ASME B1.20.1 2013 R2018
$98.04
ASME B1.20.1 – 2013: Pipe Threads, General Purpose, Inch – Reaffirmed 2018
| Published By | Publication Date | Number of Pages |
| ASME | 2013 | 40 |
ASME’s widely-referenced B1.20.1 Standard on Pipe Threads, General Purpose, Inch covers dimensions and gaging of the world’s most common pipe threads: NPT, NPSC, NPTR, NPSM, and NPSL. From critical applications demanding robustness and precision to common plumbing and hardware, these threads are used everywhere in the United States and abroad. This long awaited revision incorporates both subtle and substantive changes, including: Moving of the gaging point of reference of external threads in certain circumstances; A new acceptability section for instances of gaging disputes; A change to parameters, facilitating the calibration of working gages; Guidance for plated or coated pipe threads; Better explanatory language for the lay-user. This is the foundational Standard for NPT, NPSC, NPSM, and NPSL pipe threads. All companies that manufacture, sell, or use these threads should have this revision in their technical library.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 5 | CONTENTS |
| 6 | FOREWORD |
| 7 | COMMITTEE ROSTER |
| 8 | CORRESPONDENCE WITH THE B1 COMMITTEE |
| 9 | 1 INTRODUCTION 1.1 Scope 1.2 Related Standard 1.3 Thread Designations 1.3.1 1.3.2 1.4 Sealing NPT and NPSC Only 1.4.1 Mating Threads. 1.4.2 Sealant. 1.4.3 Tightening Torque. 1.4.4 Other Considerations. 1.4.5 Pressure-Tight Threads Without Sealant. 1.5 Appendices |
| 10 | 1.6 Referenced Standards 1.7 Terminology 2 AMERICAN NATIONAL STANDARD PIPE THREAD FORM 2.1 Thread Form 2.2 Angle of Thread 2.3 Thread Height Figures Fig. 1 Root, Crest, and Flank Engagement, NPT |
| 11 | Fig. 2 Basic Form of American National Standard Taper Pipe Thread, NPT |
| 12 | 2.4 Thread Truncation 3 SPECIFICATION FOR TAPER PIPE THREADS, NPT 3.1 General 3.1.1 Notation. 3.1.2 Symbols. 3.1.3 Handling Considerations. 3.1.4 Form of Thread. 3.1.5 Taper of Thread. 3.1.6 Pitch Diameters of Thread. 3.1.7 Length of Effective Thread. |
| 13 | Tables Table 1 Limits on Crest and Root Truncation of American National Standard External and Internal Taper Pipe Threads, NPT |
| 14 | Fig. 3 American National Standard Taper Pipe Thread Notation |
| 15 | 3.1.8 Hand-Tight Engagement Between External and Internal Taper Threads. 3.1.9 Wrench-Tight Engagement Between External and Internal Taper Threads. 3.1.9.1 Thread Engagement Considerations. 3.1.9.2 Special Applications. 3.1.10 Tolerances on Product Taper, Lead, and Angle. 3.1.11 Basic Dimensions. 3.2 Gaging NPT Threads 3.2.1 External Thread Gaging 3.2.1.1 L1 Ring Gage. 3.2.1.2 External L1-Indicating Gage. 3.2.2 Internal Thread Gaging 3.2.2.1 L1 Plug Gage. 3.2.2.2 Internal L1-Indicating Gage. 3.2.3 Nicked Threads. 3.2.4 Treatment of Chamfers, Recesses, Counterbores. |
| 16 | Table 2 Basic Dimensions of American National Standard Taper Pipe Thread, NPT |
| 18 | Fig. 4 Gaging External Taper Threads With L1 Ring Gage Table 3 Tolerances on Taper, Lead, and Angle of Pipe Threads, NPT |
| 19 | Fig. 5 Gaging of Chamfered Threads |
| 20 | 3.2.4.1 3.2.4.2 3.2.4.3 3.2.4.4 3.2.4.5 3.2.5 Acceptance of Product Made Prior to This Revision. 3.2.6 Coated Threads. 3.2.6.1 Coating Buildup. Fig. 6 Gaging Internal Taper Threads With L1 Plug Gage |
| 21 | 3.2.6.2 Precoating Gaging Standoff Compensation, Internal Thread. 3.2.6.3 Precoating Gaging Standoff Compensation, External Thread. 3.2.6.4 Precoating Gages. 3.2.7 Supplemental Gaging 3.3 Acceptability 4 SPECIFICATIONS FOR INTERNAL STRAIGHT THREADS IN PIPE COUPLINGS, NPSC 4.1 Pressure-Tight Internal Straight Pipe Threads |
| 22 | 4.1.1 Thread Designation. 4.1.2 Dimensions and Limits of Size. 4.2 Gaging NPSC Internal Threads 4.2.1 L1 Plug Gage. 4.2.2 L1 Internal Indicating Gage. 5 SPECIFICATIONS FOR RAILING JOINT TAPER PIPE THREADS, NPTR 5.1 Railing Joints 5.1.1 Thread Designation. 5.1.2 Form of Thread. 5.2 Gaging and Tolerances, NPTR Table 4 Dimensions, Internal Straight Threads in Pipe Coupling, NPSC |
| 23 | Table 5 Dimensions of External and Internal Taper Pipe Threads for Railing Joints, NPTR |
| 24 | 6 SPECIFICATIONS FOR STRAIGHT PIPE THREADS FOR MECHANICAL JOINTS; NPSM, NPSL 6.1 Straight Pipe Threads for Mechanical Joints 6.1.1 Thread Designations. 6.1.2 Pitch and Flank Angle. 6.1.3 Diameter of Thread. 6.2 Free-Fitting Mechanical Joints for Fixtures, NPSM 6.3 Loose-Fitting Mechanical Joints With Locknuts, NPSL 6.4 Gaging for NPSM and NPSL Threads 6.4.1 GO Gaging. 6.4.2 NOT GO Gaging. 6.4.3 Indicating Gages. 6.4.4 Gage Dimensions. |
| 25 | Table 6 Dimensions of External and Internal Straight Pipe Threads for Fixtures, NPSM |
| 26 | Table 7 Dimensions, External and Internal Straight Pipe Thread for Locknut Connections, NPSL |
| 27 | 7 GAGES AND GAGE TOLERANCES FOR AMERICAN NATIONAL STANDARD TAPER PIPE THREADS, NPT 7.1 Gage Design 7.1.1 Gages for External Threads. 7.1.2 Gages for Internal Threads. 7.1.3 Partial End Threads. 7.1.4 Marking of Gages. 7.2 Master Gages 7.2.1 Master Gage Tolerances. 7.3 Working Gages 7.3.1 Working Gage Tolerances. 7.4 Relation of Lead and Angle Variations to Pitch Diameter Tolerances of Gages |
| 28 | Fig. 7 NPT Standard Taper Pipe Thread Plug and Ring Gages |
| 29 | Fig. 8 Suggested Form of Gage Thread |
| 30 | Table 8 Basic Dimensions of Threaded Gages for American National Standard Taper Pipe Threads, NPT |
| 31 | Table 9 Working Gage Tolerances for American National Standard Taper Pipe Thread, NPT |
| 33 | Table 10 Diameter Equivalent of Variation in Half Included Angle of Thread for Tools and Gages |
| 34 | Table 11 Diameter Equivalent of Variation in Lead for Tools and Gages |
| 35 | NONMANDATORY APPENDIX A THE TURNS OF ENGAGEMENT METHOD OF GAGING PRODUCT THREADS A-1 METHOD OF GAGING A-2 TOLERANCE |
| 36 | NONMANDATORY APPENDIX B TAP DRILL SIZES |
| 37 | NONMANDATORY APPENDIX C THREAD TYPES AND CORRESPONDING GAGES AND GAGING |
