Method of determining warp status for corrugated board

A warp determination method for a corrugated fiberboard manufacturing device, which determines warp statuses of a plurality of corrugated fiberboard one box outs, respectively, in the corrugated fiberboard manufacturing device, the corrugated fiberboard manufacturing device longitudinally cutting a corrugated fiberboard web conveyed in a sheet conveyance direction by a slitter scorer to form a plurality of corrugated fiberboard one box outs, transversely cutting the plurality of corrugated fiberboard one box outs in a sheet width direction, respectively, by a cutoff, and then, stacking the plurality of corrugated fiberboard one box outs on a sheet stacking unit of a stacker, the warp determination method comprising:

• measuring displacement values of the plurality of corrugated fiberboard one box outs downstream of the slitter scorer in the sheet conveyance direction and upstream of the sheet stacking unit in the sheet conveyance direction;
• dividing a measurement range according to a width dimension that is a dimension of the plurality of corrugated fiberboard one box outs in the sheet width direction;
• allocating the divided measurement ranges to the plurality of corrugated fiberboard one box outs, respectively;
• and
• determining warp statuses of the corrugated fiberboard one box outs for each of the plurality of corrugated fiberboard one box outs, on the basis of the displacement values in the allocated measurement ranges.