National Academies Subsea Bolt Performance Workshop Trent Fleece BOP Operations Team Lead 11 April 2017

Foreword The following slides were developed using material that is publicly available www.bsee.gov/what-we-do/offshore-regulatory-programs/emerging-technologies/bolt-and- connector-failures The term bolt (bolting) is used generically to refer to all fasteners and connectors throughout this presentation Note of distinction – there is a subsea blowout preventer stack (BOP) component called a connector. There are two connectors on a subsea BOP: The top connector connects the lower marine riser package (LMRP) to the subsea BOP The lower connector connects the BOP to the wellhead

Overview Context – BOP equipment overview Review of historical bolting failure in Gulf of Mexico NAS questions from March 22nd meeting in Houston Failure mechanisms Location of failure Intergranular fractures Environmental loads General industry failure reporting Industry response to bolting failures Q&A

Acronyms API – American Petroleum Institute BOP – Blowout Preventer BSR – Blind Shear Ram DC – Drilling Contractor EAC – Environmentally Assisted Cracking GoM – Gulf of Mexico HE – Hydrogen Embrittlement HRC – Rockwell Hardness C LMRP – Lower Marine Riser Package NOLA – New Orleans OEM – Original Equipment Manufacturer Op – Operator/Lessee RCA – Root Cause Analysis RCFA – Root Cause Failure Analysis

Subsea BOP equipment Three BOP original equipment manufacturers (OEMs) Left – LMRP – two Annulars and control pods Right – lower BOP – seven cavity BOP

Subsea BOP equipment Left – ram BOP ‘double’ Right – ram BOP ‘triple’ Ambient Conditions at 6,000 ft WD ~2700 psi external pressure, ~ 37° f temperature

BOP equipment – blind shear ram The purpose of the blind shear ram is to close and seal the wellbore Has the ability to shear drill pipe/casing if across the BOP at time of closure Loss of BOP integrity above the blind shear ram can be mitigated Loss of BOP integrity below a blind shear ram has limited mitigation options BOP stacks are tested to rated working pressure before deployment – typically 15,000 psi per Standard 53

Bolting failures in GoM and BSEE Safety Alert May 2003: Riser bolt/insert failure Jan 2010: API flange bolt failure – Inconel 718 Nov 2012: BSR bolt failure Dec 2012: LMRP connector body bolt failure Jul 2014: API flange bolt failure Dec 2015: BSR bolt failure Feb 2016: BSEE Safety Alert 318 issued to GoM operators April, June 2016: API Bolting Workgroup meets with BSEE in NOLA and Houston August 2016: BSEE support of API Bolting Workgroup action plan

Industry bolting failures Operator DC OEM Component Hardness Coating Mechanism a Op 1 DC 1 OEM 1 Riser Insert > 35 HRC TSA/Zinc EAC b Op 2 DC 2 OEM 2 API Flange bolt 718 Inconel NA Delta phase d Op 3 Connector body bolt Zinc e DC 3 OEM 3 API Flange Bolt Op 4 DC 4 Cylinder Bolt f Op 5 BSR Bolt MP35N Ductile Overload Although the term failure is used in the presentation material, it should be noted that on all the incidents there was no loss of primary containment – wellbore fluids were secured by the BOP. The term failure is related to the mechanical integrity of the bolts.

Perspective on industry bolting failures Failures have occurred over a 15+ year time frame Five different operators, four different drilling contractors, all three OEMs Six distinct failure types – same component, same material has not failed in the same way Some operators/drilling contractors who have been deepwater drilling for > 15 years are not known to have experienced a bolting failure Historically, limited sharing of failure data (RCA) amongst other operators and drilling contractors – no formal mechanism to share data Historical BOP standards: Basic requirements for the bolts holding that equipment together

NAS questions from meeting in Houston What is the failure mechanism? Hydrogen embrittlement (environmentally assisted cracking), ductile overload, fatigue Where are the failures occurring (i.e., first thread)? Intergranular fractures? Environmental loads on equipment? Failure reporting?

a) Riser bolt/insert failure

d) Connector body bolt e) API flange Above – LMRP connector body bolt failure Left – 3” bolt - API flange failure

e) API flange failure

e) Banding, micro-hardness and thread root

e) EAC/HE Intergranular fracture Areas of ductile overload on one of the bolts (right) ‘Mixed Mode’ failure (right) Primarily intergranular (below)

Environmental loads The bending loads observed during this example deployment campaign are within the component capacity of the API 18-3/4” flange for leak criteria up to 10ksi bore pressure as well as the connector and hence do not pose a structural integrity issue with respect to strength

Coordinated industry response to bolting failures API multi-segment task group on bolting failures 28 industry SMEs Report issued March 2016 with 20 recommendations The focus was to take a holistic approach and look at all types of bolting failures that could occur in the upstream oil and gas industry, determine contributing factors, identify current mitigations, and recommend changes to industry standards. API Bolting Workgroup 15 operators, 10 drilling contractors and all three OEMs ~75 individual members Focus on short term and longer term actions to be implemented on existing equipment

API Bolting Workgroup The summary of actions taken by the workgroup: Defined “critical bolting” as bolting that the failure of which could result in loss of containment of wellbore fluids to the environment Voluntary industry adoption of API 20 E/F for critical BOP bolting Voluntary industry upgrade of critical bolting with hardness > 35 HRC Enhanced QAQC of third party manufactured bolting (i.e., sampling, API 20 E/F requirements) Updated make-up procedures, with additional engineering rigor and oversight Elimination of electroplated zinc coatings Enhanced failure reporting with wider distribution Consistent with the direction of API standards work The workgroup submits a quarterly report to BSEE on the progress of each of the above items. Report has input from OEMs, Drilling Contractors and Operators.

Failure reporting BOP Reliability Joint Industry Project reports BOP performance Reporting for all BOP components (including bolts) Beta tested in 2014, 1Q 2015 launch 29 participating companies (and growing) > 2500 BOP component defects recorded in database so far Working with BSEE for the database to meet regulated failure reporting requirements in the Gulf of Mexico Objective of the database is to drive defect elimination and compliance with API Standard 53 reporting requirements Gather high quality, industry-wide, statistically significant data to improve the industry’s approach to BOP maintenance and integrity management and to feed BOP performance data back to the manufacturers Removed reference to IADC and IOGP so that the slide was not so wordy. Please add talking point that the BOP Reliability Joint Industry Project is supported by the International Association of Drilling Contractors (IADC) and the International Association of Oil and Gas Producers (IOGP)

RCA Ken will discuss industry RCA activities The RCA process is believed to be robust, key findings from the four HE/EAC failures are very similar: Reduce the hardness (< 35 HRC) Ensure the stress values are as expected There is a continuous improvement opportunity for the industry to share learnings more effectively on safety critical equipment An example of industry collaborating in new ways is the latest blind shear ram bolt RCA Three operators, three drilling contractors and an equipment manufacturer working together to identify the root cause and implement an improvement as soon as practical

Comprehensive bolt action plan Industry action plan addresses the life of a bolt: Design (OEM specifications, API specifications) Material selection (Exotic materials may fail in exotic ways) Manufacturing (API 20 E/F) QAQC (API standards, API 20 E/F) Coating (API 20 E 2nd edition) Torque (OEM bulletins) In service monitoring (API Standard 53) Five year major inspection (API Standard 53) Replacement bolts (end of life) Reporting – definition of failure (BOP failure reporting)

Summary of coordinated industry actions The intent of the API Workgroup is to address bolting failures by: Promoting research related to improving Subsea BOP bolting performance Improving standards related to bolts and subsea BOP equipment Short and long term goals to continually improve the currently installed equipment on BOPs Promoting failure reporting, RCA and shared learnings across the industry Work with BSEE and NAS to communicate actions to address issues Focus on elimination of defects on safety critical equipment that can safeguard personnel and protect the environment

Summary of industry actions Update make-up engineering guidance Perform torque at rig per procedure with additional oversight Riser change – increased the length of the bolt, increased the width of the bolt Hardness ≤ 34 HRC QAQC verifying material specifications API 20E manufacturing and testing requirements Riser change – lowered bolt hardness to 32-34 HRC (from 34-38 HRC) Material Resistance Stress Environmental Cracking Environment Riser - what didn’t change – the cathodic protection scheme The environmental loads Investigate and minimize probable sources of environmental cracking i.e. Hydrogen sources Eliminate electrodeposited (Zinc) coating on bolting

Backup

API 20 E/F API 20 E/F is an API specification with requirements for the qualification, production and documentation of carbon, alloy steel and corrosion resistant alloy (CRA) bolting used in the petroleum and natural gas industries Key topics covered in API 20 E/F Raw material requirements Manufacturing controls (including forging, thread forming) Heat treatment Microstructure Hardness (≤ 34 HRC) Testing (NDE, dimensional, visual, sampling of heat lots) Traceability Licensed manufacturers Per API 20E, the definition of bolting – Section 3.1.1: All-thread studs, tap-end studs, double-ended studs, headed bolts, cap screws, screws, and nuts

Torque action plan All three OEMs to issue Engineering Bulletin (EB) clarifying make-up procedure for BOP critical bolting. EB at a minimum will address the following: Confirm latest revision of procedure to be utilized Number of passes to final torque Type of thread compound to be utilized Make-up pattern clearly identified Number of threads above the nut (where applicable, i.e.18.75” API Flange) Calibration of torque wrench per OEM specification Rig contractors to review OEM Engineering Bulletin and demonstrate compliance to operators, with focus on torque processes, torque values, and associated records and create a plan to address any gaps as soon as reasonably practicable The intent is to have someone in a supervisory position removed from the job verify the crew performing the work is doing the work correctly (procedure, equipment, etc.) Supervisory personnel examples – toolpusher, maintenance supervisor, offshore installation manager, subsea supervisor etc.

Cut/Paste – Riser RCA actions

Deepwater subsea field overview

EAC EAC, which includes hydrogen embrittlement, requires three conditions to exist to lead to failure EAC may cause the material to fail at loads significantly below the rated strength of the material

> 35 HRC cracking resistance Threshold stress intensity factor (Ki scc)