Abstract: A universal mold carrier for use in a mold assembly compensates for parting forces associated with container formation by directing a compensating air flow pressure to the rear surface of the mold carrier. The mold carrier includes two mold halves adapted to matingly engage each other and hold within the mold carriers interchangeable mold shells. One of the mold carriers has an outside wall that has a plurality of independent air flow compensating surface areas located thereon. This mold carrier further has an air flow communication line interconnecting the independent air flow compensating surface areas. Shut off valves are located in the one carrier to close and to open the air flow communication line between adjacent independent air flow compensating surface areas to allow for adjustment of the compensating pressure.

Abstract: A base assembly for use as a part of a mold assembly for making containers comprises an adaptor, a base insert (or base plug), and a wear ring. The base insert is made from aluminum and has a lower surface positioned on a flat upper supporting surface of the adaptor. The base insert has an upper surface with a ledge surrounding a recessed contoured pattern in the base insert Which pattern corresponds to a base of the container to be formed. The base insert has an annular side wall portion. The wear ring has an inner annular surface surrounding and engaging the annular side wall portion of the base insert to protect the annular side wall portion. The wear ring comprises a hardened wear resistant steel ring adapted to reinforce the base insert during formation of the container. The base insert and wear ring are secured to the adaptor by threaded fasteners that pass through threaded apertures in the adaptor, the base insert and the wear ring.