Patent ID: 8838264

Claim:
A mold designing apparatus comprising: a contacting surface pressure calculating portion adapted to calculate a distribution of a contact surface pressure of a mating surface of a model of a mold under a casting condition; a heat expansion amount calculating portion adapted to calculate a heat expansion amount of the mating surface of the model of the mold under the casting condition; a setting portion adapted to modify a shape of the mating surface of the model of the mold as an inverted shape based on the calculated distribution of the contact surface pressure and the heat expansion amount, wherein the inverted shape of a respective portion of the mating surface is defined as the shape of the respective portion which is inverted with a surface of the respective portion, in which no deformation by heat expansion exists, as an inversion center from the shape of the respective portion in which deformation by heat expansion does exist in response to an inversion rate in the respective portion, and wherein the inversion rate in the respective portion is calculated based on a product of the heat expansion amount and the contact surface pressure of the respective portion.