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Snubbing Operations IRP 15: Snubbing Operations An Industry Recommended Practice (IRP) for the Canadian Oil and Gas Industry Volume 15 - 2020 EDITION: 4 SANCTION DATE: February 2020 Operational Practices and Procedures IRP 15 Snubbing Operations Copyright/Right to Reproduce Copyright for this Industry Recommended Practice is held by Energy Safety Canada, 2020. All rights reserved. No part of this IRP may be reproduced, republished, redistributed, stored in a retrieval system, or transmitted unless the user references the copyright ownership of Energy Safety Canada. Disclaimer This IRP is a set of best practices and guidelines compiled by knowledgeable and experienced industry and government personnel. It is intended to provide the operator with general advice regarding the specific topic. It was developed under the auspices of the Drilling and Completions Committee (DACC). IRPs are provided for informational purposes. Users shall be fully responsible for consequences arising from their use of any IRP. The recommendations set out in this IRP are meant to allow flexibility and must be used in conjunction with competent technical judgment. It is recognized that any one practice or procedure may not be appropriate for all users and situations. It remains the responsibility of the user of this IRP to judge its suitability for a particular application and to employ sound business, scientific, engineering and safety judgment in using the information contained in this IRP. If there is any inconsistency or conflict between any of the recommended practices contained in this IRP and an applicable legislative or regulatory requirement, the legislative or regulatory requirement shall prevail. IRPs are by their nature intended to be applicable across industry, but each jurisdiction may have different or unique legal requirements. Users of this IRP should consult with authorities having jurisdiction. Users are advised to consider if their operations or practices and this IRP comply with the legal requirements in any particular jurisdiction in which they operate. Every effort has been made to ensure the accuracy and reliability of the data and recommendations contained in this IRP. However, DACC, its subcommittees, individual contributors and affiliated persons and entities make no representation, warranty, or guarantee, either express or implied, with respect to the accuracy, completeness, applicability or usefulness of the information contained in any IRP, and hereby disclaim liability or responsibility for loss or damage resulting from the use of this IRP, or for any violation of any legislative, regulatory or other legal requirements. IN NO EVENT SHALL DACC, ENERGY SAFETY CANADA, ANY SUBMITTING ORGANIZATION NOR ANY OF THEIR EMPLOYEES, DIRECTORS, OFFICERS, CONTRACTORS, CONSULTANTS, COMMITTEES, SUBCOMMITTEES, VOLUNTEERS, OR OTHER AFFILIATED OR PARTICIPATING PERSONS BE LIABLE TO OR RESPONSIBE FOR ANY PESON USING AN IRP OR ANY THIRD PARTY FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL OR CONSEQUENTIAL DAMAGES, INJURY, LOSS, COSTS OR EXPENSES, INCLUDING BUT NOT LIMITED TO LOST IRP 15 Snubbing Operations Operational Practices and Procedures REVENUE OR GOODWILL, BUSINESS INTERRUPTION, OR ANY OTHER COMMERCIAL OR ECONOMIC LOSS, WHETHER BASED IN CONTRACT, TORT (INCLUDING NEGLIGENCE) OR ANY OTHER THEORY OF LIABILITY. This exclusion shall apply even if DACC has been advised or should have known of such damages. Availability This document, as well as future revisions and additions, is available from Energy Safety Canada 150, 2 Smed Lane SE Calgary, AB T2C 4T5 Phone: 403.516.8000 Fax: 403.516.8166 Website: www.EnergySafetyCanada.com 4 February 2020 Operational Practices and Procedures IRP 15 Snubbing Operations Table of Contents 15.0.1 Purpose ....................................................................................................... 10 15.0.2 Audience ..................................................................................................... 10 15.0.3 Scope and Limitations ............................................................................... 10 15.0.4 Revision Process ....................................................................................... 10 15.0.5 Sanction ...................................................................................................... 11 15.0.6 Acknowledgements .................................................................................... 11 15.0.7 Range of Obligations ................................................................................. 11 15.0.8 Copyright Permissions .............................................................................. 12 15.0.9 Background ................................................................................................ 12 15.1 Snubbing Program ................................................................................. 14 15.1.1 Job Objectives ............................................................................................ 14 15.1.2 Well History ................................................................................................ 14 15.1.3 Risk Assessment ....................................................................................... 15 15.1.4 Emergency Response Plan (ERP) ............................................................. 16 15.1.5 Surface Equipment ..................................................................................... 16 15.1.6 Downhole Equipment ................................................................................. 17 15.1.7 Bottom hole Equipment ............................................................................. 17 15.1.8 Pre-Job Calculations .................................................................................. 20 15.1.8.1 Forces Acting on String ...................................................................... 21 15.1.8.2 Calculations Required ........................................................................ 21 15.1.9 Mitigation of Explosive Potential .............................................................. 22 15.1.9.1 Explosive Mixtures in the Casing ........................................................ 22 15.1.9.2 Explosive Mixtures in the Tubing ........................................................ 22 15.1.9.3 Surface Fires and Explosions ............................................................. 23 15.1.9.4 Other Reference Material ................................................................... 24 15.1.10 Snubbing Procedures ................................................................................ 24 15.1.11 Snubbing Vendor Selection ....................................................................... 25 15.1.12 Supervisory Control ................................................................................... 25 15.1.12.1 General Supervisory Control of Wellbore ........................................... 25 15.1.12.2 Specific Well Control Issues ............................................................... 25 15.1.12.3 Supportive Practices .......................................................................... 26 15.2 Downhole Equipment............................................................................. 27 15.2.1 Wireline Practices and Procedures ........................................................... 27 IRP 15 Snubbing Operations Operational Practices and Procedures 15.2.1.1 Wireline Practices............................................................................... 27 15.2.1.2 Wireline Plug Practices and Procedures ............................................. 27 15.2.3 Engineering Specifications ....................................................................... 30 15.2.4 Certification ................................................................................................ 30 15.3 Surface Equipment ................................................................................ 31 15.3.1 Requirements ............................................................................................. 31 15.3.1.1 Primary BOP Equipment .................................................................... 31 15.3.1.2 Auxiliary Wellhead Equipment ............................................................ 32 15.3.1.3 Snubbing Equipment .......................................................................... 32 15.3.1.4 Snubbing Unit Accumulator Requirements ......................................... 34 15.3.1.5 BOP Requirements for Rig-assisted Snubbing ................................... 34 15.3.1.6 BOP Requirements for Rigless Snubbing ........................................... 34 15.3.1.7 Lockout Equipment ............................................................................. 35 15.3.1.8 Reverse Circulation Sand Cleanout Equipment .................................. 36 15.3.2 Configuration .............................................................................................. 37 15.3.3 Engineering and Design Specifications ................................................... 39 15.3.4 Certification and Inspection ...................................................................... 39 15.3.4.1 CAODC Recommended Practices and Certifications ......................... 39 15.3.4.2 Snubbing Unit Pressure Containment Equipment ............................... 40 15.3.4.3 Hoisting Equipment ............................................................................ 41 15.3.4.4 Snubbing Unit Structure ....................................................................
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