INT-PRO-3002 Hot Tapping Rev Date 0 13/08/2009 Remarks First Issue Approval Prepared by: Name: Date: MOH TRIYANTO FO/INT/OPS Checked by: Approved by: Name: BAMBANG DARMAWAN Name: FO/INT/OPS Date: Date: THEO SAMOSIR FO/INT “This document is the property of TOTAL E&P INDONESIE. It must not be stored, reproduced or disclosed to others without written authorization from the Company” FO / INT INTEGRITY DEPARTMENT HOT TAPPING Doc.No INT-PRO-3002 Revision 0 Date 13/08/2009 Page 2 of 11 TABLE OF CONTENTS 1. Purpose................................................................................................................... 3 2. Scope ...................................................................................................................... 3 3. Hot Tapping Definition........................................................................................... 3 4. Responsibilities...................................................................................................... 3 5. Reference................................................................................................................ 3 6. Procedure ............................................................................................................... 3 6.1. Piping or Pressure vessel.................................................................................................................4 6.2. Pipeline .............................................................................................................................................4 6.3. Preliminary Preparation ....................................................................................................................5 6.3.1 6.3.2 6.4. Limitations for Hot Tapping ..........................................................................................................5 Documents to be Prepared ..........................................................................................................5 Preparation .......................................................................................................................................6 6.4.1 6.4.2. 6.4.3. 6.4.5. 6.5. Qualification of Welding Procedure..............................................................................................6 Qualification of Welder .................................................................................................................8 Hot Tap Machine and Operator Qualification...............................................................................8 Valve Testing................................................................................................................................8 Execution ..........................................................................................................................................8 6.5.1 6.5.2 6.5.3 6.5.4 6.6. Welding onto the Equipment to be Hot Tapped ...........................................................................8 Inspection of Weld........................................................................................................................9 Hydrostatic Testing ......................................................................................................................9 Drilling or Cutting........................................................................................................................10 Documentation ...............................................................................................................................10 Appendix 1. Requested Documentation ....................................................................... 11 “This document is the property of TOTAL E&P INDONESIE. It must not be stored, reproduced or disclosed to others without written authorization from the Company” FO / INT INTEGRITY DEPARTMENT HOT TAPPING Doc.No INT-PRO-4002 Revision 0 Date 13/08/2009 Page 3 of 11 1. PURPOSE This procedure defines the references and technical requirements for hot tapping work and to be used in conjunction with SOP 03 507 HOT TAPPING which specify the safety aspect. 2. SCOPE This procedure shall be referred for any hot taping work in TOTAL E&P INDONESIE premises. 3. HOT TAPPING DEFINITION Is a method of employing an under pressure drilling machine to cut a hole in an operating piping, pipeline or pressure vessel which allows for new branch connection from the existing line or equipment without any interruption to the flow. 4. RESPONSIBILITIES SOP 03 507 contains the responsible entities in Hot Tapping Work including tasks that they are responsible to deal with. 5. REFERENCE − − − − − − − − − − − GS-EP-PVV-172 Hot Tapping. GS EP PLR 405 Design and Installation of Hot Tapping on Subsea Gas Pipelines. GS-EP-PVV-611 Welding of pressure containing piping and equipment. API RP 2201 Safe Hot Tapping Practices in the Petroleum & Petrochemical Industries. API STD 1104 (Appendix B): Welding of Pipeline and Related Facilities (In-service welding). API 510 Pressure Vessel Inspection Code, In-service Inspection, Rating, Repair and Alteration API 570 Piping Inspection Code, In-service inspection, Rating, Repair. ASME B 31.8 Gas Transmission and Distribution Piping System. ASME B 31.4 Pipeline Transportation System for Liquid Hydrocarbons and other Liquid ASME B 31.3 Process Piping. EEMUA Publication No. 185: Guide for Hot Tapping on Piping and Other Equipment. 6. PROCEDURE References listed in paragraph 5 above, all in together completely cover all requirements to be fulfilled in hot tapping work on pressure containing piping, pipeline and pressure vessel. Each reference has its own specific purpose as described, hence to be used selectively. This paragraph 6 groups references into type of equipment to be hot tapped in accordance to its scope. In this procedure does not explain contents of those references; hence it is mandatory for hot tap work performer to read, to understand and finally to implement it. “This document is the property of TOTAL E&P INDONESIE. It must not be stored, reproduced or disclosed to others without written authorization from the Company” FO / INT INTEGRITY DEPARTMENT HOT TAPPING Doc.No INT-PRO-3002 Revision 0 Date 13/08/2009 Page 4 of 11 6.1. PIPING OR PRESSURE VESSEL To carry out hot tapping work onto piping or pressure vessel, the following documents shall be referred − GS-EP-PVV-172 This specification defines the requirements for a hot tap connection onto a pipe or pressure vessel. − GS-EP-PVV-611 : This specification specifies minimum requirements for welding, heat treatment and non-destructive examination of pressure containing piping and pressure vessel, which is referred by GS-EP-PVV-172. − API STD 1104 (Appendix B): This standard provides recommended welding practices for making repairs to or installing appurtenance on pipelines and piping system that are in-service. − API RP 2201: This recommended practice provides information to assist in safely conducting hot tapping operations on equipment in service. − API 510 : This inspection code covers the in-service inspection, repair, alteration and rerating activities for pressure vessel and the pressure relieving devices protecting these vessels. This code refers to API RP 2201 when making on-stream weld. − API 570 : This inspection code covers inspection, repair, alteration and rerating procedure for metallic piping systems that have been in-service. This code requires any welding conducted on piping component in operation must be done in accordance with API RP 2201. − ASME B 31.3 : Process Piping. This standard covers the design, fabrication and testing of piping typically found in petroleum refineries and related processing plant. - EEMUA Publication No. 185 : This Guide provide information covers welding and cutting (drilling/trepanning) operations and other technical consideration and give guidance on how to carry out hot tapping a safe operation. 6.2. PIPELINE To carry out hot tapping work onto pipeline, the following documents shall be referred: − GS EP PLR 405 : This specification covers the recommended practices and minimum requirements to perform a hot tap operation onto a subsea gas carrier pipeline. − API STD 1104 (Appendix B): This standard provides recommended welding practices for making repairs to or installing appurtenance on pipelines and piping system that are in-service “This document is the property of TOTAL E&P INDONESIE. It must not be stored, reproduced or disclosed to others without written authorization from the Company” FO / INT INTEGRITY DEPARTMENT HOT TAPPING Doc.No INT-PRO-4002 Revision 0 Date 13/08/2009 Page 5 of 11 − API RP 2201: This recommendation practice provides information to assist in safely conducting hot tapping operations on equipment in service. − ASME B 31.4 : This standard covers the design, fabrication, installation, inspection and testing of pipelines facilities used for the transportation of liquid hydrocarbon. − ASME B 31.8 : This standard covers the design, fabrication, installation, inspection and testing of pipelines facilities used for the transportation of gas. - EEMUA Publication No. 185: This Guide provides information covers welding and cutting (drilling/trepanning) operations and other technical consideration and give guidance on how to carry out hot tapping a safe operation. 6.3. PRELIMINARY PREPARATION 6.3.1 LIMITATIONS FOR HOT TAPPING Limitations for hot tapping are stipulated in: − GS-EP-PVV-172 paragraph 5, − API RP 2201 paragraph 6 and 9 and − GS-EP-PLR-405 paragraph 4. Following conditions - WHERE HOT TAPPING SHALL NOT BE DONE - generally applicable for all equipments, − Equipment is containing gas > 35% of oxygen. − Equipment is under vacuum. − Wall thickness is < 6 mm. − Metal at area of hot tapping are containing internal defect particularly lamination. − PWHT was performed at construction stage because the nature of base metal, its thickness or risk of corrosion. − Piping or Equipment is internally coated, claded or lined. − Radius of head or bend. − Distance closer than 18 in to a flange or threaded connection, or closer than 3 in to a welded seam, unless determined by an engineering review to be acceptable by using Finite Element Analysis (FEA) − Up stream of rotating machine, unless such equipment is protected by a filter. 6.3.2 DOCUMENTS TO BE PREPARED As required in GS-EP-PVV-172 paragraph 6, GS-EP-PLR-405 paragraph 8.1 and API RP 2201 paragraph 8, contractor shall submit the following document to Company prior to commencement of the work, but not limited to: A. Approved for construction (AFC) Drawing. B. Finite Element Analysis (FEA) - Branch design calculation and stress analysis. - Hot tap calculation (ensure that material stress at welding temperature is still higher than internal pressure of equipment during welding). “This document is the property of TOTAL E&P INDONESIE. It must not be stored, reproduced or disclosed to others without written authorization from the Company” FO / INT INTEGRITY DEPARTMENT HOT TAPPING - Doc.No INT-PRO-3002 Revision 0 Date 13/08/2009 Page 6 of 11 Hydrostatic test calculation Welding stress calculation. C. Procedure. - Hot tapping procedure, shall include the following aspect: Travel distance calculation Step by step when the pilot drill pass‐through the pipe wall, complete coupon cut‐off and maximum allowable boring distance. Sketch must be available on the procedure. Things to be done when the machine jammed and contingency plan In‐service welding and assessment on the need of supporting for hot tapping machine to prevent line distortion or bending caused by the machine weight - NDT Procedure and personnel qualification. - Hydrostatic test procedure (including the welded branch, valve and hot tap machine) D. Others - Material data (existing and new) (including CE, Carbon content) - Wall thickness report - Lamination or other imperfection scanning result - Hot tap equipment technical specification, test report and operator qualification. - Valve data and test report 6.4. PREPARATION 6.4.1 QUALIFICATION OF WELDING PROCEDURE Welding procedure qualification for hot tapping work shall be done on the test joint by simulating of thermal condition which is equivalent to or more severe than typical in-service welding application. API 1104 Appendix B can be used as guideline. For metal thickness greater than 1/2 in. (12.7 mm), the effect of flow on both weld cooling rates and the risk of burn-through may be negligible. The base metal thickness qualified (T) for thickness qualification greater than 12.7 mm shall be group as follows: - 12.7 ≤ T ≤ 19.1 mm. - T > 19.1 mm For metal thickness less than or equal to 12.7 mm, in addition to the requirement of the applicable standard, the following requirements either for piping, pressure vessel and pipeline shall be fulfilled: A. Wall thickness of test assembly for welding procedure and welder qualification shall be equal to or smaller than wall thickness of equipment to be hot tapped. The minimum base metal thickness qualified is the thickness of test coupon or 6 mm whichever is less and the maximum is 19.1 mm. B. Carbon content and carbon equivalent of the test assembly shall be equal to or higher than carbon content and carbon equivalent of equipment to be hot tapped. If carbon content is higher the 0.22%, then pre-heating may be applied. C. Water or Motor Oil at certain velocity to be used for simulation, unless by calculation it is proven that other fluid is more severe or same with the actual condition. Fluid Velocity shall be measured during the qualification “This document is the property of TOTAL E&P INDONESIE. It must not be stored, reproduced or disclosed to others without written authorization from the Company” FO / INT INTEGRITY DEPARTMENT HOT TAPPING Doc.No INT-PRO-4002 Revision 0 Date 13/08/2009 Page 7 of 11 D. Only low hydrogen welding process shall be used for welding in order to minimize the possibility of hydrogen cracking occurrence. E. For encirclement sleeve/tee, bevel preparation for longitudinal seam weld shall follow the sketch in figure 1. F. Only temper bead deposition sequence and a welding sequence which minimizes residual stress permitted to be used for in-service welding. It must be clearly described in the procedure. Sample of temper bead deposition sequence is shown in figure 2. G. Maximum allowable hardness on coarse-grained heat affected zone is 300 HV5. Macro hardness survey shall be conducted as per figure 3. Additional macro-section and hardness survey shall be taken on each intersection longitudinal weld and circumferential weld. Figure 1 Permitted bevel preparation for longitudinal seam (Encirclement Sleeve & Tee) End Pass End Pass B n n A Figure 2 Sample of temper bead deposition sequence 1 mm 0.5 mm 2 mm 1 mm 0.5 mm 1 mm 2 mm 0.5 mm 1 mm 0.5 mm 1 mm Figure 3 Micro Hardness Survey “This document is the property of TOTAL E&P INDONESIE. It must not be stored, reproduced or disclosed to others without written authorization from the Company” FO / INT INTEGRITY DEPARTMENT HOT TAPPING Doc.No INT-PRO-3002 Revision 0 Date 13/08/2009 Page 8 of 11 Several heat input prediction methods have been developed, including thermal analysis computer models. These or other proven methods are useful in predicting the heat input required for a given in-service welding application and predicted hardness value. They are recommended to be used, but NOT as a substitute for procedure qualification. 6.4.2. QUALIFICATION OF WELDER Welder shall have qualification in in-service welding in accordance with applicable standard or specification and hold a valid MIGAS’s welder certificate. They shall be familiar with welding equipment and welding procedure to be used. 6.4.3. HOT TAP MACHINE AND OPERATOR QUALIFICATION. To prevent burst, stuck/jammed and loose of cut coupon the maximum working pressure and temperature rating of the hot tapping machine shall never be exceeded; each tapping machine to be used shall be qualified through full size test. If the machine will be used on several locations, then largest tapping bore with thickest wall on largest diameter of matching pipe (the size subject for approval) shall be simulated in the full size test and length of valve shall be considered during the simulation. The contractor shall able to show the machine’s logbook and performed leak test for the machine before execution of hot tapping job. Previous leak test certificate is acceptable if it was done no later than 1 year provided no repair or replacement of seal tight components has been done after the test. Machine, cutter and its accessories utilization must be well-matched for the hot tap purpose in term of tap size, material and fluid service. Some comfortable margin should be considered to avoid any problem during tapping operation. The simulation shall be carried out by the hot tapping operator, who is going to operate the machine during actual operation and must have at least three years experience with the same type of machine. 6.4.5. VALVE TESTING The valve shall be pressure tested to check its tightness in the shut-off position; this test must be done in accordance with ASME B16-34 (“valve closure test”) and shall be witnessed by Company Representative. Test report shall be submitted prior to commence the work. 6.5. EXECUTION 6.5.1 WELDING ONTO THE EQUIPMENT TO BE HOT TAPPED − Welding shall only be carried out by using approved and qualified welding procedure and welder − The welding shall be done on the exact location marked before which satisfy the limitation stipulated in paragraph 6.3.1 above. − Immediately before welding is commenced the welding parameter such as Ampere, Voltage and welding speed shall be tried on a test coupon to ensure that heat input still in the range of WPS. − Welding shelter shall be provided. − During welding, a flow speed of at least 0.40 m/s for gas and 0.4 to 1.2 m/s for liquid is recommended. And a suggested maximum velocity for liquid flow during welding is 1.75 m/s to avoid rapid cooling of the weld. “This document is the property of TOTAL E&P INDONESIE. It must not be stored, reproduced or disclosed to others without written authorization from the Company” FO / INT INTEGRITY DEPARTMENT HOT TAPPING Doc.No INT-PRO-4002 Revision 0 Date 13/08/2009 Page 9 of 11 − It is also recommended to reduce the pressure by 1/3 to ½. Furthermore, for general safety reason, the pressure of fluid inside the run pipe or equipment shall not exceed 70 bar nor shall it exceed the maximum working pressure of the hot tap equipment if this is lower. − Under certain conditions, such as when welding or hot tapping on a flare line, it is necessary to purge or flood the line with steam, inert gas, or hydrocarbon gas to prevent the formation of flammable mixtures. There may be insufficient or interrupted flow which can results in a flammable mixture during the welding operation. In these circumstances it may be necessary to purge or flood the line with steam, inert gas, or hydrocarbon gas to prevent the formation of flammable mixtures. − 6.5.2 INSPECTION OF WELD − After completion of welding and prior to drilling, the weld shall be visually inspected and Nondestructive Tested. For materials with MSYS 60.000 Psi and above the NDT shall not be carried out sooner than 48 hours after completion of welding. − Inspection shall be performed and evaluated strictly as per approved procedures − Any un-acceptable defect shall be repaired using qualified and approved repair procedure and re inspected. − Repair of welding shall be performed in accordance with a qualified WPS for repair. Only one repair of weld root shall be permitted in the same area. Except for weld root, two repair attempts shall be permitted in the same area of weld. In such case, hot tap to be relocated and the fault hot tap to be reinstated. 6.5.3 HYDROSTATIC TESTING − Welded branch shall be hydrostatic tested after completion prior to drilling/trepanning. − Technical calculation by FEA shall be done prior to hydrostatic test to ensure that the run pipe can withstands the test pressure. Especially to prevent the adverse effect on the split tee fillet welds during the hydrostatic test shall be part of the engineering assessment − The test pressure shall be 1.1 time of Maximum Allowable Operating Pressure (MAOP) or design pressure whichever is less, unless otherwise contractor defines that after engineering assessment of the existing piping system or pipeline can not withstand the test pressure as proven in calculation, in this case the test pressure may be reduced but in no case less than the present operating pressure. − After installation, hot tap machine shall be leak test complete with valve. This operation may be done together with welded branch hydrostatic test or separate using diesel oil. − The test pressure shall not be greater than the machine maximum working pressure, but in no case lesser than present operating pressure of piping system or pipeline. − In case 1.1 x MAOP or design pressure whichever is less can not be achieved then the new MOP shall be reduced to test pressure divided by 1.1. “This document is the property of TOTAL E&P INDONESIE. It must not be stored, reproduced or disclosed to others without written authorization from the Company” FO / INT INTEGRITY DEPARTMENT HOT TAPPING Doc.No INT-PRO-3002 Revision 0 Date 13/08/2009 Page 10 of 11 6.5.4 DRILLING OR CUTTING Velocity of liquid shall not exceed the allowable operating parameter of machine with maximum 5 m/s and 10 m/s for liquid and gas respectively. 6.6. DOCUMENTATION Upon completion the hot tapping works, all documents required in para 6.3.2 of this procedure to be compiled in a QA/QC dossier files including the following reports and shall be submitted to Company: − Visual and NDE examination report − Welding Summary/Welding Log − Pressure Test Result − As build drawing “This document is the property of TOTAL E&P INDONESIE. It must not be stored, reproduced or disclosed to others without written authorization from the Company” FO / INT INTEGRITY DEPARTMENT HOT TAPPING Doc.No INT-PRO-4002 Revision 0 Date 13/08/2009 Page 11 of 11 APPENDIX 1. FORM NO. INT-FRM-3017 - REQUESTED DOCUMENTATION Record No Project / OA No. No 1 2 3 4 5 6 7 8 9 Status : : Requested procedures and documentation for Hot Tapping Approved for construction (AFC) Drawing Finite Element Analysis (FEA): - Branch design calculation and stress analysis. - Hot tap calculation (ensure that material stress at welding temperature is still higher than internal pressure of equipment during welding). - Hydrostatic test calculation - Welding stress calculation Inspection and Test Plan (ITP) In-service Welding Procedure Specification (WPS) and its Procedure Qualification Record (PQR). Welder List and their certificate Non-destructive Testing Procedure (NDT procedure); Signed by Valid Level III Personnel and personnel qualification. Welding Map and NDT plan Electrode Handling Procedure Hydro test procedure (including the welded branch, valve and hot tap machine) 10 Hot Tapping procedure, shall include the following aspects: - Travel distance calculation - Step by step when the pilot drill pass-through the pipe wall, complete coupon cutoff and maximum allowable boring distance. Sketch must be available on the procedure. - Things to be done when the machine jammed and contingency plan - In-service welding and assessment on the need of supporting for hot tapping machine to prevent line distortion or bending caused by the machine weight. 11 Others Material data (existing and new) (including CE, Carbon content) Wall thickness report Lamination or other imperfection scanning result Hot tap equipment technical specification, test report and operator qualification. Valve data and test report 12 QA/QC DOSSIER shall be submitted soon after completion of an item “This document is the property of TOTAL E&P INDONESIE. It must not be stored, reproduced or disclosed to others without written authorization from the Company”
