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Manufacturing of ionizing radiation source Ir-192 activity 50100 Ci has been begun that 20-30 pieces of disks of natural iridium (=2.7 mm, h=0.2 mm, m=31.7 mg) was placed in aluminum foil packing, then aluminum container with packaging in vertical channel of the WWR-SM reactor was irradiated by neutrons at following regime: special container EK-10 with iridium disks loading place is into core of fuel assemble type IRT-4M on distance 3045 cm from top point of fuel assemble; nominal power of reactor =10 МWt; reactor operating mode with periodic stopdowns; thermal neutrons stream density ≥0,7×1014 n/сm2sec; irradiation time ≥550 hours. Than after certain exposure aluminum packaging with disks of iridium irradiated containing Ir-192 radionuclide to special device was placed and their radiochemical processing was spent. Then iridium disks irradiated in stainless steel capsule (=4.5 mm, h=8.0 mm) was placed, by cover was closed, dot argon-arc welding was spent and check of tightness of Ir-192 sources by immersion method was spent. The dimensions of the active part of the source are =3.0 mm, h=4.0 mm.
For complete set gamma flaw detector of Gammarid 192/120М with source of Ir-192 in the special installation source of Ir-192 was placed in the source holder, closed by cover and rolling was spent, source holder with source of Ir-192 with flexible shaft was connected and to gamma flow defector of Gammarid 192/120М protective radiating head was charged. Then Ir-192 source together with gamma flow detector of Gammarid 192/120М for carrying out of gamma-radiographic NDT method of pipelines welded seams of quality assurance was used.
Non-destructive testing was carried out using source of Ir-192 of welded seams of metal designs and pipelines and gamma-radiography x-ray pictures was received (Figure 1). By NDT method with Ir-192 sources received x-ray images in terms of sensitivity and quality was corresponded to requirements of Russian standards (GOST-7512-82 «Control nondestructive control. Connections welded. Radiographic method») and USA standards (ASME).
Figure 1. X-ray picture of welded seam sample (=50.8 mm) received
by ionizing radiation source of Ir-192.