Effects of lift velocity

structure size of lift tube on the flow morphology of mold filling were investigated by hydraulic simulation.It was found that a larger interior diameter （D

1

） is beneficial to rapidly and smoothly filling mold with a given working section （S

4

） of lift tube.S

1

/S

2

（ratio of interior section and out-section） should be lower than 1.6

and S

4

/S

2

ratio has the more significant effect on the flow morphology than the lift tube structure when D

1

（interior diameter） is lower than 50 mm.S

1

/S

2

should be lower than 3

and the lift tube structure has the more remarkable effect on the flow morphology when D1 is more than 50 mm

so the proper conic ingate can be used to optimize the lift tube structure but S

4

/S

2

should be lower than 25.