High strength large hexagonal bolts for steel structures

High strength large hexagonal bolts for steel structures

The "high-strength large hexagonal head bolt connection pair for steel structures" belongs to the connecting piece used in the "friction type high-strength bolt connection of steel structures".

1: Connecting sub materials

1: High strength bolt performance level: 10.9s

≤ M24 material 20MnTiB material standard GB/T 3077 ML20MnTiB material standard GB/T 6478

Material ≤ M30 35VB

2: Nut performance level 10h

Material 45 × Material standard GB/T 699

3: Washer HRC 35-45

Material 45 × Material standard GB/T 699

2: Connecting pair torque coefficient

High strength large hexagonal bolt connection pairs are supplied according to the guaranteed torque coefficient. The average torque coefficient of the same batch of connecting pairs is 0.110-0.150. The standard deviation of the torque coefficient should be less than 0.01%. The same connecting pair includes one bolt, two washers, and one nut, which should be manufactured in the same batch.

The torque coefficient guarantee period is 6 months from the date of delivery.

3: The basic dimensions of bolt and nut threads should comply with the provisions of GB/T 169 for coarse thread ordinary threads, and the tolerance zone of bolt threads should be 6G in GB/T 197. The tolerance zone for nuts is 6h according to GB/T 197

Torsional shear type high-strength bolts for steel structures

1: The material requirements for torsion shear bolts are the same as those for large hexagonal bolts, which are 20MnTiB and 35VB respectively

2: Torsional shear type bolts are supplied according to the tightening axial force, and the specific requirements are as follows

3: The thread size tolerance requirements for torsion shear type bolts and nuts are the same as those for large hexagonal bolts and nuts. Each set of connecting pairs consists of 1 bolt, 1 nut, and 1 washer.