3, bottom: with double water sandwich structure and the cylinder head welding as a whole, which consists of casting platform, bottom wall welded columns supporting the furnace and the furnace connection fixing.
3, bottom: double water interlayer structure and the cylinder head welding as a whole, with casting platform, the bottom are welded on the outer walls of column supported connecting furnace and furnace body is fixed with.
3, bottom: double sandwich structure and cylinder head assembling and welding of water as a whole, within the casting platform, bottom weld for outer wall columns supporting the furnace and furnace body mating fixture.