Abstract: A drying and mixing plant for producing a bituminous paving mixture comprises a drying and mixing drum (10) which is supported by a hydraulic cylinder (16) or other lifting means so that the inclination of the drum axis may be altered. By choosing a suitably small angle of inclination so that the drum inclines downwardly towards its outlet end, the plant may be used for continuous operation, so-called drum-mixing. Aggregates and other components may then be supplied continuously to the inlet end of the drum from silos (18), through a center intake (24) from another source (25) and binder such as bitumen may be supplied through a supply tube (58). Finished paving mixture is continuously discharged from the outlet end of the drum and passed to a product silo (28) via a conveyor (27).

Abstract: The invention relates to the technical problem of providing a simple, efficient and easily operable locking mechanism to releasably clamp the bottom ring to the lower edge of the outer mould in a casting mould for the production of concrete or similar pipes in an upright position. With this in view the locking mechanism comprises a radially slotted, resilient locking ring which by means of an opening and closing mechanism is movable between a locking position in which it engages beneath the outer edge portion of the bottom ring and seals said portion tightly against the lower edge of the outer mould, and a free position in which the inner diameter of the locking ring is larger than the outer diameter of the bottom ring so as to enable said locking ring to pass free of the bottom ring when the recently cast pipe is separated from the mould.

Abstract: In a concrete pipe moulding machine comprising a rotationally vibrated core and an outer mould, deficiencies may occur especially in the upper ends of the moulded pipes due to rather vigorous relative movements between the core and the outer mould. Means are provided to moderately reduce these relative movements by neutralizing the tendency of the outer mould to perform a rocking motion caused by the transmission of the rotating vibration forces via the moulding material onto the outer mould.

Abstract: A supporting ring for casting machines for concrete pipes for use in moulding the socket end of the pipe and as a base for the green pipe during the removal of the casting mould and the initial hardening of the concrete, said ring consisting of a hollow annular body of a closed, preferably substantially rectangular cross-section.