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, furnace bottom: double sandwich structure and cylinder head assembling and welding the water as a whole, equipped with a casting platform, furnace bottom there is a welding columns support the furnace and the furnace joint fixed.