Annealing of cold drawn steel pipe: refers to metal material heated to the appropriate temperature, maintained a certain time, and then slowly cooled heat treatment process.Common annealing process: recrystallization annealing, stress annealing, spheroidizing annealing, complete annealing, etc.Annealing: the purpose of the main is to reduce the hardness of metal materials, improve the plasticity, processing and machining and pressure, and reduce the residual stress, improve the organization and composition of the homogenization, or for the heat treatment after ready for the organization, etc.

Quenching of cold drawn steel pipe: refers to heat the steel to the Ac3 or Ac1 point temperature (steel) above a certain temperature, keep a certain amount of time, and then in the appropriate cooling speed, get martensite bainite) (or heat treatment process of the organization.The common quenching processes include salt bath quenching, martensite quenching, bainite austempering, surface quenching and local quenching.The purpose of quenching is to obtain the required martensite structure, improve the hardness, strength and wear resistance of the workpiece, and prepare for the post-heat treatment.