1) according to the provisions of the "steel structure welding regulations", put forward the welding procedure qualification scheme;
2) The reference point shall be selected based on the center line of the column base of the standard column, and the compensation line with the distance of 1000mm shall be led out in two axial directions respectively, and its intersection point shall be used as the measurement reference point of the standard column, so the reference point shall be protected during construction to prevent damage;
3) Elevation putright: according to the leveling points provided by the owner, close measurement is carried out with a level, and the reference points of each construction section are laid out on the concrete of the nearby elevator shaft and protected, and the putright points are used as the engineering elevation basis for construction, and are gradually transmitted upwards;
4) The installation of anchor bolts is generally carried out by setting a fixed frame, which should be self-contained to avoid connection with formwork and scaffolding, so as to avoid vibration and impact during construction, causing bolt displacement and affecting accuracy;
5) For steel structure hoisting, as the steel column is a single component, symmetrical installation and symmetrical fixing techniques should be adopted during hoisting, which is beneficial to eliminate the accumulation of installation errors and welding deformation of nodes and minimize the errors. When the steel column is hoisted, measurement, calibration, initial screwing, final screwing and welding of high-strength bolts are carried out, and then the next steel column is hoisted;
6) One-point hoisting of the steel column, using the bolt hole of the ear plate of the column top installation process, setting an auxiliary steel plate to form a hoisting point, and the hook passes through the center of gravity of the steel column, which is convenient for hoisting, alignment and correction of the steel column;
7) The overall welding sequence extends from the center of the plane to both sides, and adopts structural symmetry, nodal symmetry and overall symmetry welding; Double symmetry welding method is adopted for the same node;
8) During the welding process, the relevant welding parameters should be controlled strictly according to the welding process requirements, and the deformation of components should be checked at any time; If there is any problem, the welding process should be adjusted in time. In order to prevent welding shrinkage of steel columns, when adjusting the elevation of each steel column, the welding shrinkage value of 5- 10㎜ should be reserved.
During CO2 gas shielded welding, wind should be kept around the weld, and welding is not allowed in rainy days.
10) In the on-site construction of multi-storey and high-rise steel structure engineering, joint treatment is directly related to structural safety and engineering quality, which must be handled reasonably and strictly controlled. Welded joints must be tested in strict accordance with the nondestructive testing scheme.
More inquiries about the winning performance, integrity information and qualification conditions of construction enterprises, one-click instant query results, download Jianjiantong app.
For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd