It was validated that p-Q

2

diagram relationship between the feed oil circuit and the return oil circuit of the shot end system of the die-casting machine is accordant based on p-Q

2

diagram principle.Relationship between p-Q

2

diagram of die casting die and the shot end system was expounded

and simulated ways for trial-die were described using p-Q

2

diagram

in which the evaluation and modification of flow coefficient were considered.The practical validation of p-Q

2

diagram has been conducted by producing cylinder using Buhler machine.