Abstract: A landing mat for compacted terrain is formed by assembling a multiplicity of mat elements in contiguous relationship. Each of these elements has a rectangular plan configuration and is formed along its longitudinal edges with downwardly bent flanges, and between these flanges, with flattened corrugations forming longitudinal ribs perpendicular to the planar upper surface of the element. Stabilizing plates can extend transversely to the ribs and flanges and can have upwardly open slots snugly receiving the ribs. Clips bridging contiguous edges of adjoining elements are fitted into elongated windows spaced inwardly of these edges to hold the elements together and an edge member, likewise having a flattened-corrugation rib, is fixed along one edge of the mat and has downwardly turned tongues fitted into the window of the elements along the latter edge.

Abstract: A rail mounting system for mounting ties on concrete rails includes one or more concrete rails each having an upper surface from which a passage extends inwardly and downwardly and diverges in downward direction. For each passage there is provided a rail mounting member having a shaft provided at its upper end with a springy portion and at its lower end with a claw which extends laterally of and is inclined to the shaft. The upper open end of the passage has an outline corresponding to a vertical projection of the claw onto the surface of the tie.

Abstract: An electrodynamic sound converter is disclosed for the non-destructive ultrasonic testing of workpieces during relative movement of the workpiece and the testing head. The testing head has an annular electromagnet which produces a magnetic field, and a rod-shaped core extends coaxially through the electromagnet and has a tip which projects beyond the same in direction towards the workpiece to be tested. The core is axially slidable relative to the electromagnet towards and away from the workpiece and the electromagnet and the tip of the core are each independently maintained at a fixed predetermined spacing from a surface of the workpiece being tested. The tip is being biased towards the surface, and a high-frequency coil is located adjacent the tip and serves to produce electromagnetic oscillations. Various modifications are also disclosed.

Abstract: A cooling element for a metallurgical furnace in which a body of cast material has cooling tubes and adapted to face the interior or the furnace and is transversely spaced opposite marginal portions. The marginal portions of the cooling element are provided with alternating tooth-like configuration having teeth and tooth gaps between them. The cooling tubes or pipes have two inlet planes and two outlet planes. The inlet ends of the cooling pipes are alternately located in one inlet plane and in the other inlet plane and are alternately located in the one outlet plane and the second outlet plane.

Abstract: To apply indicia to a surface of a traveling workpiece, particularly of a rapidly moving workpiece, a beam of coherent laser light is split to form two rays, one of which is deflected directly onto the surface whereas the other is indirectly guided onto the surface. The two rays form on the surface two parallel indicia which are located opposite one another but are spaced transversely of the direction of workpiece movement.