The company has allocated special environmental protection facilities for all A709 grade 50 structural steel sheet pollution sources, strengthened the recycling of waste resources and improved the efficiency of resource utilization. At present, the recovery and utilization rate of solid wastes such as iron slag, steel slag, iron bearing dust, A709 grade 50 structural steel sheet steel mill scale, environmental protection dust has reached 100%.
A709 grade 50 structural steel sheet, A588GrB material is a high-strength low-alloy structural steel in shapes of profiles, plates and bars. Through the alloying of Cu, P, Cr, Ni, a protective layer is formed on the surface of the metal substrate, so that A588GrB steel has a high resistance to atmospheric corrosion. A588GrB high-strength low-alloy steel is widely used in various weather-resistant building structural parts (especially for industrial atmospheric environments), bridge auxiliary structural parts.
15CrMo alloy steel plate is pearlite structure heat-resistant steel, which has high heat strength (δb≥440MPa) and oxidation resistance at high temperature, and has certain resistance to hydrogen corrosion. Due to the high content of Cr, C and other alloying elements in steel, the hardening tendency of steel A709 grade 50 structural steel sheet is obvious and the weldability is poor. 15crmo alloy steel plate is mainly used in petroleum, petrochemical, high-pressure boilers, etc.
S355J2 steel plate rolling process is controlled rolling process. In the rolling process, the ingot rolling temperature is 1000-1050℃; in the first stage, the low-speed and large reduction rolling process is adopted, the high-temperature stage is 950-1000℃, the A709 grade 50 structural steel sheet rolling speed is 1.6-2.0m/s, the single reduction rate is 15-20%, and the cumulative reduction rate is 40-45%, so as to ensure sufficient deformation of ingot. In the first stage, the start rolling temperature is 910-930℃, and the finish rolling temperature is ≤ 870℃.As a basic building material, steel plates are currently widely used in automobiles, shipbuilding, chemical industry, aerospace and other fields. Reasonable selection of flaw detection methods to ensure the quality of A709 grade 50 structural steel sheet steel plates is of great significance to safe production. Common defects of steel plates are folding, inclusion, shrinkage, air bubbles, delamination and cracks. These problems can be discovered in time through flaw detection.
The chemical composition difference between A709 grade 50 structural steel sheet, Q235B and 20# steel is as follows: The chemical composition of 20# steel: C: 0.17-0.23%, Si: 0.17-0.37%, Mn: 0.35-0.65%, Cr: ≤ 0.25%, Ni: ≤ 0.30%, Cu: ≤ 0.25%. Chemical composition of Q235B steel: C: ≤ 0.20%, Si: ≤ 0.35%, Mn: ≤ 1.40%, P: ≤ 0.045%, S: ≤ 0.045%. The difference of mechanical properties between A709 grade 50 structural steel sheet, Q235B and 20# steel is as follows: The mechanical properties of 20# steel: tensile strength 410 MPa; yield strength 245 MPa; elongation after fracture: 25; reduction of area: 55; no impact. Q235B steel mechanical properties: tensile strength 370-500 Mpa; yield strength: ≥ 235 Mpa; elongation after fracture: 25; impact absorption energy: 27J.
The after-sales service department will pay return visit to each customer by call or email, report problems found during the return visit in time, and discuss with the production and quality inspection center to propose effective solutions and follow up in a timely manner, so as to ensure the benefits each customer are fully guaranteed, and to provide customers with more value-added services.
