Abstract: The invention relates to a mold for producing a T-shaped hose composed of a main hose having a sidewall with an opening and a secondary hose joined at one end to the sidewall opening of the main hose to form a "T". The mold includes a main mandrel for the main hose having a disk-shaped recess on which the main hose is mountable with its opening in registry with the mandrel recess and a secondary mandrel for the secondary hose having a cylindrical recess adjacent to one end thereof. The secondary mandrel is disengageably secured at the one end thereof to the main mandrel adjacent to the recess thereof, so that the mandrels are arranged in the form of a "T" and cooperate with one another to define an interior mold cavity at the zone of connection. The mold further includes an outer mold part that is mountable on the main hose and the secondary hose after each has been mounted on its respective mandrel parts.

Abstract: A process for the manufacture of a circular helix waveguide comprising a helically wound insulated metallic wire covered with a barrier layer and forming a wound and wrapped structure itself covered by a metallic screen, wherein a metal band is shaped into a tube, the contiguous edges of the said band are welded by a high frequency current in such a way that after welding the internal diameter of the shaped tube is a few millimeters greater than the external diameter of the wound and wrapped structure, the said tube is placed around the said structure, then the said tube is shaped into a cylinder with a circular base on the said structure to constitute the said metallic screen.