Molding

Vesta's advanced Liquid Injection Molding (LIM) process ensures speed, precision and cleanliness. We offer complete injection, insert and transfer molding services. Our modern systems include semi- and fully automated liquid injection molding presses coupled with automated material delivery systems. These systems include commercial and proprietary Vesta-designed machines.

The Molding Process

At Vesta, silicone is molded using three main methods: Liquid Injection Molding (LIM), transfer molding and insert molding.

Liquid Injection Molding (LIM) is a rapid process excellent for low to high volume, high precision applications. During LIM, pumping systems deliver a two-part liquid silicone (catalyst and crosslinker) directly into a mixer for homogenization. Using a relatively low pressure, the mix is then injected directly into heated mold cavities in as little as 3 to 10 seconds. Molding and vulcanization (curing) occur inside the mold cavities within 10 to 90 seconds due to the high mold temperature. This all takes place within a completely closed system, which helps assure cleanliness.

Benefits of LIM
Vesta's LIM process offers many benefits, including:

• Cleanliness with minimized contamination risk
• No material preparation labor
• Lower injection pressure
• Faster cycle rates
• Consistent part quality

Transfer molding requires separate pre-mixing of the high consistency silicone rubber on a two-roll mill. During transfer molding, a hydraulic ram displaces the pre-mixed rubber through gates and sprues into the mold cavities.

Insert molding uses an injection process to overmold a silicone or non-silicone part placed inside the mold cavity.