Method and apparatus for detecting flaws in strip, method of manufacturing cold-rolled steel sheet and pickling equipment for hot-rolled steel strip
US6266983A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 23, 1999 |
| Grant date | Jul 31, 2001 |
| Priority date | — |
| Expiry date | Nov 23, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/2626
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A flaw detecting method and apparatus for continuously testing a strip that is continuously carried through a liquid includes features for reducing air bubble generation in a liquid. The apparatus includes a liquid, carrying rolls for passage of the strip through the liquid, and ultrasonic testing probes arranged in the liquid for testing the strip. A carrying roll in contact with the liquid is fully immersed. Air bubble generation is inhibited to improve the testing reliability by at least one of (a) shielding the liquid dropping from the portion of the strip leaving the liquid, (b) reducing the dropping force of the liquid onto the liquid surface by inclining the strip, (c) installing the fully immersed carrying roll at a depth of at least 5 mm in the liquid, and (d) using a carrying speed of less than about 200 m/min. Upon manufacturing steel strips, testing is carried out in the stage of hot-rolled steel sheet, or, preferably, in pickling equipment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.