The brightness of the stainless steel pipe after annealing determines the quality of the product. There are also many influencing factors, and five important factors are listed for reference.
1. Whether the annealing temperature reaches the specified temperature. Stainless steel heat treatment are generally take the solid solution heat treatment, also is the people of the so-called “annealing” usually, temperature range is 1040 ~ 1120 ℃(Japan standard). The stainless steel pipe in the annealing zone should be incandescent, but it does not appear to soften and droop.
2. Annealing atmosphere. Pure hydrogen gas is usually used as the annealing atmosphere, atmosphere best is more than 99.99% purity, if the other part is an inert gas atmosphere, can also lower purity, but absolutely can’t have too much oxygen and water vapor.
3. Furnace sealing. The bright annealing furnace should be enclosed and isolated from the outside air. Only one vent is made of hydrogen gas, which is used to ignite the hydrogen gas.
4. Protect air pressure. In order to prevent microleakage, the protection of gas in the furnace should maintain a certain positive pressure. If it is hydrogen gas, it is usually required above 20kBar.
5. Water vapor in the furnace. On the one hand, it is necessary to check whether the furnace material is dry. Second, the stainless steel pipe of the furnace is still too much water stained. If there is a hole in it, don’t leak it, otherwise it will destroy the atmosphere of the stove.
Problem supplement:
Whether the annealing temperature reaches the specified temperature. Stainless steel heat treatment are generally take the solid solution heat treatment, also is the people of the so-called “annealing” usually, temperature range is 1040 ~ 1120 ℃(Japan standard). The stainless steel pipe in the annealing zone should be incandescent, but it does not appear to soften and droop.
Source: China Stainless Steel Pipe Manufacturer – wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)
Comments