The role of heat treatment of stainless steel pipe fittings and flanges is to improve processing performance, eliminate internal stress and prepare a good metallographic structure for final heat treatment. Heat treatment of stainless steel pipe fittings and flanges The heat treatment processes include annealing, normalizing, aging, quenching and tempering, etc.
Heat treatment of pipe fittings and flanges refers to a metal thermal processing process that changes the chemical composition and structure of the surface or interior of the material through heating, insulation and cooling in the solid state to obtain the required properties.
Explanation of terms for heat treatment of pipe fittings and flanges:
1. Normalizing: A heat treatment process in which pipe fittings and flanges are heated to an appropriate temperature above the critical point AC3 or ACM, maintained for a certain period of time, and then cooled in the air to obtain a pearlite-like structure.
2. Annealing: A heat treatment process in which the hypoeutectoid steel workpiece is heated to 20-40 degrees above AC3, kept warm for a period of time, and slowly cooled in the furnace (or buried in sand or lime) to below 500 degrees in the air.
3. Solid solution heat treatment: A heat treatment process in which pipe fittings and flanges are heated to a high temperature and maintained at a constant temperature in the single-phase zone to fully dissolve the excess phase into the solid solution, and then rapidly cooled to obtain a supersaturated solid solution.
4. Aging: After solid solution heat treatment or cold plastic deformation, the performance of pipe fittings and flanges changes with time when they are placed at room temperature or slightly higher than room temperature.
5. Solid solution treatment: fully dissolve various phases in pipe fittings and flanges, strengthen the solid solution and improve toughness and corrosion resistance, eliminate stress and softening, and facilitate continued processing and shaping.
6. Aging treatment: Heating and maintaining the temperature at the temperature where the strengthening phase precipitates, so that the strengthening phase precipitates, hardens, and improves strength.
7. Quenching: A heat treatment process in which pipe fittings and flange steel are austenitized and then cooled at an appropriate cooling rate so that the workpiece undergoes unstable structural transformation such as martensite in all or within a certain range of the cross section.
8. Tempering: A heat treatment process in which the quenched workpiece is heated to an appropriate temperature below the critical point AC1 for a certain period of time, and then cooled using a method that meets the requirements to obtain the required structure and properties.
9. Carbonitriding of steel: Carbonitriding is the process of simultaneously infiltrating carbon and nitrogen into the surface layer of steel.
10． Quenching and tempering treatment: It is generally customary to call the heat treatment that combines quenching and high-temperature tempering as quenching and tempering treatment.
11. Brazing: A heat treatment process that uses brazing material to heat, melt and bond two workpieces together.
Author: Maria Yang
Post time: Dec-28-2023