CEV=C+Si/30+(Mn+Cu+Cr)/20+Ni/60+Mo/15+V/10+5B=0.21
The API X90 was bended at 1000 ℃ with the bend angle of 7 °, and then tempered at 560 ℃. It is noticed that water cooling online at the same time during the bending process, the detailed hot induction bending parameters shown in Table 2. The bending process and the position of neutral axis and weld joint is shown in Fig.1.
Table 2 Hot induction bending parameters of X90 pipeline steel.