Molding method for making a monolithic component internally provided with at least one cavity inside

A molding method for making a monolithic component internally including at least one cavity, comprising the following steps:

• providing that the monolithic component internally including the at least one cavity is made of C-SMC;
• providing a press comprising a first half mold and a second half mold, with one between the first half mold and the second half mold being a movable half mold and the other between the first half mold and the second half mold being a stationary half mold, the first half mold and the second half mold defining between them a molding space, the press also comprising movable side carriages acting in conjunction with the first half mold and the second half mold to define the molding space;
• providing an oil circuit containing oil and configured for using the oil to move the movable half mold to open and close the molding space;
• placing at least one core inside the molding space, wherein the core comprises a membrane, the membrane delimiting a containing space which is shaped to form the at least one cavity of the monolithic component, and at least one connector engaged with the membrane and configured to allow filling the containing space;
• wrapping a charge of material to be molded around the core so that the core is at least partly immersed in the charge of material;
• fixing the core inside the stationary half mold;
• filling the containing space of the membrane with a filling material through the connector;
• after closing the first half mold and the second half mold using the oil from the oil circuit, applying a molding pressure on the charge of material to form the monolithic component;
• and, after these steps,
• emptying the containing space of the filling material;
• after opening the first half mold and the second half mold using the oil from the oil circuit, removing the core from the molded monolithic component;
• in the step of filling the containing space of the membrane, placing the containing space in fluid communication with a delivery section of the oil circuit to create a feed flow of a predetermined quantity of the oil from the oil circuit to the containing space, the predetermined quantity of oil acting as the filling material for the containing space, and/or in the step of emptying the containing space, placing the containing space in fluid communication with a return section of the oil circuit to create a return flow whereby the predetermined quantity of oil, acting as the filling material for the containing space, flows back from the containing space to the oil circuit;
• providing that the membrane has, on an exterior of the containing space, a smooth, polished surface.