Mold and manufacturing method for hollow cast product with bottom

A static metal casting mold for large-sized hollow cast product having a bottom comprising:

• a top lid;
• an outer mold section including a lateral mold section and a lower mold section having at least one opening to serve as a sprue;
• a core to be disposed inside the outer mold section;
• the top lid attached to the core and covering the outer mold section;
• the lateral mold section of the outer mold section provided at its inner periphery with a composite cooling section to form an inner wall portion of the lateral mold section, by stacking chiller blocks and interposing therebetween refractory sands;
• the lateral mold section of the outer mold section provided at its outer wall portion with refractory sands,
• cooling pipes including plural sets of a first pipe and a second pipe,
• the first pipe extending longitudinally through the refractory sands at the outer wall portion, the second pipe extending longitudinally through the inner wall portion, the first and second pipes being connected at the respective lower portions,
• the second pipe being embedded in the chiller blocks so that the chiller block surface on the side to be contacted with a mold cavity will have enhanced cooling effect from fluid flowing in the pipes,
• each of the chiller blocks being free to expand when heated, owing to combined structure of the composite cooling section of the lateral mold section and the cooling pipes.