TR20_9 Preview

Building Engineering Services Association Installation and testing of:PART NINENATURALGAS TR/20 www.theBESA.com

Building Engineering Services AssociationInstallation and testing of: AcknowledgmentsPART NINE Members of the drafting panel who compiled this guide BESA wishes to record its sincere thanksNATURAL to the following members of the TR/20 draftingGAS Sub-Committee, without whose direct input of knowledge, time and experience this publication would not have been TR/20 produced. John StClair Eric Innes Cliff Toft Geoffrey Robinson Alan Keating – Secretary Frank J Ferris - Consultant BESA also wishes to acknowledge the input from BSRIA, CIBSE, IoP, IGEM, OFTEC, plus the remaining members of the Technical Committee for their time, input and vetting. ISBN 0-903783-48-7 First published 2003 ©2003 BESA BESA Publications Old Mansion House Eamont Bridge Penrith CA10 2BX 01768 860405 [email protected]. www.theBESA.com

Building Engineering Services AssociationInstallation and testing of: ForewordPART NINE TR/20 is published against a background of significant change within the building services engineering sectorNATURAL over recent years. Of particular note has been theGAS industry wide campaign to raise standards and performance through the Construction Best Practice TR/20 Programme. Much effort has been and continues to be made to raise the productivity, performance and competence standards of our sector. To support this programme BESA has undertaken to provide a number of measures designed to demonstrate and achieve positive differentiation of their members. One such measure has been to undertake a fundamental review of TR/10, the previous BESA standard for Installation work ‘Heating Hot and Cold Water Supply’. As a result of this review TR/20 replaces TR/10 and emerges as a new standard for ‘The Installation and Testing of Pipework Services’ for the building services engi- neering sector. It embraces a comprehensive range of pipework services and is structured as a set of 10 ‘stand alone’ sectionalised specifications. The objective of TR/20 is to provide a pipework installation specification that will ensure compliance with accepted good practice. It is intended that this standard specification will be used generally as a means of measurement and assessment of a contractor’s performance and, specifically, to demonstrate compliance and competence under the BESA Inspection and Assessment arrangements. It is envisaged that TR/20 be used either in the absence of a client specification or by specific reference as an integral part of such a specification. It is also proposed that TR/20 be used as a quality benchmark whereby any shortfall identified within an alternative specification is drawn to the client’s attention. Unlike its forerunner, TR/20 does not address design or commissioning requirements. These are considered to be very ably addressed by other industry documents already in place published by CIBSE, BSRIA, OFTEC and others, for which appropriate references are provided. TR/20 also excludes equipment incorporated within or connected to the pipework installation. The specification and selection of equipment is considered to be a responsibility of the system designer who should ensure that where appropriate the selection is compliant with the client’s brief. Additionally, it is not the policy of BESA to promote any particular product or manufacturer. During the review and drafting process the drafting Sub-committee has consulted widely with individuals and external organisations to ensure that the new standard fully reflects the industry’s current good practice. The resulting publication will, I believe, serve as a recognised benchmark for our industry sector and BESA members in particular. I take this opportunity to thank all who have contributed to its production and in particular the members of the TR/20 Sub-committee for their tireless efforts and collective contribution of invaluable knowledge and experience. John Hunt Former Chairman, BRSA Technical Committee www.theBESA.com

Installation and Testing of Pipework Systems Part Nine – Natural GasCONTENTSSection 1 INTRODUCTION Page1.0 FOREWORD 71.1 OBJECTIVE 71.2 STANDARD OF WORKMANSHIP 71.3 QUALITY ASSURANCE 81.4 SCOPE 81.5 PUBLICATION AND REVIEW 81.6 OPERATING CONDITIONS 81.7 DESCRIPTION OF SERVICE 81.8 FLOW REQUIREMENTS 8 9Section 2 MATERIALS AND JOINTING METHODS 92.1 PIPING MATERIALS 112.2 SELECTION (TABLES “A & B”) 112.3 STEEL PIPE JOINTING 11 2.3.1 Threaded Assembly 112.4 2.3.2 Welded Assembly 11 2.3.3 Welding Methods 112.5 2.3.4 Flanged Assembly 112.6 COPPER PIPE JOINTING 122.7 2.4.1 Compression Joints 12 2.4.2 Capillary Joints 12 2.4.3 Brazed Joints 12 PUSH FIT JOINTING 12 PRESS FIT JOINTING 13 PROPRIETARY SYSTEMS 13 13Section 3 CONSTRUCTION AND ASSEMBLY OF STEEL PIPEWORK 133.1 PIPING MATERIAL DETAILS 133.2 3.1.1 Pipe Finish 13 THREADED ASSEMBLY 133.3 3.2.1 Threaded Joints 14 3.2.2 Bends and Fittings 143.4 WELDED ASSEMBLY 143.5 3.3.1 Welding Methods (TABLE “B”) 143.6 3.3.2 Welding Fittings 153.7 FLANGED ASSEMBLY 163.8 PRESS FIT ASSEMBLY SUPPORT AND FIXINGS 16 3.6.1 Pipework Support Centres (TABLE “C”) 16 EXPANSION AND CONTRACTION 17 3.7.1 Natural Flexibility 17 PIPE SLEEVES 17 17Section 4 CONSTRUCTION AND ASSEMBLY OF COPPER PIPEWORK 174.1 PIPING MATERIAL DETAILS 174.2 4.1.1 Pipe Finish 17 COMPRESSION JOINT AND FITTING ASSEMBLY 174.3 4.2.1 Compression Method 18 4.2.2 Compression Fittings 184.4 CAPILLARY JOINT AND FITTING ASSEMBLY 184.5 4.3.1 Capillary Method 18 4.3.2 Capillary Fittings FLANGED JOINT AND FITTING ASSEMBLY BRAZED JOINT AND FITTING ASSEMBLY 4.5.1 Brazing Method 4.5.2 Brazing Fittings4

Installation and Testing of Pipework Systems Part Nine – Natural Gas4.6 PUSH FIT JOINT AND FITTING ASSEMBLY Page 4.6.1 Push Fit Method 184.7 4.6.2 Push Fit Fittings 18 PRESS FIT JOINT AND FITTING ASSEMBLY 184.8 4.7.1 Press Fit Method 184.9 4.7.2 Press Fit Fittings 184.10 PULLED BENDS 19 SUPPORT AND FIXINGS 19 4.9.1 Pipework Support Centres (TABLE “D”) 19 EXPANSION AND CONTRACTION 19 4.10.1 Expansion Devices 19 4.10.2 Anchors and Guides 20 4.10.3 Cold Draw 20 20Section 5 STAINLESS STEEL PIPEWORK CONSTRUCTION AND ASSEMBLY 21Section 6 POLYETHYLENE PIPEWORK CONSTRUCTION AND ASSEMBLY 216.1 216.2 PLASTIC INTRODUCTION 216.3 PIPEWORK APPLICATION SELECTION 21 JOINTING METHODS 226.4 6.3.1 Flanged 226.5 6.3.2 Thermal Fusion 226.6 6.3.3 Butt-Welding 226.7 6.3.4 Socket Welding 226.8 6.3.5 Electrofusion 22 6.3.6 Compression 23 INSTALLATION 23 EXPANSION AND CONTRACTION RATES 23 ULTRA-VIOLET (UV) 23 MIXING OF PIPE AND FITTINGS HANDLING 24 24Section 7 GENERAL INSTALLATION REQUIREMENTS 247.1 247.2 LOCATION 247.3 EQUIPOTENTIAL BONDING 247.4 OXYGEN ENRICHMENT 247.5 BLAST BURNERS 247.6 OVERPRESSURE PROTECTION 247.7 EXPANSION AND CONTRACTION 257.8 FATIGUE 257.9 VENT PIPEWORK 257.10 VENTILATION AND DUCTS 257.11 LABORATORY AND SIMILAR APPLICATIONS 257.12 PROTECTION 257.13 GAS SAFETY LINE DIAGRAM 267.14 WARNING NOTICES 26 SYSTEM CLEANLINESS 267.15 7.14.1 Delivery and Storage 26 7.14.2 Construction 277.16 7.14.3 Pipe Sleeves 277.17 7.14.4 Testing 27 BURIED PIPEWORK 27 7.15.1 Minimum Depth of Cover 7.15.2 Minimum Distances 27 SPACING AND CLEARANCE 27 ALIGNMENTSection 8 ACCESSORIES AND PIPELINE ANCILLARIES8.1 SCOPE 8.1.1 General 5

Installation and Testing of Pipework Systems Part Nine – Natural Gas8.2 VALVES 278.3 ISOLATION 288.4 IDENTIFICATION 288.5 GAS BOOSTERS 288.6 TEST AND PURGE POINTS 288.7 FLEXIBLE HOSES 28 29Section 9 TESTING AND PURGING 299.1 SOUNDNESS 299.2 SOUNDNESS TESTING (DROP TEST) 299.3 LET-BY TEST 299.4 PURGING 309.5 REVISIONS TO STANDARDS 30 30Section 10 THERMAL INSULATION 30 3010.1 APPLICATION 30 31 10.1.1 Installation Considerations 31 TRACE HEATING 3110.2 31 32 10.2.1 Pre-Installation Guidelines 32 10.2.2 Installation 32 10.2.3 Heating Cable Connections 33 10.2.4 Heating Cable TestingSection 11 BIBLIOGRAPHY AND SOURCES11.1 LEGISLATION11.2 ACoPS AND GUIDANCE NOTES11.3 BRITISH STANDARDS11.4 UTILISATION PROCEDURES11.5 BESA PUBLICATIONS11.6 MISCELLANEOUS11.7 ABBREVIATIONS6