NON-DESTRUCTIVE CONTROL PROCESS AND APPARATUS BASED ON ANALYZING THE PROPAGATION AND ATTENUATION OF ELASTIC WAVES GENERATED BY MEANS OF A MECHANICAL IMPULSE

摘要

The invention relates to a non-destructive control process and apparatus for ferrous, non-ferrous or non-metal products. According to the invention, the non-destructive control process is based on analyzing the propagation and attenuation of elastic waves generated by means of a mechanical impulse produced by a metal ball (5), which strikes, in free fall, a product (1) to be tested and generates therein the longitudinal, transverse and/or surface elastic waves, the elastic waves, which are propagated with various rates, being received by two or more sensors (9) placed on the surface of the product (1), said sensors transmitting electric signals towards a vibration meter (11) with more channels, which register the main sizes that characterize the vibrations, the signals from the vibration meter (11) being taken over by an acquisition plate (12) and transmitted to a computer (13) where they are compared with the signals obtained from the standard flawless products, the computer (13) transmitting the information towards a control interface (14), thus the tested product being marked as qualitatively corresponding or not corresponding. The non-destructive control apparatus used for applying the process, consists of a percussion system made as a guiding tube (7), wherethrough a ferro-magnetic ball (5) falls freely, strikes a product (1) to be tested, then lifting and being retained by a magnet (8) positionable on the vertical, avoiding a second impact upon the product (1), placed on a support (2), placed, in its turn, on a phono-absorbing damping plate (4), the support (2) being provided with positionable and height-adjustable supports (3), and on the surface of the product (1) there being placed two or more sensors (9), by means of some springs (10), the signals collected by the sensors (9) being taken over by a vibration meter (11) which transmits the collected signals towards a computer (13) and therefrom towards a control interface (14) in order to mark the product.