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BULETINUL INSTITUTULUI POLITEHNIC DIN IAŞI
Publicat de
Universitatea Tehnică „Gheorghe Asachi” din Iaşi
Tomul LVI (LX), Fasc. 2, 2010
Secţia
CONSTRUCŢII DE MAŞINI
THEORETICAL AND EXPERIMENTAL CONSIDERATIONS
ON DETERMINING THE EFFECT OF DIVERGENCE
BY
IUSTINA ELENA ROTMAN, PETRU DUSA
and RADU ADRIAN BACIU LUPASCU
Abstract. This paper presents the experimental studies conducted on the basis
of ultrasound examination of the parts with different geometries and structures.
The main objective of this work is to eliminate disturbances in order to perform an
examination and a correct interpretation in case of the A-scan representation. The
experimental results and conclusions drawn follow the analysis of the factors
involved in the process, which negatively influences the interpretation of signals
from the investigation display device.
Key words: transducer, device, back wall, divergence, discontinuity.
1. Introduction
The Ultrasonic Testing Method of materials is practiced by more than 50
years [1], [3].Since the first examination in detecting defects using ultrasonic
oscillations of different materials, it became a classic test method based on
measurements. That method takes in consideration all those factors that have a
certain impact [4]. It is expected that in our days the ultrasonic testing to give
results with minimum tolerance, if that method is sustained by a large variety of
instruments and by one advance technical execution [4].
The structure transformations of the material underlayers by manufacturing
process lead to changes for the workpiece general properties [2]. After the type
of defects are detecting, that will be compared with contractual standard. The
contractual standard would decide if the detected defect could be accepted, not
accepted, or remediable [2]. In many cases some of defects could be accepted if
their values respect standard limits. Once detected the defects types, they must