Is it necessary to install a downhole safety valve in a subsea ... - NTNU

Is it necessary to install a downhole safety valve in a subsea oil/gas well?
Prepare for running completion.
Make up 7” double and rack back same.
Make up and run bottom of tubing completion assemblies.
Run tubing to DHSV depth.
Run in hole production PBR on drill pipe for space-out.
Close BOP and mark drill pipe.
Pull drill pipe out of hole.
Make up DHSV assembly.
Test control lines.
Run remaining tubing accessory to final space out
9) Run tubing hanger
Make up tubing hanger to tubing.
Connect control lines to tubing hanger. Install tubing hanger in center.
Make up tubing hanger running tool to tubing hanger
Run tubing hanger on drill pipe.
Land and lock tubing hanger to the x-mas tree.
Open downhole supply valves DS1-DS4.
Engage electric stab and hydraulic system.
Close middle pipe ram.
Pressure test tubing hanger gallery seals, DHSV control lines and tubing hanger.
Spot high viscosity mud across tubing hanger.
Unlatch tubing hanger running tool. Pull out of hole with tubing hanger running tool on
drill pipe.
10) Pull tubing hanger isolation sleeve
Pull tubing hanger isolation sleeve on 0.125” slick line through the marine riser.
11) Run workover riser
Run tree cap, tree cap running tool, electric stab assembly, workover riser and surface
tree w/45 ft bails
Land and lock tree cap.
12) Set prod packer
Displace well to diesel, drop ball to seal off tubing side.
Pressure up tubing to set production packer
Inflow test DHSV. Test production packer. Function test LBV and OBV
13) Pull Pre installed production packer
Rig up wire line and run in hole. Pull pre-installed production packer setting plug
14) Flow well
Flow well to test plant.
Rig up wireline production logging tool.
Log and flow well.
15) Test and abandonment of well
Shut in and inflow test DHSV.
Pump MEG on top of DHSV
Rig up tubing hanger crown plug.
Diploma thesis, NTNU 2002
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