EEMUA Publication Construction specification for fixed offshore structures

Transcription

1 Contents Preface... iv Principal changes in the 3 rd Edition Introduction and objectives Scope Definitions Abbreviations Units Glossary of technical terms References Quality assurance and safety Quality Assurance Health, safety and environmental issues Welding engineers Welding coordinators Welding inspectors Materials Weldable structural materials Welding consumables Miscellaneous materials Bolts, nuts and washers Castings and forgings Materials substitution Materials handling Receipt of materials Maintenance of identity Storage conditions Qualification of welding procedures and personnel General requirements Approval process for welding procedures Initial submission Procedure qualification records Submission of the qualification package Restrictions on welding practices Welding procedure qualification tests General requirements Types of test weld Inspection and NDT requirements and acceptance criteria Mechanical testing requirements and acceptance criteria Failed procedures Essential variables Materials related variables Weld geometry related variables Consumables and equipment variables Procedural variables Welding parameter variables Qualification of welding personnel Existing qualifications v

2 4.6.3 Categories of qualification and testing requirements Re-testing Requalification Qualification test records Construction General requirements Preparation and assembly Handling procedures Efficient use of free issue materials Spacing of seams and splices Design of welded connections Forming and straightening Edge preparation Alignment and fit-up of welded joints Rat-holes, penetrations and cut-outs Control of production welding Welding environment Welding consumables and equipment Preheat and interpass temperature requirements Temporary and non-structural attachments, ancillaries and miscellaneous steelwork Weld execution Weld interruptions Weld repairs Welding restrictions on PWHT items Weld profile, surface finish and clean-up Production controls Post Weld Heat Treatment (PWHT) Welds requiring PWHT PWHT procedures Certification Bolted connections General Bolting details Piles and followers Fabrication tolerances General Local tolerances for structural components and sub-assemblies Fabricated tubulars and cones Rectangular plated sections Cruciform joints Joint misalignment Global tolerances for the completed structure Jacket and deck node work points Final alignment of bracings and jacket legs Appurtenances Padeyes, padears and lifting trunnions Miscellaneous structural steelwork tolerances Handrails Deck plating, walkways, stairways and landings Openings/penetrations Pile length vi

3 7 Inspection and non-destructive testing General Inspection and NDT Extent of inspection and NDT Timing of final inspection and NDT Qualification of inspection and NDT procedures and personnel Non-destructive testing procedures Qualification of inspection and NDT personnel Non-destructive testing techniques Visual inspection Ultrasonic testing Radiography Magnetic particle inspection Leak testing Acceptance criteria for flaws General Visual acceptance Ultrasonic acceptance Radiographic acceptance Magnetic particle examination acceptance References Bibliography Appendix: CTOD testing of HAZs for welding procedure qualification A1 Introduction A2 Testing requirements A2.1 Number of tests A2.2 Specimen preparation A2.3 Testing A2.4 Procedure for validation A2.5 Reporting A2.6 Acceptance criteria and retesting vii

4 List of Figures Figure 1 Example of a welding procedure specification Figure 2 Example of a site welding instruction sheet for semi-automatic and manual welding Figure 3 Example of a PQR mechanical test report Figure 4 Demonstration piece for T, K and Y joints Figure 5 Examples of acceptable weld profiles for tubular intersections Figure 6 Hardness indentation locations for grout bead procedures Figure 7 All weld tensile test piece locations Figure 8 Locations of indents for hardness surveys Figure 9 Locations and notch positions for weld metal/haz Charpy specimens.. 37 Figure 10 Charpy Specimen locations for weld repairs Figure 11 Location of Charpy specimens in punch-through weld Figure 12 CTOD Test piece geometries and notch locations Figure 13 Welder test piece for single sided welds Figure 14 Welder test piece for special applications Figure 15 Prohibited areas for node barrel and stub welds Figure 16 Circumferential tolerance Figure 17 Ovality tolerence Figure 18 Procedure for determination of out-of-circularity Figure 19 Out-of-circularity tolerance Figure 20 Out-of-roundness tolerance Figure 21 Local straightness tolerance for tubulars Figure 22 End perpendicularity tolerance Figure 23 Node barrel and stub lengths Figure 24 Out of straightness tolerance for members Figure 25 Node stub location Figure 26 Node and tube stiffener locations Figure 27 Ring stiffener cross section tolerances Figure 28 Out-of-straightness tolerance for stiffeners in tubulars Figure 29 Plate girder cross section tolerances Figure 30 Plate girder out-of-straightness tolerance Figure 31 Plate girder stiffener tolerances Figure 32 Box girder tolerances Figure 33 Girder node lengths Figure 34 Tolerances for stiffened plate panels Figure 35 Joint mismatch tolerance Figure 36 Global positioning tolerance for tubular nodes Figure 37 Tolerances for stab-in node mating surfaces Figure 38 Pile sleeves positioning tolerances Figure 39 Conductor guides positioning tolerances Figure 40 Caisson and J-tube guides and riser clamps positioning tolerances Figure A1 Illustration of GCHAZ location relative to the weld beads Figure A2 Sketch micro-map of microstructures and grain sizes in HAZ Figure A3 Illustration of idealised CTOD notch line Figure A4 Idealised straight-line micro-map of HAZ Figure A5 Details of notch placement for notched CTOD specimen Figure A6 Details of notch placement for surface notched CTOD specimen Figure A7 Details of post-test sectioning for through thickness specimens Figure A8 Micro-map showing microstructures and grain sizes Figure A9 Details of post-test sectioning for surface notched specimens viii

5 List of Tables Table 1 Welding consumables and recommended lot classifications Table 2 Requirements for extent and type of inspection and NDT Table 3 Types and number of mechanical tests required for WPQ Table 4 Weld metal and HAZ Charpy test requirements Table 5 Recommended inspection/ndt categories Table 6 Allowable ovality Table 7 Checking positions for ovality and O of R tolerance Table 8 Ovality measuring positions Table 9 Procedure for determination of out-of-circularity Table 10 Tolerances for plate girders Table 11 Tolerances for plate girder stiffeners Table 12 Box girder tolerances Table 13 Tolerances of stiffened plate panels Table 14 Visual inspection acceptance criteria Table 15 Ultrasonic testing acceptance criteria ix