Objective RECENTLY COMPLETED PROGRAMMES HAVE CONFIRMED THAT THE APPROACH TO THE ASSESSMENT OF THE SAFETY OF WELDED JOINTS BASED UPON THE COD TEST AND THE USE OF THE BURDEKIN AND DAWES DESIGN CURVE GIVES RELIABLE PREDICTIONS OF DEFECT TOLERANCE WHEN CORRECTLY USED. THIS WORK HAS, HOWEVER, CONCENTRATED UPON BS 4360 GRADE 50 TYPE STRUCTURAL STEELS (OR THEIR EQUIVALENT) WHICH HAVE BEEN SHOWN TO POSSESS VERY GOOD FRACTURE TOUGHNESS AND THE FRACTURE PROCESS IN THE PARENT METAL, THE WELD METAL AND HEAT AFFECTED ZONE (HAZ) HAS USUALLY BEEN BY DUCTILE PROCESSES AT TEMPERATURES EQUIVALENT TO THOSE EXPERIENCED DURING SERVICE. MORE RECENTLY, HOWEVER, STEELMAKERS HAVE PRODUCED A RANGE OF MICRO-ALLOYED LOWER CARBON STRUCTURAL STEELS FROM CONTINUOUSLY CAST FEEDSTOCK. THIS PRODUCTION PROCESS RESULTS IN SOME DEGREE OF CENTRE LINE ALLOY SEGREGATION WHICH IS LIKELY TO HAVE A SIGNIFICANT INFLUENCE ON THE FRACTURE TOUGHNESS IN PARTICULAR IN THE HEAT AFFECTED ZONE. IT IS NECESSARY, THEREFORE, TO CONFIRM THE ADEQUACY OF THESE STEELS AND TO PROVIDE GUIDANCE ON WELDING PROCEDURES AND HAZ TOUGHNESS REQUIREMENTS TO ENSURE AVOIDANCE OF FRACTURE. IN ADDITION, HIGHER STRENGTH STEELS ARE NOW BEING MORE WIDELY USED IN PROCESS PLANT AND OFFSHORE STRUCTURAL APPLICATIONS. THESE STEELS WILL INEVITABLY EXHIBIT LESS DUCTILITY PRIOR TO FRACTURE. IT IS POSSIBLE THAT THE FAILURE CONDITION IN THESE CIRCUMSTANCES MAY BE ACHIEVED PRIOR TO THE ATTAINMENT OF A GENERAL YIELDING CONDITION IN THE WIDE PLATE TEST AT TEMPERATURES CLOSE TO THE MINIMUM DESIGN TEMPERATURE. THIS IS PARTICULARLY LIKELY WHEN FATIGUE CRACKS ARE LOCATED IN THE WELD METAL OR HEAT AFFECTED ZONE OF THESE HIGHER STRENGTH STEELS. IT IS, THEREFORE, PROPOSED TO STUDY THE INFLUENCE OF SEGREGATION ON THE SIGNIFICANCE OF DEFECTS IN WELDS IN LOW CARBON GRADE 50 TYPE AND A HIGHER STRENGTH STRUCTURAL STEEL, USING COD AND WIDE PLATE TESTS TO EXTEND THE USE OF THE BURDEKIN AND DAWES APPROACH TO THE ASSESSMENT OF THE SAFETY OF WELDED JOINTS IN THESE SITUATIONS. Programme(s) ECSC-STEELRES 6C - Medium-term orientation (ECSC) "steel research in relation to the General Objectives for Steel", 1981-1985 Topic(s) Data not available Call for proposal Data not available Funding Scheme Data not available Coordinator Swinden Technological Centre EU contribution No data Address Moorgate S60 3AR ROTHERHAM United Kingdom See on map Total cost No data
