2. Principle
• A plastic material is placed directly into a heated metal mold
then is softened by the heat and therefore forced to conform
to the shape of the mold.
3. Working
• The thermosetting plastic material is subjected to heat and
pressure in a single stroke.
• This is done by using a hydraulic press with heated platen.
• The actual temperature and pressure depends on the
properties of the thermosetting plastic material to be molded.
• The thermosetting plastic material in compound form is
placed in the cavity of the mold so as to fully filled the
impression of the mold.
• As the mold closes down under pressure, the material is
squeezed between the two halves of the mold and compact
to the shape of the impression.
4. Working
• The excess material flows out of the mold as a thin film
known as flash which is trimmed off.
• Under the influence of heat, the compacted mass gets cured
and hardened to the shape.
• The mold can be opened while still hot to release the molded
article.
• https://youtu.be/pOGpXZ-UMfo
7. References
• Plastic engineering handbook by Joel Frados.
• Polymer extrusion by hanser publication.
• Polymer processing by DH Morton Jones.
• Hand book of plastic technology by W.S. Allen/ P.N. Baker.
• SPI Plastics Engineering Handbook by Michael L. Berins.
• SBP Handbook of Plastics.
