GB/T 3106-2016Fasteners -- Bolts, screws and studs -- Nominal lengths and thread lengths (English PDF)

Foreword

This Standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This Standard replaces GB/T3106-1982, Nominal Lengths for Bolts, Screws and Studs

–and Thread Lengths for General Purpose Bolts. Compared with GB/T 3106-1982, the

main technical differences are as follows.

-- it changes the name of the standard;

-- it adds symbols and terms (Chapter 3);

-- it adds the designation of lengths and thread lengths (Chapter 4);

-- it gives limiting dimensions in accordance with product grades (Table 1); and

-- it changes "thread lengths for general purpose bolts" into "dimensions for thread

lengths".

This Standard was redrafted by reference to ISO 888.2012, Fasteners – Bolts, Screws

and Studs – Nominal Lengths and Thread Lengths (English edition).

The technical differences between this Standard and ISO 8673.2012 and their reasons

are as follows.

-- in the Normative References, it uses Chinese standards to replace the

international standards (Chapter 2), in order to meet Chinese basic standards of

fasteners.

This Standard was proposed by China Machinery Industry Federation.

This Standard shall be under the jurisdiction of the National Standardization Technical

Committee on Fasteners (SAC/TC 85).

The responsible drafting organizations of this Standard. China Productivity Center for

Machinery.

The drafting organizations of this Standard. Shanghai Jinma High Strength Fastener

Co., Ltd., Shaoxing Sunny High Strength Fasteners Co., Ltd. and Aozhan Industrial

Co., Ltd.

This Standard shall be interpreted by the Secretariat of the National Standardization

Technical Committee on Fasteners.

The previous edition replaced by this Standards is as follows.

-- GB/T 3106-1982.

Fasteners – Bolts, Screws and Studs –

Nominal Lengths and Thread Lengths

1 Scope

This Standard specifies the nominal lengths and thread lengths for bolts, screws and

studs used in product standards and other relevant documents, for example parts

drawings.

This Standard applies to bolts, screws and studs whose thread is in accordance with

GB/T 192.

2 Normative References

The following referenced documents are indispensable for the application of this

document. For dated references, only the edition dated applies to this document. For

undated references, the latest edition of the referenced document (including any

amendments) applies to this Standard.

GB/T 2 Fasteners – Ends of Parts with External Thread (GB/T 2-2016, ISO

4753.2011, MOD)

GB/T 192 General Purpose Metric Screw Threads – Basic Profile (GB/T 192-2003,

ISO 4759-1.2000)

GB/T 3103.1 Essential Oils and Aromatic Extracts – Determination of Residual

Benzene Content (GB/T 3103.1-2002, ISO 4759-1.2000, IDT)

GB/T 5276 Fasteners – Bolts, Screws, Studs and Nuts – Symbols and Description

of Dimensions (GB/T 5276-2015, ISO 225.2010, MOD)

3 Symbols

b thread length

b1 thread length of one end for double-end stud

b2 thread length of the other end for double-end stud

bm thread length of the stud metal end

d nominal diameter of the thread

l nominal length (of bolt, screw or stud)

-- lg, max = lnom – b

-- ls, min = lg, max – 5P

b) for slotted or recessed screws and similar screws (e.g. pan head, cheese head,

countersunk head specified in GB/T 5276) and studs, the tolerance for b is .

......