15 Operations Procedures
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Transcript of 15 Operations Procedures
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Operations ProceduresOperations Procedures
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
ContentContent Operations ProceduresOperations Procedures
• Gravel Packing• Installing Completion String• Other Stimulation/
Completion Requirements• Kicking -off Well and Cleanup
Flow• Post Completion
- Well Surveillance
• Objectives of Well Completion Operations
• Phases of Well Completion Operations
• Pre-Completion- Drilling, Running Casing/
Liners and Cementing• Well Cleaning• Perforation
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Objectives of Well Completion OperationsObjectives of Well Completion Operations
Operations ProceduresOperations Procedures
What is a successful well completion operations ???
• To complete a well that meet reservoir, production, production technology, surveillance, safety and cost requirements
• Reservoir : Maximise recovery from the field or target sands• Production : Maximize long term production rates (P.I.)• Production Technology : Zero formation damage, control sand
production, completion integrity (i.e. mechanical, corrosion, pressure, downhole conditions), high P.I., meet AOF
• Surveillance : Meet welltest, PLT, pressure / temperature survey, sampling, zone selectivity, etc. needs as required
• Safety : Safe operations and safe well (now and future)• Cost : Within planned cost
A successful well completion operation meets these objectives asrequired
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Phases of Well Completion OperationsPhases of Well Completion Operations
Operations ProceduresOperations Procedures
Well completion operations start from the time the hydrocarbonzone of interest is drilled to the period of initial production todetermine if completion objectives are met• Pre-Completion
- Drilling, Running Casing / Liners and Cementing - Retrieving old completion
• Well Cleaning• Perforation• Gravel Packing• Installing Completion String• Other Stimulation / Requirements• Kicking-off Well and Cleanup Flow• Post Completion
- Well Surveillance
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Pre-Completion - Drilling, Running Casing / Liners, Pre-Completion - Drilling, Running Casing / Liners, Cementing and Pulling Old CompletionCementing and Pulling Old Completion
Operations ProceduresOperations Procedures
The objective during is to minimise or prevent formation damagefrom any activities affecting the formation by :
• minimum overbalance• compatible drilling fluids• minimum damaging solids in drilling fluids• for openhole completion
- drill-in fluids to prevent losses- breaker solution to clean mud-cake after setting pre-drilled/
slotted liners • keep hole in size to minimise cement sheath to be perforated• minimise losses into the formation • to kill well for re-completion, use clean fluid
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Well CleaningWell Cleaning
Operations ProceduresOperations Procedures
Objective is to have clean completion fluid in the well prior toperforation and running completion :
• Clean all surface fluid system (tank, pipings, return lines, etc.) and work string prior to commencing well clean up
• After cementing, RIH with bit and scrapper to clean out casing, clean well and displace well to completion fluids
• Circulate two well volume while scrapping and drilling to remove any cement scale or cuttings until well is clean
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Well Cleaning (cont..)Well Cleaning (cont..)
Operations ProceduresOperations Procedures
• Displace mud out of the well and replace with seawater by pumping cocktail of :- 50 bbl base oil (if oil based mud used)- 20 - 50 bbl hi-vis (Guar gum or HEC) spacer- 100 - 150 bbl wash pill (Super Pickle 3 % w/v)- 100 - 150 bbl flocculant pill (Dirt Magnet 3 % w/v)- 20 - 50 bbl hi-vis spacer (Guar gum or HEC) spacer- sea water
• Circulate and dump after base oil is returned• Continue circulating at highest possible rates while dumping
returns sea water until NTU reading of 30 to 40• Repeat cocktail if required (i.e. if returns is still dirty)• After seawater returns are cleaned, displace well to completion
brine. Monitor returns to ensure brine is cleaned and weight as required.
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
PerforationPerforation
Operations ProceduresOperations Procedures
Objective is to perforate safely and maximise productivity
Procedures depend on the type of perforating methods :Retrievable Tubing Conveyed Perforation• Run guns on pipe. Set underbalance from cushion• Correlate depth with GR. Set retrievable packer.• Fire gun (drop bar, internal or annulus pressure)• Flow well until cushion or oil to surface• Kill well and POOHWireline Conveyed Perforation (Casing Guns)• RIH casing guns in wireline• Correlate depth with CCL• Fire gun with current from surface• Observe well. POOH
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Gravel PackingGravel Packing
Operations ProceduresOperations Procedures
• After well in cleaned, perforate zone with RTCP underbalance• Set sump packer on wireline• RIH gravel pack assembly (screen, top packer and gravel pack
tool) on drill pipes• Sting in bottom packer and set top packer• Establish 4 position (squeeze, lower circulation, upper
circulation and reverse) with gravel pack tool• Establish injectivity• Perform acid job if required• With tool in lower circulating position, circulate down gravel
slurry until screen out• Reverse out excess gravel from the work string• Recheck screen out• Perform acid wash as required• POOH
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Installing Completion StringInstalling Completion String
Operations ProceduresOperations Procedures
• Make up completion string as per planned design• Pressure test each completion accessory and completion
string as required• Make-up and test SCSSSV and control line• Sting into permanent packer (if used) and space-out string• Make up tubing hanger and land string• In multilateral well GR correlation run may be required for
dual completion• Set hydraulic packer
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Installing Completion String (cont..)Installing Completion String (cont..)
Operations ProceduresOperations Procedures
• Running pre-packed screen• Horizontal sand control
- screens- gravel pack
• Running Electrical Submersible Pump (ESP)• Multilateral completion• Openhole completion• Openhole gravel pack• Running cement evaluation tools - normally after well
cleaning
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Other Stimulation / Completion RequirementsOther Stimulation / Completion Requirements
Operations ProceduresOperations Procedures
Detailed procedures must be work out with the servicecompanies for any work to be carried out e.g. :
• Hydraulic Fracturing• Resin sand consolidation• Acidisation• Through Tubing Perforation• Integrated Tubing Conveyed Perforation (ITCP)
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Other Stimulation / Completion Requirements Other Stimulation / Completion Requirements (cont..)(cont..)
Operations ProceduresOperations Procedures
• Running pre-packed screen• Horizontal sand control
- screens- gravel pack
• Running Electrical Submersible Pump (ESP)• Multilateral completion• Openhole completion• Openhole gravel pack• Running cement evaluation tools - normally after
well cleaning
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Kicking-off Well and Cleanup FlowKicking-off Well and Cleanup Flow
Operations ProceduresOperations Procedures
• Well can be kickoff by either :- Displacing the tubing string to a lighter fluids e.g.
diesel or fresh water- Artificial lift e.g. gas lift
• Flow should be initiated at a low drawdown (i.e. low choke for natural flowing well) to prevent fines movement which can create wellbore damage and possible gas / water coning
• Choke up well gradually• Cleanup flow is the flow period during which completion
fluids, mud filtrate, gel and other "external" fluids are flowed out of the formation and well
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Kicking-off Well and Cleanup Flow (cont..)Kicking-off Well and Cleanup Flow (cont..)
Operations ProceduresOperations Procedures
• Cleanup flow can take a few hours to one month or longer depending on the well productivity, amount of fluid lost and volume below packer
• True well performance in not known until well is cleaned up• Where practical well should be put under test during
cleanup with all parameters (FWHP, BSW, rates, GOR, etc.) measured
• All completed zones to be cleanup as early as possible as "external" fluids in contact with the formation may create damage over time
PE Skill Group 10
BASIC WELL COMPLETION
May 2003
Well SurveillanceWell Surveillance
Operations ProceduresOperations Procedures
• Keep well under close surveillance during cleanup flow and initial production to determine if objectives are met
• All surface parameters (FWHP, FWHT, BSW, density) to be monitored closely if well cannot be out on test at all time
• Perform IPR / VFP analysis using the latest data to determine productivity
• Carry out bottom hole pressure surveys (reservoir and flowing) as soon as possible after well is cleaned-up
• Perform PBU survey to determine skin if production is below expectation