Mid-Platen LSR Mold | 3-Platen Mold for Valves & Frame Seals | TYM

Mid-Platen Mold (3-Platen): Built for Complex Ejection Requirements

The mid-platen mold adds a third platen to the standard 2-platen structure, enabling more flexible push-out and blow-out ejection mechanisms. This additional middle platen allows better control over the demolding path — particularly useful for parts with complex geometry, unusual demolding directions, or those requiring air-assisted ejection.

For frame seals and valve components, the demolding method often directly determines part yield and surface quality. TYM's mid-platen mold designs account for the elastic nature of silicone, using carefully engineered push-out/blow-out layouts to minimize tearing and deformation risk, ensuring consistency across production runs.

Key Advantages

● 3-platen structure enables flexible demolding for complex geometries

● Push-out/blow-out mechanisms reduce tearing, improving surface pass rate

● Suited for stable mass production of medium-to-large silicone structural parts

● Compatible with automated robotic arms for unmanned part removal

Typical Applications Frame seals, valve components, and medium-to-large silicone parts requiring air-assisted demolding.

Industry	Typical Products
Medical Devices	Multi-cavity respiratory valve discs, one-way valves, small seals
Baby Care	Multi-cavity pacifiers, breast pump valves
Auto Electronics	Sensor seals, small connector seals (requiring high multi-cavity consistency)
Diving Equipment	O-ring seals, small valve discs

 

The core value of the mid-platen mold lies in thermal isolation between the hot runner and the cold cavity plate, combined with needle-valve hot runner point gating — ideal for precision small parts requiring synchronized multi-cavity production with strict fill balance and consistent packing pressure across cavities, a common challenge for medical valve discs, multi-cavity pacifiers, and automotive sensor seals.

 

Applications of Mid-Platen 3-Platen LSR Molds

Mid-platen and 3-platen LSR molds are used for liquid silicone rubber parts that require special part release, thin-wall structures, valve features, connector sealing, or multi-cavity molding layouts. TYM supports mold engineering for silicone valves, frame seals, connector seals, diaphragm components, and other precision silicone molded parts.

Medical Needle-Free Injection Connector Seal

A self-sealing silicone septum molded with the mid-platen structure for tight dimensional consistency across cavities. This type of part is used inside needle-free injection connectorsand IV access ports, where the silicone must reseal itself after repeated puncture without leaking.

Automotive Wire Harness Connector Seal

A multi-pin cable seal strip molded in a mid-platen mold, with dozens of individual sealing holesformed precisely in one shot. Installed inside automotive wiring harness connectors, this seal keeps moisture and dust out of the electrical contacts.

Breast Pump Accessory

Soft silicone diaphragm/valve cups produced in a multi-cavity mid-platen mold for consistentwall thickness and flexibility across every part. Widely used in breast pumps and milk-expression devices, where the silicone valve regulates suction and prevents backflow.

PPE Mask Exhalation Valve Discs

Thin, flexible one-way valve discs produced in a multi-cavity mid-platen mold, shown here still attached to the runner straight out of the press. The precise, uniform thickness ensures reliableopening/closing response, making these discs essential components in respirator and protective face mask exhalation valves.