GB/T 12359-2008Metric trapezoidal screw threads - Limits of sizes (English PDF)

Foreword

This standard replaces GB/T 12359-1990 "trapezoidal thread size limit." This standard compared with GB/T 12359-1990, deleted 7h external thread tolerance, thread size can according to GB/T 5796.2-2005 The provisions were part of a series of adjustments. This standard trapezoidal thread series of standards limit the size standard. Trapezoidal thread series of standards include.

--- GB/T 5796.1-2005 trapezoidal screw threads - Basic type;

--- GB/T 5796.2-2005 trapezoidal thread diameter and pitch series;

--- GB/T 5796.3-2005 trapezoidal threaded basic dimensions;

--- GB/T 5796.4-2005 trapezoidal thread tolerance;

--- GB/T 12359-2008 trapezoidal thread size limit. This standard by the National Standardization Technical Committee thread (SAC/TC108) and focal points. This standard was drafted. the machine Productivity Promotion Center, Ningbo Kowloon Fastener Manufacturing Co., Ltd. The main drafters of this standard. Li Xiaobin, Xu Yong. This standard replaces the standards previously issued as follows:

--- GB/T 12359-1990. Trapezoidal thread size limit

1 Scope

GB/T 12359-2008 is the Chinese national standard on metric trapezoidal screw threads - limits of sizes, in the field of mechanical systems and components. The /T suffix marks it as a recommended standard: it is not compulsory by itself, but it becomes binding as soon as a contract, a tender or a customer specification calls it up - which in practice is how most foreign buyers meet it. It was issued on 30 July 2008 by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China; Standardization Administration of China, and has been in force since 1 February 2009. Classification: ICS 21.040.10, CCS J04. This page is published from the official record of the standard held by the Chinese standards administration: the identification, the dates, the classification and the issuing body are taken from there. The clause text, the tables and the numeric limits are in the document itself, which is delivered complete in English translation.

This standard is based on GB/T 5796.2-2005 "trapezoidal thread diameter and pitch Series" and GB/T 5796.4-2005 "trapezoidal thread Tolerance "provides the ultimate size of the trapezoidal thread. Trapezoidal thread profile in line with GB/T 5796.1-2005 "trapezoidal thread profile" of Provisions. This standard applies to the nominal diameter 8mm ~ 300mm, the tolerance band of 7H, 8H, 9H, 7e, 8e, 8c and 9c of common trapezoidal thread.

2 Normative references

The following documents contain provisions which, through reference in this standard and become the standard terms. For dated references, subsequent Amendments (not including errata content) or revisions do not apply to this standard, however, encourage the parties to the agreement are based on research Whether the latest versions of these documents. For undated reference documents, the latest versions apply to this standard.

GB/T 5796.1-2005 trapezoidal thread - Part 1. tooth shape (

ISO 2901.1993, ISO metrictrapezoidalscrew threads-Basicprofileandmaximummaterialprofiles, MOD)

GB/T 5796.2-2005 trapezoidal thread - Part 2. The diameter of the pitch series (

ISO 2902. 1977, ISO metric trapezoidalscrewthreads-Generalplan, MOD)

GB/T 5796.4-2005 trapezoidal thread - Part 4. Tolerances (

ISO 2903.1993, ISO metrictrapezoidalscrew threads-Tolerances, MOD)

GB/T 14791 threads term ( GB/T 14791-1993, neq ISO 5408. 1983)

3 Terms and Definitions

Terms and definitions GB/T 14791 stipulated apply to this standard. Size Limit 4 female

4.1 internal thread diameter tolerance zone and its position shown in Figure 1.

4.2 internal thread size limit formula Rao D4min = D + 2 c D2min = D-0.5P D2max = D2min + TD2 D1min = D-P D1max = D1min + TD

1 Limit the size of the internal thread 4.3 7H. nominal diameter 8mm ~ 300mm within the limits of the size of the thread in Table 1; 8H. nominal diameter 8mm ~ 300mm within the limits of the size of the thread in Table 2; 9H. nominal diameter 8mm ~ 100mm internal thread size limits in Table 3.