JPS60177905A - Shape control device of strip - Google Patents

Abstract

PURPOSE:To increase an external force used for controlling by forming the front end of a blowing nozzle into a slit shape such as an annular one and slanting the fluid blowing direction to direct it to the center of the nozzle as well as throttling the cross-sectional area of an opening. CONSTITUTION:Members 11, 12 are unified through a copper packing 18 to form a slit nozzle 13. The construction of the front end of nozzle 13 is formed into a slit shape consisting of an annular, elliptic, or rectangular shape, and its fluid- blowing direction is slanted so as to direct it to the center of nozzle 13. The slit gap is positively throttled into a small one to obtain a high blowing speed at the outlet of nozzle. Accordingly, an external force acting on a strip 10 is increased by a static pressure S' in the vicinity of the nozzle 13 center and the change of momentum due to the change of blowing direction. A large external force is applied by adjusting the gap between the strip 10 and the nozzle 13 with the aid of the packing 18, to control the shape of strip 10 without producing flaws.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to the cold rolling of copper strips, etc.
The present invention relates to a shape control device for a rolling mill, particularly to a control nozzle device, for controlling the shape of an IJ g and obtaining a product shape with good flatness.

[Prior art]

A conventional method for controlling the shape of a copper strip in a cold rolling mill is to add tension distribution. The addition of this tension distribution is an extremely effective means when viewed as a means for controlling the shape of cold rolling, and an example thereof will be described with reference to FIG.

FIG. 1 is an explanatory diagram showing shape control in a conventional cold rolling mill. 1 in Figure 1 is rolled.
Show J Tsu 1 and proceed in the direction of the arrow in the figure. 2 and 2' are work rolls which are the constituent elements of the rolling mill, and there are two of them, upper and lower.

6 and 3' are back up rolls that support work rolls 2 and 2' and provide rigidity.

Reference numeral 4 indicates a roll for holding the tension meter, which is usually installed on the exit side of the rolling mill, and 5.6 indicates a presser roll for holding the tension meter roll 4. It is called a measurement unit.

Further, 7 and 7' are divided rolls for applying tension distribution, and in the illustrated example, two rolls are arranged symmetrically with respect to the strip center. When raising and lowering the strip and pushing up the end of the strip, the line tension is concentrated at the end of the strip, so
The growth rate of Best Strip Edge is greater than that of Strip Center. Therefore, 7 and 7' tension distribution control rolls (Ten5ion distribution co.
ntrol; hereinafter referred to as TDC. ) is not applied to the strip, that is, when the strip shape is rolled with a tendency to medium elongation, a flat strip is obtained when the TDC roll is applied.

Furthermore, press the TDC roll more firmly against the strip,
By displacing only the strip ends upwards and to a greater extent,
When the degree of action of the TDC roll is increased, the shape of the plate after rolling tends to have an undulating shape. By controlling the TDC roll in this manner, it is possible to freely control the strip shape, and this idea itself has already been disclosed by the applicant in Japanese Patent Publications No. 55-32442 and No. 58-28005.

Historically, in place of the TDC rolls 7 and 7' shown in FIG. A method of injecting a cooling medium or the like and colliding the jet stream with the strip, for example, a method disclosed in Japanese Patent Application Laid-Open No. 167012/1983, has also been carried out.

This method has advantages over the method using split rolls: (1) Since external force is applied to the strip via fluid such as water, there is no mechanical contact between the TDC rolls. No scratches.

(2) Generally, for TDC rolls, the shape control effect is more pronounced when the external force is applied closer to the roll bit of the rolling mill.

In this respect, the split rolls 7, 7', including their supporting and pressing mechanisms, have a certain size, and there is a limit to how close they can be to the roll bite. In comparison, jet nozzles are relatively compact and can be self-contained closer to the roll bite than split rolls.

etc.

FIG. 2 shows an example using a TDC (hereinafter referred to as fluid pressure TDC in the sense of using the pressure caused by the fluid) by a jet flow from this nozzle. Note that the same reference numerals in FIG. 2 as in FIG. 1 indicate the same or the same functions, and their explanation will be omitted. In Fig. 2, 8 is a nozzle for ejecting a jet of fluid = b It is provided in place of the split roll 7 in Fig. 1, and as in Fig. 1, another nozzle is installed symmetrically with respect to the strip center. A nozzle 8' is installed. 9.9' is a reservoir piping that supplies fluid to each nozzle 8.8', and here it has a pressure resistance of 600 kg/
Although not shown, the nozzles 8 and 8' are mounted near the roll bite by means of a suitable support frame.

FIG. 6 (b) is a schematic diagram showing a specific jetting state of the nozzles 8 and 8' used for such fluid pressure TI)C.

FIG. 6(a) is the simplest type, and is an example using a normal tapered nozzle. In FIG. 6(A), a high-pressure fluid (hereinafter referred to as "fluid") is a coolant liquid, which is an emulsion of water and rolling oil used in normal cold rolling, and is passed through a small hole at the tip of the nozzle. ) is ejected and collides with strip 1.

At this time, the jet from the nozzle 8 collides with the IJl knob 1 and changes its direction, so the change in momentum of this high-speed jet becomes the external force applied to the IJl knob 10. -), the gap g at the opening of the nozzle is set sufficiently large without narrowing it too much, so the distance #d between the strip 1 and the nozzle 8 determines the ejection pressure of the nozzle.

Further, in the nozzle shown in FIG. 6(b), a quiet pressure field having a certain area is formed between the nozzle 8 and the strip 1 (the pressure in this quiet pressure field is shown as PQ in the figure). 1
．． Therefore, as an external force applied to the strip, a force corresponding to the area So X Po is applied.

In comparing both Figures 6 (a) and (b), as will be described in detail later, under the constraints of the maximum pressure and maximum flow rate of the fluid supplied to the nozzle, the quiet pressure field of Figure 6 (b) The utilization type nozzle is more advantageous than the nozzle shown in FIG. 6(a) because it has a higher efficiency in applying an external force to the strip.

However, the higher the efficiency of applying this external force, the higher the power (kw) of the high-pressure ponder for generating fluid pressure.
), which is advantageous, and a nozzle with even higher efficiency has been desired.

In addition, for both the nozzles in Fig. 6 (a) and (b), the center MC-C'
Therefore, the nozzle in Fig. 6 (a) has a circular ejection hole, but the nozzle in Fig. 6 (b) has an annular slit shape. There is.

[Summary of the invention]

The present invention provides a highly efficient nozzle device for controlling the shape of a strip and obtaining a product with good flatness by using a control device that applies an external force using a fluid pressure TDC roll in cold rolling of steel strips, etc. The purpose is to

The gist of the present invention is to use a nozzle whose tip is annular, elliptical, or rectangular and has a slit shape in the above-mentioned control device for applying an external force, and to tilt fluid ejected from the nozzle in a specific direction. , a strip shape control device characterized by using a jet nozzle having a narrowed cross-sectional area so as to obtain a maximum discharge pressure.

[Embodiments of the invention]

The present invention will be described based on FIG. 4, which is an embodiment example.

FIG. 4 is a schematic diagram for explaining the basic concept of the nozzle according to the present invention. This nozzle is similar to FIG. Has an opening.

(11) As shown in the figure, the slit is inclined at an angle θ so as to face the center of the nozzle.

(lυ Therefore, the jet coming out of the slit is directed diagonally toward the center of the nozzle) 17 Colliding with the spout 1, there is no place for escape on the nozzle center side, so the jet changes direction drastically as shown by the arrow. , bathe in strips and flow away radially outward.

(IVl at the same time) IJ g1 and the bottom of the nozzle (
B in the figure), a pressure chamber (quiet pressure field) is formed in the center of the nozzle by the water film of the jet.

(Let this pressure be Po') (V) Effective area of the pressure chamber (S in the figure (indicated by) and Po'
The nucleus of ' acts on S) 13 as an external force.

The major difference from nozzle 8 in Figure 3 (b) is that the slit gap (indicated by g' in the figure) has been actively made smaller, allowing a high jet flow velocity to be obtained at the slit nozzle outlet. be.

Therefore, in addition to the external force as a static pressure proportional to So'

Table 1 shows the nozzle shown in Fig. 4 according to the present invention (hereinafter referred to as (c) nozzle) and the conventional nozzle shown in Fig. 6 (h) (b) (hereinafter ←)
(b) When the strip is pushed up by a nozzle), it shows the force that is theoretically calculated from the force that acts on the IJ knob.

Table 1 Table 1 shows the distance Md (gap) between the Stroke II knob and the nozzle, and the outer crab F (
kg).

The conditions in Table 1 are as follows.

(1) The maximum discharge pressure of all nozzles is 150 &/ca
, the maximum discharge flow rate is 1007/sdg (2) The shape of each nozzle opening is circular with an inner diameter of 6.5Hψ.

The nozzle (b) is 37.7N x 1.01Jl (the diameter of the annular slit nozzle is 12.0-aψ), and the nozzle (c) is 37.7, X O, 26mg (the diameter of the slit nozzle is ( b) Same as <12.0−ψ
)(3) The opening cross-sectional area of each nozzle is approximately 97-(b) for both the nozzle (a) and the nozzle (c), which is approximately four times that, 37.7J (4) (b), The inclination angle θ of the nozzle in (c) is set to 6°.

As shown in Table 1, the nozzle ('I) is
A constant force of 29 kg is obtained regardless of the distance (d) from the lip, but in the nozzle (b), the smaller d is, the higher the pressure Po in the pressure field becomes, and as d decreases, the pressure Po The force acting on the strip increases.

However, in the nozzle (b), the dead pressure field is extremely small in the region where d is large, and the jet discharge velocity from the nozzle opening is also small, so the change in momentum due to the collision of the jets is also small, compared to the nozzle (b). Only a small amount of power can be obtained.

In the nozzle (c) of the present invention, even in the region where d is large, the force due to the change in momentum due to the change in direction of the high-speed jet and the effect of the force due to the quiet pressure field are suppressed over the entire range of d shown in the m1 table. Since they appear in a superimposed manner, it can be seen that a significantly larger force F (kg) can be obtained from the nozzles (a) and (b).

However, when d becomes small to about 0.2-, (b),
The force obtained by the nozzle (c) is saturated at a value of about 184 km.

In reality, this theoretical characteristic is also related to the flow resistance due to the viscosity of the fluid, the conversion of kinetic energy to thermal energy due to turbulence, and the machining accuracy of the nozzle, so it is better than this calculated value. It's slightly off.

Figure 5 shows the results of an experiment conducted by the inventors using a prototype nozzle under the same conditions as in Table 1.
The calculated values in Table 1 are also shown at the same time.

The experimental value shows that when d is less than 0.211 J, there is a problem in measuring d at 8 degrees. In other words, there is a possibility that the nozzle and the strip are in partial mechanical contact, and the measured value lacks reliability, but in the region where d is large, it agrees well with the theoretical value, and the ←→ nozzle of the present invention Its effectiveness is highly praised.

When actually operating fluid pressure TDC in a rolling mill, it is preferable that the distance between the strip and the nozzle be as large as possible. In other words, if there is mechanical contact between the nozzle and the strip, it will damage the surface of the IJ tube and impair the quality of the product. In this sense, the nozzle (c) can obtain a larger F (ky) than the other nozzles even if d is a large value, and is suitable for the purpose of fluid pressure 'f' DC.

Next, FIG. 61 and FIG. 7 show the schematic structure of a nozzle according to the present invention installed in an actual rolling mill.

FIG. 6 is a plan view of the nozzle of the present invention, and FIG. 7 is a sectional view taken along line A-A.

In FIGS. 6 and 7, 10 indicates an IJ, and 11 and 12 indicate nozzle constituent members, which are made of SUS. These two members 11 and 12 constitute an annular slit nozzle, and the inclination angle θ (see Fig. 4)
is 45° in this embodiment.

The structural members 11 and 12 are integrally constructed with screws 19 via a copper gasket 18, and constitute a slit nozzle 16, and the gap between the slits 16 can be adjusted by adjusting the thickness of the gasket.

The fluid to be supplied to the nozzle is supplied to a high-pressure hose shown at 15 connected by a tapered screw, and is guided from a part of the header (spanning the entire circumference) at 16° 17 to the nozzle outlet as shown by the arrow. The external shape of this nozzle is 70. The diameter of the annular slit nozzle (d in the figure) is 10 mφ.

The slit gap is 0.6 mm.

The connection port 15 is a V2 inch taper screw for piping.0 According to this nozzle configured in this way, by adjusting the distance between the slip I/lip and the nozzle, a large external force can be applied to the strip. It became possible to control the shape of the strips without causing any flaws.

In this embodiment, the structure and operation of one slit nozzle have been described, but it goes without saying that a plurality of slit nozzles may be installed at any position in the width direction of the strip. Although a circular concession nozzle is used as the shape of the slit nozzle, this shape does not necessarily have to be circular; for example, it can be oval, or in extreme cases, it can be square.
By changing the shape, the cross-sectional area of the nozzle opening is narrowed, causing the high-speed fluid to collide with the IJ tube, and at the same time tilting the direction of the jet toward the center of the nozzle to generate a static pressure field. By doing so, the expected effects of the present invention can be fully exhibited.

〔Effect of the invention〕

The IJ tube shape control device (using the injection nozzle according to the present invention) also has a larger discharge pressure α9 compared to the conventional tension distribution control @l type strip control device using fluid pressure.

It is useful because it can apply a significantly large external force, and enables smooth rolling control of metal strips such as cold-rolled copper strips without any defects.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a conventional strip shape control method, Fig. 2 is an explanatory diagram of a strip shape control method using fluid pressure TDC, and Figs. 3 (a) and (b) are schematic diagrams showing the injection state by a conventional nozzle. Figure 4 is an explanatory diagram of the basic concept of the nozzle of the present invention, Figure 5 is a graph of the force applied to the strip when the distance between the strip and the nozzle is changed for the nozzle of the present invention and the conventional nozzle, and Figure 6 is The plan view of the nozzle of the present invention, FIG. 7, is a view taken along the line A-A in FIG. 6. 1.10... Strip, 7,7'... Roll for tension distribution control, 8.8'... Nozzle, d... Distance between strip and nozzle, F... Force applied to strip po
... Pressure in a quiet pressure field, 11.12 ... Nozzle component, 13 ... Slit nozzle, 15 ... High pressure hose 17 ... Header, 18 ... Packing, 19 ...
Screws in the middle of each figure - The same reference numerals indicate the same functions.Representative Patent Attorney Sanro Kimura

Claims (2)

[Claims] (1) In cold rolling of thin steel plates, etc., a fluid jetting nozzle is provided on the exit side of the rolling mill, and the fluid jetted from the nozzle collides with the strip, and the fluid applies an external force to the strip, thereby increasing the width of the strip. In the strip control device for adjusting the tension distribution in the direction, the structure of the tip of the fluid ejection nozzle is a slit shape consisting of an annular, elliptical or rectangular shape, and the fluid ejection direction of the nozzle is inclined so as to face the center of the nozzle. , and a nozzle opening cross-sectional area is narrowed so that the discharge flow rate of the nozzle corresponds to the pump maximum discharge pressure of the jet fluid. (2) The fluid ejection nozzle slit has an angle of 60° to 45Q with respect to the center line of the nozzle. (3) The distance between the string and the fluid ejection nozzle is 0.2 to 0.
6. A patent application characterized in that