Views:3 Author:Site Editor Publish Time: 2018-03-09 Origin:Site
1. Before the combination of the door frame, the size and assembly number of all components shall be checked, and the combination surface of each joint web shall be cleaned, and local deformation shall be processed to ensure the combination quality of the door frame.
2. The upper and lower beam, the end beam and the main beam of the section should be combined as a whole as far as possible on the ground combination platform, so as to reduce the high-altitude operation, and the method of drawing the wire line should be measured to be not straightness, and should not be greater than or minus 2.0mm.
3. When measuring the arch or the horizontal of the main beam with the pull steel wire, it is necessary to correct the influence of the self-gravity deflection of the steel wire, and the diameter, tension force and distance of the steel wire line should comply with the relevant regulations.
4. If the connection of bolts or high-strength bolts is adopted, the construction shall be complied with.
5. The door frame hoisting shall be fixed and adjusted by using the cable and tensioner. Causes the door leg to be in any direction perpendicular to no more than 5.0mm. The span of the gate leg is not greater than or minus 5.0mm, the relative difference of the diagonal is not greater than 5.0mm, and the relative difference of the top elevation is not greater than 3.0mm.
6. When the legs meet the requirements, they can be hoisted onto the platform or the main beam, and based on the track level, the cutting platform shall be connected with the gate leg to make the platform or the main beam level. And check:
1) the deviation between the main beam center and the trolley is not greater than 3.0mm;
2) the center deviation of the portal frame is not greater than 5.0mm;
3) the relative difference of the upper structure diagonal is not greater than 5.0mm.
7. When the upper structure or the main beam and the door leg are connected by welding, it should pay attention to the high altitude, weather, wind direction and wind force and take corresponding measures.
8. The oxide of the weld groove should be cleaned up, and there is too much clearance to allow the welding of long meat, and no rebar or other materials are allowed. The front slope of the weld shall be heated at a temperature of 100mm, and a wind shield should be installed around it to slow down the cooling rate of the weld and improve the metallurgical structure.
9. Four shall be joint and welding, welding, multi-level multi-channel welds should be adopted to reduce stress and shrinkage deformation after welding inspection on weld, should comply with the relevant regulations, if no requirement, lack of penetration can be reference to joint should not be greater than the parent metal 15%, maximum of not more than 3.0 mm.