Heating preforms

A method for reheating and conditioning an elongate preform for forming a blow moulded container, wherein said preform is formed from a thermoplastic material and has an outer surface, the method comprising the steps of:

• i) discontinuously contacting the outer surface of the preform with a surface of a receiver, wherein the surface of the receiver includes an elongate annular non-cylindrical inner surface portion which is rotationally continuous about an elongate axis and provides a three-dimensional relief adapted to engage in substantially non-uniform contact with said outer surface of the preform, and said receiver is adapted to transfer heat conductively from said surface of the receiver to the preform;
• and
• ii) heating the receiver such that heat is transferred conductively from the receiver to the preform;
• wherein the three-dimensional relief provides a relief depth of 0.5 to 1.0 mm;
• wherein the three-dimensional relief is adapted to provide contact and non-contact areas between the elongate annular inner surface portion and the preform;
• and wherein the contact areas are provided by raised parts of the three-dimensional relief and the non-contact areas are provided by recessed parts of the three-dimensional relief.