1、 Quality control of steel structure processing materials

 Steel structure processing material control is a key point of quality control. The quality of material directly affects the quality of steel structure. Therefore, the material and specification of steel plate and section steel should be strictly checked and calculated in the design of steel structure.Steel, welding materials and paint must have the product quality certificate issued by the manufacturer, and meet the relevant design requirements and standard requirements.The key parts and steel plates with special requirements shall be sampled for re inspection, and the materials that pass the sampling re inspection can be used for blanking.When the steel surface has rust, pitting or scratch and other defects, the depth of which exceeds the allowable negative deviation of steel thickness by 1 / 2 is strictly prohibited.Welding materials should be selected strictly according to the welding process, and must be matched with steel. The purity of cutting gas should be ensured. 

 2、 Control of material cutting process for steel structure

 After the steel structure processing materials enter the workshop, it is necessary to check whether the specifications and materials meet the technical requirements of the design drawings.Before cutting, the rust, oil stain and oxide film on the surface of the cutting area shall be removed, and the cutting shall be carried out in strict accordance with the marking.The cutting surface shall be free of cracks, slag inclusion, delamination and lack of edge greater than 1.0 mm. The edge of molten tumor and spatter shall be removed in time, otherwise, it is forbidden to transfer to the next process.The ordering unit, part number, processing method, etc. shall be indicated after the plate marking. The flange plate and web plate of important components such as steel column and crane beam shall be cut by semi-automatic or automatic gas cutting machine. If the web plate and flange plate need to be butted due to insufficient length of raw materials, they shall be butted first and then cut, and 30-50mm waste materials shall be reserved in the length direction.The butt welding seams of flange plate and web plate shall not be set at the same section, and shall be staggered by more than 200 mm, and shall also be staggered with stiffening plate by more than 200 mm.