Abstract: The invention relates to a method of suppressing unwanted indications in automated ultrasonic testing of a test piece.In order to improve the suppression of unwanted indications, in particular in the case of extended statistical suppression, a variable discriminator threshold (3) is derived from the highest of all maximum amplitudes (2) by means of a predetermined amplitude difference (4), wherein the ultrasonic signals are not evaluated as flaw signals when only said variable discriminator threshold (3) is exceeded but are evaluated as flaw signals only when additionally at least the highest of all maximum amplitudes (2) exceeds the fixed discriminator threshold (1) preset for the testing operation.

Abstract: The invention relates to a test head mounting for single or multiple test heads in ultrasonic testing in immersion technique process. To reduce expenditure in the replacement of the test heads, a capacitive coupling is proposed between the test head and mounting element for the test head.

Abstract: A transducer for launching ultrasonic test signals is stimulated by an electrical signal which is of trapezoidal contour. Particularly the trailing edge of the signal is to decline at a rate similar at least as to order of magnitude to the rise time, and occurring in synchronism with a natural zero crossing of the vibration of the transducer to fully develop at least one full ultrasonic oscillation.

Abstract: Equipment for ultrasonic testing structural materials includes transducers and test electronics normally operated in sequential test cycles each cycle including the generation of a test pulse to be sent into the test object and subsequently, upon interaction with the test object, return signals (echos) are received and processed, e.g. as to transit time, amplitude, contour, etc. Self-checking is carried out in three phases. One phase uses simulated receiver signals for operatively disconnected transducers, to be processed by the electronics as if they were echos; a second phase uses simulated transducer inputs and analogous processing and a third phase uses a reference body as test body simulation for conduction of "tests". The results of signal processing are compared with reference signals and correlation of deviations and absence of deviations is used to isolate malfunctions.

Abstract: The test head includes its own calibration device in form of a wire or a bore in front of the transducing surface so that a distinguishable calibration echo is always available.

Abstract: A tubular sleeve with reflector body, water ingress and venting openings is used to produce specific echoes of a test signal launched by an inserted transducer. Amplitude and transit times of the element serve as a transferable standard.

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: 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 transducer is held in a tubular holder which in turn is axially placed in a mount. A frame depends from a cover of a gimbal mounted container for coupler fluid and the mount is clamped to the frame at an adjustable angle so that the transducer axis always intersects the same point. Ball rollers on the cover position the container in relation to a pipe to be tested so that said point is located on the pipe's surface. The transducer holder has a shoulder onto which one may seat a calibration standard.

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.

Abstract: A pipe is reeled onto and over a stand having several positioning rollers to serve as reference for the pipe inspection devices. These devices include a plurality of transducers for longitudinal flaw detection arranged in pairs and along opposite sides of the seam, the transducers being in water tanks hung in gimbals on individual swing arms. Four additional transducers for transverse flaw detection are arranged in a tank hung also in gimbals for positioning the tanks so that it engages the seam while the transducers are aligned with the seam. A gimbal hung tank with two edge probing transducers engages lastly the pipe seam.

Abstract: The initialization and preparation procedure described involves particularly ultrasonic test equipment for ultrasonic inspection of welding seams of pipes while passing through a production line. A dummy is used off line to determine suitable distances and orientation of test heads and to acquire relevant transit time and amplitude data. A standard is then used to obtain additional reference data to be related to the dummy test data. After the test heads are installed in the production line test stand, tests are repeated with the standard to obtain now the needed test reference data in conjunction with the previously related data. This way, looking windows for flaw echos as well as sensitivity data for the subsequent tests are accurately and reproducibly predetermined.