Control points for acceptance of raw materials and finished products on-site

① Steel: should be based on the design requirements to specify the choice of steel grade, reference standard number, chemical composition, and physical properties of the index. Raw material suppliers should provide a complete quality assurance certificate and material test reports. The varieties, specifications, and performance of steel and steel castings should be in line with the current national product standards and design requirements, and the quality of imported steel should be in line with the requirements of design and contractual standards. Supervision shall require the steel structure contractor to submit quality certification documents, Chinese marks, and inspection reports to the supervisor for review, and the supervising engineer shall check all of them.

② Welding materials: the varieties, specifications and performance of welding materials shall meet the current national product standards and design requirements. Supervision shall require the steel structure contractor to submit quality qualification documents, Chinese signs, and inspection reports to the supervisor for examination, and the supervising engineer shall check all of them. Sampling and re-inspection of welding materials used for important steel structures. The supervising engineer shall check the re-inspection report.

③ Connecting fasteners standard parts: the fasteners commonly used in steel structure projects are high-strength bolts (divided into large hexagonal type and twisted shear type), common bolts, anchor bolts, anchor bolts, and other fastening standard parts, and their varieties, specifications, and performance should be in line with the current national product standards and design requirements. Supervision shall require the steel structure contractor to submit product quality qualification documents, Chinese marks, and inspection reports to the supervisor for examination, and the supervising engineer shall check all of them.

④ Welding ball: Supervision shall require the contractor to provide the quality qualification documents of raw materials used for the welding ball, Chinese marking and inspection report, non-destructive inspection report of the weld seam of the welding ball, etc. The contractor shall check the quality of raw materials used for welding the ball with a caliper and metal thickness gauge. Use calipers and metal thickness gauge to randomly check the welding ball diameter, roundness, wall thickness reduction, and other dimensions.

bolt ball

⑤ Bolt ball: Supervision shall require the contractor to provide the raw materials used in welding ball quality certification documents, Chinese signs, and inspection. Check the surface quality of the bolt ball with 10 times magnifying glass. Random check bolt ball thread size, diameter, roundness, adjacent two bolt hole centerline angle, and other dimensions.

⑥ Metal Pressure Plate: Metal pressure plate, pressure metal flooding plate, corner wrapping plate, and spare parts and raw materials used thereof, their varieties, specifications, performance, etc. should be in line with the current national product standards and design requirements. Supervision should require the contractor to provide product quality certification documents, Chinese signs, and inspection reports. Pressure metal plate specification size deviation, surface, and coating quality for random inspection (available 10 times magnifying glass).

⑦Coating materials: Supervision shall require the contractor to provide product quality qualification documents, Chinese signs, and inspection reports. The varieties and technical performance of materials for steel structure anticorrosion coating and fireproof coating shall meet the design requirements, and the fireproof coating shall be tested by a qualified inspection organization to meet the provisions of current national standards and confirmed by the local fire control department.

⑧ The control of raw materials and finished products of the steel structure project is the key to ensuring the quality of the project and one of the control points, all the raw materials and finished products of quality specifications, performance, etc. should be in line with the national product standards and design requirements and should be checked in full to locate the quality of the product qualification documents and inspection reports, etc. as the main control items.

⑨ on the welding materials used in the project, there should be a complete quality certificate, and baked before use by the requirements of the manual. Supervision engineers should check the validity of the quality certificate and welding material baking records. Check the welder's certificate of competency, including whether the examination pass items can cover the actual welding content, and whether the certificate of competency is valid. Check whether the items of the welding process evaluation report cover so joints of the project. Ultrasonic flaw detection must be carried out for primary and secondary welds. For welds that require preheating before welding or post-welding heat treatment, the temperature between the weld channels during the entire welding process shall not be lower than the preheating temperature, and the width of the preheating on both sides of the weld shall not be less than 1.5 times the thickness of the weldment. And should not be less than 100mm.

⑩ should be butt welds of the residual height, biting edge, surface weld tumor, shrinkage; fillet welds of the weld corner size, biting surface quality of not less than 20% of the inspection, and make a good inspection record. For bolt welding supervision should check its welding process evaluation report, and porcelain ring baking records. After the bolts were welded supervision together with the construction unit quality inspection personnel to draw 10% of the same kind of components (not less than 10 pieces), 1% of the number of bolts per piece of inspection, and bending test. After bending 30 ° angle with an angle ruler and visual observation, the pegs should be fused with the weldments around the bend.

The above are the control points of the acceptance work of raw materials or finished products into the field, if you have any questions related to the acceptance of steel structure, welcome to discuss them with us.