The material of 20# seamless pipe is generally 20 seamless pipe. The material of 20# steel pipe is: high-quality carbon structural steel grade: 20 steel standard: GB/T 699-1988, 20# seamless steel pipe characteristics and scope of application: strength It is slightly higher than 15# steel, rarely quenched, and has no temper brittleness. Cold deformation plasticity is high, generally used for bending, calendering, flange bending and hammer arch processing, arc welding and contact welding have good welding performance, small thickness during gas welding, parts with strict shape requirements or complex shapes are prone to cracks. The cold-drawing or normalizing state of the cutting process is better than the annealing state, and it is generally used for manufacturing with less stress and high toughness requirements.

Chemical composition of 20# seamless pipe: carbon C: 0.17～0.24, Si: 0.17～0.37, Mn: 0.35～0.65, S: ≤0.035, P: ≤0.035, Cr: ≤0.25, Ni: ≤0.25, Cu: ≤0.25. 20# Seamless steel pipe mechanical properties: tensile strength σb (MPa): ≥410 (42) yield strength σs (MPa): ≥245 (25) elongation δ5 (%): ≥25 section shrinkage ψ (% ): ≥5, hardness: unheated, ≤156HB, sample size: sample size 25mm 20# seamless steel tube heat treatment specification and metallographic structure: heat treatment specification: normalizing, 910℃, air cooling. metallographic structure: ferrite +Pearlite.

20# Seamless tube delivery status: delivered in a state of no heat treatment or heat treatment (annealing, normalizing or high temperature tempering). Requirements for delivery in heat-treated state shall be indicated in the contract, and those not specified shall be delivered without heat treatment.