Abstract: A heat exchanger comprising a large number of flexible individual elements, has supply and discharge devices for the heat exchanger media and also has, for these elements, tension devices which expand during heating. The tensioning of the individual elements, which are adhesively bonded at each of their two ends into slots of end plates, takes place by the application of the required forces to the end plates. A heat exchanger of this type is illustrated in FIG. 1.

Abstract: A method for making parallelepiped or brick-shaped containers of greater mechanical strength and better appearance, avoiding any mismatching of the printed patterns due to displaced joints in the middle of the side of the container walls. A longitudinal seal is positioned at the corners rather than on the face of the side walls, thus leaving the side walls without joints or splices. A packaging material web taped coated with thermoplastic material and provided with folding lines is twisted when passing through two bending rollers and one slack-absorbing roller and is converted into a cylindrical shaped and then sealed at the overlapping side edges. The cylindrical container is then filled with a liquid through a filler pipe and sealed at predetermined intervals.

Abstract: A blank for packing containers having a carrier layer of paper or cardboard and a layer of thermoplastic-coated aluminum foil which is used for generating by means of induction devices the heat required for sealing overlapping plastic layers of the blank in a Z-shaped configuration wherein the aluminum foil layer is removed locally along the sealing regions in outer layers but is kept intact in the inner layer.

Abstract: The invention relates to a material for packing containers comprising punched out blanks or a coherent web made up of a carrier layer of cardboard which on either side has a coating of thermoplastics. The carrier layer is reduced in thickness along selectively chosen regions in that parts of the carrier layer material are ground away and the regions of the blank or of the web which include the said thickness-reduced regions are folded over one another so as to form a so-called Z-fold wherein parts folded together are sealed to one another in order to form portions of rigid form, the total material thickness within the said ground portions of the Z-folded region A substantially corresponding to the thickness of the non-ground material.

Abstract: A method for thinning a web along selected regions of a blank or a web of a material having at least one layer of paper or cardboard by passing the material over one or more die rolls, each being provided with raised portions which bring the material into contact with a rapidly rotating grinding wheel which grinds which selected surfaces of the material away.