In the grid assembly process, bolt tightening is the most basic and also the most important work, which is related to the quality of the grid engineering. Today, the editor of Jiangsu Huahai Steel Structure will introduce three ways to tighten the grid bolts.

1. Torque-angle control method

Definition: First screw the anchor bolts to a not large torque, and then start to tighten a required corner control measure.

Advantages: The accuracy of the radial pre-tightening force of the anchor bolts of the grid structure is high (±15%), and it can be subjected to a large radial pre-tightening force, and the standard value can be concentrated around the average value.

2. Scope control method

Definition: A way to terminate the tightening after the anchor bolts of the grid structure are tightened to a certain extent.

Advantages: The tightening accuracy is very high, and the pre-tightening force deviation can be manipulated within ±8%; but the key to its accuracy lies in the tensile strength of the anchor bolt itself.

3. Torque control method

Definition: When the tightening torque exceeds a certain set operating torque, the tightening control measures are immediately terminated.

Advantages: The automatic control system is simple and immediate, and it is convenient to use torque or high-precision torque wrench to check the quality of tightening.