Exothermic riser positioning and clamping structure placed on upper mold without support

The utility model relates to the technical field of exothermic risers, in particular to an exothermic riser positioning and clamping structure placed on an upper mold without a support, and provides the following scheme aiming at the problem that an exothermic riser in the prior art cannot be conveniently placed on the upper mold under the condition of no support: the exothermic riser positioning and clamping structure comprises a knock-off core sand core and an exothermic riser, a connecting opening is formed in the top face of the knock core sand core, the bottom of the exothermic riser is glued to the top of the connecting opening, and a plurality of interference strips arranged in the axial direction of the exothermic riser are arranged on the inner ring of the exothermic riser. The knock-off core sand core and the exothermic riser are combined into a whole, and a local interference structure is adopted, so that the problem of placing the exothermic riser under the condition that an upper mold is not supp