US 12,459,023 B2
Welding monitoring apparatus and welding monitoring method
Noboru Hasegawa, Tokyo (JP); Michitoshi Tanimoto, Tokyo (JP); and Michimasa Mukai, Tokyo (JP)
Assigned to NIPPON STEEL CORPORATION, Tokyo (JP)
Filed by NIPPON STEEL CORPORATION, Tokyo (JP)
Filed on Aug. 25, 2023, as Appl. No. 18/456,314.
Application 18/456,314 is a division of application No. 16/331,067, abandoned, previously published as PCT/JP2016/083135, filed on Nov. 8, 2016.
Prior Publication US 2024/0082900 A1, Mar. 14, 2024
Int. Cl. B21C 51/00 (2006.01); B21C 37/08 (2006.01); B23K 11/06 (2006.01); B23K 11/087 (2006.01); B23K 11/25 (2006.01); B23K 13/02 (2006.01); B23K 13/08 (2006.01); B23K 31/00 (2006.01); B23K 31/12 (2006.01); G01N 21/892 (2006.01); G01N 21/952 (2006.01); G01N 29/04 (2006.01)
CPC B21C 51/00 (2013.01) [B21C 37/08 (2013.01); B21C 37/0818 (2013.01); B23K 11/062 (2013.01); B23K 11/0873 (2013.01); B23K 11/252 (2013.01); B23K 13/02 (2013.01); B23K 13/08 (2013.01); B23K 31/003 (2013.01); B23K 31/125 (2013.01); G01N 21/892 (2013.01); G01N 21/952 (2013.01); G01N 29/041 (2013.01); G01N 29/043 (2013.01); G01N 2291/267 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A welding monitoring method for monitoring welding of a V-convergence region in which a strip-shaped metal sheet is converged in a V-shape, when the metal sheet is cylindrically formed while being conveyed in a longitudinal direction, and both side edges of the metal sheet are heated and melted in a manner of being butted each other while being converged in the V-shape, such that an electric resistance welded steel pipe is manufactured, the method comprising:
an image capturing step of capturing images from above a region including the V-convergence region in a plan view in time series; and
a detecting step of extracting a welding point based on the images captured from above in time series and detecting the presence or absence and a position of irregular arcing at the welding point or on an upstream side of the welding point,
wherein RGB images are used as the images, and
wherein in the detecting step,
at least one of a red image and a blue image is extracted from the RGB images,
inverted binarization and labeling of the red image are performed with respect to the red image, and
a high-luminance portion in the blue image is detected with respect to the blue image.