The reason and solution of stainless steel tube not bright after annealing
Dec. 12, 2020
The reason and solution of stainless steel tube not bright after annealing
Stainless steel tube bright annealing furnace mainly has two structures: steel belt stainless steel tube bright annealing furnace and mesh belt stainless steel tube bright annealing furnace. These two structures are composed of heating furnace body, cooling water tank, stainless steel muffle furnace box, conveyor belt, conveying mechanism and ammonia decomposition furnace.
The reasons why the annealing furnace for stainless steel tubes are not bright are as follows:
1. Whether the structure of the annealing furnace itself is reasonable and whether the muffle tank is airtight. The muffle furnace should be a sealed cavity, isolated from the outside air to avoid air leakage and water leakage.
2. The stainless steel pipe itself has too much oil or water stains, which damages the atmosphere in the furnace and the purity of the protective gas is not up to standard.
3. Ammonia decomposition furnace. The ammonia decomposition furnace must be equipped with purification equipment to make the decomposition gas with high purity.
4. The annealing temperature is not enough. The annealing temperature of 300 series stainless steel pipes is generally 1050-1080. If it is lower than this temperature, the tube will not fade.
5. The temperature is too high after cooling. The stainless steel tube bright annealing furnace is very bright in the gas protection environment after high temperature annealing and cooling. For some reasons, the temperature of the tube is still very high after it is out of the furnace, so it slowly turns black after being exposed to air.
