injection pressure / packing pressure

[Anonymous]

Hello,

i have a hybrid plastic part with a zylindrical insert. I have simulated the part because i wanted to know the inner pressure on the insert.

I made two simulations with two different plastics. A PBT (standard) and a PBT with improved flow abilities.

The attachment shows two different diagrams of the pressure. The packing pressure is 50 Mpa. The filltime of the part 0,25 seconds (its a very small part: 20mm lenght) .

With the normal PBT i have a maximum pressure at the changing point from injection to packing at 60 MPa - but why is the maximum pressure with the PBT (good flow) appearing after 7 seconds? The maximum packiing pressure should be at the changing, am i wrong?

i hope you could help me

sincerly pbäuerlein

[Anonymous]

Hello, colleague,

Your pressure profile should be such:

0 sec - 50 MPa

7 sec - 50 MPa