The difference between precision cold drawn tubes

- Mar 01, 2020-

Fine cold-drawn pipe (fine-drawn pipe) is a kind of high-precision steel pipe data that uses cold-drawn pipe seamless pipe as the original material for public service control and appearance light processing. The fine cold drawn pipe has the characteristics of high precision, high finish, good cleanliness of the inner wall, high pressure without leakage of the steel pipe, no deformation in cold bending, flaring, no cracking in flattening, and can be used for various messy deformation and mechanical processing.

 The chemical composition of fine cold-drawn tubes is carbon C, silicon Si, manganese Mn, sulfur S, phosphorus P, chromium Cr. Primary uses: cars, motorcycles, refrigeration equipment, hydraulic parts, pneumatic cylinders, and other precision steel pipes, Customers with high requirements for smoothness, cleanliness and mechanical properties. Primary use: For cars, motorcycles, refrigeration equipment, hydraulic parts, bearings, pneumatic cylinders, and other customers who have high requirements for the accuracy, smoothness, cleanliness, and mechanical properties of steel pipes.

The difference of fine cold drawn pipe is modified. The main feature of general seamless steel pipe is no weld seam, which can accept large pressure. The product can be very rough cast or cold drawn. The precision cold drawn tube is mainly with strict service and roughness on the inner hole and outer wall scales, and the precision is extremely high. Cold brittle alloy steel with body-centered cubic lattice will change from resistant cracking to brittle cracking when the experimental temperature decreases. Many industrial cold-rolled fine bright steel pipes will become brittle at room temperature to subzero temperature scale, which is called cold brittleness.

The cold brittleness (or tendency to low temperature embrittlement) of cold rolled fine bright steel pipes is indicated by the resistance-brittleness transition temperature Tc. The Tc of high-purity iron (0.01% C) is at 100C. Below this temperature, it is completely in a brittle state. Most of the alloy elements in the cold-rolled fine-bright steel pipe increase the resistance-brittleness transition temperature of the cold-rolled fine-bright steel pipe, and the tendency of cold-brittleness is added. When resistance to cracking is above room temperature, the fracture of cold-rolled fine bright steel pipe is a dimple fracture, and when it is brittlely cracked at low temperature, it is a cleavage fracture.