2H Heavy Hex Nuts Supplier introduces the installation and construction requirements of steel structure fasteners:
1. When ordinary bolts are used as connecting bolts when the design has requirements or there are doubts about their quality, the small tensile load of the bolts should be re-examined, and 8 bolts of each specification should be randomly checked;
2. The torsional shear type high-strength bolt connection pair should be re-examined for pre-tension and an inspection report should be issued. 8 sets of connection pairs should be selected from each batch for re-inspection. The average and standard deviation of pre-tension should meet the requirements of the following table:
3. The high-strength bolt connection pair should be stored according to the batch number and specification on the packing box. It is strictly forbidden to open the box before use to prevent contamination with stolen goods;
4. The torque coefficient of the high-strength large hexagon head bolt connection pair should be re-inspected and an inspection report should be issued. 8 sets of connection pairs should be selected from each batch for re-inspection. After re-inspection, the average torque coefficient of each group of 8 sets of connection pairs should be calculated. is 0.110 to 0.150, and the standard deviation is less than or equal to 0.010;
5. The high-strength bolts are collected according to the quantity needed on the day. The warehouse should register the user, the specification, the quantity, and the part used. The remaining bolts should be properly kept and should not be thrown or placed indiscriminately;
6. For the bolted ball joint steel grid structure with a building structure grade of first class and a span of 40m and above, the surface hardness test shall be carried out for the connecting high-strength bolts, and 8 pieces shall be randomly checked according to the specifications. The hardness of high-strength bolts of grade 8.8 should be HRC21-29; the hardness of high-strength bolts of grade 10.9 should be HRC32-36, and there should be no cracks or damage.
7. The high-strength bolt connection pair should be supplied according to the packing box, and the batch number, specification, quantity, and production date should be marked on the packing box. The appearance surface of bolts, nuts, and washers should be oiled to protect, there should be no rust and contamination with dirt, and the threads should not be damaged;
8. In the process of transportation and storage, the high-strength bolted connection pair must be lightly loaded and unloaded, and the threads must not be damaged; the main construction equipment and tools must be prepared before installation and construction; all parts and components are prefabricated and assembled and inspected. The site and discharge material site are ready and have construction conditions.