Hubbard 2010

 

 

IADC/SPE 128425 Nonproductive Time (NPT) Reduction Delivered Through Effective Failure Investigations Brad L. Hubbard, SPE, and Shabib J. Kadri, SPE, TH Hill Associates, Inc.; Michael J. Crotinger, Consultant; and James E. Griffith, SPE, and Eric van Oort, SPE, Shell Upstream Americas

Copyright 2010, IADC/SPE Drilling Conference and Exhibition This paper was prepared for presentation at the 2010 IADC/SPE Drilling Conference and Exhibition held in New Orleans, Louisiana, USA, 2–4 February 2010. This paper was selected for presentation by an IADC/SPE program committee following review of information contained in an abstract submitted by the author(s). Contents of the paper have not been reviewed by the International Association of Drilling Contractors or the Society of Petroleum Engineers and are subject to correction by the author(s). The material does not necessarily reflect any position of the International Association of Drilling Contractors or the Society of Petroleum Engineers, its officers, or members. Electronic reproduction, distribution, or storage of any part of this paper without the written consent of the International Association of Drilling Contractors or the Society of Petroleum Engineers is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 wor ds; illustrations may not be copied. The abstract must contain conspicuous acknowledgment of IADC/SPE copyright.

Abstract  Nonproductive time (NPT) (NPT) caused by preventable tool and equipment failures in offshore drilling and completion operations typically accounts for 5% of well delivery time, but can reach as high as 30% [1]. This equates to millions of dollars per year that could have been spent on other well delivery opportunities. Mutual benefit exists for both operators and vendors to dedicate the time and effort necessary to consistently perform comprehensive investigations and develop effective solutions to mitigate risk of repeat failures. A one-sided or inadequately supported approach to failure response can lead to incomplete analyses and insufficient solutions that treat symptoms rather than root causes, thereby sustaining or creating reliability gaps and allowing further NPT to be incurred. In recent years, Shell’s Gulf of Mexico (GOM) drilling operations formed a specialized, dedicated team to establish and facilitate an effective, sustainable approach to failure response. The team’s immediate goal was the reduction of NPT cost associated with drilling tool failures. Long term, the team’s objective was to promote a culture within both operator and vendor organizations for effective failure prevention and performance improvement. Via this team consistent representation, influence, and support is maintained during failure response activities. The team enforces vendor failure response expectations and ensures complete, unbiased analyses and solutions with appropriate local, regional and global communication within operator and vendor organizations, such that the chance of repeat failures anywhere in the industry is minimized. Since inception, the team’s efforts have facilitated a significant reduction in NPT, which translates to yearly multi-milliondollar savings. Given its evident success, the scope of this initiative has been expanded within the Americas and also in global operations. This paper reviews the approach and process, clarifies the roles, responsibilities and accountabilities for  both operator and suppliers, highlights the mutual benefits for operators and vendors, and illustrates the effectiveness of the approach through its very positive impact on operational NPT reduction.

Introduction and Background Historically, it is common practice for operators to rely on their well delivery personnel (i.e. foremen, drilling engineers and/or operations superintendents) to work with vendors to investigate and document tool and wellbore-related failures. In many cases, this type and level of support is appropriate and effective. However, investigat investigations ions into high-impact NPT events involving complex tools and operations typically require more time and effort than well delivery personnel can reasonably dedicate, given that this work has to compete with time necessary for well planning and real-time supervision activities. Without sufficient operator support and influence during failure investigations, tool vendors can (often by necessity) give less focus to failure investigations and risk mitigation efforts. This approach to failure investigations has resulted in fundamental issues (i.e. root causes) not being identified and/or addressed, which in turn leads to additional tool failures and perpetuation of high levels of NPT and associated trouble cost. Therefore, it is in the best interest of operators and vendors to assign high  priority to failure investigation and risk mitigation work, dedicating the appropriate resources, establishing a fit-for-purpos fit-for-purposee infrastructure, and allowing the work to be an integral part of the well and tool/service delivery processes. The benefits to the

 

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operator are self-evident. The tangible benefits to the supplier come from the ability to demonstrate excellence in service  provision to the operator, thereby strengthening the (contractual) relationship. Through active support and involvement in failure investigations driving down NPT, suppliers are now able to demonstrate that they are competitive from a total cost  perspective, including including not only the d direct irect cost of goods and services but also the indi indirect rect costs associ associated ated with NP NPT. T. Collaboration on preventable tool and equipment failures has its parallels in workplace safety, which remains an area of significant focus and commitment for both operators and vendors. Compared to other industries, the oil and gas industry compares well in workplace safety performance. In the U.S. through the combined efforts of operators and suppliers, there were 3.0 job-related, nonfatal injuries/illnesses per 100 full-time workers in 2007 as compared to 3.1 injuries in mining, 5.6 [2]

injuries in manufacturing and 4.2 injuries in the private sector, and this trend holds true from 1998 through 2007 . Similar operator and vendor ownership and dedication are necessary for the sustained reduction of NPT from tool failures, especially as the complexity and challenges of drilling operations increase. In 2006, Shell initiated a focused effort to reduce NPT hours and cost associated with failures of problematic drilling tools in their GOM operations. Such effort was deemed necessary since the level of NPT associated with tool failures was consistently high and showed no signs of abating. This focused approach employs a flexible, fit-for-purpose Root Cause Failure Analysis (RCFA) process and a specialized team that is dedicated to investigate specific, high-impact NPT events via the RCFA process. This team relieves well delivery personnel from the responsibility of carrying out comprehensive failure investigations, and the team supports well delivery personnel by developing (with the vendor) and communicating the RCFA  based corrective actions and recommendations for minimizing minimizing risk of similar failures. This team is known as the Root Cause Failure Analysis / Trouble Action Team (RCFA/TAT). Since its inception, the team has grown from two to six people (as of April 2009), providing RCFA coverage to drilling and completions operations throughout North America. The following sections of this paper discuss the methodology for the team’s approach and the corresponding implementation implementation highlights, results and conclusions. A case study is also presented in Appendix A.

Methodology The features of the RCFA/TAT process considered essential for success are:  

A manageable and focused work scope,

 

Dedicated personnel/team with clear roles and responsibilit responsibilities ies to conduct failure investigations,

 

Clearly defined vendor responsibilities and accountabilities during failure investigation and while implementing corrective actions, and

 

Clear and timely communication with the interested parties (drilling teams, vendors, contracting and procurement, and quality services).

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The RCFA/TAT does not follow a specific RCFA process (such as FMEA, Fault-Tree Analysis, etc.) [3]  giving the team sufficient flexibility to smoothly interface with the vendors’ internal failure analysis processes. Moreover, each team member has a sound understanding of either drilling or completions tools and related operations, and has extensive experience in conducting failure investigations. The RCFA process employed by the RCFA/TAT is summarized in Figure 1. The idea of effective scope management remains a key to the success of the RCFA/TAT. The team focuses its work scope and efforts so that the highest impact events receive the most attention. This is accomplished by selecting only those NPT events exceeding six hours of trouble time as candidates for follow-up. Failures in the drill string (including the BHA) exceeding six hours are investigated by default. For all other NPT events exceeding six hours the RCFA/TAT consults the key stakeholders (Operations Superintendent and Drilling Engineer) and determines the forward plan based on their input.  NPT events lasting less than six hours are not considered considered for RCFA except by special request by the key stakeholders. These smaller events are simply documented for impact and tracked in meaningful key performance indicators (KPIs) for trends. The six-hour threshold was selected because a detailed review of historic NPT data for GOM operations revealed that most of the NPT (approximately 80%) occurred due to a relatively small percentage (approximately 20%) of events/failures, each lasting six hours or more. Moreover, the NPT data also indicated that the majority of tool related NPT occurred due to  problems in complex complex BHA tools such as MWD, L LWD, WD, RSS aand nd underreamers. The primary function of the RCFA/T RCFA/TAT AT is to conduct RCFAs. Within the GOM drilling organization, the RCFA team bears the responsibility of initiating RCFAs (with input from drilling teams) and conducting RCFAs while working closely with the vendors to determine the root cause of each failure and to identify the necessary corrective actions to prevent reoccurrence. RCFA team members do not have the additional roles and responsibilities of drilling or completing wells, coordinating the

 

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qualification or inspection of tools, etc. While each team member may have several different roles within the RCFA process, each role is clearly defined. The RCFA Coordinator monitors the online operational reports (morning reports) and identifies  NPT events. RCFA investigations are initiated on certain events based on the nature of the issue or failure and associated  NPT. After determining determining whether an RCF RCFA A is desirable, the team assigns assigns a Lead Investigator to spearhead spearhead the investigation to completion. Input from other team members, the stakeholders and subject matter experts is obtained as necessary.

Figure 1: RCFA process overview illust illustrating rating RCFA/TAT methodology

The RCFA/TAT works closely with the vendors to conduct failure investigations as a team instead of engaging in a “blame game”. The RCFA/TAT’s unbiased and objective approach has won the vendors’ confidence and allowed the team to create a win-win situation for the operator and its vendors. The RCFA/TAT focuses on long-term solutions applicable at a fundamental level to address the problems identified during failure investigations. The RCFA/TAT RCFA/TAT works with the interested  parties to improve existing procedures (design, inspection, assembly, function testing and field operational  procedures/practices)  procedures/practice s) at the basic applicable level. The RCFA/TAT avoids corrective actions that require the vendor to implement supplemental procedures and/or operator-specific operator-specific criteria. The RCFA/TAT also tries to apply each particular solution on a larger scale, both generally and globally. The team works with the vendor to determine whether the root cause of a failure in one tool can cause a failure in other types of tools and consequently the resulting corrective actions can be proactively implemented for the other tool. Similarly, procedural  problems identified with a particular vendor’s shop may occur in another shop, consequently, the corrective actions should apply to other shops in the region and across the world, as applicable. Thus, the RCFA/TAT encourages vendors to take ownership in identifying and implementing preventative measures and opportunities for improvement related to the general and global applications of RCFA solutions. Effective communication has been a key success factor of the RCFA/TAT. The RCFA/TAT ensures that all confidential or restricted information obtained and reported (including sensitive vendor and/or well data) during failure investigation is closely managed and selectively communicated. The success of the RCFA/TAT depends on its ability to maintain good working relationships with vendors and well delivery teams, and such relationships depend heavily on mutual respect and confidence, which are both strongly influenced by responsible use of sensitive data.

 

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The RCFA/TAT has communicated a set of vendor failure response requirements to the vendors to establish clear expectations on vendor deliverables. This facilitates a smooth interface with each vendor’s failure investigation process without causing the vendor to actually modify its internal failure investigation process. Per these requirements, the vendor is required to send a detailed notification within 24 hours of a tool failure incident that led to NPT. The RCFA/TAT coordinates with the vendor, the key stakeholders and any third party engineers/experts to understand the circumstances surrounding the failure, determine a tentative investigation plan and schedule a tool disassembly/analysis at the vendor’s facility. The vendor is expected to provide a post-teardown report (preferably within two working days) after the tool is disassembled and initial analysis has been completed. The vendor is furthermore encouraged to provide weekly updates on the progress of the investigation. Once the investigation has been completed and the corrective actions have been finalized, the vendor is required to furnish a final failure investigation report containing the details, findings and conclusions from the failure investigation and correctives actions/recommendations to prevent the reoccurrence of the failure. If necessary, a failure response meeting (after action review) is held after the investigation has been completed to address any questions or concerns from the interested parties. The RCFA/TAT regularly communicates with the interested parties to ensure that a detailed and unbiased investigation is conducted and that appropriate corrective actions are implemented. The RCFA/TAT provides a concise preliminary report to the key stakeholders after the tool disassembly and preliminary analysis has been completed. This preliminary report contains the findings/conclusions from the analysis, any immediate corrective actions/recommendations to mitigate risk of a repeat failure and a tentative forward plan for the failure investigation. Regular updates are also provided to the key stakeholders as the investigation progresses. Once the failure investigation is complete, the RCFA/TAT compiles and reviews a concise RCFA Report (Figure B-1) that summarizes the details and outcome of the RCFA investigation. The concerned party (usually the vendor) is requested to review and approve the relevant corrective actions and recommendations. The RCFA report is then submitted to the key stakeholders of the investigation (Drilling Engineer and Operations Superintendent) and any applicable technical experts for a formal review and approval. The RCFA/TAT compiles corrective actions and recommendations related to NPT events due to tool application and operational issues into Risk Mitigation Reports (Figure B-2). Relevant RCFA reports, global alerts, etc. are also included as references in the Risk Mitigation Reports. The RCFA/TAT publishes quarterly RCFA Awareness Bulletins (Figure B-3) containing highlights of newly initiated and completed investigations, new risk mitigation information related to tool application/operation, and updates on key ongoing investigations. The information generated during failure investigations is disseminated throughout the organization using preliminary reports, RCFA Reports, Risk Mitigation Reports and quarterly RCFA Awareness Bulletins. All the RCFA Reports, Risk Mitigation Reports and Awareness Bulletins are available on the RCFA/TAT’s website in an easily searchable and retrievable form with the appropriate access restrictions. The RCFA/TAT RCFA/TAT encourages interested parties, such as well delivery and performance improvement teams, to visit the RCFA/TAT website, review the information and apply it as appropriate during well plannin g activities and before selecting particular tools and vendors for operations. Through efficient data gathering and information dissemination from investigated failure events, the RCFA/TAT has become an integral part of the well delivery process. In addition to working with the well delivery teams and subject matter experts, the RCFA/TAT also interfaces with other organizations such as Contracting and Procurement (C&P) and Quality Services. The RFCA/TAT supports C&P to obtain commercial resolution from vendors by providing technical information on tool failures. The RCFA/TAT participates in Service Quality Meetings and Business Performance Reviews that are arranged by C&P on a regular basis to review the highs and lows of vendor performance, KPIs and improvement areas. Ultimately, RCFA/TAT support of C&P facilitates more accurate evaluation of vendor performance, leading to effective contract adjustments and/or market share allocation decisions. The R CFA/TAT also interfaces with the Quality Services organization to maximize the effectiveness of vendor audits and to modify current inspection requirements and/or quality plans based on the information gathered during failure investigations. In summary, the RCFA/TAT manages its work scope to maximize the benefits of its efforts, closely and objectively works with the vendors to create a win-win situation for the operator and the vendor, wisely manages and selectively communicates information generated during failure investigations, finds root causes to failures and applies solutions at a fundamental level, extrapolates these fundamental solutions for general and global application, and establishes clear expectations for failure response within the operator and v endor organizations.   Implementation Highlights As discussed in previous sections, a specialized, dedicated team and fit-for-purpose methodology were established to reduce  NPT costs from specific specific tool failures in GOM drill drilling ing operations. The The implementat implementation ion highlights are summarized belo below: w:

 

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In June of 2006, an initial assessment period began and allowed the development scope and priorities to be defined, such that the team could be adequately resourced for the scope of work and would subsequently focused on the highest value issues while maintaining a realistic workload. The necessary provisions were built into the methodology to address the identified barriers.

 

A steering committee of regional managers was established to allow for expedited review and approval of development proposals and updates.

 

In September 2006, the process was officially commissioned in the Americas region, focusing on specific types of tool NPT events in GOM operations within the team’s approved work scope.

 

The team developed techniques and deliverables for effectively communicating RCFA findings, actions, and recommendations to well delivery personnel. Team key performance indicators were also established.

 

In early 2007, the team’s success was evident by the increasing pull for assistance from the well delivery teams, allowing for additional team resourcing and scope expansion (i.e. focused coverage of land operations).

 

In April 2009, the team added another resource and expanded its scope to include GOM completions operations.

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Overall, the current RCFA/TAT consists of six people providing RCFA coverage to land and offshore drilling and completions operations in North America. The fundamental approach is the same for each RCFA coverage area, employing a consistent methodology with any necessary fit-for-purpose adjustments based on the type and nature of the operations and particular tools withi within n that coverage area. The overall team’s team’s goal and objectives remain the sam samee regardless of a pplication of particular the specific RCFA focus areas and related fit-for-purpose process adjustments.   Results The immediate RCFA/TAT goal was to significantly reduce the occurrence of tool failures and the associated NPT. In September of 2006, the RCFA/TAT began conducting RCFAs on failures occurring during drilling operations in the GOM. The RCFA/TAT primary focus was on drill string and BHA component (i.e. MWD, LWD, RSS, motors, underreamers, etc.) failures as these were determined to be significant contributors to overall NPT in the GOM. Figure 2 clearly shows the success the RCFA/TAT has had in reducing tool failures over the last three years in GOM drilling operations. During and  prior to the first six months of this initiative, NPT failures of focus tools averaged five per month. During the three years of this initiative, failure frequency in the GOM has declined 60% to less than two failures per month. Actual NPT (as a percent of total drilling rig-hours) has been cut in half and failure costs (as a percent of total drilling cost) have been reduced by twothirds.

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Figure 2: Frequency of tool failu failures res in GOM drill drilling ing operations

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The success of the RCFA/TAT in the GOM has provided justification to expand the RCFA/TAT model to include both drilling and completion operations throughout North America. The process was implemented for Land drilling and completion operations during the fourth quarter of 2007 resulting in a ~20% reduction in NPT costs thus far. It was implemented for GOM completions this year. The process has also been accepted as a global best practice and as such has  been implemented in operations in the Asia-Pacific and Europe (North Sea) regions. The expansion of the RCFA/TAT throughout global operations has enabled the different teams to share alerts and corrective actions for tool failures worldwide so that repeat failures can be avoided globally.   Conclusions For highly capital-intensive projects such as deepwater wells in the GOM, NPT associated with preventable tool and equipment failures can amount to millions of dollars per well. The potential savings from reducing NPT represents an attractive target to any operator, with mutual interest for tool vendors interested in demonstrat ing excellence in service delivery. The RCFA/TAT is a team of qualified failure analysts whose sole responsibility is the analysis and reduction of  NPT. Since the team’s formation in 2006, NPT due to drill string and BHA tool and equipment failures during drilling failures. operations in the GOM has been cut in half and there have been no repeats of investigated failures.   The RCFA/TAT process has been very successful in reducing NPT. Several general features in the process have been critical to this success. These are: 1.  The RCFA/TAT does not get involved in the daily operations of well delivery. Their sole focus is NPT reduction. They have no other responsibilities responsibilities to distract them from their objective. 2.  A manageable workload is established, which allows the team to be effective. There is so much NPT that one has to  be selective to successfully conduct in depth and competent investigations. For this reason the RCFA/TA RCFA/TAT T only selects those types of failures with the potential to cause significant NPT. 3.  RCFAs are conducted with the full support and cooperation of the tool and equipment vendors. Both vendors and operators benefit fr om the reduction of NPT, which makes vendor tools more reliable (increasing market share) and operator costs lower. The pooling of the expertise of the vendors and the RCFA/TAT substantially increases the likelihood that the root cause will be identified and that effective corrective actions will be developed to prevent repeat failures. 4.  Clear expectations have been established for vendor failure response. These expectations define vendor deliverables and communication milestones, establishing a smooth and structured interface between the RCFA/TAT and the vendor’s internal failure investigation process. 5.  The lessons that come out of an RCFA are communicated within both the operator and the vendor organizations globally. Without the appropriate global communication and response, similar, preventable failures can occur in other regions, multiplying the overall NPT and cost. 6.  When appropriate lessons that result from an RCFA into a specific tool failure are applied to the rest of the tools in that tool family. If possible the lessons are also generalized in such that they are applicable to other tool families. 7.  The RCFA/TAT uses a defin ed set of timely communication protocols to keep stakeholders and other interested  parties objectively objectively informed of the facts in an investigation as it progresses aand nd at its conclusion. conclusion. This mini minimizes mizes and dispels rumors that can cloud an investigation and interfere with the necessary working relationship between the RCFA/TAT and the vendors. The RCFA/TAT methodology has been adopted as a global best practice within the company. It has been e xpanded from drilling operations in the GOM to both drilling and completions operations throughout North America. The company’s AsiaPacific and European (North Sea) regions have also adopted the RCFA/TAT methodology with appropriate fit-for-purpose adjustments in each region. Early results from these regions are favorable and support the value of the process.   Acknowledgements T he authors pr  would to thank following individuals forWright, their support theordevelopment and execution of and the ocess:like Lance Cook,the Joseph Leimkuhler Leimkuhler, , Melvyn EdwardinTaylor Tayl and Joe Lambert, Shell E&P; RCFA/TAT Sean Ellis and DeWayne Everage, TH Hill Associates, Inc.  

 

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References 1.

Reid, D., Rosenberg, S., Montgomery, M M., ., Sutherl Sutherland, and, M., York, P. 2006. Drilli Drilling-Hazard ng-Hazard Mitigation – Reducing Nonproductive Time by Application of Common Sense and High-Value-Well Construction Techniques. Paper OTC 18084 presented at the Offshore Technology Conference, Houston, Texas, U.S.A., 1–4 May 2006.

2.  

American Petroleum Institute. 2009. W Workplace orkplace Safety (1998-2007). API Creative: 2009-104. http://www.api.org/statistics/accessapi/surveys/upload/2009-104_WORKPLACE_SAF http://www.api.org/statistics/acces sapi/surveys/upload/2009-104_WORKPLACE_SAFETY.pdf. ETY.pdf.

3.

Mobley, R R.. K. 1999. Root Cause Fa Failure ilure Anal Analysis, ysis, 6-13. Woburn, Massa Massachusetts: chusetts: Butterworth-Heinemann.

 

 

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Appendix A: Case Study A drill ship, drilling in deepwater GOM, abruptly lost communication with the downhole MWD/LWD/RSS suite. NPT cost in excess of a million dollars was incurred as the rig had to pull the BHA out of the hole. The RCFA/TAT identified this incident during the daily review of morning reports for GOM wells. The Drilling Engineer in charge of the well was contacted to discuss RCFA initiation, review the operating conditions surrounding the incident and determine the potential implications (on operations and cost) of the failure. The RCFA/TAT also contacted the vendor’s service coordinator to collect details of the failure and the MWD/LWD toolstring and to review the real-time attempts to re-establish communication with the tools. After gathering information about the failure incident and the tools involved, the RCFA/TAT sent notifications to Contracting and Procurement (C&P) and Quality Services to raise awareness to the incident and corresponding RCFA and to allow the necessary steps to be initiated for commercial resolution and for focused quality audits, as necessary. A third party engineer represented the RCFA/TAT RCFA/TAT during the initial phases of the disassembly/examination disassembly/examination of the toolstring. The failure was localized to the pulser of the MWD tool. Detailed examination of components in the pulser revealed that a guiding structure, designed to guide the pulser mechanism, was bent. Metallurgical examination of the guiding structure revealed fatigue cracks propagating from a geometric change in the guiding structure. These fatigue cracks caused the component to bend, resulting in high bending loads in the pulser mechanism. After this stage of analysis was complete, the vendor and the third party engineer provided teardown reports describing the findings/conclusions from the preliminary analysis to the RCFA/TAT. The RCFA/TAT organized a post-teardown meeting with the vendor to discuss the findings of the disassembly/analysis, operational history of the failed pulser, recent trends in pulser reliability, immedia immediate te corrective actions and recommendations, and the forward plan for the failure investigation. It was decided to critically review the design, material selection and QA/QC process for the guiding structure. Based on the information gathered during preliminary analysis and the postteardown meeting, the RCFA/TAT prepared a preliminary repor t and submitted it to the Well Delivery Team (WDT). The re port was also sent to technical experts and Engineering Team Leaders for the subject GOM operator. The incident was discussed in a weekly drilling network meeting so that other drilling engineers and operations superintendents would be aware of the failure and that an RCFA investigation was in progress. The information gathered during the investigation was also communicated in the quarterly RCFA Awareness Bulletin. The vendor’s engineering group conducted a review of the design and material used for the guiding structure. The RCFA/TAT also discussed the QA/QC procedures and replacement schedule of guiding mechanisms with the quality assurance group. The RCFA/TAT and vendor’s failure response focal point organized weekly teleconferences with the vendor’s engineering and quality assurance groups to discuss the progress/findings from each stage of the investigation. It was discovered that the design of the guiding structure contained an abrupt change in geometry, creating a location of stress concentration where the fatigue cracks initiated and propagated. The vendor agreed to modify the design to remove these abrupt changes in geometry. Discussions with the vendor’s quality assurance group revealed that the failed guiding structure was manufactured before the latest manufacturing upgrades for the guiding structure were implemented, making the component more susceptible to fatigue. Per the vendor’s QA/QC procedures, the guiding structure was visually inspected during pulser disassembly and was re-used (in the same or another pulser) if it passed the inspection process. The R CFA/TAT concluded that a visual examination would not be sufficient to detect fatigue cracks due to the size and geometry of the component. Based on the technical justification provided by the RCFA/TAT, the vendor agreed to modify the replacement procedure of the guiding structure. The vendor now replaces guiding structures with brand new ones during disassembly of the pulsers. The vendor agreed to the RCFA/TAT’s request to evaluate the design, inspection procedures a nd replacement schedule of components in the pulser assembly and other MWD/LWD tools that accumulate fatigue during normal operation of the tools. The vendor also agreed to the RCFA/TAT’s request to review the inventory of these components and discard any components that do not meet the acceptable design versions. The RCFA/TAT continued to receive regular updates as the vendor’s engineering and quality assurance groups conducted the design and inspection reviews. A failure response meeting was organized with the WDT, C&P, and the vendor to discuss the failure investigation, t he corrective actions, and the implementation plan for the corrective actions. The WDT informally agreed with corrective actions and the timeline for implementing these corrective actions. After the failure response meeting, the RCFA/TAT Lead Investigator authored a formal RCFA report containing the results of the investigation, the corrective actions and the timeline RCFA/TAT, the for implementation of the corrective actions. Following an internal review of the RCFA report within the RCFA/TAT,

 

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corrective actions and implementation plan documented in the report were sent to the vendor for review/approval. After obtaining the vendor’s approval, the RCFA report was sent to the WDT, technical experts and engineering team leaders in the GOM. After the WDT formally approved the RCFA report, the report was forwarded to RCFA teams operating in Asia-Pacific and Europe. These teams discussed the failure incident and the corrective actions with the respective vendor workshops in those regions, thus ensuring that the local workshops were aware of the corrective actions and implementation plan and would  provide suitable tools tools to the operator’s operator’s regional operations. The RCFA report was archived with the NPT event in the operator’s daily reporting system and was also published in the CFA/TAT’s ’s website. RCFA closeout notifications were sent to C&P, Quality Services and the vendor to formally close the R CFA/TAT investigation from a technical perspective, to facilitate closeout from a commercial perspective, and to focus follow-up quality audits.  

 

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Appendix B: Supporting Figures

Figure B-1: RCFA Report template

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Figure B-2: Risk Mitigation Report template template for a particular vendor and tool family

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Figure B-3: RCFA Awareness Bulletin Bulletin template

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