What Is The Purpose Of Annealing Sanitary Seamless Pipes

Why does 316 sanitary seamless pipes needs to be annealed

With the wide application of stainless steel in all walks of life, especially in food processing, food machinery, dairy products and other industries, as the market’s quality requirements for stainless steel pipes are becoming more and more demanding, the product’s smoothness, outer diameter and wall thickness deviation far from reaching the requirements, as a sanitary pipe fittings supplier, wellgreen always supply annealed sanitary seamless pipes.

Annealing Sanitary Seamless Pipes

Simply put, there are two types of annealing: A, ordinary annealing, B, bright online annealing

The purpose of annealing 316 seamless stainless steel pipe includes the following three aspects:

  • (1) Reduce hardness and improve machinability;
  • (2) Eliminate residual stress, stabilize size, reduce deformation and crack tendency;
  • (3) Refine the crystal grains, adjust the organization, and eliminate organizational defects.

In production, the annealing process is widely used.

Depending on the purpose of annealing the workpieces, there are many annealing process specifications. Commonly used are complete annealing, spheroidizing annealing, and stress relief annealing.

  • 1. Complete annealing. Used for refining the coarse superheated structure of medium and low carbon steels with poor mechanical properties after casting, forging and welding.
  • 2. Spheroidizing annealing. Used to reduce the high hardness of tool steel and bearing steel after forging.
  • 3. Isothermal annealing. It is used to reduce the high hardness of some alloy structural steels with high nickel and chromium content for cutting.
  • 4. Recrystallization annealing. It is used to eliminate the hardening of metal wires and plates during cold drawing and cold rolling (increased hardness and decreased plasticity).
  • 5. Graphitization annealing. Used to make cast iron with a large amount of cementite into malleable cast iron with good plasticity.
  • 6. Diffusion annealing. It is used to homogenize the chemical composition of alloy castings and improve their performance.
  • 7. Stress relief annealing. Used to eliminate internal requirements for steel castings and welded parts.