Hex socket head cap screw(GOSHO(Gosei(Coarse Steel Unplated 24 X 55 Pitch 3.0

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This is a bolt with a cylindrical head featuring a hexagonal socket.
Tightening is performed using a hex key (Allen wrench). Although classified as a bolt, it is in most cases used without a nut.
It is also referred to as a cap screw or socket screw.
Spanners and wrenches with jaws for tightening hex bolts require clearance space around the work area, whereas a hex key requires no such space.
For this reason, the use of hex socket head cap screws allows work in confined spaces and enables more compact machine designs.
Due to their appearance, they are also increasingly being used for decorative purposes.

• Hex socket head cap screw Gosei Gosei Coarse pitch
• Nominal diameter M24
• Length under head (ℓ) 55.0
• Pitch 3.0
• Thread section (b) Reference 60
• Head diameter (dk) Max 36.39 Min 35.61
• Neck diameter (da) Max 26.4
• Body diameter (ds) Max 24 Min 23.67
• Head height (k) Max 24 Min 23.48
• Neck fillet (r) Min 0.8
• Hex socket width across flats (s) Nominal 19 Max 19.275 Min 19.065
• Hex socket depth (t) Min 12
• Head chamfer (v) Max 2.4
• Full thread range 85
• Strength class 12.9(M2~M20) 10.9(M22~M24) 10.9(Electro zinc plating)