Overview
This seminar provides comprehensive information about the Liquid Silicone Rubber (LSR) injection molding process and covers both the underlying engineering principles as well as their application in the molding environment. Classroom lectures cover the basics of the silicone materials, injection molding process, part design, and provide practical analyses that yield results and can be applied in the molding shop.
Injection molding workshops supplement the class material to provide experience with actual machine operation and practical molding techniques. Machine start-up, operation and shutdown procedures are demonstrated. Molding trials that show the relationships between processing variables and part quality are conducted.
Audience
This course is appropriate for sales managers, account managers, sales and applications engineers, new product development specialists, product marketing professionals, product designers and engineers, industrial designers and industrial engineers, mechanical engineers, materials purchasing managers, manufacturing personnel and technicians, plant managers, production supervisors, quality assurance and quality control personnel, and anyone involved in silicone part or mold procurement.
Content
Introduction to Silicone Materials - Liquid Silicone Rubber focused
- Overview of silicone materials comparing Liquid Silicone Rubber (LSR), Room Temperature Vulcanizing Silicone (RTV), and Heat Cured Rubber Silicone (HCR).
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Basic silicone structure, overview of properties and applications.
- Discussion of thermoset vs thermoplastic materials.
- Introduction to silicone viscosity and curing as applicable to injection molding.
Introduction to Liquid Silicone Injection Molding Process
- Walkthrough of liquid silicone rubber injection molding process. Discussion of silicone mixing/feeding, shot size, filling/flow, and hold/pack.
- Discussion of filling problems; venting/vacuum, thermal effects, flow length, orientation, runner and gate flows, flow balancing, pressure profiles, discussion of curing and pressure-volume-temperature (PVT) behavior.
Liquid Silicone Rubber Injection Mold Considerations
- Mold types and configurations: 2-plate, 3-plate, stack, etc.; heating, ejection, and cold runner system.
- General Design for Manufacturing (DFM) - Undercuts, parting line, fill, and venting.
- Overmolding Design Considerations - Approaches, materials, and considerations.
Process Setup and Troubleshooting
- Liquid Silicone Rubber molding and machine concepts, troubleshooting; cycle-time minimization and yield.
Workshops
Attendees will use hydraulic molding machine and non-instrumented molds.