What We Do / QC-FIT Connector and Bolts failure

QC-FIT Connector and Bolts failure

During drilling operations in the Gulf of Mexico region, a gas kick occurred in which the casing, cement and liner top seal assembly failed resulting in a loss of well control. The elastomeric based liner top seal assembly may not have been qualified for exposure to high operating temperatures and gas exposure.  The QC-FIT evaluated the QA/QC “fit for service” concerns for liner seal assembly and cementing failures.  Concerns with equipment (seal) “fitness for service” use for operational conditions, appropriate material selection, and with equipment test protocol verification and validation conditions. Current industry practices and BSEE regulations for pressure testing may not be sufficient to evaluate the integrity of the seal assembly and/or the cement column. Currently both barriers are not independently pressure tested, therefore the dual barrier system is tested as a whole. The performance rating of down-hole equipment may not be clearly communicated or understood between operators and manufacturers globally.

Key Findings and Recommendations

• Existing industry practices and BSEE regulations related to pressure testing may not be adequate to evaluate the integrity of either the seal assembly or the cement column. BSEE should consider modifying its regulations to ensure that the integrity of these barriers can be verified after installation.

• Operators should be required to verify that any pressure containing equipment installed down-hole has been designed, tested, and rated for any potential loss of well control condition to which it might be exposed during its service life.

• A comprehensive analysis of well designs utilizing shallow liners and sub mud-line casing hangers needs to be performed by either BSEE or the industry to ensure that best engineering practices are being utilized to minimize the risk of a loss of well control event.

QC-FIT Seal Assemblies and Cement Failures can be accessed by the following link on BSEE’s website.

QC-FIT Fastener Failures

Failed studs (connectors) were identified during an in-between well maintenance inspection on the LMRP of a BOP. The failed connectors’ material hardness was out of the manufacturer’s material design specification.  An unapproved, sub-contracted third-tier vendor did not follow the manufacturer’s heat treatment procedure.

This QC-FIT evaluated QA/QC concerns of fastener failures on the connector on a BOP collet connector flange.  Several QA/QC issues were identified throughout the manufacturing process with second and third tier sub-contracted vendors. QA/QC manufacturing oversights resulted in the improper heat treatment and raw material orders for several lots of fasteners.  This process breakdown affected the material properties (hardness) which led to issues with the bolts for effective subsea operation.

Key Findings and Recommendations

• Existing industry practices and BSEE regulations related to QA/QC and quality management systems may not be adequate to ensure that critical components are manufactured as fit for service at all levels of the manufacturing supply chain. BSEE should consider modifying its regulations to ensure that the integrity of all critical components can be verified throughout the manufacturer’s supply chain.

• The failure mechanism of subsea fasteners is not fully understood. Industry and/or BSEE should perform scientific studies to test the conditions fasteners are exposed to in subsea service, in order to better understand and predict the failure modes of fasteners.

• A comprehensive analysis of industry standards and best industry practices regarding the manufacture and service conditions of fasteners for use in subsea environments around the world needs to be performed by either BSEE or the industry, in order to minimize the risk of a loss of well control event.

• Standards development organizations should collaborate on developing consistent global standards, based on scientific evidence and best practices, for material property requirements regarding fasteners.

Submitting Research Proposals


SRS team members serve as subject matter experts (SME) and Contracting Officer Representatives (COR) for Technical Proposal Evaluation Committees (TPEC) for research contracts in areas such as:

• Materials and Corrosion

• Subsea Fasteners

• Safety of Oil and Gas Operations in the Outer Continental Shelf

• High Temperature High Pressure (HPHT) Material Evaluations

• Liner and Casing seals

• Cementing

• Effect of H2S and CO2 in HPHT Wells on Tubulars and Cement


SRS team members continuously engage with industry standards organizations to help improve safety, equipment reliability, and environmental protection in the OCS. SRS team members are active in several boards and committees as non-voting members in organizations such as API, ASME, ANSI, ASTM, NACE, AWS, etc.  The SRS role is to help identify significant manufacturing, processing, design and requirements concerns, and equipment performance issues, fit for service, operational environment, and optimal material design requirements for OCS equipment.

SRS assists the Regulations and Standards Branch (RSB) by serving as BSEE representatives and as technical SMEs for the following API Committees meetings.  SRS members also reviewed, provided technical comments of concern on the draft API documents.

• API 11D1 – Packers and Bridge Plugs

• API 14A – Specification for Subsurface Safety Valves

• API 16F – Specification for  Marine Drilling Equipment

• API 16Q – Recommended Practice for Design, Selection, Operation and Maintenance of Drilling Riser Systems

• API 16R – Specification for Marine Drilling Riser Couplings

• API17TR8 – High-Pressure High-Temperature Design Guidelines

• API 19LH – Liner Hangers

• API Q1  – Specification for Quality Management System Requirements for Manufacturing Organizations for the Petroleum and Natural Gas Industry

• API Q2 – Specification for Quality Management System Requirements for Service Supply Organizations for the Petroleum and Natural Gas Industry

• API 18 – Life Cycle Management (LCM)

• API 6A718 – Nickel Base Alloy 718 (UNS N07718) for Oil and Gas Drilling and Production Equipment

• 2014 API Summer Standards Meeting, Chicago, IL

• 2014 API Winter Standards Meeting, Dallas, TX

• API Subcommittee 6 – Valves and Wellhead Equipment

• API 6A- Specification for Wellhead and Christmas Tree Equipment

• API RP 6HT – Recommended Practice for Heat Treatment and Testing of Carbon and Low Alloy Steel Large Cross Section and Critical Section Components

• API CSOEM - Committee on Standardization of Oilfield Equipment and Materials

• API SC 5 – Subcommittee on Tubular Goods

• API SC 20 – Subcommittee on Supply Chain

• ASME Boiler Pressure Vessel Code Section VIII Division 2 and 3

• NACE MR0175 – Metals for Sulfide Stress Cracking and Stress Corrosion Cracking Resistances in Sour    

• Oilfield Environments

• SRS participates in wind energy standards meetings with RSB.

Performed standards review of ISO, ASTM, API, NORSOK, and NACE standards identified inconsistency in material properties (e.g. hardness, ultimate tensile strength,yield strength) requirement gaps for subsea application material property requirements.

Technical Evaluations (QC-FIT Reports)

Quality Control - Failure Incident Team (QC-FIT) technical evaluations are conducted when BSEE determines that a piece of equipment or system(s) used for oil and gas operations offshore could fail to perform safely. SRS/QC-FIT technical evaluations focus on identifying quality assurance (QA)/quality control (QC) concerns for a piece of equipment or system which affects its performance reliability resulting in an impact on the safety of oil and gas operations and environment protection on the Outer Continental Shelf (OCS). QC-FIT technical evaluations are distinct from District Form 2010 Incident Investigations or Regional Panel Investigations which focus on field operational procedures, regulatory compliance, plans and permits.  

QC-FIT Evaluation of Seal Assemblies and Cement Failures

Bolt Failures

Safety & Engineering Alerts

Safety Alert: Connector and Bolt FailuresFebruary 2, 2016

5,000 psi Blind Shear Ram Bolting Torque Engineering Bulletin (posted with permission from GE) January 16, 2016Correspondence

BSEE SA 318 Industry Response Final Presented This was submitted to BSEE by API on March 31, 2015. BSEE staff are currently reviewing this documents

API Response to Director Salerno March 14, 2016

API Response to Director Salerno February 5, 2016

Director's Letter to API January 22, 2016

BSEE Director's Response Letter August 8, 2014

Letter of Transmittal on Connector and Bolt Failures July 28, 2014