Blow mold for the manufacture of containers made of thermoplastic material

摘要

A blow mold for making PET containers comprising an inner surface corresponding to the outer outline of the container, on which there are one or more cavities or projections configured to make corresponding respective projections or cavities of the outer surface of the container, wherein the mold comprises one or more venting grooves along the edge delimiting said cavities or projections. A plurality of venting holes are possibly arranged along such grooves, as well as it is also possible for some venting holes to be arranged outside thereof. The width and depth of these are selected according to the wall thickness of the container to be blown to prevent that the deformation of the container during the blowing obstructs the venting grooves and leaves visible marks on the container.