Steel structure connections are very important!
# English Translation As a steel structure company, today we would like to talk about **fastening standard components for steel structure connections**. The fastening standard components used for steel structure connections include high-strength large hexagon head bolt sets, torsion-shear type high-strength bolt sets, high-strength bolts for steel space grids, common bolts, rivets, self-tapping screws, pull rivets, shooting nails, anchors (mechanical type and chemical type), anchor bolts, as well as standard accessories such as nuts and washers. Their types, specifications, properties, etc. shall comply with current national product standards and design requirements. High-strength large hexagon head bolt sets and torsion-shear type high-strength bolt sets shall be delivered with their respective test reports of torque coefficient and clamping axial force (pre-tension) in each box when leaving the factory. High-strength large hexagon head bolt sets shall be re-inspected for torque coefficient in accordance with the current Chinese standard **Code for Acceptance of Construction Quality of Steel Structure Engineering GB 50205**, and the test results shall meet the specifications. Bolts for re-inspection shall be randomly selected from the batch of bolts to be installed at the construction site, and **8 sets** of bolt sets per specification shall be taken from each batch for re-inspection. Torsion-shear type high-strength bolt sets shall be re-inspected for pre-tension in accordance with the current national standard **Code for Acceptance of Construction Quality of Steel Structure Engineering GB 50205**, and the test results shall meet the specifications. Bolts for re-inspection shall be randomly selected from the batch of bolts to be installed at the construction site, and **8 sets** of bolt sets per specification shall be taken from each batch for re-inspection. For steel grid structures with bolt-ball joints, the connecting high-strength bolts shall be subjected to tensile load or surface hardness tests. For **Grade 8.8 high-strength bolts**, the surface hardness shall be **HRC 21–29**; for **Grade 10.9 high-strength bolts**, the surface hardness shall be **HRC 32–36**, and no cracks or damages are allowed. Inspection quantity: bolts of the same specification shall be taken as one batch per 600 pieces; less than 600 pieces shall still be counted as one batch, and **3 pieces** per batch shall be randomly selected as one group for sampling inspection. For bolts for which the design requires actual load tests, the tensile strength shall meet the design requirements. If there is no design requirement, it shall comply with the current national standard **Mechanical Properties of Fasteners — Bolts, Screws and Studs GB 3098.1** or other current national product standards. Bolts for re-inspection shall be randomly selected from the batch of bolts to be installed at the construction site, and **8 sets** of bolt sets per specification shall be taken from each batch for re-inspection. If you want to know more about steel structure engineering, please feel free to contact us at any time.