High-strength
Bolts are widely used in engineering projects such as bridges, steel structures, and high-pressure equipment. They are characterized by their large load-bearing capacity and the need for a significant pre-tightening force.
To ensure construction quality and safety, here are the key precautions for high-strength bolt installation:
1. Complete Tightening on the Same Day
All high-strength bolts installed on a given day should be fully tightened on the same day. Delays in tightening may lead to uneven force on the bolts or loosening, which could affect the connection's strength.
2. Bolt Insertion Direction
The direction of bolt insertion should be arranged according to the construction needs, ensuring that the bolts in each connection node are aligned uniformly. Improper installation may compromise the reliability of the structural connection.
3. Handling Over-tightened Bolts
If a high-strength bolt is over-tightened, it should be replaced immediately and must not be reused. Over-tightened bolts can lose strength, compromising the integrity of the connection.
4. Correcting Misplaced or Missing Holes
In the case of misplaced or missing holes during installation, gas cutting should not be used to open new holes. Instead, the incorrect holes should be welded, ground smooth with a grinding wheel, and then re-drilled to ensure the hole size meets requirements.
5. Use of Special Tool Bags for Storage
High-strength bolts,
Nuts, and washers should be stored in designated tool bags to prevent them from falling, especially during high-altitude work, to avoid safety hazards.
6. Do Not Substitute with Ordinary Bolts
Ordinary bolts must not be used as substitutes for high-strength bolts during installation. Ordinary bolts have lower strength and cannot meet the load-bearing requirements of high-strength connections, potentially compromising the safety of the structure.
7. Tightening Force Inspection
The tightening force of high-strength bolts must meet design specifications. During installation, specialized torque tools should be used for precise measurement to ensure the pre-tightening force for each bolt reaches the required standard.
8. Environmental Requirements for Installation
The installation of high-strength bolts should be carried out in a dry environment, free from corrosive gases, to prevent the bolts, nuts, and other metal components from rusting or being damaged, which could affect performance.
Conclusion
High-strength bolts play a crucial role in critical engineering projects such as steel structures. It is essential to strictly follow the above precautions during installation to ensure connection quality and structural safety. Proper installation and maintenance will significantly enhance the load-bearing capacity and lifespan of the structure.
