DIMENSIONS FOR #0000, #000 AND #00 THREADS

Dimensions for unified thread sizes of #0000, #000 and #00 are given in the Appendix-5 of ASME B18.6.3 and summarized in the following chart.

Nominal Size and Threads per inch Series Designation Class Major Diameter Pitch Diameter Minor Diameter
Allowance Max. Min. Max. Min. Tol.
0000-160 NS 2 0.0000 0.0210 0.0195 0.0169 0.0158 0.0011 0.0128
000-120 NS 2 0.0000 0.0340 0.0325 0.0286 0.0272 0.0014 0.0232
00-90 NS 2 0.0000 0.0470 0.0450 0.0398 0.0382 0.0016 0.0326
00-96 NS 2 0.0000 0.0470 0.0450 0.0402 0.0386 0.0016 0.0334
EXTERNAL THREAD

Nominal Size and Threads per inch Series Designation Class Minor Diameter Pitch Diameter Major Diameter, Min
Min. Max. Min. Max. Tol.
0000-160 NS 2 --- --- 0.0169 0.0181 0.0012 0.0210
000-120 NS 2 --- --- 0.0286 0.0300 0.0014 0.0340
00-90 NS 2 --- --- 0.0398 0.0414 0.0016 0.0470
00-96 NS 2 --- --- 0.0402 0.0418 0.0016 0.0470
INTERNAL THREAD

Note: The minor diameter limits for internal threads are not specified; they are determined by the amount of thread engagement necessary to satisfy the strength and tapping performance in the intended application.

Reference:

  • ASME B18.6.3 - 2003, Machine Screws and Machine Screw Nuts