Exothermic and insulated riser

The utility model provides an exothermic insulated riser which comprises a riser body and a steel sleeve assembled on the riser body, the upper end and the lower end of the steel sleeve are open, and a flanging structure bent inwards is arranged at the opening of the lower end of the steel sleeve. Through the turnup structure, on one hand, the strength of the opening in the lower end of the steel sleeve can be increased, the steel sleeve cannot deform, and on the other hand, a small amount of materials can be prevented from falling into a cavity; the problems that the mold rusts, impurities exist on the surface of the sand mold, and defects exist on the surface of a cast product due to the fact that materials fall to the surfaces of the mold and the sand mold from an inner cavity of the steel sleeve can be effectively solved. 本实用新型提供了一种发热保温冒口，发热保温冒口包括冒口本体和装配在冒口本体上的钢套，钢套的上下端开口，其中在钢套的下端开口处设有向内弯折的翻边结构。本实用新型通过翻边结构，一方面可以增加钢套的下端开口的强度，其自身不会产生变形，另一方面可以用来阻止少量材料掉入型腔中，可以有效消除因材料从钢套内腔掉到模具和砂型表面所导致的模具生锈、砂型表面有杂质、浇铸后产品表面有缺陷等问