Abstract
The method of taking a sample for determination of the oxygen in steel fresh from the furnace has not yet been established, although it has been the target of discussions.
This report treats of the results of the study conducted on vacuum sampling method which is almost perfect and comparatively simple in operation.
The sampler for vacuum sampling method is as shown in Fig. 3 and 4 and Photo. 1, and suction tube of the sampler has been made vacuous with its tip prepared as shown in Fig. 1
In case of determining oxygen content in steel in an acid open hearth furnace, vacuum sampling method has been closely similar with bomb method but apparently different from casting method, which has generally shown higher value.
While in case of a basic open hearth furnace, vacuum sampling method has shown a lower value than the cases of bomb method, suction method and casting method.
It is diffiicult to draw a conclusion from the experimental results because the amount of gas released during solidification of molten steel is variable with its chemical components, temperature and solidification condition. It is presumed that some amount of gas may be released when carbon content in molten steel is medium and silicon and manganese contents are low, but in most cases the amount of gas released has been within analytical error.
