| 摘要 |
A riser sleeve (100) for use in a foundry molding operation has cylindrical body in which the side wall (14) that may be untapered or that may taper uniformly from the bottom to the top (12) of the body. The riser sleeve is characterized by a plurality of cavities (102) are formed on the side wall, extending from the top in an axial direction of the body. These cavities provide air gaps when the riser sleeve is inserted into a mold, decreasing heat loss at the interface between the riser sleeve and the mold. |
