Two Shot Molding

Two shot moulding, also called double shot injection molding, double shot
moulding , multi shot injection molding or 2k injection moulding is one
category of injection molding using two different thermoplastic materials to
produce injection molded parts in two colors or two components in the double
injection molding process to produce 2 shot molding in large quantities
quickly, economically and efficiently. Multi multi injection molding has
characteristics as below:

Two shot injection molding, co-injection, two color injection molding and multi
component injection molding are all variants of advanced molding techniques.
A combination of hard plastics and soft materials.
Two-step process is executed in a single press cycle.
Combine two or more components to eliminate additional assembly costs.
Keyplast as top of 2 shot injection molding companies, with years of expertise
and cutting-edge technology, we offer precise and efficient 2 shot injection
molding solutions for a wide range of industries. Our skilled team and state-
of-the-art facilities ensure top-notch quality and fast turnaround times. Trust
KeyPlast for your complex multi material injection molding needs. Contact us
today to discuss your project and experience the excellence of KeyPlast's
double shot molding capabilities.

Two Shot Molding Process
Two shot injection molding has two stages in the whole process.

Firstly one shot of materials is injected into a mold and cooled to form a
solid part. Secondly, the mold opens and rotates 180 degrees and then closes.
The second shot of materials is injected into the mold, through or around the
first molded part. After sufficient cooling, the mold opens and the multi-resin
molded part is ejected. 2 shot moulding has key factors as below:

Melting temperature for the materials
Wall temperature for the mold
Injection speed for the molded parts
Delay time between injections
Temperature of the components

Two Shot Injection Molding Design Guide
The mold used in two shot molding consists of different tool sets. In rotating
platen settings, these two shot injection molding tools share the same core,
but different cavities. The runner must be designed to close during its
inactive forming step.

Wall thickness is an important two shot molding design consideration when
designing parts for a number of reasons:

Due to the molding pressure from the second step, the substrate wall should be
thick enough to withstand the force without collapsing.

Walls should not exceed traditional thickness guidelines to produce effects
attributable to irregular cooling.

To ensure accurate and thorough flow of 2k molding material into all parts of
the cavity, the wall thickness should not fall below a certain minimum value.

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