Abstract: A method and device for the automatic detection and evaluation of optical crack indication on the surface of workpieces is disclosed. In such method and device, visual displays are converted into electrical bright-dark signals by the use of light sensitive device, for example, an image recording tube. The surface under observation is scanned by the light-sensitive device line by line, the width of each of which (either as individual line or groups of adjacent lines) corresponds to the maximum optical display width from which evaluation is to proceed. The bright-dark signals thus obtained from three lines or lines groups are compared. From the signal of the middle line or line group and the signals of the two other line or line groups there is formed a difference signal which is evaluated to generate an error evaluation signal of a minimum value is exceeded.

Abstract: The system includes a plurality of individually selectable transmitter and receiver channels, a common controller and a common acquisition unit constructed to operate on the basis of parameters which are furnished to the controller and the unit as input signals. Some of the parameters are held in a memory and are withdrawn on the basis of test identification numbers to set up the acquisition unit. The acquisition unit has a transit time counter and two parallel operating looking window generators and several comparator stages, operating under utilization of such parameters. The data as acquired by a test, are accumulated and processed to determine new parameters, if necessary, and feeding them to the memory. The controller conducts the tests on the basis of sequencing the system through a group of test identification numbers, and provides also launch delay and receiving delays on the basis of externally, updatable parameters.

Abstract: An ultrasonic test system for inspection of structural material includes a test electronics for controlling a plurality of ultrasonic transmitter and receiver channels. This test electronics is operated by sequencing the system through the several channels, but the evaluating circuit is common to the receive channels. The duration of the test, timing of launching, timing of beginning receiving response signals, time and duration of looking windows for identifying and timing particular responses, and comparison data, all are operating and acquisition parameters for operating the electronics. These parameters are furnished from external sources and are programmable and exchangeable, e.g., from test to test. At least some of these parameters are updated on the basis of data as acquired during the test.

Abstract: Ultrasonic echo signals from the rear wall boundary are used to track looking windows for similar signals during a subsequent test cycle as well as for detection of flaw echos, with emphasis on a distinction between end of flaw detection and beginning first rear wall echo looking windows.