Processing of steel structure engineering connectors and treatment of friction surfaces
1. The bolt holes of the connecting parts shall be processed according to the relevant regulations. The accuracy of the bolt holes, the surface roughness of the hole wall, the allowable deviation of the hole diameter and the hole distance, etc. shall comply with the current national standard "Code for Construction Quality Acceptance of Steel Structure Engineering" GB50205. Regulation.
2. When the bolt hole distance exceeds the specified allowable deviation, welding electrodes that match the base metal can be used for repair welding, and the holes should be re-made after passing the non-destructive test. The number of pre-drilled holes after repair welding in each group of holes must not exceed 20% of the number of bolts in this group.
3. The gap between the friction surfaces of high-strength bolts due to plate thickness tolerances, manufacturing deviations, or installation deviations should be handled according to regulations.
4. The friction surface of the high-strength bolt connection can be treated according to the requirements of the design anti-slip coefficient, and the anti-slip coefficient should meet the design requirements. When grinding with a manual grinding wheel, the grinding direction should be perpendicular to the force direction, and the grinding range should not be less than 4 times the bolt hole diameter.
5. The friction surface of high-strength bolt connection after surface treatment shall meet the following requirements:
(1) The connection friction surface should be kept dry and clean, and there should be no flash, burr, welding spatter, welding scar, iron oxide scale, dirt, etc.;
(2) Protective measures shall be taken for the treated friction surface, and no marking shall be made on the friction surface;
(3) When the friction surface adopts the rust treatment method, the floating rust on the friction surface should be removed with a fine steel wire brush perpendicular to the force direction of the component before installation.