Blow moulding of thermoplastic containers - with formation of handles and handle recesses in preform during blowing

摘要

Prodn. of thermoplastic containers by blow moulding comprises surrounding a tubular preform with a blow mould in which it is blown by introducing a pressure medium, while simultaneously forming handle recesses and handles. Before introducing the preform into the mould, handles with welding lugs are formed from the preforme in a preliminary separate handle mould. These handles are placed in thrust cartridges belonging to the blow mould, and the cartridges are moved into the blow mould while the preform is introduced in its normal length and expanded. These steps are followed by closure of the blow mould, blowing of the container while welding on the handles, and cooling, while new handles for the next container are formed in the handle mould.