Water Assisted Injection Molding - new methods
of using water instead of gas to further reduce
time cycles of thick section tubular products.
Water Assisted Injection Molding (WAIM) is also based on
the PEP process.
The mold cavity is filled and partially
packed with plastic gas. Gas or water injection creates
the initial bubble, followed by water injection to
pack the cavity and then sequencing the opening of
a shut-off valve to enable the expulsion of molten
plastic to the secondary cavity. The secondary cavity
is then pierced to allow water to flow through the
gas channel(s) to cool the plastic. Water is then
drained from the cavity by gas pressure or by air
injection to dry the part before opening the mold
and ejecting the part.
