Introduction of several common annealing processes for stainless steel pipes
By: mxgy,
Do you know anything about the annealing process of stainless steel pipes? The annealing of stainless steel pipes has three main purposes: ① reduce the hardness of stainless steel, improve the plasticity of steel pipes, facilitate cutting and cold deformation processing; ② grain refinement, uniform structure and composition of stainless steel, improve its performance, and prepare for heat treatment; ③ eliminate Residual internal stress prevents cracking and deformation.
The annealing process of stainless steel pipes is not single. It has many methods according to different requirements of the workpiece. The common annealing processes are stress relief annealing, complete annealing and spheroidizing annealing, etc.
1. Stress relief annealing
The most common equipment for stress relief annealing is the stainless steel tube continuous bright annealing furnace, and the ammonia decomposition furnace is used for the protective gas source and is equipped with a gas purification device. The transmission method can be selected according to the needs of users. Stainless steel mesh belt or stainless steel belt transmission. Stainless steel tube continuous bright annealing furnace has advanced control, significant energy saving and easy maintenance. The heating zone of the whole line adopts PID automatic multi-zone temperature control. Place the stainless steel strip neatly and evenly on the feeding rack, transport it into the annealing furnace through the conveyor belt, heat it to 1050~1080°C under the protection of a controlled atmosphere, and keep it warm for a short period of time, all the carbides can be dissolved to austenite In the solid structure, and then rapidly cooled to below 350 ° C, a supersaturated solid solution can be obtained, that is, a uniform unidirectional austenite structure.
2. Fully annealed
Complete annealing is suitable for refining the coarse superheated structure with poor mechanical properties after casting, forging and welding of medium and low carbon steel. The workpiece is heated to 30-50°C above the temperature at which ferrite is completely transformed into austenite, kept for a period of time, and then slowly cooled with the furnace. During the cooling process, austenite is transformed again, which can make the steel structure thinner.
3. Spheroidizing annealing
Spheroidizing annealing is suitable for reducing the high hardness of tool steel and bearing steel after forging. Heat the workpiece to 20~40°C above the temperature at which the steel begins to form austenite, and then gradually cool after keeping warm. During the cooling process, the lamellar cementite in the pearlite becomes spherical, thereby reducing the hardness.
Introduction of several common annealing processes for stainless steel pipes
By: mxgy,
Do you know anything about the annealing process of stainless steel pipes? The annealing of stainless steel pipes has three main purposes: ① reduce the hardness of stainless steel, improve the plasticity of steel pipes, facilitate cutting and cold deformation processing; ② grain refinement, uniform structure and composition of stainless steel, improve its performance, and prepare for heat treatment; ③ eliminate Residual internal stress prevents cracking and deformation.
The annealing process of stainless steel pipes is not single. It has many methods according to different requirements of the workpiece. The common annealing processes are stress relief annealing, complete annealing and spheroidizing annealing, etc.
1. Stress relief annealing
The most common equipment for stress relief annealing is the stainless steel tube continuous bright annealing furnace, and the ammonia decomposition furnace is used for the protective gas source and is equipped with a gas purification device. The transmission method can be selected according to the needs of users. Stainless steel mesh belt or stainless steel belt transmission. Stainless steel tube continuous bright annealing furnace has advanced control, significant energy saving and easy maintenance. The heating zone of the whole line adopts PID automatic multi-zone temperature control. Place the stainless steel strip neatly and evenly on the feeding rack, transport it into the annealing furnace through the conveyor belt, heat it to 1050~1080°C under the protection of a controlled atmosphere, and keep it warm for a short period of time, all the carbides can be dissolved to austenite In the solid structure, and then rapidly cooled to below 350 ° C, a supersaturated solid solution can be obtained, that is, a uniform unidirectional austenite structure.
2. Fully annealed
Complete annealing is suitable for refining the coarse superheated structure with poor mechanical properties after casting, forging and welding of medium and low carbon steel. The workpiece is heated to 30-50°C above the temperature at which ferrite is completely transformed into austenite, kept for a period of time, and then slowly cooled with the furnace. During the cooling process, austenite is transformed again, which can make the steel structure thinner.
3. Spheroidizing annealing
Spheroidizing annealing is suitable for reducing the high hardness of tool steel and bearing steel after forging. Heat the workpiece to 20~40°C above the temperature at which the steel begins to form austenite, and then gradually cool after keeping warm. During the cooling process, the lamellar cementite in the pearlite becomes spherical, thereby reducing the hardness.
