A SYSTEM AND A METHOD FOR PROVIDING IONISED AIR TO EXTRUSION BLOW MOLDED WEB MATERIALS, AND A CUTTER FOR CUTTING A TUBE SHAPED EXTRUSION BLOW MOLDED WEB INTO TWO OR MORE WEBS

摘要

A web processing method and apparatus for processing a tube shaped web material (16) into one or more sheets (18, 19), e.g. two sheets, of the web material which are forwarded through the apparatus in parallel. The apparatus comprises means (3, 11) for introducing pressurised ionised air into the area between two essentially parallel and opposing surfaces of the web material. The means for introducing ionised pressurised air are integrated into the body part (3) of an edge slitting knife, preferably made of a polymer, such as homo or copolymers of PET, PET-P, HD-PE, PP, PEEK, PSU or mixtures thereof onto which an air ioniser (11) based on AC or pulsed DC technology is connected to a pressurised air inlet (1) of the knife body for ionising the air to be passed to the air nozzles (6) of the knife body (3). Alternatively an ionising air bar (20) is applied between two sheets of web (18, 19). Reduced wear on the knife body part (3) is obtained and electrostatic effects acting on surfaces of the web (16, 18,19) facing each other is neutralised or controlled in order to reduce the tendency of the web to cling to apparatus parts and/or to itself or to the other web sheet.