With the increasing demand for stainless steel pipes in domestic and foreign markets, customers' requirements for stainless steel pipes are becoming stricter. Annealing of stainless steel tubes during forging and drawing is an indispensable process, and bright annealing is particularly important. The bright annealing of the stainless steel tube is mainly the heat treatment of the finished product under the protective atmosphere by the bright annealing furnace. However, many users tend to anneal stainless steel tubes that are black or not completely bright. Today, Hangao Tech (SEKO Machinery) will discuss the reasons and solutions for the annealing of stainless steel tube annealing furnace.
The continuous single pipe stainless steel tube bright annealing furnace produced by our company mainly has two kinds of structures: Zhijin type bright annealing furnace and intelligent heat preservation bright annealing furnace. These two structures are all online equipment on the welded pipe production line. They are composed of heating furnace body, cooling water tunnel, conveyor belt device and ammonia decomposing furnace. They can continuously process stainless steel welded pipes without interruption to achieve better sealing and reduce energy consumption.
The main reasons for the annealing of stainless steel tube annealing furnace are as follows:
1. The problem of the annealing furnace itself: whether the structure of the furnace is reasonable and whether the airtightness is good. The heating section should be a sealed cavity that is isolated from the outside air and does not run out of gas or water.
2. The stainless steel tube itself has too much oil or water stain, so the protective atmosphere inside the furnace is destroyed, and the purity of the protective gas is not reached.
3. The problem of ammonia decomposition furnace, the ammonia decomposition furnace must be equipped with purification equipment, so that the decomposition gas has high purity.
4. The annealing temperature is not enough. The annealing temperature of the 300 series stainless steel tube is generally 1050 °C-1080 °C. If it is lower than this temperature, the tube is also unblinkable.
5. The temperature after cooling is too high. After the high temperature annealing and cooling of the stainless steel tube bright annealing furnace, it is very bright in the gas protection environment. For some reasons, the temperature of the tube after the furnace is still high, so exposed The air is slowly getting dark.
If the above points are excluded, the stainless steel tube that has been opened for about ten seconds should be brightened, brighter than before annealing, and brightly reflective.
