Abstract: A machine for crystallizing a thermoplastic preform or container is constructed from modular subassemblies and utilizes a preheated plug to provide the sole upright support for a workpiece in the crystallizing process. The first modular subassembly includes the workpiece in-feed and plug preheat structures and incorporates the drive apparatus for the entire machine. The opposed end of the crystallizing machine is constructed of a subassembly which operates to provide the turnaround and tensioning takeup for the carrier mechanism transporting the workpieces. Positioned between the first subassembly and the opposed end subassembly are heating and cooling processing modules which can be provided in any number depending on the size constraints and workpiece quantity restraints desired. The processing modules provide the heating and crystallizing processes for the desired area of the workpiece and the cooling process of the workpiece prior to unloading.