Q345C seamless steel pipe has a hollow section and is widely used as a pipeline for transporting fluids, such as pipelines for transporting oil, natural gas, gas, water and certain solid materials. There are two main uses of Q345C seamless steel pipes: pipes for machining and pipes for fluid transportation. Some other special pipes, etc.
Carbon Steel/ Alloy Steel
10#(St37.4,St35,St37,E235),20#(St45,St44,E255),45#(Ck45),16Mn(St52) and other special
Cold rolled & Cold drawn
Widely used in automobiles, motorcycles, gas springs, hydraulic machinery,
construction machinery and refrigeration industry.
main differenceedit broadcastDifference between Q345A and Q345B and Q345C
Mechanical performance index (%):
Grade Wall Thickness mm Elongation δ5≥(%) Yield Strength δs(MPa≥) Test Temperature ℃
Q345A ≤16 21 345 Not required
Q345B ≤16 21 345 20
Q345C 16-35 22 ≥325 0
Grade C Si Mn PSV Nb Al Ti
Q345A ≤0.20 ≤0.55 ≤1.70 ≤0.045 ≤0.045 0.02-0.15 0.015-0.060 0.02-0.20
Q345B ≤0.20 ≤0.55 ≤1.70 ≤0.040 ≤0.040 0.02-0.15 0.015-0.060 0.02-0.20
Q345C ≤0.20 ≤0.55 ≤1.70 ≤0.035 ≤0.035 0.02-0.15 0.015-0.060 ≥0.015 0.02-0.20
The main difference is the carbon and manganese content:
Carbon C: 0.14～0.22; Manganese Mn: 0.30～0.65;
Carbon C: 0.12～0.20; Manganese Mn: 0.30～0.70;
It is used for carburized or cyanided parts that do not require high core strength, such as tie rods, connecting rods, hooks, bolts, shafts and welding parts, etc.
There should also be a limit to the temperature!
Especially the Q345E. dozens of degrees below zero.
In addition, compared with the old standard, the most obvious requirement of the new standard is the adjustment of the Mn content in the steel, from the original 1.0-1.60 to ≤1.70, and the minimum limit of ≥1.0 is cancelled.