JPH10267916A - On-line space factor measurement method for rapid metal thin band - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for measuring space factor wherein quality evaluation is made on line with ease for a rapid cooling metal thin band manufactured by jetting a molten metal on the outside periphery of a cooling roller being rotated at high speed, for rapid solidification. SOLUTION: A molten metal is supplied from a nozzle 3 to the surface of a cooling roller 4 being rotated at high speed, to be rapidly solidified, thus a rapid cooling metal thin band S is manufactured. While the rapid cooling metal thin band S is wound in spiral, the coil's weight, inside diameter, and outside diameter are measured during winding or after completion, and a space factor is calculated based on the measured value. Thus, a space factor is evaluated with ease.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring an on-line space factor of a quenched metal ribbon, and more particularly to a method for manufacturing a quenched metal ribbon by jetting a molten metal onto the outer periphery of a cooling roll which is rotating at a high speed to cause rapid solidification. The present invention relates to a space factor measuring method capable of performing a simple quality evaluation of a rapidly quenched metal ribbon on-line.

[0002]

2. Description of the Related Art Hitherto, various methods have been proposed for producing a metal ribbon from a molten metal. Among them, for producing a wide ribbon, Planar-Flow-Casting has been proposed.
The law is said to be advantageous. Important operating factors in this method are the distance between the nozzle and the roll, the moving speed of the roll, the injection pressure of the molten metal, the gap between the nozzle slits, and the like. There is a continuous casting method of a metal strip disclosed in Japanese Unexamined Patent Publication No.
This method has made it possible to produce wide quenched metal ribbons on an industrial level.

[0003] At present, for example, Fe-B-Si alloy-based alloys are well known as applications of the wide quenched metal ribbons, and the alloy-based alloys have attracted attention due to their magnetic properties of low iron loss. As a substitute for silicon steel sheets, they have been used as iron cores for pole transformers. This Fe-
The characteristics required when using a quenched metal ribbon of the B-Si alloy system as a pole-mounted transformer include magnetic properties such as iron loss and magnetic flux density, as well as sheet thickness, sheet thickness deviation, surface roughness, and fine hole opening. Shape properties such as the presence or absence of Also, in order to avoid the cost increase due to the large transformer on the pole,
It is desired to have a larger space factor, which is a comprehensive result of the above-mentioned shape characteristics.

Meanwhile, as a conventional method for evaluating the space factor LF (%), a plurality of strip-shaped samples are cut out from a ribbon, and n samples are stacked, and the thickness t _n (m
m) was measured, and a method of obtaining the value by the following equation (1) was used. LF = {W _n / (ρ · t _n · B · L)} × 100 (%) where W _n ; mass of n samples (t) ρ; metal ribbon density (t / m ³⁾ B; strip width (m) L; sample length (m) However, in this method, since each time it is necessary to measure the strip sample n sheets also superimposed, There were drawbacks that the work efficiency was poor and that measurement could not be performed online.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and it is intended to evaluate the quality of a metal strip without taking a strip-shaped sample. It is an object of the present invention to provide an online space factor measuring method of a quenched metal ribbon that can be easily performed online.

[0006]

SUMMARY OF THE INVENTION According to the present invention, when a molten metal is supplied from a nozzle to the surface of a cooling roll rotating at a high speed and rapidly cooled and solidified to produce a rapidly cooled metal ribbon, the rapidly cooled metal ribbon is formed into a coil shape. Winding, measuring the coil weight, the coil inner diameter and the coil outer diameter during or after the winding, and calculating the space factor based on the measured value by the following formula to obtain the quenched metal ribbon. Is an online space factor measurement method.

LF = 100 × (W / ρ · V) where LF; average space factor (%) W; coil weight (t) ρ; density of quenched metal ribbon (t / m ³ ) V; coil Apparent volume (m ³ ) = π · (Do ² −Di ² ) · B /
4 Do; coil outer diameter (m) Di; coil inner diameter (m) B; coil width (m) In the present invention, the following formula may be used instead of the space factor.

LF (t → t + Δt) = 100 × ｛W (t +
Δt) −W (t)｝ / [ρ · {V (t + Δt) −V
(T)｝] where LF (t → t + Δt); casting time t → t + Δt
Instantaneous space factor (%) of the ribbon cast during the period W (t + Δt); coil weight at time t + Δt (t) W (t); coil weight at time t (t) ρ; density of quenched metal ribbon (T / m ³ ) V (t + Δt); Apparent volume of coil at time t + Δt (m ³ ) = π · (Do (t + Δt) ² −Di ² ) · B / 4 V (t); Apparent coil at time t Volume (m ³ ) = π
· (Do (t) ² -Di ² ) · B / 4 Do (t); coil outer diameter at time t (m) Di; coil inner diameter (m) B; coil width (m) It is also possible to measure the winding tension of the quenched metal ribbon and correct the space factor based on the relationship between the winding tension and the space factor determined in advance.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic diagram showing one embodiment of the present invention. In this figure,
1 is a melting furnace for producing a molten metal, and 2 is a tundish in which the molten metal supplied from the melting furnace 1 is temporarily pooled. Reference numeral 3 denotes a nozzle for ejecting the molten metal in the tundish. Reference numeral 4 denotes a cooling roll, which rapidly cools and solidifies the molten metal ejected from the nozzle 3 to form a quenched metal ribbon S. 5
Is a transport conveyor for transporting the quenched metal ribbon S, and is composed of, for example, three stages in series. 6 is two take-up reels 7
It is a carousel reel provided with a and 7b.

Reference numeral 8 denotes a distance sensor such as a laser distance meter or an eddy current distance meter, which measures the distance to the surface of the quenched metal ribbon S wound in a coil shape by the winding reels 7a and 7b. Reference numeral 9 denotes a weight sensor such as a load cell that is attached to the melting furnace 1 and measures the weight of the molten metal.
A space factor measuring device 10 has a function of measuring the space factor of the quenched metal ribbon S by inputting measurement signals from the distance sensor 8 and the weight sensor 9.

The case where the quenched metal ribbon S is wound on the take-up reel 7a will be described below. First, the inner diameter Di (m) of the quenched metal ribbon S at the start of winding on the take-up reel 7a by the distance sensor 8
Is measured. The coil outer diameter Do (m) of the quenched metal ribbon S at the time when the winding is completed by the winding reel 7a is measured by the distance sensor 8 in the same manner. At the same time as the measurement of the coil outer diameter Do (m), the measurement signal from the weight sensor 9 is used to determine the coil weight W (t) of the quenched metal ribbon S wound by the take-up reel 7a. In the space factor measuring device 10, an average space factor LF (hereinafter, referred to as an average space factor) of all the coils using the following equation (2).
Is calculated.

LF = 100 × (W / ρ · V) (2) where: ρ; density of quenched metal ribbon (t / m ³ ) V; apparent volume of coil (m ³ ) ＝ π ・ (Do ² −Di ² ) ・ B /
4B; Coil width (m) In the case of the above equation (2), the equation for calculating the average space factor of the entire coil at the end of winding of the quenched metal ribbon S is expressed by the following equation (3). For example, the occupancy rate for each winding site, that is, for each casting time Δt (hereinafter, referred to as instantaneous occupancy rate) can also be obtained.

LF (t → t + Δt) = 100 × {W (t + Δt) −W (t)} / [ρ · {V (t + Δt) −V (t)}] where (3) , LF (t → t + Δt); casting time t → t + Δt
The instantaneous space factor (%) of the quenched metal ribbon S cast during the period W (t + Δt); coil weight at time t + Δt (t) W (t); coil weight at time t (t) ρ; Band density (t / m ³ ) V (t + Δt); Apparent volume (m ³ ) of coil at time t + Δt = π · (Do (t + Δt) ² −Di ² ) · B / 4 V (t); Apparent volume of coil (m ³ ) = π
・ (Do (t) ² −Di ² ) · B / 4 Do (t); coil outer diameter at time t (m) In the above formulas (2) and (3), both take-up reels When the winding tension changes, the winding tension is measured using a tension meter 11 such as a tension meter roll as shown in FIG. 2, for example. And input to the space factor measuring device 10. As shown in FIG. 3, the space factor measuring device 10 is set in advance to obtain the relationship between the winding tension and the space factor. And
If the average space factor or the instantaneous space factor calculated by the space factor measuring device 10 is corrected based on the measured tension, the average space factor or the instantaneous space factor can be determined more accurately. Can be.

[0014]

Examples: Fe: 80 at%, B: 12 at%, Si: 8 at%
And the molten metal at a temperature of 1330 ° C
A quenched metal strip is jetted out through a 13 mm x 0.8 mm refractory nozzle onto a 850 mm outer diameter water-cooled copper alloy roll that rotates at a peripheral speed of 30 m / sec. It was wound into a coil by a take-up device. The winding tension at this time was 2.4 kgf / mm ² (constant). At that time, the inner and outer diameters of the coil were measured online using an eddy current rangefinder, and the coil weight was measured using a load cell attached to a melting furnace.

Then, the average space factor was calculated by the above formula (2), and the instantaneous space factor at each time was calculated by the above formula (3). In addition, a strip-shaped sample is cut out from the obtained quenched metal ribbon by a conventional method, and the average space factor and the instantaneous space factor (from the roll peripheral speed and the longitudinal position of the quenched metal ribbon at the location where the sample was cut out). Calculation) was measured for each. as a result,
The average space factor of the method of the present invention was 83.4%, which coincided with the average space factor of 85.2% obtained by the conventional method in a range of ± 2%. Also,
The instantaneous space factor obtained by the method of the present invention and the instantaneous space factor obtained by the conventional method were in good agreement as shown in FIG. Furthermore, the characteristic values (correction coefficients) of FIG.
Corrected the average space factor and instantaneous space factor measured online using, the average space factor was 85.1%, which was even more consistent with the measured value by the conventional method. In addition, the instantaneous space factor was more consistent with the measurement result by the conventional method as shown in FIG.

[0016]

As described above, according to the present invention,
The quenched metal ribbon is wound into a coil and its coil weight,
The coil inner diameter and coil outer diameter are measured during and after winding, and the space factor is determined based on the measured values, so that the space factor can be directly and easily evaluated online. is there. In addition, since the instantaneous space factor corresponding to the winding site can be evaluated,
Defective products can also be distinguished.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing one embodiment of the present invention.

FIG. 2 is a schematic diagram showing another embodiment of the present invention.

FIG. 3 is a characteristic diagram showing a relationship between a winding tension and a space factor used in the present invention.

4 (a) is a characteristic diagram showing the relationship between the instantaneous space factor according to the method of the present invention and the instantaneous space factor according to the conventional method, and FIG. FIG. 6 is a characteristic diagram showing a relationship with an instantaneous space factor in a method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Melting furnace 2 Tundish 3 Nozzle 4 Cooling roll 5 Conveyor 6 Carousel reel 7a, 7b Take-up reel 8 Distance sensor 9 Weight sensor 10 Occupancy rate measuring device 11 Tensiometer S Quenched metal strip

Claims (3)

[Claims] When a molten metal is supplied from a nozzle to a surface of a cooling roll rotating at a high speed and rapidly cooled and solidified to produce a rapidly cooled metal ribbon, the rapidly cooled metal ribbon is wound into a coil shape, and its coil weight and coil are used. An online space factor measuring method for a quenched metal ribbon, wherein an inner diameter and an outer diameter of a coil are measured during or after winding, and a space factor is calculated by the following equation based on the measured values. LF = 100 × (W / ρ · V) where LF; average space factor (%) W; coil weight (t) ρ; density of quenched metal ribbon (t / m ³ ) V; apparent volume of coil (m ³ ) = π · (Do ² −Di ² ) · B /
4 Do: coil outer diameter (m) Di: coil inner diameter (m) B: coil width (m) 2. The online space factor measuring method for a quenched metal ribbon according to claim 1, wherein the following formula is used instead of the space factor. LF (t → t + Δt) = 100 × ｛W (t + Δt) −W
(T)｝ / [ρ · {V (t + Δt) −V (t)}] where LF (t → t + Δt); casting time t → t + Δt
Instantaneous space factor (%) of the ribbon cast during the period W (t + Δt); coil weight at time t + Δt (t) W (t); coil weight at time t (t) ρ; density of quenched metal ribbon (T / m ³ ) V (t + Δt); Apparent volume of coil at time t + Δt (m ³ ) = π · (Do (t + Δt) ² −Di ² ) · B / 4 V (t); Apparent coil at time t Volume (m ³ ) = π
・ (Do (t) ² −Di ² ) ・ B / 4Do (t); coil outer diameter at time t (m) Di; coil inner diameter (m) B; coil width (m) 3. The space factor is measured based on a relationship between the winding tension and the space factor determined in advance, the winding force of the quenched metal ribbon being measured. 2. An online space factor measuring method for a quenched metal ribbon according to any one of the above items 2.