US-12623267-B2 - Rolling state observation apparatus and rolling state observation method

US12623267B2US 12623267 B2US12623267 B2US 12623267B2US-12623267-B2

Abstract

Provided are a rolling observation technique whereby the state of rolling on a rolling interface between a material to be processed and a roll can be observed easily and on site; a rolling state observation apparatus for observing the state of rolling at the rolling interface between a material to be processed and a roll during rolling of the material to be processed using two rolls, wherein the two rolls are constituted from a stationary fixed roll and a moving roll that rotates on its own axis while revolving around the fixed roll, and a device for observing the rolling state is provided to the fixed roll; and a rolling state observation apparatus comprising a revolution means for causing the moving roll to revolve around the fixed roll with the center axis of the fixed roll as the rotation center, and a rotation means for causing the moving roll to rotate on its own axis, the rolling state observation apparatus being configured so that the moving roll rotates on its own axis due to the revolution of the moving roll caused by the revolution means.

Inventors

Hiroshi Utsunomiya
Koji Ono
Ryo Matsumoto
Yutaka YABUTA

Assignees

OSAKA UNIVERSITY

Dates

Publication Date: 20260512
Application Date: 20220510
Priority Date: 20210518

Claims (20)

1 . A rolling state observation apparatus for observing a rolling state at the rolling interface between a workpiece and two rolls when the workpiece is rolled using the two rolls, comprising: the two rolls, which are a stationary fixed roll and a moving roll that rotates while revolving around the fixed roll, and a device for observing the rolling state that is provided at the fixed roll.
2 . The rolling state observation apparatus according to claim 1 , which is equipped with a revolving means for revolving the moving roll around the fixed roll with the central axis of the fixed roll as the center of revolution, and a rotating means for rotating the moving roll; and configured to rotate the moving roll by the revolution of the moving roll by the revolution means.
3 . The rolling state observation apparatus according to claim 1 , further comprising a fixed frame to which the fixed roll is fixed and a moving frame to which the moving roll is pivotally supported, wherein the moving frame and the fixed frame makes up the double structure, and the moving frame is rotatably provided around the central axis of the fixed roll, a first gear provided at the rotation center of the moving frame and a second gear provided at the rotation center of the moving roll are arranged so as to mesh with each other, a rotating means for rotating the moving frame and the first gear is provided, the moving roll revolves around the fixed roll in accordance with the rotation of the moving frame, and further the moving roll is configured to rotate by the rotation of the second gear in accordance with the rotation of the first gear that rotates in accordance with the rotation of the moving frame.
4 . The rolling state observation apparatus according to claim 1 , wherein the rotation speed of the moving roll is twice the revolution speed.
5 . The rolling state observation apparatus according to claim 1 , wherein an observation window for measuring the rolling state at the rolling interface between the workpiece and the roll is provided on the peripheral surface of the fixed roll.
6 . The rolling state observation apparatus according to claim 5 , wherein the observation window is formed of a light transmitting material.
7 . The rolling state observation apparatus according to claim 1 , wherein the fixed roll is formed of a light transmitting material.
8 . The rolling state observation apparatus according to claim 6 , wherein the light transmitting material is polycarbonate.
9 . The rolling state observation apparatus according to claim 1 , wherein a cylindrical space is provided in the central portion of the fixed roll, and a reflector is provided at a position directly facing a measurement target portion of the cylindrical space at a 45° inclination with respect to the central axis of the fixed roll, an imaging device for photographing a reflection image reflected by the reflector is provided on an extension line of the central axis of the fixed roll; and the rolling state at the rolling interface between the workpiece and the roll is observed by photographing the surface of the workpiece at the measurement target portion via the reflector using the imaging device.
10 . The rolling state observation apparatus according to claim 1 , wherein a pressure sensor is provided in the fixed roll, and the rolling state at the rolling interface between the workpiece and the roll is observed by measuring the pressure of the lubricant existing at the rolling interface between the workpiece and the roll using the pressure sensor.
11 . The rolling state observation apparatus according to claim 1 , wherein a surface pressure measurement sensor is provided on the surface of the fixed roll, and the rolling state at the rolling interface between the workpiece and the roll is observed by measuring the surface pressure at the rolling interface between the workpiece and the roll using the surface pressure measurement sensor.
12 . The rolling state observation apparatus according to claim 1 , wherein a strain gauge or a displacement meter is provided in the fixed roll, and a stress transmission state at the rolling interface between the workpiece and the roll is observed by measuring the deformation of the roll that occurs during the rolling using the strain gauge or the displacement meter.
13 . A rolling state observation method for observing a rolling state at the rolling interface between the workpiece and the roll when the workpiece is rolled using the rolling state observation apparatus according to claim 1 , wherein the workpiece material is passed through a gap between the moving roll that rotates while revolving around the fixed roll and the fixed roll while supplying a lubricant, and the rolling state at the rolling interface between the workpiece and the roll is observed using a device for observing the rolling state provided in the fixed roll.
14 . A rolling state observation method for observing a rolling state at the rolling interface between the workpiece and the roll when the workpiece is rolled using the rolling status observation apparatus according to claim 3 , wherein the moving roll rotates while revolving around the fixed roll via the first gear and the second gear, by rotating the moving frame using the rotating means, and the rolling state at the rolling interface between the workpiece and the roll is observed by the device for observing the rolling state provided in the fixed roll.
15 . The rolling state observation apparatus according to claim 2 , which comprises a fixed frame to which the fixed roll is fixed and a moving frame to which the moving roll is pivotally supported, wherein the moving frame and the fixed frame makes up the a double structure, and the moving frame is rotatably provided around the central axis of the fixed roll, a first gear provided at the rotation center of the moving frame and a second gear provided at the rotation center of the moving roll are arranged so as to mesh with each other, a rotating means for rotating the moving frame and the first gear is provided, the moving roll revolves around the fixed roll in accordance with the rotation of the moving frame, and further the moving roll is configured to rotate by the rotation of the second gear in accordance with the rotation of the first gear that rotates in accordance with the rotation of the moving frame.
16 . The rolling state observation apparatus according to claim 2 , wherein the rotation speed of the moving roll is twice the revolution speed.
17 . The rolling state observation apparatus according to claim 3 , wherein the rotation speed of the moving roll is twice the revolution speed.
18 . The rolling state observation apparatus according to claim 2 , wherein an observation window for measuring the rolling state at the rolling interface between the workpiece and the roll is provided on the peripheral surface of the fixed roll.
19 . The rolling state observation apparatus according to claim 3 , wherein an observation window for measuring the rolling state at the rolling interface between the workpiece and the roll is provided on the peripheral surface of the fixed roll.
20 . The rolling state observation apparatus according to claim 4 , wherein an observation window for measuring the rolling state at the rolling interface between the workpiece and the roll is provided on the peripheral surface of the fixed roll.

Description

TECHNICAL FIELD The present invention relates to a rolling state observation apparatus and a rolling state observation method. More specifically, a rolling state observation apparatus and a rolling state observation method that enable direct in-situ observation of the workpiece deforming on a rolling interface during rolling processes. BACKGROUND ART Most of the metallic materials such as plates, sheets, strips, foils, bars, rods, wires, sections, pipes, and tubes are industrially manufactured by rolling. Rolling is a bulk metal forming process in which the thickness of the workpiece is reduced to cause elongation while the length increases with passing the gap between a pair of rolls that rotate in opposite directions to each other. The two rolls can continue to rotate without standing still, so that long materials can be processed continuously at high speed. Therefore, the productivity is high. Specifically, as shown in FIG. 10, the workpiece enters the roll bite (roll contact region) at a speed V0 that is slower than the peripheral speed of rolls VR due to the friction forces acting by the rotating rolls, and the thickness decreases from h0 to h1 and elongation occurs before being discharged from the exit of the rolling mill. At this time, the ratio of V1 to VR is called the forward slip (V1/VR−1), and the ratio of V0 to VR is called the backward slip (1−V0/VR). In general, the high friction coefficient between the rolls and the workpiece, results in high forward slip and backward slip. Then, when the workpiece passes through the roll bite, there is a neutral point N where the speed of the workpiece and the peripheral speed of rolls coincide on the way and the relative speed is zero. With this neutral point N as the singularity, the relative speed of the workpiece to the peripheral speed of rolls changes direction, and the direction of the frictional shear stress acting on the rolling interface between the roll and workpiece also changes. For this reason, the deformation of the workpiece on the roll bite and the phenomenon occurring on the interface between the roll and the workpiece are very complicated. It is not easy to elucidate the behavior of the workpiece in the roll bite during rolling. In addition, in rolling processes, lubricants are generally used in order to reduce rolling load and rolling torque and to obtain rolled materials with a smooth surface. That is, the lubricant is usually in liquid state, and by being drawn into the roll bite due to its viscosity and existing as a film under high pressure on the interface between the roll and the workpiece, the frictional shear force acting on the rolling interface between the roll and the workpiece can be reduced. As a result, the rolling load and rolling torque can be reduced, and a rolled material with a smooth surface can be obtained. At this time, in order to make the lubricant function effectively and perform appropriate rolling operations, it is important to appropriately select the type of lubricant, additives and viscosity, as well as the amount and method of supply. The film thickness is theoretically expected to depend on the rotational speed of the rolls and the reduction in thickness. However, since the rolls rotate at high speed and the workpiece passes between the rolls at high speed, it is extremely difficult to observe the lubrication state on the rolling interface, and at present, the film thickness of the lubricant is not measured in situ during processing. Hence, selection of lubricant described above largely depends on experience. In addition, it is not easy to measure the surface pressure and shear stress applied on the roll during rolling. Therefore, it has been proposed that, during conventional rolling, an observation window is provided on the surface of one of the rolls, and the rolling interface during rolling of the aluminum sheet is observed through a reflector installed inside (Patent document 1, Non-patent documents 1 and 2), and that a plasticine sheet made of oil clay is rolled and the rolling interface is observed by installing a camera inside a transparent acrylic roll (Non-Patent Document 3). PRIOR ART DOCUMENTS Patent Documents [Patent document 1] JP 1998-325796 A Non-Patent Documents [Non-patent document 1] “Consideration of Lubricant Behavior by Direct Observation of Plate Rolling Interface”, Hiroshi Ike, Kunio Tsuji, Makoto Takase: Proceedings of 48th Japanese Joint Conference for the Technology of Plasticity (1997), 315-316.[Non-patent document 2] “In situ Observation of a Rolling Interface and Modeling of the Surface Texturing of Rolled Sheets”, H. Ike, K, Tsuji and M. Takase: Wear, 252(2002), 48-62.[Non-patent document 3] “Measurement of Streamlines by Direct Observation of the Surface of Plasticine Rolled Plate using Transparent Rolls”, Kenichi Yasuda: Proceedings of 66th Japanese Joint Conference for the Technology of Plasticity (1997), 345-346. SUMMARY OF INVENTION Problem to be Solved by the Invention