strip is transferred. A phase injection section disposed at the exit side of the finishing mill and disposed at the front side of the speed measurement section and injecting fluid toward the top of the strip to remove foreign substances on the upper surface of the strip, and at the exit side of the speed measurement section at the exit side of the finishing mill. And a bottom injection portion disposed to spray the fluid toward the bottom of the strip to remove foreign matter from the bottom surface of the strip.
According to the present invention, the speed of the strip sent out from the finishing mill can be accurately measured in real time using an induction current.

Description

Strip speed measuring device {APPARATUS FOR MEASURING SPEED OF STRIP}

The present invention relates to a strip speed measuring apparatus, and more particularly, to a strip speed measuring apparatus for measuring the speed of the strip sent from the finishing mill using the induction current.

Typical steelmaking consists of a steelmaking process to produce molten iron, a steelmaking process to remove impurities from molten iron, a continuous casting process to make solid iron into solid, and a rolling process to make iron into steel or wire.

The rolling process is a process of passing an intermediate material such as a slab, a bloom, etc. produced in a continuous casting process through a plurality of rotating rollers and applying a continuous force to increase or decrease the thickness thereof. The rolling process is roughly classified into hot rolling and cold rolling.

The above technical configuration is a background art for helping understanding of the present invention, and does not mean a conventional technology well known in the art.

An object of the present invention is to provide a strip speed measuring apparatus that can accurately measure the speed of the strip sent from the finishing mill in real time using an induction current.

The strip speed measuring apparatus according to the present invention is located at the exit side of the finishing mill and disposed below the conveying path of the strip sent out from the finishing mill to measure the speed of the strip by the induced current generated during the feeding of the strip. Speed measuring unit; An injector disposed at an outlet side of the finishing mill and disposed at a front side of the speed measuring unit and configured to spray a fluid toward an upper portion of the strip to remove foreign substances from an upper surface of the strip; And a lower injection part disposed at an outlet side of the finishing mill and disposed at the front side of the speed measurement part, and spraying a fluid toward the lower part of the strip to remove foreign substances on the lower surface of the strip.

Preferably, the speed measuring unit, iron core; A primary coil wound on one side of the iron core; A secondary coil wound on the other side of the iron core; A reference current applying unit which applies a reference current to the primary coil; An induction current measuring unit measuring an induction current induced in the secondary coil by the transfer of the strip; And a speed calculator configured to receive the induced current from the inductive current measuring unit and calculate the speed of the strip.

More preferably, the iron core is formed in a U-shape, the primary coil is wound on one end of the iron core, the secondary coil is wound on the other end of the iron core, one end and the other of the iron core The end is arranged perpendicular to the feed path of the strip.

More preferably, the speed measurement unit further comprises a protection unit for protecting the foreign matter, the protection unit, surrounding the speed measurement unit, injecting a fluid above the speed measurement unit to block the falling of foreign matter in the speed measurement unit Protective spray; A protective cover that includes the speed measuring unit and exposes the speed measuring unit to the outside according to whether the speed measuring unit is operated; And an opening / closing member which slides the protective cover so that the speed measuring part is exposed to the outside when the speed measuring part is operated.

More preferably, the upper injection portion is movable up and down to adjust the height according to the thickness of the strip.

More preferably, the phase injection unit, the spray phase spraying the fluid toward the upper portion of the strip; A connecting rod on which the upper spray is mounted; A drive unit installed in the connecting rod; A rotary gear part connected to the driving part and rotated by driving of the driving part; And a rack gear part engaged with the rotary gear part and guiding the vertical movement of the rotary gear part.

According to the present invention, it is possible to accurately measure the speed of the strip sent from the finishing mill through the speed measuring unit in real time.

In addition, according to the present invention, it is possible to accurately measure the speed of the strip in real time, it is possible to solve the problem of strip quality defects, such as malfunction of the equipment, strip breaking or strip overlap.

In addition, according to the present invention, since the speed measuring unit operates in a non-contact state with the strip, it is possible to block the degradation of durability due to the collision with the strip, thereby achieving time and material cost reduction in terms of maintenance and repair of the equipment.

In addition, according to the present invention, since the foreign matter remaining on the surface of the strip is removed by the upper injection section and the lower injection section before the strip passes through the speed measurement section, it is possible to accurately measure the speed of the strip.

In addition, according to the present invention, it is possible to block the falling of the foreign matter to the speed measuring unit during the operation of the speed measuring unit through the fluid spray in the protective spray it is possible to prevent the accuracy of the strip speed measurement due to the foreign matter.

In addition, according to the present invention, the speed measuring unit is prevented from being exposed to the outside through the protective cover when the speed measuring unit is inoperative, thereby preventing contamination of the speed measuring unit by foreign matter.

1 is a view schematically showing a strip speed measuring apparatus according to an embodiment of the present invention.
Figure 2 is a block diagram schematically showing a speed measuring unit in the strip speed measuring apparatus according to an embodiment of the present invention.
3 is a graph showing a proportional relationship between an induced current and a strip speed in the strip speed measuring apparatus according to an embodiment of the present invention.
4 is a view showing a speed measuring unit and a protection unit in the strip speed measuring apparatus according to an embodiment of the present invention.
5 is a view showing a state in which the protective cover is opened in the strip speed measuring apparatus according to an embodiment of the present invention.
6 is a view showing a state in which the protective cover is closed in the strip speed measuring apparatus according to an embodiment of the present invention.
7 is a view showing a state in which the image injection unit is positioned when the thick strip is sent in the strip speed measuring apparatus according to an embodiment of the present invention.
8 is a block diagram showing a control flow of the strip speed measuring apparatus according to an embodiment of the present invention.

Hereinafter, an embodiment of a strip speed measuring apparatus according to the present invention will be described with reference to the accompanying drawings. In this process, the thicknesses of the lines and the sizes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation.

Further, terms to be described below are defined in consideration of the functions of the present invention, which may vary according to the intention or custom of the user, the operator. Therefore, the definitions of these terms should be made based on the contents throughout the specification.

1 is a view schematically showing a strip speed measuring apparatus according to an embodiment of the present invention, Figure 2 is a block diagram schematically showing a speed measuring unit in the strip speed measuring apparatus according to an embodiment of the present invention, Figure 3 Is a graph showing the proportional relationship between the induced current and the strip speed in the strip speed measuring apparatus according to an embodiment of the present invention. 4 is a view showing a speed measuring unit and a protection unit in the strip speed measuring apparatus according to an embodiment of the present invention, Figure 5 shows a state in which the protective cover is opened in the strip speed measuring apparatus according to an embodiment of the present invention. 6 is a view showing a state in which the protective cover is closed in the strip speed measuring apparatus according to an embodiment of the present invention. FIG. 7 is a view illustrating a state in which an upper injection part is positioned when a thick strip is sent out in a strip speed measuring apparatus according to an embodiment of the present invention, and FIG. 8 is a view illustrating a strip speed measuring apparatus according to an embodiment of the present invention. A block diagram showing the control flow.

1 and 8, the strip speed measuring apparatus 1 according to an embodiment of the present invention includes a speed measuring unit 10, an upper injection unit 20, a lower injection unit 30, a protection unit 40, It comprises a control unit 50.

The speed measuring unit 10 is located at the outlet side of the finishing mill F and is disposed below the conveying path of the strip S sent from the finishing mill F. The speed measuring unit 10 measures the speed of the strip S based on the induced current generated when the strip S is transferred.

2, 3 and 8, the speed measuring unit 10 includes an iron core 11, a primary coil 12, a secondary coil 13, a reference current applying unit 14, and an induction current measuring unit ( 15), the speed calculating section 16 is included.

The iron core 11 is disposed to be spaced apart from the strip S, which is transferred to the post process by the feed roller R at a predetermined interval. The iron core 11 is formed in a U shape, and both ends thereof are disposed toward the strip S. The iron core 11 is wound around the primary coil 12 at one end and the secondary coil 13 at the other end.

Since one end and the other end of the iron core 11 are disposed orthogonal to the transfer path of the strip S (see FIG. 2), the velocity measurement of the strip S using an induced current can be made more accurately.

The primary coil 12 generates a magnetic flux of a constant magnitude when a reference current is applied from the reference current applying unit 14. Induction current is generated in the secondary coil 13 by the change of the magnetic flux generated in the primary coil 12 as the strip S is transferred.

The reference current applying unit 14 applies a constant reference current to the primary coil 12, and the induction current measuring unit 15 is adapted to the change in the magnetic flux generated in the primary coil 12 during the transfer of the strip S. By measuring the induced current induced in the secondary coil (13).

The controller 50 controls the reference current applying unit 14 so that the reference current is applied to the primary coil 12, and the speed calculator 16 receives the induced current from the inductive current measuring unit 15 and strips S Calculate the speed of Since the induced current is proportional to the amount of change in the magnetic flux over time, the speed of the strip S may be calculated inversely through the magnitude of the induced current as shown in FIG. 3.

The speed calculator 16 provides the calculated speed of the strip S to the controller 50, and the controller 50 speeds the rolling roll (not shown) of the finishing mill F based on the speed of the provided strip S. By controlling the respective to prevent the phenomenon such as strip overlap or strip breakage between each rolling stand of the finishing mill (F).

The phenomenon in which a current is generated in a conductive wire by a change of magnetic flux is called an induction current. The induction current is obtained by Equation 1 below.

here,

Is the induced current, n is the number of turns,

Is the change in magnetic flux,

Is the amount of change in time, and the induced current is proportional to the number of turns of the coil and the amount of change in the magnetic flux per unit time.

The velocity measuring unit 10 according to the present embodiment measures the magnitude of the induced current generated in proportion to the amount of change in the magnetic flux per unit time, and thus the strip is sent from the finishing mill F through the principle of calculating the speed of the metal body inversely. Measure the speed of (S).

Operation of the speed measuring unit 10 is performed as follows. The reference current applying unit 14 supplies a constant reference current to the primary coil 12 having the number of turns n. As a result, a magnetic flux having a constant magnitude is generated in the primary coil 12.

At this time, when the strip S passes through the iron core 11, a change occurs in the magnetic flux generated by the primary coil 12. That is, an induction current is generated in the secondary coil 13 in proportion to the change of magnetic flux with time.

The speed calculator 16 calculates the speed of the strip S inversely based on the magnitude of the induced current generated in the secondary coil 13, and transmits it to the controller 50.

As such, the speed measuring unit 10 of the present invention can measure the speed of the strip S without contacting the strip S, thereby reducing the degradation of durability that may be caused by contact with the strip S. Can be blocked at source. This can result in time and material cost savings in terms of equipment maintenance and repair.

In addition, the present invention can accurately measure the speed of the strip (S) in real time by the speed measuring unit 10, it is possible to control the rolling roll speed of the finishing mill (F) based on this strip between each rolling stand The problem of strip failure due to overlapping or strip breaking can be solved.

The speed measuring unit 10 is supported by the support 10a. The support 10a supports the speed measuring unit 10 from the lower side so that the distance between the speed measuring unit 10 and the lower surface of the strip S is always constant.

Referring to FIG. 1, the phase injector 20 sprays a fluid toward the upper portion of the strip S to remove foreign substances on the upper surface of the strip S. Referring to FIG. The phase injecting unit 20 is located at the outlet side of the finishing mill F and is disposed at the front side of the speed measuring unit 10.

As a result, foreign substances such as water on the surface of the strip S are removed by the fluid injected at a high pressure before the strip S reaches the speed measuring unit 10, so that the speed measuring unit 10 is not affected by the foreign substances. Thus, the speed of the strip S can be accurately measured.

The phase injection part 20 is installed in the external device C to be movable up and down to adjust the height according to the thickness of the strip S. Therefore, when there is a change in the thickness of the strip (S) according to the upper injection portion 20 is moved upwards or downwards, the upper surface of the upper injection portion 20 and the strip (S) always maintain a constant interval.

The phase injector 20 includes an upper spray 21, a connection table 22, a driver 23, a rotary gear 24, and a rack gear 25.

The upper spray 21 is connected to an external fluid source and injects the fluid supplied therefrom toward the upper surface of the strip S. The upper spray 21 is provided with a nozzle (not shown). The upper spray 21 is installed at the lower portion of the connecting table 22, and the driving unit 23 is installed at the upper portion. In this embodiment the fluid is air.

The driving unit 23 is installed on the connecting table 22 to generate power for rotating the rotary gear unit 24. The driving unit 23 includes a driving motor generating power, and supplies the generated power connected to the rotary gear unit 24 to the rotary gear unit 24. The operation of the upper spray 21 and the driving unit 23 is controlled by the controller 50.

The rotary gear unit 24 is connected to the driving unit 23 and rotated by the power generated by the driving unit 23. In this embodiment, the rotary gear 24 is illustrated as a pinion gear.

The rack gear part 25 is configured to engage the rotary gear part 24 to guide the lifting and lowering of the rotary gear part 24 according to the rotation of the rotary gear part 24. To this end, the rack gear portion 25 is provided with a guide portion (not shown) to prevent the separation of the rotary gear portion 24.

The rack gear portion 25 is fixed to the external device (C). The external device (C) is a device that can firmly secure the rack gear portion 25 to prevent the rack gear portion 25 from shaking when the upper injection portion 20 moves up and down, for example, the transfer roller (R) It may be a roller table for supporting.

In the present exemplary embodiment, the driving unit 23 connected to the rotary gear unit 24 is installed on the connecting table 22 and the rack gear unit 25 is fixed to the external device C. However, the present invention is not limited thereto. Accordingly, the driving unit 23 connected to the rotary gear unit 24 is fixed to the external device C, and the rack gear unit 25 is configured to be coupled with the upper sprayer 21. Of course, various modification embodiments are possible.

The lower injection part 30 injects fluid toward the lower part of the strip S to remove foreign substances on the lower surface of the strip S. The lower injection section 30 is located on the exit side of the finishing mill F and is disposed on the front side of the speed measurement section 10.

Thus, before the strip S sent from the finishing mill F reaches the speed measuring unit 10, foreign substances such as water on the surface of the strip S are removed by the fluid sprayed at a high pressure. 10) is not affected by the foreign matter can be accurately measured the speed of the strip (S).

The lower injection unit 30 includes a spray spray 31 and a pedestal 32. The lower spray 31 is connected to an external fluid source and injects the fluid supplied therefrom toward the lower surface of the strip S. The heart spray 31 is provided with a nozzle (not shown), and operation is controlled by the controller 50.

The pedestal 32 supports the lower spray 31 from below so that the spacing between the lower spray 31 and the lower surface of the strip S is always constant. In this embodiment the fluid is air.

4 to 6 and 8, the protection unit 40 includes a protection spray 41, a protection cover 42, and an opening / closing member 43 to protect the speed measurement unit 10 from foreign matter.

The protective spray 41 is installed inside the protective cover 42 like the speed measuring unit 10. The protective spray 41 is provided with a plurality, it is arranged to surround the speed measuring unit 10. The protective spray 41 is controlled by the control unit 50, and the protective cover 42 is opened to protect the speed measuring unit 10 when it is exposed to the outside, that is, for the operation of the speed measuring unit 10. When the cover 42 is opened, the fluid is injected above the speed measuring unit 10 so that no foreign matter falls to the speed measuring unit 10. Here, the foreign matter means dust in the air or impurities attached to the strip S.

Since a kind of protective film is formed above the speed measuring unit 10 by the fluid sprayed from the protective spray 41, foreign substances do not fall to the speed measuring unit 10, but fall out of the speed measuring unit 10. . Through this, it is possible to improve the accuracy of the strip (S) speed measurement through the speed measuring unit 10. In this embodiment the fluid is air.

The protective cover 42 selectively exposes the speed measuring unit 10 to the outside depending on whether the speed measuring unit 10 is operated. The protective cover 42 includes a fixed cover 42a and a moving cover 42b.

The fixed cover 42a incorporates the speed measuring unit 10 and the protective spray 41 and is supported by the support 10a. The moving cover 42b is slidably coupled to the fixed cover 42a. Guide rails and guide grooves having corresponding shapes may be formed in the moving cover 42b and the fixed cover 42a so as not to be separated from the fixed cover 42a during the slide movement of the moving cover 42b.

The moving cover 42b is slid by the opening and closing member 43 as shown in FIG. 5 when the speed measuring unit 10 is operated so that the speed measuring unit 10 is exposed to the outside, and the speed measuring unit 10 is If it does not operate as shown in Figure 6 slides by the opening and closing member 43 so that the speed measuring unit 10 is not exposed to the outside.

The opening and closing member 43 supplies power for the slide movement of the movement cover 42b by the operation control of the controller 50. In this embodiment, the opening and closing member 43 is illustrated as a hydraulic cylinder.

Hereinafter will be described the operation principle of the strip speed measuring apparatus according to an embodiment of the present invention.

The strip S sent out from the finishing mill F is transferred to the post process by the feed roller R. FIG. At this time, the speed measuring unit 10 for measuring the feed speed of the strip (S) is located at the outlet side of the finishing mill (F).

Before the strip S passes through the speed measuring unit 10, foreign matter remaining on the upper surface and the lower surface is removed by the upper injection unit 20 and the lower injection unit 30. The phase injector 20 maintains a constant distance between the upper spray 21 and the upper surface of the strip S by adjusting the height according to the thickness of the strip S.

The distance between the upper spray 21 and the upper surface of the strip S is equal to the distance between the lower spray 31 and the lower surface of the strip S. As shown in FIG. Accordingly, since the same fluid pressure is formed by the upper sprayer 21 and the lower sprayer 31 on the upper surface and the lower surface of the strip S, the rate at which foreign matter is removed from the surface is almost the same. The speed measurement accuracy can be further improved.

For example, as shown in FIG. 7, when the strip S sent from the finishing mill F is a thick plate compared to FIG. 1, the upper injection part 20 is moved upward by the thickness difference of the strip S. The distance between the strip S and the image spray 21 is equal to the distance in FIG. On the contrary, when the strip S is thin compared to FIG. 1, the upper injection part 20 is moved downward by the thickness difference of the strip S. FIG.

The strip S from which foreign substances on the surface are removed by the upper injection unit 20 and the lower injection unit 30 is measured while passing through the speed measurement unit 10. In order to measure the speed of the strip S through the speed measuring unit 10, the speed measuring unit 10 must be exposed to the outside, which is moved by the opening and closing member 43 through the control unit 50. 42b) slides outward. Meanwhile, when the speed measurement of the strip S is completed, the opening and closing member 43 slides the moving cover 42b inward to prevent the speed measuring unit 10 from being exposed to the outside. As a result, when the speed measuring unit 10 is not operated, the speed measuring unit 10 may be prevented from being contaminated by foreign matter.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary and will be understood by those of ordinary skill in the art that various modifications and equivalent other embodiments are possible. will be.

In addition, the strip speed measuring apparatus disposed on the outlet side of the finishing mill has been described as an example, but this is merely illustrative, and the technical spirit of the present invention may be applied to other devices other than the finishing mill. Accordingly, the true scope of the present invention should be determined by the following claims.

10: speed measurement unit 11: iron core
12: Primary coil 13: Secondary coil
14: reference current applying unit 15: induction current measuring unit
16: speed calculation unit 20: phase injection unit
21: upper spray 22: connecting rod
23: drive unit 24: rotary gear unit
25: rack gear part 30: lower injection part
40: protection part 41: protection spray
42: protective cover 43: opening and closing member
50:

Claims

A speed measurement unit disposed at an exit side of the finishing mill and disposed below the transfer path of the strip sent from the finishing mill to measure the speed of the strip by an induced current generated when the strip is transferred;
An injector disposed at an outlet side of the finishing mill and disposed at a front side of the speed measuring unit and configured to spray a fluid toward an upper portion of the strip to remove foreign substances from an upper surface of the strip;
A lower injection part disposed at an outlet side of the finishing mill and disposed at the front side of the speed measurement part, and spraying a fluid toward the lower part of the strip to remove foreign substances on the lower surface of the strip; And
It includes a protection unit for protecting the speed measurement unit from the foreign matter,
The protection unit may include: a protection spray surrounding the speed measurement unit and injecting a fluid upwardly of the speed measurement unit so that foreign matters fall into the speed measurement unit;
A protective cover that includes the speed measuring unit and exposes the speed measuring unit to the outside according to whether the speed measuring unit is operated; And
Strip opening and closing member for sliding the protective cover so that the speed measuring unit is exposed to the outside during the operation of the speed measuring unit.

The method of claim 1,
The speed measuring unit, iron core;
A primary coil wound on one side of the iron core;
A secondary coil wound on the other side of the iron core;
A reference current applying unit which applies a reference current to the primary coil;
An induction current measuring unit measuring an induction current induced in the secondary coil by the transfer of the strip; And
And a speed calculator configured to receive the induced current from the inductive current measuring unit and calculate a speed of the strip.

The method of claim 2,
The iron core is formed in a U-shape,
The primary coil is wound on one end of the iron core, the secondary coil is wound on the other end of the iron core,
One end of the iron core and the other end of the strip speed measuring apparatus, characterized in that arranged at right angles to the conveying path of the strip.

delete

The method of claim 1,
The phase injection unit is a strip speed measuring apparatus, characterized in that the vertical movement to adjust the height according to the thickness of the strip.

The method of claim 5,
The phase injection unit may include: an phase spray for injecting a fluid toward an upper portion of the strip;
A connecting rod on which the upper spray is mounted;
A drive unit installed in the connecting rod;
A rotary gear part connected to the driving part and rotated by driving of the driving part; And
And a rack gear part engaged with the rotary gear part and guiding the vertical movement of the rotary gear part.