Abstract: A mold system has a hollow outer mold part extending along a mold axis, a hollow inner mold part inside the outer mold part and forming therewith an elongated cup-shaped cavity adapted to hold a plastic mass for the production of a preform, and a cooling tube extending coaxially inside the hollow inner part and forming a passage having an inner portion inside the tube and an annular-section outer portion outside the tube and between an outer surface of the tube and an inner surface of the inner mold part. A cooler circulates a coolant fluid through the passage. A plurality of angularly spaced and generally axially extending support ribs extend radially from one of the surfaces toward the other surface in the outer passage portion.

Abstract: A mold system has a hollow outer mold part extending along a mold axis, a hollow inner mold part inside the outer mold part and forming therewith an elongated cup-shaped cavity adapted to hold a plastic mass for the production of a preform, and a cooling tube extending coaxially inside the hollow inner part and forming a passage having an inner portion inside the tube and an annular-section outer portion outside the tube and between an outer surface of the tube and an inner surface of the inner mold part. A cooler circulates a coolant fluid through the passage, A plurality of angularly spaced and generally axially extending support ribs extend radially from one of the surfaces toward the other surface in the outer passage portion.