Abstract: In the method and the apparatus for measuring and controlling the roll gap in a roll stand the roll gap is illuminated by a light source transversely of the roll axis or also parallel to the roll axis. A camera, in particular a CCD line camera, is aligned with its optical system with the roll gap and the illuminated part of the gap is broken down in this camera in the direction of the height or thickness of the gap into image points which generate on illumination an electrical charge, the image points being consecutively periodically interrogated for bright-dark information by drive electronics and the sum of the bright or dark light points serving as information on the magnitude of the roll gap and for controlling the roll gap setting.

Abstract: To determine the thickness profile of rolled metal sheets by measuring the absorption of X-rays a slit diaphragm is used which is rotatable about the imaginary center axis of the X-ray tube, the rotation consisting of a reciprocating movement lying in a range of less than 36.degree.. Between the reversal points of the rotation the rotational movement takes place in steps with rest intervals lying therebetween.

Abstract: A method for the continuous, quasi-static and contactless determination of the width of hot rolled products within a rolling mill train, preferably of hot wide band, via diode line cameras on which the two side edges of the illuminated rolling mill product are projected. The position of the illuminated edges of the rolling mill product is measured by alternating-current fed lamps in successive measuring cycles of 10 msec. Immediately following the exposure, the resulting electrical charge on the diodes within a measuring cycle in a period of 200 usec used, is scanned (sampled). Scanning is always at the maximum of intensity of illumination of the lamps. The electrical charge on the diodes for facing edges may be simultaneous, and the bright-dark transitions of the projected edges may be detected in the diode lines. The diodes darkened by the rolled product are counted in the diode lines above the two edges.

Abstract: A method and an apparatus are disclosed for equalizing the temperature of hot steel strip traveling from a preliminary rolling mill to a final rolling mill, equalization to be effected both lengthwise and transversely of the steel strip. To achieve this purpose the lateral edge portions of the steel strip are partially covered by heat reflectors which are spaced from and adjustable relative to them.

Abstract: An apparatus for non-destructively testing materials by ultrasound and eddy current, which includes an ultrasound material testing device operating in conformity with the electrodynamic converter principle, and also includes an eddy current material testing device. The testing coils of both testing devices are centrally arranged with regard to each other in such a way that the workpiece regions controlled by the testing coils have an at least approximately common central axis. The apparatus furthermore includes a control device which in conformity with the energization of the coil for creating the strong magnetic field for operation of the electrodynamic converter is operable briefly alternately respectively to turn-on and turn-off the respective testing coil of the ultrasound and eddy current material testing device.

Abstract: A method of and device for ultrasonically checking a workpiece while employing an electrodynamic sound converter including a checking head and a coil adapted to be energized to create a magnetic field, according to which during the checking operation the workpiece in a continuous movement relatively is passed by the testing or checking head of the electrodynamic sound converter. The coil for generating the magnetic field is energized by an alternating current or an intermittent or alternating direct current. Furthermore, the electrodynamic sound converter in conformity with the intensity of the magnetization of the coil is switched on and off in such a way that a sound converter is switched on when the magnetization has reached a predetermined value, and is switched off as soon as the magnetization drops below another predetermined value.

Abstract: A device for checking materials by means of an electrodynamic converter which includes a magnet and at least one high frequency coil arranged between the core of the magnet and the workpiece. The high frequency coil includes a first section effective with regard to the generation of ultra sound, and a second section which is not effective with regard to the generation of ultra sound. In the first section the individual currents in the windings of the high frequency coil have approximately the same direction while the second section is located outside the magnetic field of the magnet or opposite the workpiece behind a shielding.

Abstract: An arrangement for measuring the flatness or planar degree of metal strips under tensile stress while being rolled, in which measuring rollers are subdivided into roller sections. Measuring elements which may be in the form of strain gages, are held in suspensions having side members which are pivotable about a fixed axis. The side members also support the individual roller sections of the measuring rollers. The measuring elements or strain gages may be fixed in the roller bearings linking the suspension and the measuring rollers. The measuring elements may also be located in a recess of the side members. Each roller section may be provided with a measuring element, and the side members, furthermore, may be connected by rigid joints to a shaft which is reinforced by a rigid box and about which the side members are pivotable. The side members, moreover, may be T-shaped and be hinged to the rigid box, while being force-linked to a cover plate containing a recess for the measuring element.