Advances in forming machine technology & processes have been accompanied by similar, yet comparatively less heralded, advances in forehearth technology. For modern forming processes, the rejection rate and the requirements for faster machine speed are inherently linked to thermal homogeneity levels in the gob and, by extension, to the efficiency of the forehearth conditioning system. The Emhart book of glass container defects lists some 63 ware faults of which 53 can be attributed to the forehearth. Though many of these defects are multicausal, the potential impact on pack-rate from a poorly designed and inefficient forehearth is clear. Forehearth induced container defects are usually associated with glass thermal homogeneity & temperature stability & these in turn are determined by the efficiency of the forehearth & its associated subsystems.
