The turret is castellated, then welded through the flat plate in 4 x places and re-dressed. See image attached
The weld is not complete around the inner circumference. The mating surfaces are very close and initial appearance would show the powder coating treatment performing a seal, but this is no guarantee of gastight performance. The gastight seal of this design plate is intended to be between the flat plate and the floor surface
Hop the above helps answer your query
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