Said to offer vacuum compression molding, hot-cold presses, sandwich molding
, presses to mold friction parts, presses in clean rooms, SMC, BMC, etc.
However, since 2004 Bemis has combined sandwich molding
with multi-shot molding--for example, co-injecting a steering wheel part with a glass-filled recycled PP core and a virgin PP skin without glass, then over-molding the part with a different color and material for a soft-touch surface.
was carried out in a Meiki M-200A II-MJ at a mold temperature of 40[degrees]C, a barrel temperature of 200[degrees] C, an injection time of 10 s, and a cooling time of 25 s.
showed off an updated sandwich molding
system, The company has long offered this technology for simultaneous injection of core/skin structures with foamed or regrind core and solid virgin outer layer.
Although there exists a surprisingly large amount of art and science dealing with the complexity of inherent encapsulation and interface phenomena occurring under processing environments, numerical modeling of sandwich molding
is still in the embryonic stage.
According to Joe McRoskey, chief executive officer of Co-Mack Technology, co-injection molding, also referred to as sandwich molding
, involves simultaneous injection of two materials from two separate injection units through a specially designed nozzle into the mold, creating a skin and core in the molded part.
The machine has two electrically driven injection units for multi-component sandwich molding
and hydraulic two-platen clamp that can handle indexing molds.
The pressure control sandwich molding
experiments were conducted using the transfer molding process.
Novel Process Technology * Product-by-process * Sandwich molding
(co-injection) * Programmed injection rate * Coining/variable volume packing * Injection-compression molding * Moving cavity boundaries
For this article, we'll define the two general approaches as sandwich molding
Mold filling studies of sandwich molding
have been reported by some authors (e.
Other innovations included foam-core sandwich molding
(the ICI process), which involved simultaneous coinjection of solid skins and a foamed core.