Constructability Suggestions for Flowline, Flowline Jumper (FJ) & PLET

Asked by davidnivola 5 years, 3 months ago | 1 Answers

1 Answer

Habib Ramini 5 years, 3 months ago
  • Need to identify stabilization period for flexible and rigid jumper combination for hydrotest.
  • Identify plan to dewater pipeline, specifically gas injection (define dryness criteria). Need to define who handles this task.
  • Consider flexible pipe for entire length of flowline. Consider material compatibility (e.g. MEOH), pigging, reliability, insulation, etc.
  • Consider elimination of gauge pigging after installation of flowline. Check current code for applicability. That would need alternate method to verify no kinks in line.
  • Prepare plan for safe anchoring for future field projects.
  • Consider testing pig-able "y" with the pigs that will be used.
  • Consider definition of functional requirement for insulation. Need qualification criteria for insulation and thermal analysis. The Risk of not meeting a performance spec. has cost implications.
  • Flowlines need to be isolated from compliant tower.  Supply Insulation kit for cathodic protection.
  • Make sure there is enough contingency in minimum bend radius for flow line and umbilical installation.
  • Gather temperature data of sea bottom during hazard survey to validate insulation system design.
  • Ensure there is test data on riser available for review.
  • Define acceptable condition that flowlines will be left by contractor.
  • Define acceptable specification for reel lay installation alternative. Make sure minimum requirements associated with each installation method are identified.
  • Need Long BaseLine (LBL) array for accurate positioning of PLET. Alternate is Ultra Short BaseLine (USBL), precision is better with LBL.
  • Use positioning array installed for positioning tower; fixed frame with removable Compatt Transponder, or, field wide acoustic system.
  • Ensure length of flexible FJ meets length required to overcome torsional stiffness. Use mock-up of connection points to verify fit-up.
  • Consider rigid well jumpers in lieu of flexible jumpers. Ensure metrology is proper.
  • Introduce more bend in flow line to take care of thermal growth, simplify PLET design.
  • Consider allowing entire PLET to move relative to seabed vs. fixed with sliding piece. Less weight, can use winged mud mats.
  • Ensure inline tee(s) remain in correct orientation.
  • Confirm dimension of inline tee is compatible with stinger. Design of ITA and PLET are handled by contractor.  Need to have a good functional specification to maintain reasonable control.

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