The contourof temperature control looks as rings, welded on to the internal cylinder in relation to each other with a step 30 mm, in a center with a step 25 mm.
There is a slot in each of rings.
These slots are displaced in relation to each other with a step 150 degrees. In the first ring - 0, in the second - 150, in the third - 300, in fourth - 90, etc.
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