IIW History 1948-1958

134 -

-

d) Tl1e possibilities offered by radio-isotopes for the inspection of welded assemblies have been the subj ect of various contributions to the work of the Commission; these have dealt in particula r with the sphere> of application in relation to the nature of the radio-active elements used . e) The use of the B etatron for the inspection of welds has been the subj ect of cooperative reports (r) which have shown that this t echnique is useful in the case of very thick materials. / ) After several years of collective research , Commission V gave its agree– ment to the p ui)lication , by a Dutch organisati on, of a booklet entitled I nvesti– gatio11 Oil the Influence of the Thickness of a Bu.tt n·eld , the oiwce of Rad·iat·ion, the i\llethod of Exposu.re and the Positi on of the I nhom ogeneities on the k adiograpMc I mage and of a Comparison of the R ep1·esentatwn on Different T y pes of I mage Qu.at?"ty Indicators (2) . g) Another work , p repared by the members of Commission V under the direction of Dr lVIORAVIA (Italy), will shortly appear. It will be published in different member countries of the IIvV, being a document recommended by the Institute for publication . Thi work is entitled H andbook on Radi ograph£c A pparatu.s and T echni qite (3). h) A document entitled R ecommended Practice for the R adiographic I nspec– tion of F ·itsion welded Joints for Steel Plates itp to 2 ·inches ( 50 mm) has been prepared and \Yil! be published in the majority of national 'Nelding revie\YS (4) . i) S ince r 95r, the Commis ion has recommended an increase in the value of de nsity, generally accepted by tho e concerned, for rad iographic films . j ) It has also recommended the use of films size 3" x ro " (75 mm x 255 mm) (5)- The Commission has, since 1950, been trying t o est ab lish t o what ext ent t ests fo r the qualification of welders cou ld be simplified as a result of the judicious use of radiographic inspection . Tests \Yere carried out for several years by taking radiographs and examining the appearance of fractures in welds. It appeared that, once a welder had been certified, the relationship between the behaviour of hi s welds a nd their radiographic aspect was such that the periodical qualifi– cati on t est s undergone by welders could be simplified a nd considerable weight could be given t o properly conducted radiographic exami nations. In 1956, a report (6) jointly adopted by Commissions \ and XIV « Welding Instruction » was recommended for publication. Its title is Recommendation regard1:ng the preparat?'on of rules f01' the qualification of welders. This document is of a ge neral character a nd has been suppl emented by appendices which are being discussed and conside red jointly by the two Commissions mentioned above. 2° Qualification of Welders.

(1) D r 0. \ -At: PEL, Gernw.ny , Copenh agen Assembly 1953; Dr H . ::llor,u-:R, Germany, Florence Assembly 195-1, Doc. \ ' -5-5-1-0P.

(2) (Essen Assem bly 1957, Doc. \ '-S-57-0E.) (3) (Essen Assembly 1957 ; Doc. Y--1-5 7-0E.) (4) (Document Y- 6-5 7, E ssen Assembh· 1957.) (5) (Oxford Assembly t951 .) (6) (Document \ --3-56.)