Provision of Review, Support and Comparative Fracture Assessment for HSS Welds

The contract will be to

• support ONR’s review of the fracture assessment benchmarking document which provides WEC responses to the EASL review comments relating to the WEC approach for dissimilar metal welds completed in Step 4, providing comments on their validity, scope, key assumptions, and compliance with good practice as appropriate;
• support ONR’s review of the fracture assessment benchmarking document which provides comments on the WEC responses to the results of the EASL comparative fracture assessments completed in Step4, providing comments on their validity, scope, key assumptions, and compliance with good practice as appropriate;
• Undertake additional comparative calculations for a sample of at least 2 of the updated fracture assessments for HSS welds. The depth and breadth of the sample will be informed by the insights gained from the outcome of the review of the WEC responses to the comparative calculations completed at Step 4 i.e. the review of the benchmarking report. The sample is expected to include a HSS weld where fatigue crack growth is important.
• Provide written reports covering the work above, with appropriate explanation and justification for the comments, along with an appropriate hierarchy of their significance for ONR’s consideration.
• Provide support to ONR in technical meetings with the RP. These meetings will be either ‘face to face’ in the UK (Liverpool or Chorley) or by video conference (v/c) at the ONR Office in Liverpool. The number of meetings will depend on the progress of the reviews, but for planning purposes two ½ day ‘face to face’ meetings and 9 off ½ day v/c meetings should be assumed.
• Support ONR if appropriate on the drafting of queries and/or observations to request additional information for the RP and advise on the adequacy of the RP’s responses.
• This work must be completed within the timescale of the GDA Step 4 close-out for the UK AP1000 so as to inform the ONR position on the adequacy of the RP’s safety case. The review of the benchmarking report is scheduled to complete by end of September 2015 and the review of a sample of the fracture assessments for the HSS welds (which may include welds in the RPV, pressuriser, SG or other HSS components) is scheduled for completion in mid-July 2016.