B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
B29C53/00—Shaping by bending, folding, twisting, straightening or flattening; Apparatus therefor
B29C53/36—Bending and joining, e.g. for making hollow articles
B29C53/38—Bending and joining, e.g. for making hollow articles by bending sheets or strips at right angles to the longitudinal axis of the article being formed and joining the edges
B29C53/48—Bending and joining, e.g. for making hollow articles by bending sheets or strips at right angles to the longitudinal axis of the article being formed and joining the edges for articles of indefinite length, i.e. bending a strip progressively
B—PERFORMING OPERATIONS; TRANSPORTING
B31—MAKING ARTICLES OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER; WORKING PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
B31F—MECHANICAL WORKING OR DEFORMATION OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER
B31F1/00—Mechanical deformation without removing material, e.g. in combination with laminating
B31F1/0003—Shaping by bending, folding, twisting, straightening, flattening or rim-rolling; Shaping by bending, folding or rim-rolling combined with joining; Apparatus therefor
B31F1/0045—Bending or folding combined with joining
B31F1/0048—Bending plates, sheets or webs at right angles to the axis of the article being formed and joining the edges