|
Vol.2, No1&2, 2002,
pp. 20-22 |
|
RESIDUAL STRENGTH ASSESSMENT OF CRACKED WELDED SPHERICAL STORAGE TANK Todor Adžiev 1 Aleksandar Sedmak 2 Gorgi Adžiev 1 Miodrag Arsić 3 1 Faculty of Mechanical Engineering, University of Skopje, Macedonia 2 Faculty of Mechanical Engineering, University of Belgrade, Yugoslavia 3 GOŠA Institute, Belgrade, Yugoslavia |
|
Abstract Two spherical storage tanks for ammonia (volume 1000 m3) have been tested in 1998 and 1999 by Non-Destructive Techniques (NDT) in accordance with the Periodic Inspection Regulations. These storage tanks have been constructed in 1979 of St.E460 steel according to DIN, Cr-Ni-Ti microalloyed, 30 mm thick. The large number of transverse cracks in weld metal and longitudinal cracks in heat-affected-zone (HAZ) and along fusion line of inner welded joints have been detected. In order to assess the residual strength of both storage tanks, plates 500 x 500 mm were cut for chemical, metallurgical and mechanical testing. These tests included detailed toughness testing of standard Charpy specimens on instrumented pendulum and fracture mechanics testing on standard SEN(B) specimens for fracture toughness evaluation. Based on results of Charpy and fracture mechanics testing residual strength of cracked storage tanks has been assessed. Keywords: instrumented Charpy testing, spherical storage tank, residual strength |
|
full article - only in Serbian (299 kB)
|
