1 Materials and main machines:
1.1 Bolts, nuts and washers shall be accompanied by a certificate of quality and shall conform to the requirements of the design and national standards.
1.2 High-strength bolt storage should be classified according to specifications, and prevent rain, moisture. In case of Bolt, nut does not match, thread damage, may not use. bolts, nuts, washers have rust, should be sampled to check the fastening shaft force, to meet the requirements of the rear can be used.
bolts, etc. shall not be contaminated by dirt, oil, keep clean, dry state. Must be in batches, with the use of ancillary, not mixed and mixed.
1.3 Main machinery: electric torque wrench and control instrument, manual torque wrench, hand wrench, wire brush, tool bag, etc.
2 Operating conditions:
2.1 Friction Surface Treatment: The friction surface uses the sand blasting, the grinding wheel polishing and so on processing, the friction coefficient should conform to the design request (one request Q235 steel to be more than 0.45, 16 MN steel is above 0.55). Friction surface wood is allowed to have residual oxide, after processing the friction surface can generate red rust after the installation of bolts (general open storage 10d or so), with sand spray treatment of the friction surface need not rust can be installed bolts. Grinding wheel grinding, grinding range is not less than 4 times times the diameter of the bolt, grinding direction and force direction perpendicular to the friction surface after grinding should have no obvious uneven. Friction surface to prevent contamination by oil or paint, such as pollution should be thoroughly cleaned.
2.2 Check the pore size of the bolt hole, burr must be removed.
2.3 The same batch number, specifications of bolts, nuts, washers, should be equipped with packing to be used.
2.4 Electric wrench and manual wrench should be calibrated.