Thermoplastic Piping Systems

ASME Standards for Nonmetallic Pressure Piping Systems

AN A MERICAN NA TIONAL S T AND ARD

ASME NM.1-2020

(Revision of ASME NM.1-2018)

ASME NM.1-2020

(Revision of ASME NM.1-2018)

Thermoplastic

Piping Systems

ASME Standards for Nonmetallic Pressure Piping Systems

AN AMERICAN NATIONAL STANDARD

Two Park Avenue • New York, NY • 10016 USA

Date of Issuance: December 31, 2020

The next edition of this Standard is scheduled for publication in 2022. This Standard will become effective 6 months after the Date of Issuance.

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CONTENTS

Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii

Committee Roster . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii

Correspondence With the NPPS Committee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii

Summary of Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvi

7-7 Inspection, Examination, and Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

Chapter 8 Multilayered Reinforced Thermoplastic Piping Systems . . . . . . . . . . . . . . . . . . . . . 90

8-1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

8-2 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

8-3 Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

8-4 Fabrication, Assembly, and Erection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

8-5 Examination, Inspection, and Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

Mandatory Appendices

I Fusing and Electrofusing of Polyamide-11 Thermoplastic Piping; and Fusing of Polypropylene, Poly(Vinylidene Fluoride), and Poly(Tetrafluoroethylene) Plastic Liners

of Lined Steel Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

II Threaded Thermoplastic Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

1. Acceptance Criteria for Thermoplastic Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

2. Stress Intensification Factors and Flexibility Factors . . . . . . . . . . . . . . . . . . . . . . . . . . 118

   V One-Piece Thermoplastic Flanges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

   Nonmandatory Appendices

   
   

   A	Components for Thermoplastic Lap-Joint Flange Connections . . . . . . . . . . . . . . . . . . . .	127
   B	Design Requirements for Buried Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	149
   C	Pressure Surge From Fluid Transient . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	158
   D	Multilayered Reinforced Thermoplastic Piping System(s) Operation, Maintenance, and Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	160
   Figures
   2-3.2.2-1	Nomenclature for 90-deg Mitered Elbows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	16
   2-3.2.4-1	Tapered Transition Joint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	18
   5-1.11-1	Fusion Positions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	39
   5-1.11-2	Fusion Test Positions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	40
   5-2.6-1	Heat Fusion Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	43
   5-2.6.1-1	Required Minimum Melt Bead Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	44
   5-2.8.1.1-1	Cross Section of Upset Beads for Butt-Fused Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . .	47
   5-2.8.1.1-2	Cross Section of Upset Beads for Sidewall-Fused Fitting (Profile at Crotch of Fitting) . .	48
   5-2.8.1.3-1	Bend Test Specimen Removal, Configurations, and Testing . . . . . . . . . . . . . . . . . . . . . .	51
   5-2.8.1.3-2	Electrofusion Bend Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	53
   5-2.8.1.4-1	HSTIT Specimen Configuration and Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	54
   5-2.8.1.4-2	HSTIT Specimen Failure Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	55
   5-2.8.1.4-3	Electrofusion Peel Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	56
   5-2.8.1.4-4	Short-Term Hydrostatic Test Specimen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	57
   5-3.5-1	Solvent Fusion Joint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	63
   5-3.6.2-1	Solvent Fusion Specimens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	66
   7-4.4.4.4-1	Stress Range Factor, f . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	78
   I-7.7-1	Instruction on Preparing and Cutting Electrofusion Coupling for Crush Test . . . . . . . . .	99
   I-7.8-1	Joint Crush Specimens in Vise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	100
   I-8.2-1	Polyethylene Pipe Butt-Fusion Joint O.D. Bead (Cross-Sectional View) . . . . . . . . . . . . . .	103
   I-9.1-1	Cross-Sectional View of PA-11 Butt-Fusion Bead . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	104

   
   

   I-9.2-1	Cross-Sectional View of an Electrofusion Coupling . . . . . . . . . . . . . . . . . . . . . . . . . . . .	105
   I-9.2-2	Fit-Up Gap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	105
   I-9.3-1	Cross-Sectional View of a PP and PVDF Butt-Fusion Liner Bead Formed Against the Heater Plate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	107
   III-3-1	Solvent-Cement-Weld Shrink-Back Appearance (Cross-Sectional View) . . . . . . . . . . . . .	117
   V-1.1-1	Socket Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	124
   V-1.2-1	Threaded Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	124
   V-2.3-1	One-Piece Thermoplastic Flange With Reinforcing Rings . . . . . . . . . . . . . . . . . . . . . . .	124
   A-2.3-1	Contact Area Between Flange Adapter and Backup Ring . . . . . . . . . . . . . . . . . . . . . . .	131
   A-2.3-2	Plate Flange Adapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	131
   A-2.3-3	Convoluted Backup Ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	131
   A-4.3.1-1	Thermoplastic Flange Adapter — Typical for PE, PP, and PVDF Butt-Fused Lap-Joint Flange Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	138
   A-4.3.2-1	Typical ISO or DVS Metric Spigot Socket-Fusion Flange Adapters . . . . . . . . . . . . . . . . .	139
   A-4.3.2-2	Typical ISO or DVS Metric Flange Adapters for Socket Fusing . . . . . . . . . . . . . . . . . . .	140
   A-4.3.2-3	Special ISO or DVS Metric Butt-Fusion Flange Adapter for Higher-Pressure Connections	141
   A-5.2-1	Transistor Flange Arrangement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	144
   A-5.2-2	Solid PVDF Flange and Backup Ring to Thermoplastic-Lined Metal Pipe . . . . . . . . . . . .	145
   A-5.3-1	One-Piece Flange . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	145
   A-5.3-2	Flange Adapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	145
   A-9.4-1	Drawings for Bolts With Nuts and Stud Bolts With Nuts . . . . . . . . . . . . . . . . . . . . . . .	148
   Tables
   1-4-1	Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	8
   1-5-1	Status of Appendices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	9
   2-3.2.2-1	Geometric Shape Rating (GSR) for HDPE Fittings . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	15
   2-3.2.2-2	Design Factor (DF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .