Whether the annealing temperature reaches the specified temperature, Stainless steel heat treatment is generally taken solid solution heat treatment, that is, people commonly called “annealing”, the temperature range of 1040 ~ 1120 ℃ (Japanese standard). You can also observe through the annealing furnace observation hole, the annealing area of the stainless steel tube should be incandescent, but there is no softening drooping.
Annealing atmosphere, generally is the use of pure hydrogen as annealing atmosphere, the atmosphere purity is better than 99.99%, if the atmosphere is another part of the inert gas, the purity can be a little lower, but must not contain too much oxygen, water vapor.
Tightness of furnace body, Bright annealing furnace should be closed, isolated from the outside air; With hydrogen as the protective gas, only one vent is open (to ignite the discharged hydrogen). The method of inspection can be used in the annealing furnace with soapy water in each joint gap, to see whether the gas run; One of the most easy to escape the place is the annealing furnace into the pipe and out of the pipe, this place is particularly easy to wear the seal ring, to be often checked and often changed.
Protective gas pressure, In order to prevent micro-leakage, the protective gas in the furnace should maintain a certain positive pressure. If it is hydrogen protective gas, it is generally required to be more than 20kBar.
Water vapor in the furnace, On the one hand, check whether the furnace material is dry, the first furnace, the furnace material must be dried; Two is the stainless steel pipe into the furnace whether residual too much water, especially if there is a hole above the pipe, do not leak into, otherwise the furnace atmosphere is destroyed.
Want to note basically is these, normal words, after opening furnace should return 20 meters the stainless steel tube of the left and right sides will begin to shine, bright get the kind that reflects light.
Post time: Sep-19-2023