The difference between large hexagonal high-strength bolts and torsion shear high-strength bolts
January 23, 2025
1. Appearance Differences
• Large Hexagon Head High-Strength Bolts: The head is hexagonal.
• Torsional Shear Type High-Strength Bolts: The head is semi-circular, and the tail end has a plum blossom head.
2. Installation Method
• Large Hexagon Head High-Strength Bolts: Installed using a torque wrench.
• Torsional Shear Type High-Strength Bolts: The tail end’s plum blossom head is used to control installation, utilizing the reaction force of the torque to tighten the bolt until the straight-toothed part of the tail end breaks.
3. Matching Components
• Large Hexagon Head High-Strength Bolts: Each set includes a bolt, a nut, and two
Flat Washers.
• Torsional Shear Type High-Strength Bolts: Each set includes a bolt, a nut, and one flat washer.
4. Torque Control
• Large Hexagon Head High-Strength Bolts: Torque is controlled by the construction tool.
• Torsional Shear Type High-Strength Bolts: These are self-indicating bolts; the tightening torque is determined by the diameter of the cut between the screw rod and the plum blossom head, controlled by the torsion breaking force, requiring a special electric wrench for installation.
Conclusion
Although both types of bolts have similar mechanical performance, torsional shear type high-strength bolts are preferred in high-rise steel structure projects due to their ease of installation, straightforward inspection, and reliable performance.
