Liquid Injection Molding Silicones via Scientific Molding
Fee: $1,345
Instructor: John Bozzelli
Who Should Attend:
Processors, product designers, mold designers, or anyone involved in, or considering becoming involved in, the production of injection molded silicone parts will benefit from attending this workshop.
Overview:
The course provides an industry overview as well as world-class molding strategies with technical details specific to molding with liquid silicone rubber (LSR). Scientific data-based molding will be covered with at-the-press training to setup, optimize, and correctly document the process. Learn to think like the polymer. The process will be documented with a "Universal" set-up sheet. This seminar concentrates on process optimization, separating first stage from pack & hold. The necessary variables are then documented to establish a "Production Process." The resulting setup sheet will work for a given mold on any appropriate press.
Workshop Outline:
- Industry introduction
- Purpose
- Perspectives on the plastics industry
- Size
- Profit margins
- What is your product?
- The components of a successful plastics application
- Concurrent engineering and its benefits
- The four processing categories
- Constant machine conditions vs. constant LIMS conditions
- Basics of the LIMS polymer and its flow charactistics, optimizing first stage
- Polymer types
- Source of plastics and LIMS
- Making LIMS and its characteristics relative to some other plastics
- Fundamentals of Liquid Silicone Rubber flow
- Applications to processing
- Using an injection molding machine as a rheometer
- Establishing first stage
- Two-stage molding
- Non-return/check valves
- Plastic flow videos, mold filling
- Plastic pressure, hydraulic and electric components/performance
- Basic hydraulics
- Hydraulic vs. plastic pressure
- Back pressure
- Intensification ratio
- Pressure loss
- Pressure loss documentation
- Gate seal vs. unseal
- Pressure vs. time responses
- Clamp force and platen wrap
- The injection unit from the LIMS's point of view
- The feed system and mixer
- The feed throat
- The barrel
- The screw, how to get melt uniformity
- Nomenclature
- How it is supposed to work
- The importance of melt temperature control and melt uniformity
- The nozzle and tip/alignment
- The mold
- Design
- Components
- Runners
- Venting
- Vacuum
- Cooling and vacuum
- Part removal
- The controller
- Function
- Barrel and mold temperatures
- Timing
- Vacuum control
- Velocities and pressures
- Screw rotation
- Ejection
- Clamp
- Closed loop
- Open loop
- Knowledge survey; evaluation and miscellaneous information
- Machine basics and safety
- Four machine components
- Pressures and temperatures
- Safety