| 摘要 |
PURPOSE:To prevent generation of casting defects by packing a resin or adhesive agent which is expended at a prescribed temp. in the slits of a vent body and heating the slits to the prescribed temp. thereof or above, thereby decomposing and expending the resin or adhesive agent. CONSTITUTION:The slits 14 consisting of plural grooves 12 are formed to the slit vent 10 from the plane 10a to base 10b thereof. The plural grooves 16 are further formed by rolling to the circular cylindrical outside peripheral face 10d. After the adhesive agent 18 is packed into the slits 14, the slit vent 10 is mounted to the venting part of a die and the plane 10a is machined so as to be made flush with the cavity face. The adhesive agent 18 is decomposed and expended and the grooves 12 are opened when the vent 10 is heated up to the prescribed temp. by heating the die inside by a burner etc. Generation of deformation in the grooves 12 is obviated by the intervention of the adhesive agent 18 in spite of the compressive load exerted at the time of mounting the vent 10. Venting is, therefore, improved and the generation of casting defects is prevented. |
