GB/T 15054.1-2018Miniature screw threads - Part 1: Profiles, general plan and basic dimensions (English PDF)

Foreword

GB/T 15054 "Miniature screw threads" consists of two parts.

- Part 1. Profiles, general plan and basic dimension;

- Part 2. Tolerances and limits of size.

This Part is Part 1 of GB/T 15054.

This Part was drafted in accordance with the rules given in GB/T 1.1-2009. This Part replaces GB/T 15054.1-1994 "Miniature screw threads - Profiles", GB/T 15054.2-1994 "Miniature screw threads - General plan" and GB/T 15054.3-1994 "Miniature screw threads - Basic dimensions". Compared with GB/T 15054.1 ~ 15054.3-1994, the main technical deviations in this Part are as follows:

- deleted the arc radius Rmax requirements of external thread designed profile, root (see 3.2, 3.3 of GB/T 15054.1-1994);

- moved miniature screw threads of which the nominal diameter is 1mm and above AND basic dimensions into the annex (see Annex A, Clause 3 of GB/T 15054.2-1994 and Clause 4 of GB/T 15054.3-1994);

- deleted "thread code" (see Clause 4 of GB/T 15054.2-1994).

1 Scope

This Part of GB/T 15054 specifies the profiles, diameters of miniature screw threads as well as pitch general plan and basic dimensions.

This Part is applicable to miniature screw threads of general use of which the range of nominal diameter is 0.3mm~1.4mm.

NOTE: The profile and tolerance of miniature screw threads with a nominal diameter range of 1mm~1.4mm (S) differ from those of ordinary screw threads (M).

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 14791, The terms of screw threads

3 Terms and definitions

For the purposes of this document, the terms and definitions defined in GB/T 14791 apply.

4 Code

The following codes apply to this document.

D Basic large diameter of internal thread (nominal diameter)

D2 Basic medium diameter of internal thread

D1 Basic small diameter of internal thread

d Basic large diameter of external thread (nominal diameter)

d2 Basic medium diameter of external thread

d1 Basic small diameter of external thread (on basic profile)

d3 Root small diameter of external thread (on designed profile)

P Pitch […]