ATTEN: Manager Liu
ADD: Longhua Development Zone, Jing County, Hengshui City, Hebei Province
All steel pipes and steel plates used in truss steel trusses will be pre-treated before cutting. The steel pipe is shot blasted and rust removed in the painting workshop, and the steel plate is pretreated by the steel plate pretreatment pipeline, so that the surface roughness of the steel reaches Sa2.5 grade and then sprayed with maintenance primer, so as to ensure the stainless steel during the processing and production and the final coating quality of the product 2.2.3, lofting and blanking, according to the detailed design drawings before making, and leveling the lofting. On the platform, 1:1 physical lofting of the swing column is carried out to customize the manufacturing accuracy of the processing template and spline. All the components on the lower, lower ear plate and arc box girder of the swing column are cut by NC cutting machine to ensure the accuracy of the cutting data. Because the grid joints are welded spherical joints, the cutting quality of the rod section will directly affect the accuracy and welding quality of the components. For such joints, steel pipe intersecting line cutting machine is equipped on the steel pipe processing line to cut and cut the end of the joints. The special slotting machine for grid members is used to cut and cut the ends. The error control is that the - 1 box truss consists of two box girders supported by circular steel pipe, and the HID - 600EH intersecting line provided by Japan Maruxiu Machinery Co. Ltd. is used to cut and cut the round steel pipe. The cutting, groove and precision control of this equipment are all completed by computer control at one time. The accuracy error is not more than 1 mm2.2.4. Before assembling all swing column steel tubular joints on site, the assembly frame should be made according to the paper and specifications. After passing the supervision inspection, the assembling frame should be manufactured. The grooved steel pipes and the formed oblique and abdominal dowels are assembled according to the number and positioned by spot welding.
Because the assembly and positioning of the upper and lower chords of the web is complex, it is very important to control the four control buses of the web bar and the four control points of the corresponding spherical joints, so the positioning of the same web bar on the spherical joints should be ensured. The welding shrinkage and deformation should be considered when positioning, and measures should be taken to eliminate the deformation. The ear plate will be hoisted and assembled at the same time when assembling. After passing the inspection, the assembling of welded box truss is to put solid samples on the assembly platform for assembling, and the welding shrinkage should be pre-placed (to the upper limit of the standard tolerance). The first truss is assembled on the platform and welded for positioning. Then the truss is removed and the second truss is assembled to ensure the size of the truss. This method assembles other trusses one by one. 2.2.5 Before welding is manufactured, the welding process test evaluation and process method test are carried out, strictly in accordance with the requirements of welding specification]G]81-91, and the control of groove form, welding procedure, current, welding layer control, welding speed, etc.
Through the welding process experiment, the welding process and method suitable for the characteristics of this project are found out. After the inspection and acceptance of steel structure production, the second shot peening and rust removal will be carried out in the painting workshop, then zinc-rich paint will be sprayed, column foot ear plate and support will be treated with hot spraying zinc 3, installation construction technology 3.1, the actual construction schedule of steel structure main body installation and deployment site is BC area completed first, followed by A area, and the construction schedule will be completed immediately. Considering the joint construction period and economic rationality, the main steel structure construction is divided into three blocks (see figure 3).