Abstract: A building structure for recurrent detonation of explosive charges of up to several hundreds of kilos with the aim to obtain effective sound dampening and economical use of materials.The building comprises a tube shaped steel structure (2) with two gable walls (4,4) inside the tube and which defines an explosion chamber (6) in the center portion thereof. One or preferably both of said two gable walls are apertured by a plurality of through-going openings. A webbed wall or the like (20) is situated at least in one end portion of the tube which together with respective adjacent gable wall (4) defines one, respectively two, gable chambers (16) which are filled with a mass of stones (18) or the like. The tube shaped steel structure is positioned horizontally and freely resting on a sand bed (36) or the like and is covered along its entire length with sand (38). The building is effective to obtain a sound dampened gas discharge and a pressure relief.

Abstract: Apparatus for so-called "in-line" production of hollow articles of thermoplastic material, by blowing or vacuum moulding a sheet strip produced continuously from an extruder and subsequent stamping of the separate articles. The mould tool consists of at least two mould half portions, which is moved along a rectilinear guide and substantially synchronously with the plastic strip. The guide for the mould tool and the direction of the sheet strip extend obliquely downwardly from the extruder nozzle, preferably at an angle to the horizontal plane of 30.degree.-60.degree. . In the zone of the guide path where the mould half portions open, stationary gripping fingers are arranged on both sides of the sheet strip. The fingers are adapted to engage the longitudinal edges of the sheet strip immediately prior to the mould half portions, being separated and to absorb the sheet strip while the mould tool returns for enclosure of a new portion of sheet strip.