Method and instrument for measuring bead cutting shape of electric welded tube
US7236255B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 23, 2003 |
| Grant date | Jun 26, 2007 |
| Priority date | — |
| Expiry date | May 23, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/24
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
To precisely measure bead cutting shapes of electric resistance welded pipes without being affected by difference in luminance level between cut and uncut portions in optical cutting images, an image is obtained by overlaying an optical cutting image with the optical cutting image subjected to thinning processing. A profile of the welded pipe is approximated with a quadratic function and a region containing the bead apex coordinates is identified as the bead. Shape data of the pipe surface at the portion corresponding to the bead portion is obtained from the preset left and right boundaries of the bead portion and the apex position of the separately-calculated bead portion, and bead width, height, slope angle, and unevenness at the left and right boundaries between the bead portion and base pipe portion, are each calculated, based on the left and right bead shape approximation functions and base pipe shape approximation function.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.