Abstract: Production of hollow shaped bodies made of pourable and hardenable material, particularly polyurethane tires, in a mold cavity having a deformable membrane. The membrane is expanded to fill the mold cavity and expel air therein. Thereafter an amount of material required to produce the shaped body is introduced into the mold cavity and concomitantly the membrane is contracted to the form of the core. This minimizes air bubbles in the shaped body. A piston-cylinder unit movable with the inflow and outflow of liquid to the deformable membrane may be used to accurately control feed of polyurethane material to the mold cavity.
Abstract: Production of hollow shaped bodies made of pourable and hardenable material, particularly polyurethane tires, in a mold cavity having a deformable membrane. The membrane is expanded to fill the mold cavity and expel air therein. Thereafter an amount of material required to produce the shaped body is introduced into the mold cavity and concomitantly the membrane is contracted to the form of the core. This minimizes air bubbles in the shaped body. A piston-cylinder unit movable with the inflow and outflow of liquid to the deformable membrane may be used to accurately control feed of polyurethane material to the mold cavity.