Abstract: A welding system of cylindrical structures which welds a welding end surface of an upper cylindrical structure and that of a lower one in an axial direction thereof, includes: two or more welding apparatuses opposite to the welding end surfaces and disposed at equal arrangement intervals in the circumferential direction thereof; a moving device configured to rotate the upper and lower cylindrical structures relative to the welding apparatuses in a circumferential direction thereof; and a control device configured to control the welding apparatuses and the moving device. The welding apparatus has a filler metal and a heating source therefor, and melts and fuses the filler metal on the welding end surfaces to weld them, and the control device is configured to continuously rotate the upper and lower cylindrical structures an angle of the arrangement interval by the moving device, while welding the welding end surfaces with the welding apparatuses.

Abstract: A welding camera (1) is constructed with: a lens (11) for focusing incident light; an optical filter (12) that comprises a neutral density filter for reducing the amount of the incident light, an ultraviolet cut filter for cutting ultraviolet rays, and a green band-pass filter for transmitting green light; a CMOS imaging unit (13) that has a wide dynamic range function, and detects the light which has passed the optical filter (12); a video signal processing unit (14) that has an automatic gain control function and a digital signal processor, and outputs an image signal, which covers a range of a low-intensity dark part to high-intensity arc light, to a display unit on the basis of an electric signal that is input from the CMOS imaging unit (13).

Abstract: A welding camera (1) is constructed with: a lens (11) for focusing incident light; an optical filter (12) that comprises a neutral density filter for reducing the amount of the incident light, an ultraviolet cut filter for cutting ultraviolet rays, and a green band-pass filter for transmitting green light; a CMOS imaging unit (13) that has a wide dynamic range function, and detects the light which has passed the optical filter (12); a video signal processing unit (14) that has an automatic gain control function and a digital signal processor, and outputs an image signal, which covers a range of a low-intensity dark part to high-intensity arc light, to a display unit on the basis of an electric signal that is input from the CMOS imaging unit (13).