Assembly lines, namely, a series of machines and lines composed thereof for the production and processing of steel; rolling mills for use in metalworking; tubing mills for use in metalworking; slab sizing press; electric welding machines; laser welding machines; friction stir welding machines

flatness testing machines and instruments; automatic pressure control machines and instruments; automatic liquid-flow control machines and instruments; automatic temperature control machines and instruments; automatic combustion control machines and instruments; electric meters; magnetic object detectors; computer programs for use in controlling automatic gauge control machines, automatic shape control machines, automatic flatness control machines, automatic pressure control machines, automatic liquid flow control machines, automatic fluid composition control machines, automatic temperature control machines, automatic combustion control machines