GB/T 1231-2024 High strength bolts with large hexagon head assemblies for steel structures
1 Scope
This document specifies the type and dimension, technical requirements, test methods, inspection rules, designation, marking, labeling, packaging and quality inspection reports of high strength bolts with large hexagon head assemblies for steel structures (hereinafter referred to as "bolt assemblies").
This document is applicable to friction-type high strength bolt assemblies for railway and highway bridges, tower and mast structures, boiler steel structures, industrial and civil buildings, hoisting machinery and other steel structures.
2 Normative References
The following documents contain provisions which, through reference in this text, constitute provisions 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 2 Fasteners - Ends of parts with external thread
GB/T 90.1 Fasteners - Acceptance inspection
GB/T 196 General purpose metric screw threads - Basic dimensions
GB/T 197 General purpose metric screw threads - Tolerances
GB/T 228.1 Metallic materials - Tensile testing - Part 1: Method of test at room temperature
GB/T 229 Metallic materials - Charpy pendulum impact test method
GB/T 230.1 Metallic materials - Rockwell hardness test - Part 1: Test method
GB/T 699 Quality carbon structure steels
GB/T 1237 Designation system for fasteners
GB/T 3077 Alloy structure steels
GB/T 3098.1 Mechanical properties of fasteners - Bolts, screws and studs
GB/T 3098.2 Mechanical properties of fasteners - Nuts
GB/T 3103.1 Tolerances for fasteners - Bolts, screws, studs and nuts
GB/T 3103.3 Tolerances for fasteners - Plain washers
GB/T 4340.1 Metallic materials - Vickers hardness test - Part 1: Test method
GB/T 5276 Fasteners - Bolts, screws, studs and nuts - Symbols and designations of dimensions
GB/T 5277 Fasteners - Clearance holes for bolts and screws
GB/T 5779.1 Surface discontinuities of fasteners on bolts, screws and studs for general requirements
GB/T 5779.2 Fasteners - Surface discontinuities - Nuts
GB/T 6478 Steels for cold heading and cold extruding
JJG 707 Verification regulation of torque wrenches
3 Terms and definitions
No terms and definitions are listed in this document.
4 Types
The bolt assemblies include a bolt, a nut, a washer A and a washer B, the type of which shall be in accordance with Figure 1. The internally and externally chamfered washer A is used under the bolt head, and the externally chamfered washer B is used under the nut, which are distinguished by different colors.
Key:
1——bolt;
2——washer A;
3——washer B;
4——nut.
Figure 1 Type diagram for bolt assemblies
5 Dimensions
5.1 Bolts
For bolts, the type shall be as shown in Figure 2, the dimensions and theoretical mass shall be as specified in Table 1 to Table 3 and Table 3 respectively, and the symbols and descriptions of dimensions shall meet the requirements of GB/T 5276. The symbols and descriptions of dimensions at thread ends shall meet the requirements of GB/T 2.
Foreword i
1 Scope
2 Normative References
3 Terms and definitions
4 Types
5 Dimensions
6 Technical requirements
7 Test methods
8 Inspection rules
9 Marking, designation, labeling, packaging and quality inspection report
Annex A (Normative) Technical requirements of 35VB materials
