Measuring and testing – Specimen stress or strain – or testing by stress or strain...
Patent
1988-06-10
1989-12-26
Myracle, Jerry W.
Measuring and testing
Specimen stress or strain, or testing by stress or strain...
73159, G01N 300
Patent
active
048889938
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a non-contact type apparatus for the measurement of a reduction ratio during the rolling of a steel sheet or the like.
BACKGROUND ART
The reduction ratio of a rolled material can be computed from the speed of movement of the material before and after the rolling. As a means for measuring the speeds of movement of the material before and after the rolling, a contact type apparatus was often adopted in which measuring rolls or other measuring devices were brought in contact with strip coils on the inlet and outlet sides. However, recently, since the rolling speed has greatly increased and the necessity for a wet rolling using water or oil because of high-pressure operation has increased, the problem of a reduction of the measurement precision due to slip page has become serious, and therefore, a non-contact type apparatus in which magnetic marks are formed on the inlet and outlet sides and these marks are inspected in a non-contact manner has been developed. Apparatuses of this type are disclosed in Japanese Examined Utility Model No. 43-29667 and Japanese Unexamined Patent Publication No. 55-94711.
Japanese Examined Utility Model Publication No. 43-29667 discloses a basic apparatus in which the speed of movement of a magnetic mark on a material is measured before or after rolling. However, this apparatus is defective in that, when the material is moved at a high speed, a delay in operation occurs in either a magnetizer or a detector and an offset error inherent to the rolling operation cannot be avoided. As a means for overcoming this defect, the applicant of the instant application developed and proposed the measurement apparatus disclosed in Japanese Unexamined Patent Publication No. 55-94711. However, when this apparatus was put to practical use, it was found that this apparatus still leaves problems to be solved. Namely, in the actual rolling operation, since the material has a property such that the hardness on the inlet side is lower than the hardness on the outlet side, the intensity of the magnetic mark is proportionally reduced, and an erroneous operation is readily caused by noise, especially in the case of a soft material such as low-carbon steel for use in deep drawing, for which the demand has recently increased. Moreover, since the material on the inlet side is softer than on the outlet side and local deformation is readily caused by the winding motion of the roll through its travel, the gap, between the material and the detector is changed, which generates noise and worsens the S/N ratio, and in this case, of the comparison level of the detector is fixed, the error in the detection is enlarged.
It is an object of the present invention to provide a measurement apparatus in which the problems of the apparatus disclosed in Japanese Unexamined Patent Publication No. 55-94711 are solved and the reduction ratio can be precisely measured irrespective of the kind of material to be rolled.
SUMMARY OF THE INVENTION
The object of the present invention is attained by an apparatus for measuring the reduction ratio of a rolled material, which comprises magnetizers disposed on the inlet and outlet sides of a rolling mill to form a magnetic mark on a material to be rolled and detectors coupled with the magnetizers and spaced from the corresponding magnetizers by a certain distance, wherein the reduction ratio is computed from the speed of movement of the material on the inlet and outlet sides, the apparatus being characterized in that the apparatus further comprises a gate which is opened by a detection signal from the detector on the outlet side and is closed after an optimum time determined by the line speed and the set range of the reduction ratio, the rising of the signal after sampling of the logical product of the gate signal and the detection signal on the inlet side is adopted as the timing for detection of the magnetic mark on the inlet side, and between the respective coupled magnetizers and detectors on the inlet and outlet sides, the magnitu
Inoue Tadashi
Takahashi Toyoki
Tsutsui Kiyomi
Yamaoka Masayoshi
Myracle Jerry W.
Nippon Steel Corporation
LandOfFree
Apparatus for measuring reduction ratio of rolled material does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus for measuring reduction ratio of rolled material, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for measuring reduction ratio of rolled material will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1572075