Abstract
Effects of heat treatment process of quenching and tempering under different temperature conditions on mechanical properties of X70 grade pipeline steel bends were studied. Brinell hardness, yield strength, tensile strength, elongation and impact absorbing energy of the bends were tested by using hardness tester, cupping machine and impact testing machine, respectively. It shows that the best heat treatment process of the X70 grade pipeline steel bends is quenching at 890 °Cand thermal insulation for 26 min then water cooling followed by tempering at 590 °C and thermal insulation for 60 min then air cooling. Furthermore, the resulting hardness, yield strength, tensile strength, yield ratio, elongation and impact absorbing energy reach HB230, 595 MPa, 725 MPa, 0.82, 28% and 300 J respectively, which has excellent comprehensive mechanical properties.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
