moulding without guide pins according to the present invention consisting of a metal frame 14 which supports the other component elements a slide of the surface of the mobile press 1 on which there is in turn fixed the mobile half mould 3 a support for the surface of the fixed press 2 on which there is in turn fixed the non movable half mould 4 and a transporting device defined hereinafter also as force plug carrying bar 10 driven by a force plug carrier movement device 12 which is more clearly visible in fig4 a the following description refers to an embodiment with a single moulding cavity but it is clearly applicable to the case of moulds with a number of cavities set side by side the mobile slide 1 of the surface of the press sliding along its guides performs the travel of approach and recession of the mobile half mould 3 with respect to the fixed half mould 4 which is connected in an integral way or preferably in a sliding way to the surface of the fixed press 2 i e the surface of closing and opening of the mould as a whole according to a basic characteristic of the present invention the two half moulds are kept in a closed position by a tie rod provided with a hammer shaped head which is gripped by closing jaws 6 and in the following description is defined as tie rod for closing a device which opposes the internal pressure of injection moulding that would tend to open up the half moulds the moulding cavity of the mould is defined in addition by one or more internal force plugs 11 a plurality.