IIW History 1948-1958

140 -

-

the present state of its welds that a decision is taken as to the future of such a construction . Below are some results achieved in some clearly determined applications.

a) a Belgian investigation on the relationship between the density of a porou \Yeld, determined by radiography, and its fatigue behaviour (r ); b) an Italian study on the same subject (2); c) an American study on the relationship between the mechanical properties and radiographs of welds in aluminium carried out by arc welding in inert atmosphere (3); d) British research work on the relationship between the fatigue behaviour of welded steel pipes subjected to pulsating pressures or free bending and the appearance of the radiographs (4); e) observations on the brittle fracture of a welded vessel in relation to its inspection by radiography (5). The programme of work which Commission V has drawn up includes : a) critical study of the t ypes of ultrasonic apparatus and methods for defining thei r uses ; b) systematic research on the behaviour of ultrasonics in the presence of different types of welJ Llefects. Interpretation of the signal given by the apparatus (6). A study on the geometric factors connected with the \veld and the ultra– sonic beams emitted, reflected or deflected has been begun. Experiments concerned with the visual reading of ultrasonics have been begun in Belgi um (7); c) establishment of a multilingual collection of terms in use in ultrasonic inspection (8); d) calibrati on of radiographic apparatus (9); e) recommended practice for the radiographic examination of circumferen– tial butt welds in pipes (9); f) acceptance criteria for the quality of welds in pressure vessels and boilers (9) in liaison with Commis~ion X I (Pressure vessels, boilers and pipe lines) ; g) acceptance criteria for the quality of the radiographic image in the case of pressure vessels and boilers (9); h) tests for checking the quality of radiographic films (9) ; (1) (Copenhagen, August 1949 and Goteborg 1952.) (2) (Document XIII-65-55.) (3) (Oxford 1951.) (4) (Goteborg 1952, Copenhagen 1953 and Florence 1954 : report of lvfr. Nmnu~, B"WRA, "nited Kingdom) . (5) (Zurich 1955.) (6) (Annual report Essen 1957.) (7) (See Annual report Oxford 195 r .) (8) (Document V-23-57-0E.) (9) (Essen 1957.) 4. PRESENT AND FUTURE WORK.