What is the difference between online bright solid solution and annealing of stainless steel pipes

On-line bright solution and annealing are the most commonly used stainless steel pipe manufacturing processes. These two stainless steel pipe manufacturing processes are actually heat treatment of stainless steel pipes.

1. On-line bright solid solution

On-line bright solid solution refers to heating the stainless steel tube to a solid solution state at about 1100 degrees Celsius and maintaining a constant temperature to completely or basically dissolve the carbides, and then rapidly cooling the stainless steel tube to room temperature to obtain a carbon supersaturated solid solution.

This process will improve the toughness and corrosion resistance of stainless steel pipes, relieve stress and soften for further processing or forming. Solid solutions are generally used for products that require mechanical properties of stainless steel pipes. In other words, on-line solid solution is a process in the manufacture of stainless steel pipes, which is beneficial to the later processes of bending, flaring, and shrinking of stainless steel pipes.

2. Annealing

Annealing generally refers to a heat treatment process. Among them, the stainless steel tube is slowly heated to a certain temperature, kept for a long enough time, and then slowly cooled (generally using furnace cooling). The purpose of annealing stainless steel tubes is to reduce hardness and improve machinability. Eliminate residual stress, stabilize size, reduce deformation and crack tendency; it is a heat treatment process for stainless steel tubes to refine grain, adjust structure, and eliminate structure defects.

At the same time, annealing is divided into ordinary annealing and bright annealing. Normal annealing is annealing without a protective gas. Bright annealing is an annealing performed under protective gas conditions.

The difference between online bright solution and annealing is that online bright solution treatment is a series of treatments to improve the mechanical properties and hardness of materials, while annealing is only a heat treatment step for heat treatment and stress relief.

Generally speaking, in order to improve production efficiency, make the surface of welded pipes bright, and produce high-quality stainless steel pipes, it is necessary to implement an online bright solution treatment method to make the performance of stainless steel pipes in one step. Therefore, in a sense, they have a certain relationship. In fact, online bright solid solution is an upgraded version of annealing.