METHOD FOR JUDGING QUALITY OF DIE CASTING PRODUCT AND INSTRUMENT THEREFOR

摘要

PROBLEM TO BE SOLVED: To quicken the judgement of quality and to improve the productivity by measuring the forming time of a die casting (molten metal injection time) and gas vol. discharged from a die at the time of forming, comparing preset reference values and executing the judgement of quality. SOLUTION: The time T1 when the molten metal injected with a plunger 12 reaches a gate 5 or a runner 6 and the time T2 when the molten metal fills up a cavity 7 and reaches a gas vent passage 8, are detected and at the same time, the gas vol. V discharged from the gas vent passage 8 during this period is measured and inputted to a quality judging means 20. The quality judging means 20 compares whether the passing time T3 subtracting the time T1 from the time T2 and the discharged gas vol. V are in the range of the preset values or not, to judge the quality. A die casting product is cast by using the quality judging means 20 to the time and the gas vol. of the quality judging reference and the times T1 , T2 and the gas vol. V at this time are actually measured and also, a non-destructive test and a destructive test are executed to decide the quality.