Abstract: An inspection track is scarfed by moving a burner across a flat surface of a steel slab, particularly a slab of ductile steel of deep-drawing quality, to enable sub-surface inspection of the slab. To achieve accurate control of the depth of the track, the burner is mounted on a burner carriage having at least one skid surface which contacts the slab surface of the slab at an unscarfed region thereof. A guide track is spaced from the slab surface and the carriage is moved with said skid making sliding contact with the slab surface while guided by said guide track. The skid surface makes substantial contact pressure with the slab surface so that scale on the slab surface is pushed aside and/or crushed by the skid surface, whereby the burner is maintained at a substantially constant distance from the slab surface.

Abstract: Marking apparatus especially for applying identifying marks to large coils, has a base 26 which is reciprocatingly moved along a track past the surface to be marked. Mounted on the base, so as to be movable transversely with respect to the base's movement, is a marking carriage 30 carrying marking means 36,37. In order to increase the area which can be marked and in particular to apply two lines of text, the carriage is mounted on the base by means of at least two spaced apart swivelling arms 29 which form an articulated quadrilateral such that the carriage is movable transversely between two limit positions with respect to the path of movement of the base.

Abstract: The problem of loss of strength in carboard along a line of fold due to stretching and breaking of fibres on the outside of the fold is overcome by providing a machine having a support surface against which the sheet of cardboard which is to be folded is held by an element which has a knife edge. The support surface is provided by a taut flexible sheet material which extends around a rotatable and movable roller. On operation of the machine, the roller is moved around the knife edge, its longitudinal axis being kept parallel to the knife edge, thereby making a fold in the sheet and the cardboard. The flexible sheet which contacts the cardboard has a high coefficient of friction with respect to cardboard. The restrains the cardboard fibres on the outerside of the cardboard as the fold is made preventing their stretching and breaking and thereby providing an unweakened fold.

Abstract: Injection of steam into the ascension pipe of each coking chamber in a coking plant is continued for a period of time after charging of that chamber so as to create a slightly sub-atmospheric pressure in the chamber during the initial stage of the coking process, in order to reduce leakage of gas and fumes to the atmosphere past the doors and filling openings. A time clock operated by the coke pusher machine or by the coal charging machine stops this injection of steam after a desired period of time.