1 - AS 2181, PART 3-1981 SCREWING TAPS - INCH SERIES SCREW THREADS
4 - PREFACE
5 - CONTENTS
6 - SECTION 1. SCOPE AND GENERAL
6 - 1.1 SCOPE.
6 - 1.2 TERMS AND DEFINITIONS.
6 - 1.2.1 Terminology of the Thread Profiles.
6 - 1.2.2 General Terminology of Taps.
7 - 1.2.3 Terminology of Cutting Features.
10 - 1.3 MATERIALS.
10 - 1.4 HEAT TREATMENT.
10 - 1.5 MARKING.
11 - SECTION 2. GENERAL DIMENSIONS OF TAPS
11 - 2.1 SCOPE OF SECTION.
11 - 2.2 GENERAL DIMENSIONS OF STANDARD MACHINE AND HAND TAPS.
14 - SECTION 3. SCREW THREAD LIMITS AND TOLERANCES FOR UNIFIED SERIES TAPS
14 - 3.1 SCOPE OF SECTION.
14 - 3.2 GROUND THREAD TAPS.
14 - 3.2.1 Tap Classes.
14 - 3.2.2 Tap Major Diameter.
14 - 3.2.3 Tap Pitch Diameter.
14 - 3.2.4 Tap Minor Diameter.
14 - 3.2.5 Tolerance on Pitch.
14 - 3.2.6 Tolerance on Thread Angle.
14 - 3.2.7 Runout.
14 - 3.3 CUT THREAD TAPS.
14 - 3.3.1 Tap Class.
14 - 3.3.2 Tap Major Diameter.
14 - 3.3.3 Tap Pitch Diameter.
14 - 3.3.4 Tap Minor Diameter.
15 - 3.3.5 Tolerance on Pitch.
15 - 3.3.6 Tolerance on Thread Angle.
15 - 3.3.7 Runout.
26 - SECTION 4. SCREW THREAD LIMITS AND TOLERANCES FOR BSW, BSF AND BA TAPS
26 - 4.1 SCOPE OF SECTION.
26 - 4.2 GROUND THREAD TAPS.
26 - 4.2.1 Tap Classes.
26 - 4.2.2 Tap Major Diameter.
26 - 4.2.3 Tap Pitch Diameter.
26 - 4.2.4 Tap Minor Diameter.
26 - 4.2.5 Tolerance on Pitch.
26 - 4.2.6 Tolerance on Thread Angle.
26 - 4.2.7 Runout.
26 - 4.3 CUT THREAD TAPS.
26 - 4.3.1 Tap Class.
26 - 4.3.2 Tap Major Diameter.
26 - 4.3.3 Tap Pitch Diameter.
26 - 4.3.4 Tap Minor Diameter.
27 - 4.3.5 Tolerance on Pitch.
27 - 4.3.6 Tolerance on Thread Angle.
27 - 4.3.7 Runout.
37 - APPENDIX A - NOTES ON CUMULATIVE PITCH ERROR
38 - APPENDIX B - VALUES OF ELEMENTS FOR USE IN THE BASIC FORMULAS FOR TAPS
43 - APPENDIX C - BASIS OF TOLERANCES FOR MACHINE AND HAND TAP BLANKS
43 - C1 SCOPE.
43 - C2 MANUFACTURING TOLERANCES.
44 - APPENDIX D - SIZES OF INCH SERIES TAP BLANKS
46 - APPENDIX E - DESIGNATION FOR THE PURPOSE OF AN ENQUIRY OR ORDER