Precision seamless steel pipes(asme sa 106 gr b) are widely used. Widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipes, automobile transmission shafts, bicycle frames, and steel scaffolding used in building construction. Steel pipes are used to make ring parts, which can improve material utilization, simplify manufacturing procedures, and save materials and processing. Working hours.
General-purpose precision precision seamless steel pipes are rolled from ordinary carbon structural steel, low-alloy structural steel or alloy structural steel, and have the largest output. They are mainly used as pipelines or structural parts for conveying fluids.
According to different purposes, it can be supplied in three categories:
a. Supply according to chemical composition and mechanical properties;
b. According to mechanical performance;
c. According to the water pressure test supply. For steel pipes supplied in accordance with category a and b, if they are used to withstand liquid pressure, they shall also be subjected to a hydraulic test.
The chemical composition of steel is one of the most important factors affecting the performance of precision seamless steel pipes, and it is also the main basis for formulating pipe rolling process parameters and steel pipe heat treatment process parameters.
a. Alloying elements: intentionally added, according to use
b. Residual elements: brought in by steelmaking, properly controlled
c. Harmful elements: strictly control (As, Sn, Sb, Bi, Pb), gas (N, H, O)
Out-of-furnace refining or electroslag remelting: improve the uniformity of the chemical composition of the steel and the purity of the steel, reduce the non-metallic inclusions in the tube billet and improve its distribution shape.