Pr 1047 well integrity maintenance

Petroleum Development Oman L.L.C.
Well Engineering
Well Integrity Maintenance
Procedure
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RESTRICTED Document ID: PR-1047
May 2007 Filing Key: Business Control
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Revision: 2.0
Effective: May2007
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Revision: 2.0
Effective: May 2007 Petroleum Development Oman LLC
i Document Authorisation
Authorised For Issue: May 2007
Printed 21/05/07 PR-1047, Well Integrity Maintenance Procedure Page 3

Revision: 2.0
Effective: May2007
ii Revision History
The following is a brief summary of the 4 most recent revisions to this document. Details of all
revisions prior to these are held on file by the issuing department.
Note that changes made as part of Document Maintenance (correction of broken hyperlinks) will
not be recorded in this Revision Table.
Revision No. Date Author/ Editor Changes/ Remarks
2 April 2007 − Obaid Al Farsi
(UWXZ/4)
− Christian Koepchen
(UWH/2),
− Robin Gardiner
(UPT/2)
Alignment of Well Integrity
Maintenance Procedures with the
Well Failure Model
1 01/01/2002 TWM/92
UOW 1
Initial Issue, post merger of Well
Services & Well Engineering.1
0 14/10/1998 TM Services – OTW/1 Initial Issue
iii Related Business Processes
Code Business Process (EPBM V.4.0)
EP.63 Design, Drill, Modify, Service and Abandon Well
iv Related Corporate Management Frame Work (CMF)
Documents
The related CMF Documents can be retrieved from the CMF Business Control Portal. Other,
non-CMF documents and links to information relevant to Well Engineering can be found on the
Well Engineering Documentation Page.

Revision: 2.0
TABLE OF CONTENTS
i Document Authorisation............................................................................................................3
ii Revision History........................................................................................................................4
iii Related Business Processes...................................................................................................4
iv Related Corporate Management Frame Work (CMF) Documents...........................................4
1 Introduction...............................................................................................................................7
1.1 Background.....................................................................................................................7
1.2 Purpose..........................................................................................................................8
1.3 Scope..............................................................................................................................8
1.4 Distribution/Target Audience...........................................................................................8
1.5 Review and Improvement...............................................................................................8
1.6 Step-out and Approval....................................................................................................8
2 Procedure Description..............................................................................................................9
2.1 Wellhead Integrity Test (WIT).......................................................................................10
2.2 Subsurface Integrity Test (SIT).....................................................................................52
2.3 Subsurface Integrity Test (SIT), Maintenance.............................................................111
2.4 Preventive Well Maintenance of Wellhead related Surface Equipment......................117
2.5 Corrective Well Maintenance......................................................................................120
2.6 Procedure for acid soaking to clean Tubing hanger BPV thread profile......................143
3 Identified Hazards and Threats............................................................................................144
4 Roles and Responsibilities as referred to in this document..................................................146
5 Appendices...........................................................................................................................147
5.1 Appendix 1, Forms and Reports.................................................................................147
5.2 Appendix 2, Glossary of Terms, Abbreviations and Definitions...................................147
5.3 Appendix 3, Related Business Control Documents and References..........................148
5.4 Wellhead Maintenance Guides...................................................................................150
TABLE OF FIGURES
(Double-click to view in presentation mode)
Figure 2-1, Stem Packing with Check Valve.............................................................................138
Figure 2-2, Low Pressure Grease Fitting..................................................................................139
Figure 2-3, Explosion Drawing of Valve....................................................................................140
Figure 5-4, Valve Drawing Sealant and Body Filler Connections.............................................160
LIST OF TABLES
Table 1-1, Well Types and Colour Coding....................................................................................7
Table 2-2, SCSSSV Control line pressure Limits in kPa............................................................13
Table 2-3, SCSSSV Control line pressure Limits in kPa ...........................................................21
Table 2-4, Test Pressures for Annuli Tests................................................................................53

Revision: 2.0
Effective: May2007
Table 2-5, FLS Gate Valve, Description of Parts......................................................................139
Table 4-6, Roles and Responsibilities......................................................................................146
Table 5-7, Glossary of Terms, Abbreviations and Definitions...................................................147
Table 5-8, Related Business Control Documents and References...........................................148
LIST OF EQUATIONS
N/A

Revision: 2.0
1 Introduction
1.1 Background
In April 2004 PDO introduced SP-2017, Well Failure Model as the Standard in which PDO’s
Well Integrity related requirements are defined, this in line with CP-118, Well Life Cycle Integrity
Code of Practice (WLICoP).
Since then both these documents have been under continuous development incorporating ideas
and challenges brought forward by the members of the Well Integrity Working Group resulting in
new versions of these documents.
It should be noted that all legacy Well Maintenance related documents, notably PR-1037, PR-
1472, PR-1474, PR-1477, PR-1484 shall be deemed withdrawn with the official endorsement of
this Procedure.
The Well Failure Model distinguishes the following categories of well integrity related activities
and specifies these for 7 well types in terms of frequency and scope.
− Well Integrity Testing (Preventive / Planned Maintenance)
 Wellhead Integrity Test (WIT) (See Chapter below)
Note: The WIT comprises the flow-wetted parts of the completion
 Subsurface Integrity Test (SIT) (See Chapter below)
Note: The WIT comprises all the flow-wetted parts of the completion.
WIT and SIT are intended to be interventionless. However it has
been recognized that, in order to acquire true knowledge of whether
or not a valve can be considered a barrier as per the definition given
in SP-1217, Well Control Barriers, there may be a need to set plugs
in the completion or the wellhead and pressure test against these to
establish their integrity. Such a test would be called a Pressure
Integrity Test, PIT. It is PDO’s aim to move to interventionless
integrity testing using novel technologies.
 Subsurface Integrity Test (SIT), Maintenance (Chapter 2.3)
The seven Well Types are1
:
Table 1-1, Well Types and Colour Coding
Well Types Color Coding in this document
Well Type 1
High Pressure Well - >20,000 kPa (Actual CITHP) or high GLR (>300:1
gas to liquid ratio) or high H2S (>500ppm)
Well Type 2
Free Flowing low pressure Oil Well - < 20,000 kPa
Well Type 3
Gaslift Well
Well Type 4
Steam Injection well
Well Type 5
Sub-hydrostatic pumped well, minimum one casing string with or
without packer
Well Types 6 and 7
1
The Colour Coding was introduced to prevent the user from accidentally “slipping” into the wrong well type, this as the
procedures are similar yet different in the detail.

Revision: 2.0
Effective: May2007
Well Types Color Coding in this document
1) Water Injection / Disposal Well (with tubing)
2) Water Disposal Well (no tubing)
Suspended Wells (not listed as separate Well Type in the Well Failure
Model)
This Procedure further covers:
1) Preventive Well Maintenance of Wellhead related Surface Equipment (Chapter 2.4)
2) Corrective Well Maintenance (Chapter 2.5)
3) Procedure for acid soaking to clean Tubing hanger BPV thread profile (Chapter 2.6)
1.2 Purpose
This Procedure sets out the standards which all Well Maintenance related operations have to
conform to.
It forms the framework from which detailed work practice procedures can be developed and
maintained by PDO and contractor companies who perform operations on behalf of PDO.
1.3 Scope
This Procedure is applicable to all Well Integrity related operations conducted either by PDO or
Contractor personnel on all PDO well equipment.
1.4 Distribution/Target Audience
This document will be distributed to all PDO Section Heads who have interfaces with the Well
Services Operations, all Well Services Supervisors and Contractor Supervisors.
1.5 Review and Improvement
Any user of this document who wishes to provide constructive feedback, or who encounters a
mistake or confusing entry is requested to immediately notify the Document Custodian.
This document shall be reviewed as necessary by theDocument Custodian, but no less
frequently than every four years. Triggers for full or partial review of this Procedure are listed in
PR-1444, Well Engineering Management Framework in Chapter 5.2.4, Document Review.
1.6 Step-out and Approval
Step-Outs shall be managed as described in PR-1444, Well Engineering Management
Framework in Chapter 5.2.1, Variance from a Standard (Step-Out)
The Step-Out Request Form can be downloaded from here.

Revision: 2.0
2 Procedure Description
Whenever a SIT is carried out it shall be combined with a WIT.
Where pressure exists for testing, a differential pressure shall be applied across the valve being
tested by blowing down the flow line or downstream fixed volume to the minimum pressure
practical. Where it is not possible to blow down the flow line fully, the minimum pressure
differential (ΔP) at the start of test shall be 1.2 times the Allowable Leak Rate by valve size as
stated above.
Note : The reasoning behind this rule is that the purpose of leak testing valves is to assess their
likely performance in the worst case scenario; for a Christmas Tree valve this is isolation
of the well in case of a flow line rupture. In a failure situation, a greater pressure
differential would exist across the valve than under test conditions; so a “pass” under test
conditions demonstrates integrity. A “fail” under these conditions will also have occurred
before the valve has equalised; therefore this method is deemed to be a valid test
method.
Where no well pressure exists in lieu of testing, the valve shall be cycled and maintained in
accordance with manufacturers instructions; this shall be deemed a test ‘Pass’.
Note: Whenever a SIT is carried out in conjunction with a WIT, the valves will be tested using
applied pressure above LMV, if fitted, or UMV. The decision not to set a Two-Way Check
Valve below the tree (which would give information on the integrity of the lowest Master
Valve) is based on a Risk/ Cost/ Value judgement; the value of knowing the result of the
Master Valve’s status is outweighed by the effort/ cost of achieving a valid test. In risk
term this judgement leads to a rating of C2 on the PDO Risk Matrix.
In situations where CITHP is > 0 but corresponding to < 1.2 x Allowable Leak Rate, pressure
equalisation across the valve within the test period will be deemed a test ‘Fail’ as it
demonstrates condition degradation.
The Pressure Measurement Method can be either by Pressure Build-up within an enclosed
volume or by Bleed-off from an enclosed volume.
Note: When a valve test is carried out it is vital to maintain a small positive pressure in the
cavity to be tested, this to ensure
a. that there is no zero error on the gauge
b. that the cavity to be tested is already filled with fluid

Revision: 2.0
Effective: May2007
2.1 Wellhead Integrity Test (WIT)
2.1.1 Suspended Wells
When a well of any type has been suspended, the following test shall be carried out to confirm
suspension and valve(s) integrity. Where a tree is still fitted, the standard tree test shall be
carried prior to the Suspension Plug test below.
2.1.1.1 WIT Task “Function/ Leak-off test Suspension Valve(s)”
ALL WELL TYPES
TASK CODE SUVIW/ SUVOW
TASK DECRIPTION Leak-off test Suspension Valve(s)
1) Ensure the Suspension Valve is closed.
2) Bleed off downstream pressure.
3) Install the Test Manifold and a secured flexible bleed line from the appropriate Valve to a
portable waste container in accordance with .
4) Close in the bleed point.
5) Open the Suspension Valve to check for pressure.
a. Where no pressure exists for testing, maintain the valve(s) as per the Maintenance
Guide for the appropriate valve type / manufacturer.
b. Where pressure exists for testing, close the Outer or only Suspension Valve.
6) Bleed Suspension Valve downstream pressure.
7) Record the test ‘Start’ pressure in the WIMS Checklist.
8) Measure the pressure build-up above the Suspension Valve over 10 minutes using a gauge
known to be accurate.
9) Record the test ‘Finish’ pressure in the WIMS Checklist.
10) If the test result is within the Allowable Leak Rate for the tested valve’s size then record the
result as ‘Pass’ with ‘Start’ and ‘Finish’ pressures in the WIMS WIT Checklist; record the
number ‘1’ in the ‘Number of Tests done’ field.
11) If the test results in a ‘Fail’ on the first attempt, grease and cycle the valve and re-test it until
a ‘Pass’ test result is achieved or no improvement in results is seen.
a. Flush the Valve Cavity after two failed tests using flushing liquid.
12) Record the final test (last test carried out) result in the WIMS WIT Checklist including ‘Start’
and ‘Finish’ pressure and number of tests done.
Note: Carry out Steps 6 to 12 for the second valve where two valves are fitted!
2.1.1.2 WIT Task “Leak-off Test Down-Hole Plug”
ALL WELL TYPES
TASK CODE SUPW
TASK DECRIPTION Leak-off test Down-Hole Plug
1) Open the Suspension Valve(s).
2) Bleed off the pressure above the plug in stages to a portable waste drum; monitor returns.
Note: Where returns are gas, bleed off to atmosphere if safe to do so (e.g. no H2S)
3) Where pressure cannot be bled down or where the returns are in excess of available
storage capacity, abort the test and record test as ‘Fail’.

Revision: 2.0
ALL WELL TYPES
TASK CODE SUPW
TASK DECRIPTION Leak-off test Down-Hole Plug
Note: Record the type of returned fluid in the ‘free text’ field in the WIMS WIT
Checklist to aid the investigation.
6) Measure the pressure build-up in the tubing and the Tree Cavity over 4 hours as described
in the note below. Use the Well Failure Model ‘Leak Rate Equation’ to determine if the leak
rate is acceptable.
Note: Where a well is plugged or suspended, first carry out the Tree Valve Leak-off
test using any pressure that has built up above the plug. Then bleed off the
pressure above the plug, close in the bleed and carry out and extended (4
hour) inflow test on the plug recording the results at ½ hour average over the
test period (i.e. one eighth of the observed rise over the 4 hour test period).
Simply cycle and maintain the tree valves where no pressure is initially seen
above the plug.
Note: WIMS Master Data for the well will be adapted to include allowable leak rates
for any plugs fitted. So check WIMS to confirm the calculated allowable leak
rate!

Revision: 2.0
Effective: May2007
2.1.2 Well Type 1 (High Pressure Wells or high GLR or H2S Wells)
The Testing Frequency is as per SP-2017, Well Failure Model
2.1.2.1 Safety Precautions
2.1.2.1.1 Permit to Work
Ensure that PR-1172, Permit to Work Procedure is followed.
2.1.2.1.2 H2S
Well Type 1, High Risk Wells, comprises H2S wells. This Chapter highlights the particularities
relating to H2S wells and provides links to Reference Documents.
1) Comply with all items outlined in SP-1219, Drilling Specification Hydrogen Sulphide.
2) A calibrated pressure gauge fitted to the tree cap with bleed facility (in line with H2S
controls) maybe bled off to outside fence downwind of the work area.
2.1.2.2 General Preparation
1) Fit a calibrated pressure gauge with bleed facility to the tree cap. Pressure can be bled off
to a portable waste drum.
2) Establish the Valve Manufacturer, type and size and check same against data recorded in
DIMS. For Solid Block Trees also record Part Number and check same against data
recorded in DIMS.
3) Pick the correct Wellhead Maintenance Guide from the following:
a. Cameron (see Chapter 5.4.1
b. FMC (see Chapter 5.4.2)
c. Ingram Cactus (see Chapter 5.4.3)
d. McEvoy (see Chapter 5.4.4)
2.1.2.3 Notes of Guidance
1. The allowable Leak Rates for Valves are listed by valve size in the “Allowable leak rates”
tab of SP-2017, Well Failure Model.
2. Valve leak test durations are 10 minutes; SCSSSV test leak test durations are 30 minutes.
3. Where a valve to be tested is NOT fitted, omit the respective task.
4. The test pressure can be replenished from the reservoir (by opening the Master Valves) or
using an external pump unit. Both methods have advantages and disadvantages as listed
below:
a. Pumping......................keeps UMV test barrier intact but introduces HSE risks
associated with mechanical tie in to sour HP well
b. Cycling UMV...............avoids mechanical tie-in risk but breaks UMV tested barrier.
Note: Either method can be used provided risks are considered.
5. The tests and the work to be carried out are defined, for each individual well type, in
the Well Failure Model, in the worksheet titled ‘Well Integrity Testing/ Maintenance
Matrix’ (ensure work is carried out based on the approved version of the Well Failure
Model).

Revision: 2.0
6. Tests must be carried out in the order stated below as the valve status is assumed
‘as left’ from the previous test
7. Valves must not be greased before testing. Valve maintenance will be carried out
after the initial test, not before (irrespective of whether the test results is a ‘pass’ or
‘fail’), this to allow the condition ‘as found’ to be analysed in terms of failure rates for
both ‘as found’ and ‘as left’ conditions.2
Table 2-2, SCSSSV Control line pressure Limits in kPa
Minimum Pressure to activate flapper to open
3.5”, 13.7 lbs/ft Completion String Minimum pressure to activate the flapper to open = expected CITHP +
12,500 kPa (Flapper Opening Pressure) + 3,500 kPa (Safety Factor for
Equalization)
3.5”, 10.2 lb/ft Completion String Minimum pressure to activate the flapper to open = expected CITHP +
Equalization)
Equalization)
The maximum pressure for the control line used in PDO under SAP # 1000004564 is
182,000 kPa.
2.1.2.4 Testing
2.1.2.4.1 WIT Task “Carry out External Leak Test”
WELL TYPE 1 WIT
TASK CODE ELCW /CAPW
TASK DESCRIPTION Carry out external leak check
1) Check all gaskets, flanged, bolted connections and packings for leakage and rectify as
required.
2) Measure and record all annulus pressures and the closed in tubing pressure (CITHP).
Note: Pressure within bolted or flanged connections must be bled off prior to attempting
to pull up any minor weeps
2.1.2.4.2 WIT Task “Flush Instrument Impulse Lines….”
WELL TYPE 1 WIT
TASK CODE ILFW/ PRT/ PRA/ PRB/ PRC
TASK DESCRIPTION Flush instrument Impulse Lines & Check Pressure Reading
Equipment (Local and remote)
1) Shut in production at the choke, close the HIPPS valve (if fitted), shut in FWV, UMV and
LMV to isolate the wellhead from the reservoir and the flow line pressure. Use a hand pump
and control line fluid to ensure that all ‘pressure reading’ lines, i.e. those in contact with well
fluid, are free from obstruction.
2) Where transmitters are fitted, ensure that actual local pressure gauge readings agree with
remote readings. Where differences occur, rectify or note the problem in the ‘free text’ area
of the WIT Checklist.
3) Install a secured flexiline to allow safe pressure bleed-off of sour fluids from the wellhead to
a downwind location outside the well site fence area3
.
2
If the number of tests performed and recorded in WIMS equals 1 the condition as found can be concluded to have
been within limits. The data obtained in this manner will allow analysis of valve performance with a view to establishing
the appropriate long-term reliability based maintenance frequency.
3
All Harweel well sites are equipped with permanent H2S and noise monitors which may trigger
audible alarms and HIPPS / SSV closure.

Revision: 2.0
Effective: May2007
WELL TYPE 1 WIT
4) Check pressure rating, condition and specification of needle valves and replace as required.
Note: Replace all non-standard needle valves with double block and bleed valves.
Attention!
Industry pressure release incidents have been caused by impulse lines being blocked, leading
to actual pressures in annuli not being shown on the gauges. The blockages can be due to
either ingress of well fluids or build-up of valve grease. It is therefore vital to ensure impulse
lines are clear before attempting any tests or maintenance activities.
2.1.2.4.3 WIT Task “Function/ leak-off test Flow Wing Valve (Inner or only)”
WELL TYPE 1 WIT
TASK CODE FWVIW/ FWVOW
TASK DESCRIPTION Function / leak-off test Flow Wing Valve (Inner or only)
Note: This method assumes that a combination of LMV and UMV provides a leak-tight
seal.
1) Shut in production at the choke and close HIPPS valve (to be done remotely by Production
Operations).
2) ‘Zero check’ the ‘methanol line’ or ‘flow line’ pressure gauge, ensuring the line to the gauge
is open.
3) ‘Zero check’ the Swab Valve Pressure Gauge, ensuring that the Swab Valve and the line to
Gauge are open.
4) Close LMV and UMV.
5) Open FWV.
6) Bleed off pressure between HIPPS, where fitted, or Location and wellhead through KWV.
7) Close KWV and FWV.
8) Replenish Tree Cavity pressure by either pumping or cycling LMV and UMV.
9) Record “Test Start” pressure at the swab pressure gauge in the WIMS Checklist.
10) Measure the pressure drop in the enclosed tree cavity over 10 minutes using a gauge
a. Monitor the pressure rise in the enclosed flow line section between the HIPPS and
the FWV, using the ‘methanol line’ or ‘flow line’ Pressure Gauge.
Note: If the pressure rise observed on the monitoring gauge exceeds the pressure
rise corresponding to the ‘Allowable Leak Rate’, specified in the Well Failure
Model (‘Allowable leak rate’ sheet), the FWV is recorded as a ‘Fail’; such a
result also suggests that the combination of UMV/ LMV is also a ’Fail’. In this
instance, grease all valves and re-test FWV. If the result is the same then the
Well Services Supervisor or the Asset Well Integrity Engineer must be
informed before taking any further action.
11) Record Test ‘Finish pressure’ in the WIMS Checklist.
12) If the test result is within the allowable leak rate for the tested valve’s size, record the test as
a ‘Pass’ with ‘Start’ and ‘Finish pressures’ in the WIMS WIT Checklist; record the number ‘1’

Revision: 2.0
WELL TYPE 1 WIT
in the ‘Number of Tests done’ field.
a. Flush the valve Cavity after two failed tests using flushing liquid.
and ‘Finish pressure’ and number of tests done.
2.1.2.4.4 WIT Task “Function/ leak off test Swab Valve”
WELL TYPE 1 WIT
TASK CODE SVW
TASK DESCRIPTION Function/ Leak-off test Swab Valve
1) Close SV.
2) Open UMV and LMV.
3) Bleed SV downstream cavity.
5) Record the test ‘‘Start’ pressure in the WIMS Checklist.
6) Measure the pressure build-up above the SV over 10 minutes using using a gauge known to
be accurate.
result as ‘Pass’ with ‘‘Start’ and ‘Finish’ pressures in the WIMS WIT Checklist; record the
10) Record the final test (last test carried out) result in the WIMS WIT Checklist including ‘‘Start’
2.1.2.4.5 WIT Task “Function/ Leak-off test Kill Wing Valve Inner (or only)”
WELL TYPE 1 WIT
TASK CODE KWVIW
TASK DESCRIPTION Function / Leak-off test Kill Wing Valve Inner (or only)
1) Close KWVI if not already closed.
2) Bleed down KWVI downstream cavity and install a pressure gauge and double block and
bleed system.
3) Re-pressurize the tree body if required by the chosen method and allow the pressure in the
tree body to stabilize.
5) Record test ‘‘Start’ pressure in the WIMS Checklist.

Revision: 2.0
Effective: May2007
WELL TYPE 1 WIT
TASK CODE KWVIW
6) Measure the pressure build-up downstream of the KWVI over 10 minutes using the installed
pressure gauge.
Note: Repeat this Procedure for the KWVO, if fitted.
2.1.2.4.6 WIT Task “Function/ Leak-off test the Upper Master Valve UMV”
WELL TYPE 1 WIT
TASK CODE UMVW
TASK DECRIPTION Function/ Leak-off test Upper Master Valve
1) Close UMV
2) Open SV or KWV (dependent on where the measurement will be taken)
3) Open the bleed facility to bleed down the Tree Cavity to as near zero as possible – maintain
some positive pressure on the gauge.
6) Measure the pressure build-up in the Tree Cavity over 10 minutes.
2.1.2.4.7 WIT Task “Function/ Leak-off test the Lower Master Valve LMV”
WELL TYPE 1 WIT
TASK CODE LMVW
TASK DECRIPTION Function/ Leak-off test Lower Master Valve
1) Close LMV.

Revision: 2.0
WELL TYPE 1 WIT
TASK CODE LMVW
TASK DECRIPTION Function/ Leak-off test Lower Master Valve
2) Open UMV.
3) Open the bleed facility to bleed down the Tree Cavity to as near zero as possible; maintain
6) Measure the pressure build-up over 10 minutes.
2.1.2.4.8 WIT Task “Function/ Leak-off test the Down-Hole Safety Valve”
WELL TYPE 1 WIT
TASK CODE SSSVW/ APRW/ CLA
TASK DECRIPTION Function/ Leak-off test Down-Hole Safety Valve e.g. SCSSSV/ ICV/
Storm Choke or Plug
1) Open the LMV, record the CITHP.
2) Close the SCSSSV by trip function locally.
3) Open the FWV.
4) Using the choke, bleed off the pressure above the closed SCSSSV in stages to flow line
pressure.
5) Close FWV.
6) Bleed off the remaining pressure through the flexiline, hooked up to the KWV.
8) Record the A annulus pressures at the start of the test.
10) Measure the pressure build-up in the tubing and the Tree Cavity over 30 minutes using a
gauge known to be accurate; use the Well Failure Model ‘Leak Rate Equation’ to determine
if the leak rate is acceptable.
12) Record the A Annulus pressure at the end of the test.
13) Whilst conducting the above build-up survey, confirm (e.g. by looking, listening and feeling)
that there is no communication with the reservoir through the Control Line.
14) If the first test fails, cycle the valve and re-test it until the test results in a ‘Pass’ or no
improvement in results is seen. Ensure that the pressure across the SCSSSV is equalized

Revision: 2.0
Effective: May2007
WELL TYPE 1 WIT
TASK DECRIPTION Function/ Leak-off test Down-Hole Safety Valve e.g. SCSSSV/ ICV/
Storm Choke or Plug
before cycling. A pump may be required to obtain pressure above the SCSSSV.
15) Record the final test (last test carried out) result in the WIMS WIT Checklist including the
‘‘Start’ and the ‘Finish’ pressure and the ‘Number of Tests done’.
16) Bleed off any built-up pressure through the chosen bleed point.
17) Maintain (e.g. grease or lubricate) all Tree Valves.
18) Re-open the SCSSSV.
19) Adjust the Control Line pressure to within the limits stated and record the pressure in the
WIT Checklist. Recommend control line pressures, but do not adjust at the Wellhead Panel.
Notes: 1.) WIMS Master Data for the well will be adapted to include allowable leak rates for
SSSV’s. So check WIMS to confirm the calculated allowable leak rate!
2.) Where a well is plugged or suspended, first carry out the Tree Valve Leak-off test
using any pressure that has built up above the plug. Then bleed off the pressure
above the plug, close in the bleed and carry out and extended (4 hour) inflow test on
the plug recording the results at ½ hour average over the test period (i.e. one eighth
of the observed rise over the 4 hour test period). Simply cycle and maintain the tree
valves where no pressure is initially seen above the plug.
3.) For SCSSSV’s with no equalizing feature it will be necessary to equalise the
pressure across the valve with inhibited water by means of a high pressure pump
hooked up to the kill wing valve.
2.1.2.4.9 WIT Task “Visual Inspection of condition/ deflection / clashes /
instrumentation or fitting weeps”
WELL TYPE 1 WIT
TASK CODE VIW
TASK DECRIPTION Visual Inspection of the condition/ deflection / clashes
instrumentation or fitting weeps
1) Visually inspect all tree components and report any anomalies or unacceptable degradation
through free text format area of the WIT Checklist suggesting possible remedies required.
2) Visually inspect wind socks and other related well site safety equipment; report anomalies
and replace equipment as required.
Note: As this section is open to interpretation and has no clear pass or fail criteria it
is important to describe the problem noted clearly to allow the Well Integrity
Engineer to make the decision whether to request follow-up repair or not.
2.1.2.4.10 WIT Task “Function/ Maintain remaining Annulus Valves”
WELL TYPE 1 WIT
TASK CODE MAVW/ MTVW
TASK DECRIPTION Function / Maintain all Tree Valves and remaining Annulus Valves
1) Lubricate or grease all tree and annulus valves as per Maintenance Guide for the
appropriate valve type / manufacturer.
2) Return all valves to operational position.

Revision: 2.0
WELL TYPE 1 WIT
Note: To ensure the valves’ ongoing operability, it is vital that all valves (especially
tree valves) are maintained in line with Manufacturers’ Instructions
irrespective of test result.

Revision: 2.0
Effective: May2007
2.1.3 Well Type 2 (Free Flowing Low Pressure Oil Wells, < 20,000 kPa)
The Testing Frequency is as per SP-2017, Well Failure Model
recorded in DIMS.
2. Valve leak test durations are 10 minutes; SCSSSV test leak test durations are 30 minutes.
below:
a. Pumping....................keeps UMV test barrier intact but introduces HSE risks
b. Cycling UMV..............avoids mechanical tie-in risk but breaks UMV tested barrier.
Model).
4

Revision: 2.0
Table 2-3, SCSSSV Control line pressure Limits in kPa
Minimum Pressure to activate flapper to open
3.5”, 13.7 lbs/ft Completion String Minimum pressure to activate the flapper to open = expected CITHP +
Equalization)
Equalization)
Equalization)
The maximum pressure for the control line used in PDO under SAP # 1000004564 is
182,000 kPa.
2.1.3.4 Testing
WELL TYPE 2 WIT
required.
WELL TYPE 2 WIT
TASK CODE VIW
2) Visually inspect well site safety equipment; report anomalies and replace equipment as
required.
Note: As this section is open to interpretation and has no clear pass or fail criteria it is
important to describe the problem noted clearly to allow the Well Integrity

Revision: 2.0
Effective: May2007
WELL TYPE 2 WIT
1) Shut in production at the choke, close the HIPPS valve (if fitted), shut in FWV, UMV and
LMV to isolate the wellhead from the reservoir and the flow line pressure. Use a hand pump
and control line fluid to ensure that all ‘pressure reading’ lines, i.e. those in contact with well
fluid, are free from obstruction.
3) Install a secured flexiline to allow safe pressure bleed-off of fluids from the wellhead to a
portable waste drum.
Attention!
WELL TYPE 2 WIT
Note: This method assumes that a combination of LMV and UMV provides a leak-
tight seal.
1) Shut in production at the choke (if fitted), close the ESD Valve or the FWV and close the
Location Valve.
2) ‘Zero check’ the ‘flow line’ pressure gauge (if fitted), ensuring the line to the gauge is open.
the gauge are open.
4) Close UMV and LMV, if fitted.
5) Open FWV.
6) Bleed off pressure between the Location Valve and the Wellhead through the fixed flexible
bleed line.
7) Close KWV and FWV.
8) Replenish Tree Cavity pressure by either pumping or cycling UMV and LMV, if fitted.
9) Record Test ‘Start’ pressure at the swab pressure gauge in the WIMS Checklist.
10) Measure the pressure drop in the enclosed tree cavity over 10 minutes using a gauge
a. Monitor the pressure rise in the enclosed flow line section between the FWV and the
Location Valve using the Flow line Pressure Gauge.

Revision: 2.0
WELL TYPE 2 WIT
result also suggests that the combination of UMV/ LMV is also a ’Fail’. In this
instance, grease all valves and re-test FWV. If the result is the same then the
Well Services Supervisor or the Asset Well Integrity Engineer must be
informed before taking any further action.
11) Record Test ‘Finish pressure’ in the WIMS Checklist.
WELL TYPE 2 WIT
TASK CODE SVW
1) Close SV.
2) Open UMV and LMV.
6) Measure the pressure build-up above the SV over 10 minutes using a gauge known to be
accurate.
WELL TYPE 2 WIT
TASK CODE KWVIW

Revision: 2.0
Effective: May2007
WELL TYPE 2 WIT
TASK CODE KWVIW
2) Bleed KWVI downstream cavity and install a pressure gauge and double block and bleed
system.
3) Re-pressurize the tree body if required by the chosen method and allow the pressure in the
tree body to stabilize.
5) Record test ‘Start’ pressure in the WIMS Checklist.
pressure gauge.
WELL TYPE 2 WIT
TASK CODE UMVW
1) Close UMV

Revision: 2.0
WELL TYPE 2 WIT
TASK CODE LMVW
TASK DECRIPTION Function/ Leak-off test Lower Master Valve (if fitted)
1) Close LMV.
2) Open UMV.
3) Open the bleed facility to bleed the Tree Cavity to as near zero as possible; maintain some
positive pressure on the gauge.
2.1.3.4.9 WIT Task “Function/ Leak-off test the Down-Hole Safety Valve”
WELL TYPE 2 WIT
TASK DECRIPTION Function/ Leak-off test Down-Hole Safety Valve e.g. SCSSSV
1) Open the LMV or UMV, record the CITHP.
2) Close the SCSSSV by trip function locally.
3) Open the FWV.
pressure.
5) Close FWV.
6) Bleed off the remaining pressure through the secured flexiline.
10) Measure the pressure build-up in the tubing and the Tree Cavity over 30 minutes using a
gauge known to be accurate; use the Well Failure Model ‘Leak Rate Equation’ to determine
if the leak rate is acceptable.
13) Whilst conducting the above build-up survey, confirm (e.g. by looking, listening and feeling)
that there is no communication with the reservoir through the Control Line.

Revision: 2.0
Effective: May2007
WELL TYPE 2 WIT
TASK DECRIPTION Function/ Leak-off test Down-Hole Safety Valve e.g. SCSSSV
14) If the first test fails, cycle the valve and re-test it until the test results in a ‘Pass’ or no
improvement in results is seen. Ensure that the pressure across the SCSSSV is equalized
before cycling. A pump may be required to obtain pressure above the SCSSSV.
15) Record the final test (last test carried out) result in the WIMS WIT Checklist including the
‘Start’ and the ‘Finish’ pressure and the ‘Number of Tests done’.
17) Maintain (e.g. grease or lubricate) all Tree Valves.
18) Re-open the SCSSSV.
19) Adjust the Control Line pressure to within the limits stated and record the pressure in the
WIT Checklist. Recommend control line pressures, but do not adjust at the Framo Panel.
Notes: 1.) WIMS Master Data for the well will be adapted to include allowable leak rates for
SSSV’s. So check WIMS to confirm the calculated allowable leak rate!
2.) Where a well is plugged or suspended, first carry out the Tree Valve Leak-off test
using any pressure that has built up above the plug. Then bleed off the pressure
above the plug, close in the bleed and carry out and extended (4 hour) inflow test on
the plug recording the results at ½ hour average over the test period (i.e. one eighth
of the observed rise over the 4 hour test period). Simply cycle and maintain the tree
valves where no pressure is initially seen above the plug.
3.) For SCSSSV’s with no equalizing feature it will be necessary to equalise the
pressure across the valve with inhibited sea water by means of a high pressure
pump hooked up to the kill wing valve.
WELL TYPE 2 WIT
Note: To ensure the valves’ ongoing operability, it is vital that all valves (especially tree
valves) are maintained in line with Manufacturers’ Instructions irrespective of test
result.

Revision: 2.0
2.1.4 Well Type 3 (Gas lift Wells)
The Testing Frequency as per SP-2017, Well Failure Model
recorded in DIMS.
2. Valve leak test durations are 10 minutes.
3. If CITHP drops to below the required ΔP (1.2 times the Allowable Leak Rate) during the
test, then replenish CITHP using gas lift pressure.
Note: Valve tests shall be carried out with gas lift supply isolated to prevent annulus
overpressurization or bullheading into the reservoir.
4. FWV and KWV tests can be carried out at the same time to reduce deferment but SV
should be monitored during test to see any decay.
below:
a. Pumping....................keeps UMV test barrier intact but introduces HSE risks
b. Cycling UMV.............avoids mechanical tie-in risk but breaks UMV tested barrier.
Model).

Revision: 2.0
Effective: May2007
2.1.4.4 Testing
WELL TYPE 3 WIT
required.
WELL TYPE 3 WIT
TASK CODE VIW
required.
WELL TYPE 3 WIT
1) Shut in production at the choke, close FWV, UMV and LMV to isolate the wellhead from the
reservoir and the flow line from the gas lift supply. Use a hand pump and control line fluid to
ensure that all ‘pressure reading’ lines, i.e. those in contact with well fluid, are free from
obstruction.
5

Revision: 2.0
WELL TYPE 3 WIT
Attention!
WELL TYPE 3 WIT
TASK CODE FWVIW
TASK DESCRIPTION Function / leak-off test Flow Wing Valve
1) Shut in production at the choke (if fitted) and the FWV.
2) Isolate the gas lift supply by closing the annulus valves.
3) Close the Location Valve.
the gauge are open.
Note: Monitoring CITHP during FWV test makes test pressure decay noticeable.
6) Bleed off pressure between the Location Valve and the Wellhead through a fixed flexible
bleed line into a portable waste drum.
7) Record Test ‘Start’ pressure at the flow line pressure gauge in the WIMS Checklist.
8) Measure the build-up in the flow line between the FWV and Location valve using the flow
line Pressure Gauge.
Note: If the integrity of the FWV is suspect continue the Integrity test with the
Master Valve.
9) Record Test ‘Finish’ pressure in the WIMS Checklist.

Revision: 2.0
Effective: May2007
WELL TYPE 3 WIT
TASK CODE SVW
1) Close SV.
accurate.
WELL TYPE 3 WIT
TASK CODE KWVIW
system.
pressure gauge.

Revision: 2.0
WELL TYPE 3 WIT
TASK CODE UMVW
1) Close UMV
WELL TYPE 3 WIT
TASK CODE LMVW
1) Close LMV.
2) Open UMV.

Revision: 2.0
Effective: May2007
WELL TYPE 3 WIT
result.

Revision: 2.0
2.1.5 Well Type 4 (Steam Injection Wells)
recorded in DIMS.
3. FWV and KWV tests can be carried out at the same time to reduce deferment but SV
should be monitored during test to see any decay.
5. The well to be tested must be closed in well in advance prior to the test in order to
cool down sufficiently to allow intervention by personnel. Experience shows that the
required cooling period may vary between ‘over night’ in the winter and up to three
days in the summer. This must be taken into account when planning a WIT or SIT on
a steam well.
6. The test pressure must only be replenished from the reservoir (by opening the
Master Valves). If a fluid was used and subsequently accidentally trapped in any
valve cavity, temperature increase during production could lead to fluid evaporation,
associated with an uncontrolled pressure increase. This in turn could lead to
compromising the well integrity.
Model).

Revision: 2.0
Effective: May2007
2.1.5.4 Testing
WELL TYPE 4 WIT
required.
WELL TYPE 4 WIT
TASK CODE VIW
required.
WELL TYPE 4 WIT
1) Shut in production at the choke, close FWV, UMV and LMV to isolate the wellhead from the
reservoir and the flow line from the gas lift supply. Use a hand pump and control line fluid to
ensure that all ‘pressure reading’ lines, i.e. those in contact with well fluid, are free from
obstruction.
6

Revision: 2.0
WELL TYPE 4 WIT
Attention!
WELL TYPE 4 WIT
TASK CODE FWVIW
TASK DESCRIPTION Function / leak-off test Flow Wing Valve
Note: This method assumes that the Master Valve provides a leak-tight seal.
1) Shut in production at the choke (if fitted) and the FWV.
2) Close the Location Valve.
the gauge are open.
Note: Monitoring CITHP during FWV test makes test pressure decay noticeable.
5) Bleed off pressure between the Location Valve and the Wellhead through a fixed flexible
bleed line into a portable waste drum.
6) Record Test ‘Start’ pressure at the flow line pressure gauge in the WIMS Checklist.
7) Measure the build-up in the flow line between the FWV and Location valve using the flow
line Pressure Gauge.
result also suggests that the Location Valve is also a ’Fail’. In this instance,
grease all valves and re-test FWV. If the result is the same then the Well
Services Supervisor or the Asset Well Integrity Engineer must be informed
before taking any further action.
8) Record Test ‘Finish’ pressure in the WIMS Checklist.

Revision: 2.0
Effective: May2007
WELL TYPE 4 WIT
TASK CODE SVW
1) Close SV.
accurate.
WELL TYPE 4 WIT
TASK CODE KWVIW
system.
pressure gauge.
b. Flush the Valve Cavity after two failed tests using flushing liquid.

Revision: 2.0
WELL TYPE 4 WIT
TASK CODE UMVW
1) Close UMV
WELL TYPE 4 WIT
TASK CODE LMVW
1) Close LMV.
2) Open UMV.

Revision: 2.0
Effective: May2007
2.1.5.4.9 WIT Task “Function/ Leak-off test Downhole Plugs (if fitted)”
WELL TYPE 4 WIT
TASK DECRIPTION Leak-off test Down-Hole Plug (if fitted)
1) Open the LMV or UMV, record the CITHP.
2) Open the FWV.
pressure.
4) Close FWV.
5) Bleed off the remaining pressure through the secured flexiline.
9) Measure the pressure build-up in the tubing and the Tree Cavity over 4 hours as described
in the note below. Use the Well Failure Model ‘Leak Rate Equation’ to determine if the leak
rate is acceptable.
Note: Where a well is plugged or suspended, first carry out the Tree Valve Leak-off
test using any pressure that has built up above the plug. Then bleed off the
pressure above the plug, close in the bleed and carry out and extended (4
hour) inflow test on the plug recording the results at ½ hour average over the
test period (i.e. one eighth of the observed rise over the 4 hour test period).
Simply cycle and maintain the tree valves where no pressure is initially seen
above the plug.
Note: WIMS Master Data for the well will be adapted to include allowable leak rates
for any plugs fitted. So check WIMS to confirm the calculated allowable leak
rate!
WELL TYPE 4 WIT
result.

Revision: 2.0
2.1.6 Well Type 5 (Sub-hydrostatic, pumped wells)
Pumped water supply wells are included in this well type.
2.1.6.1 Well type specific risks
− Flow is controlled electrically rather than hydraulically
− Peforming a test with the pump running on the SV and KWV.
recorded in DIMS.
4) Ensure that the pump has been electrically isolated prior to start of the WIT in accordance
with PR-1172, Permit to Work Procedure and SP-1104, Electrical Safety Rules.
1. On pumped wells, pressure is unlikely to exist for testing purposes; the primary
purpose of a WIT on this well type is therefore to assess the condition and maintain
the valves.
Model).

Revision: 2.0
Effective: May2007
2.1.6.5 Testing
2.1.6.5.1 WIT Task “Adjust Stuffing Box Seals”
WELL TYPE 5 WIT
TASK CODE SPSA
TASK DECRIPTION Adjust Stuffing Box Seals
This task is specific to rod-pumps
1) Monitor the external leakage from the stuffing box with the pump running.
2) If the Leak rate exceeds those specified in the Well Failure Model, stop the pump and adjust
the stuffing box, this to give optimum sealing capability without binding.
3) Restart the pump and re-check leakage.
4) Continue steps 2 to 3 until the observed leak rate is within limits or no further improvement is
achieved.
5) Record the result as ‘Pass’ or ‘Fail’ in the WIMS Checklist.
6) Inspect the vitraulic joint and report any condition degradation in the ‘Free Text’ box in the
WIMS Checklist.
7) Inspect the polished rod and report any condition degradation in the ‘Free Text’ box in the
WIMS Checklist.
WELL TYPE 5 WIT
required.
WELL TYPE 5 WIT
TASK CODE VIW
required.
7

Revision: 2.0
WELL TYPE 5 WIT
TASK CODE VIW
WELL TYPE 5 WIT
1) This test shall be carried out with the pump running.
2) Use a hand pump and control line fluid to ensure that all ‘pressure reading’ lines, i.e. those
in contact with well fluid, are free from obstruction.
Attention!
WELL TYPE 5 WIT
TASK CODE SVW
Note: This test applies to pumped wells without rods
1) This test shall be carried out with the pump running!
2) Close SV.
4) Close in the bleed point and install Test Manifold.
accurate.

Revision: 2.0
Effective: May2007
WELL TYPE 5 WIT
1) This test shall be carried out with the pump running.
2) Use a hand pump and control line fluid to ensure that all ‘pressure reading’ lines, i.e. those
in contact with well fluid, are free from obstruction.
Attention!
WELL TYPE 5 WIT
TASK CODE SVW
Note: This test applies to pumped wells without rods
1) This test shall be carried out with the pump running!
2) Close SV.
4) Close in the bleed point and install Test Manifold.
accurate.
The pump must be isolated for greasing and/ or flushing!

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