BS 2470:1973

Cooperating organizations
Foreword
Specification
1. General
1.1 Scope
2. Hexagon socket screws
2.1 Material
2.2 Finish
2.3 Dimensions
2.4 Head diameter
2.5 Length of socket screws
2.6 Tolerance on length
2.7 Ends of socket screws
2.8 Screw threads
2.9 Radius under head
2.10 Length of thread
2.11 Concentricity and straightness
2.12 Dimensions of hexagon sockets
3. Hexagon wrench keys and bits
3.1 Material
3.2 Finish
3.3 Dimensions
3.4 Ends of keys
3.5 Torque test
3.6 Application
Appendices
A. Mechanical properties of finished alloy steel
    hexagon socket screws and wrench keys
B. Dimensioning of countersunk head screws
C. Terminal length increments for socket screws
Tables
1. Option 1 for thread length and grip lengths of cap
    screws having UNC, UNF, BSW, BSF and BA threads
2A. Dimensions of hexagon socket head cap screws, ISO
    inch (Unified) threads
2B. Dimensions of hexagon socket head cap screws, BSW
    and BSF threads
2C. Dimensions of hexagon socket head cap screws, BA
    threads
3. Dimensions of hexagon socket countersunk head screws
    with ISO inch (Unified) threads
4. Dimensions of hexagon socket button head screws
    with ISO inch (Unified) threads
5. Hexagon socket head shoulder screws (stripper bolts)
    with ISO inch (Unified) and BSW/BSF threads
6A. Dimensions of hexagon socket set screws with ISO
    inch (Unified) threads
6B. Dimensions of hexagon socket screws with BSW and BSF
    threads
6C. Dimensions of hexagon socket set screws with BA
    threads
6D. Dimensions of hexagon socket set screws with G(BSPF)
    threads
7. Dimensions of hexagon sockets
8. Dimensions of hexagon wrench keys
9. Applicability of hexagon wrench keys to various
    socket screw types and sizes
Figures
1. Alternative types of cup point and socket permissible
    with hexagon socket set screws with ISO inch
    (Unified), BA, BSW and BSF and G(BSPF) threads