OTL performed the compliant piled tower (CPT) pre-feed study at water depth of 330 m, including complete in-place and pre-service analyses, miscellaneous calculations and the whole-set of structural and installation drawings. The work evidences that CPT concept in general is valid for application in South China Sea with water depth 330 m and deeper.
Client: CNOOC
Date of Started: 12/20/2018
Location: South China Sea: Water depth of 330 m
Topside Weight: Max. 27500 MT
SOW: OTL performed following studies and analyses, and submitted associate reports
· In-service compliant tower (CPT) platform information investigation
· Drilling/ Completion Operation & Procedure
· Topside Design Optimization suggestion
· Structural Design and analyses
o In-place nonlinear time domain strength analysis
o In-place time history fatigue analysis
o Wearing analysis
o Foundation pile installation, free standing, and pile drivability analysis
o Interim- construction condition nonlinear time domain strength analysis
o For pre-service conditions, loadout analysis , transportation marine and structure analysis, launch marine and structure analysis, flotation/upending marine analysis
· Miscellaneous calculations, such as ViV, cathodoic protection design, hydrostatic ring design, launch cradle design, and grouted connection strength calculations.
· Schedule Planning for Construction and Installation
· Feasibility analysis of CPT application in the South China Sea
· CPT FEED design work scope and requirement, specifications.
Extral work performed included:
· Provided concept design for leveling pile template, pile installation template, leveling piles;
· Performed installation feasibility study for 1-section CPT;
· Provided critical concept design for installation from OSI: selections of gripper, leveling jack, and grout packer;
· Transportation time domain analysis, check CPT lift-up under slamming loads;
· Optimization CPT configuration design: traditional 12-leg CPT to optimized 8-leg CPT