Annealing is the American standard seamless steel pipe heated to slightly higher or lower than the critical temperature, to maintain a period of time (ie, insulation), and then slowly cooling a process. Common annealing process classification: diffusion annealing, complete annealing, isothermal annealing, spheroidizing annealing, incomplete annealing, recrystallization annealing, stress relief annealing.
American Standard seamless steel pipe annealing as follows:
(1) Reduce the hardness, improve machinability.
(2) Eliminate residual stress, stabilize size, reduce deformation and crack tendency;
(3) Grain refinement, adjust the organization, eliminate tissue defects.
(4) Uniform material organization and composition, to improve the material properties or for future heat treatment to do the organizational preparation.
