| 摘要 |
PURPOSE:To pack molding sand into inner part of a lost foam pattern at high density and to simply cast a cylindrical casting having bend without any casting defect by fitting sand packing jigs having the specific construction at both end parts of the lost foam pattern at the time of casting the cylindrical casting having bend with full mold casting method. CONSTITUTION:At the time of casting the hollow cylindrical casting having bend with the full mold method, on the opening parts at both ends in the lost foam pattern 2 formed with polystyrene foaming material, etc., the sand packing jigs 1 arranging plural tapered holes 1a having 20-30 deg. tapered angle so as to become smaller hole diameter toward hollow part 2a in the pattern 2 are fitted. A runner 4 having a sprue 3 is set in the pattern 2 and embedded into the molding sand 6 in a flask 5 and the molding sand 6 is made to ram around the pattern 2 with a vibrator 7 and also packed into the hollow part 2a in the pattern 2 from one side of the tapered hole 1a. Under this condition, by pouring molten metal into the pattern 2 through the runner 4, the pattern is burnt and vaporized and the molten metal is cast and solidified. |
