ARPO ENI S.p.A. Agip Division IDENTIFICATION CODE STAP-P-1-M-6100 PAGE 6 OF 230 REVISION 0 148 148 149 149 150 150 150 150 152
11.4. BIT SELECTION
11.4.1. Formation Hardness/Abrasiveness 11.4.2. Mud Types
11.4.3. Directional Control 11.4.4. Drilling Method 11.4.5. Coring 11.4.6. Bit Size 11.5. CRITICAL ROTARY SPEEDS 11.6. DRILLING OPTIMISATION
12. DIRECTIONAL DRILLING
12.1. TERMINOLOGY AND CONVENTIONS
12.2. CO-ORDINATE SYSTEMS
12.2.1. Universal Transverse Of Mercator (UTM) 12.2.2. Geographical Co-ordinates
12.3. RIG/TARGET LOCATIONS AND HORIZONTAL DISPLACEMENT
12.3.1. Horizontal Displacement 12.3.2. Target Direction 12.3.3. Convergence 12.4. HIGH SIDE OF THE HOLE AND TOOL FACE
12.4.1. Magnetic Surveys 12.4.2. Gyroscopic Surveys
12.4.3. Survey Calculation Methods 12.4.4. Drilling Directional Wells 12.4.5. Dog Leg Severity
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153 155 155 156 158 158 159 159 160 161 163 165 167 172
13. DRILLING PROBLEM PREVENTION MEASURES
13.1. STUCK PIPE
13.1.1. Differential Sticking
13.1.2. Sticking Due To Hole Restrictions 13.1.3. Sticking Due To Caving Hole
13.1.4. Sticking Due To Hole Irregularities And/Or Change In BHA 13.2. OIL PILLS
13.2.1. Light Oil Pills 13.2.2. Heavy Oil Pills 13.2.3. Acid Pills
13.3. FREE POINT LOCATION
13.3.1. Measuring The Pipe Stretch
13.3.2. Location By Free Point Indicating Tool 13.3.3. Back-Off Procedure 13.4. FISHING
13.4.1. Inventory Of Fishing Tools 13.4.2. Preparation
13.4.3. Fishing Assembly 13.5. FISHING PROCEDURES
13.5.1. Overshot
13.5.2. Releasing Spear 13.5.3. Taper Taps 13.5.4. Junk basket 13.5.5. Fishing Magnet
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173 174 175 176 178 179 179 179 180 181 181 182 182 183 183 183 184 184 184 184 185 185 185
ARPO ENI S.p.A. Agip Division 13.6. MILLING PROCEDURE 13.7. JARRING PROCEDURE
IDENTIFICATION CODE STAP-P-1-M-6100 PAGE 7 OF 230 REVISION 0 186 187
14. WELL ABANDONMENT
14.1. TEMPORARY ABANDONMENT
14.1.1. During Drilling Operations 14.1.2. During Production Operations 14.2. PERMANENT ABANDONMENT
14.2.1. Plugging
14.2.2. Plugging Programme 14.2.3. Plugging Procedure
14.3. CASING CUTTING/RETRIEVING
14.3.1. Stub Termination (Inside a Casing String) 14.3.2. Stub Termination (Below a Casing String)
189
189 189 189 190 190 190 191 192 192 192
15. WELL NAME/DESIGNATION
15.1. WELLS WITH THE ORIGINAL WELL HEAD CO-ORDINATES AND TARGET
15.1.1. Vertical Well
15.1.2. Side Track In A Vertical Well. 15.1.3. Directional Well
15.1.4. Side Track In Directional Well 15.1.5. Horizontal Well
15.1.6. Side Track In A Horizontal Well
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193 193 193 194 194 194 194
15.2. WELLS WITH THE ORIGINAL WELL HEAD CO-ORDINATES AND DIFFERENT TARGETS 195 15.3. WELLS WITH DIFFERENT WELL HEAD CO-ORDINATES AND SAME ORIGINAL TARGETS197 15.4. FURTHER CODING
198
16. GEOLOGICAL DRILLING WELL PROGRAMME
16.1. PROGRAMME FORMAT 16.2. IDENTIFICATION
16.3. GRAPHIC REPRESENTATIONS
16.4. CONTENTS OF THE GEOLOGICAL AND DRILLING WELL PROGRAMME
16.4.1. General Information (Section 1) 16.4.2. Geological Programme (Section 2)
16.4.3. Operation Geology Programme (Section 3) 16.4.4. Drilling Programme (Section 4)
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200 200 200 201 201 207 208 209
17. FINAL WELL REPORT
17.1. GENERAL
17.2. FINAL WELL REPORT PREPARATION
17.3. FINAL WELL OPERATION REPORT STRUCTURE
17.3.1. General Report Structure
17.3.2. Cluster/Platform Final Well Report Structure 17.4. AUTHORISATION 17.5. ATTACHMENTS
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210 210 211 211 212 213 213
ARPO ENI S.p.A. Agip Division IDENTIFICATION CODE STAP-P-1-M-6100 PAGE 8 OF 230 REVISION 0 APPENDIX A - REPORT FORMS
A.1. INITIAL ACTIVITY REPORT (ARPO 01) A.2. DAILY REPORT (ARPO 02)
A.3. CASING RUNNING REPORT (ARPO 03) A.4. CASING RUNNING REPORT (ARPO 03B) A.5. CEMENTING JOB REPORT (ARPO 04A) A.6. CEMENTING JOB REPORT (ARPO 04B) A.7. BIT RECORD (ARPO 05)
A.8. WASTE DISPOSAL MANAGEMENT REPORT (ARPO 06) A.9. WELL PROBLEM REPORT (ARPO 13)
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215 216 217 218 219 220 221 222 223
APPENDIX B - ABBREVIATIONS
APPENDIX C - WELL DEFINITIONS
APPENDIX D - BIBLIOGRAPHY 224 228 230
ARPO ENI S.p.A. Agip Division IDENTIFICATION CODE STAP-P-1-M-6100 PAGE 9 OF 230 REVISION 0 1.
1.1.
INTRODUCTION
PURPOSE AND OBJECTIVES
The purpose of the Drilling design Manual is to guide experienced technicians and
engineers involved in Eni-Agip?s in the production of well design/studies and in the planning of well operations world-wide, using the Manuals & Procedures and the Technical Specifications which are part of the Corporate Standards. This encompasses the
forecasting of pressure and temperature gradients through casing design to the compilation of the Geological Drilling Programme and Final Well Report.
Such Corporate Standards define the requirements, methodologies and rules that enable to operate uniformly and in compliance with the Corporate Company Principles. This, however, still enables each individual Affiliated Company the capability to operate according to local laws or particular environmental situations.
The final aim is to improve performance and efficiency in terms of safety, quality and costs, while providing all personnel involved in Drilling & Completion activities with common guidelines in all areas worldwide where Eni-Agip operates.
The objectives are to provide the drilling engineers with a tool to guide them through the decision making process and also arm them with sufficient information to be able to plan and prepare well drilling operations and activities in compliance with the Corporate Company principles. Planning and preparation will include the drafting of well specific programmes for approval and authorisation.
1.2.
IMPLEMENTATION
The guidelines and policies specified herein will be applicable to all of Eni-Agip Division and Affiliates drilling engineering activities.
All engineers engaged in Eni-Agip Division and Affiliates drilling design activities are
expected to make themselves familiar with the contents of this manual and be responsible for compliance to its policies and procedures.
1.3.
UPDATING, AMENDMENT, CONTROL& DEROGATION
This manual is a ?live? controlled document and, as such, it will only be amended and improved by the Corporate Company, in accordance with the development of Eni-Agip Division and Affiliates operational experience. Accordingly, it will be the responsibility of everyone concerned in the use and application of this manual to review the policies and related procedures on an ongoing basis.
Locally dictated derogations from the manual shall be approved solely in writing by the Manager of the local Drilling and Completion Department (D&C Dept.) after the
District/Affiliate Manager and the Corporate Drilling & Completion Standards Department in Eni-Agip Division Head Office have been advised in writing.
The Corporate Drilling & Completion Standards Department will consider such approved derogations for future amendments and improvements of the manual, when the updating of the document will be advisable.
Feedback for manual amendment is also gained from the return of completed ?Feedback and Reporting Forms? from drilling, well testing and workover operations, refer to Appendix A.
ARPO ENI S.p.A. Agip Division IDENTIFICATION CODE STAP-P-1-M-6100 PAGE 10 OF 230 REVISION 0 2.
2.1.
PRESSURE EVALUATION
FORECAST ON PRESSURE AND TEMPERATURE GRADIENTS
A well programme must contain a technical analysis including graphs of pressure gradients (overburden, pore, fracture) and temperature gradient. The following information must be included in the analysis:
a) b)
Method for calculating the Overburden Gradient, if obtained from electric logs of reference wells or from seismic analysis.
Method for defining the Pore Pressure Gradient, if obtained from data (RFT, DST, BHP gauges, production tests, electric logs, Sigma logs, D exponent) of reference wells or from seismic analysis. Formula used to derive the Fracture Gradient. Source used to obtain the Temperature Gradient.
c) d)
The formulas normally used to calculate the Overburden Gradient are:
??t???
PiP??1000 3.28?????H
??t??? 47
D?? 1.228
??t?? 200
D?????h 10 Gov??????Hi 10
=
Numbers of??second (calculated from sonic log for regularly depth
interval, i.e. every 50/100/200m) Transit time (second 10-3) Density of the formation Overburden gradient
Formation interval with the same density D Total depth (????H)
where:
PiP ??t D Gov ??H Hi
= = = = =