Heat Treatment and Testing of Carbon and Low Alloy Steel Large Cross Section and Critical Section Components

API RECOMMENDED PRACTICE 6HT SECOND EDITION, JUNE 2013

REAFFIRMED, NOVEMBER 2018

Special Notes

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Copyright © 2013 American Petroleum Institute

Foreword

This recommended practice was formulated by Subcommittee 6, Ad-Hoc Task Group under ISO Standard 10423 on Heat Treatment of Large Cross Section and Critical Section Components. It is a report of the conclusion of a task group study of heat treatment as covered by API Specification 6A, Specification for Wellhead and Christmas Tree Equipment.

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Contents

Page

1. Scope 1

2. Normative References 1

3. Terms and Definitions 1

4. Purpose 2

5. Application 2

6. Recommended Heat Treating Practices 2

   1. General 2

   2. Requirements for Heat Treating Equipment 3

   3. Recommendations for Heat Treatment Procedures and Practices 5

   4. Recommendations for QTCs 9

7. Design Consideration and Material Selection Requirements 9

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