Thursday, May 20, 2010

Molding

Molding or moulding is the process of manufacturing by shaping pliable raw material using a rigid frame or model called a pattern.

A mold or mould is a hollowed-out block that is filled with a liquid like plastic, glass, metal, or ceramic raw materials. The liquid hardens or sets inside the mold, adopting its shape. A mold is the opposite of a cast. The manufacturer who makes the molds is called the moldmaker. A release agent is typically used to make removal of the hardened/set substance from the mold easier.

The terminology can depend on the application. Sand casting involves both a "pattern" (which is the positive-image model of the desired part) and a "mold" (which is the negative-image hole made by packing sand around the pattern).

Types of molding include:
  1. Compaction plus sintering
  2. Injection molding
  3. Reaction injection molding
  4. Compression molding
  5. Transfer molding
  6. Extrusion molding
  7. Blow molding
  8. Rotational molding
  9. Thermoforming
  10. Vacuum forming, a simplified version of thermoforming
  11. Laminating
  12. Expandable bead molding
  13. Foam molding
  14. Rotomolding
  15. Vacuum plug assist molding
  16. Pressure plug assist molding
  17. Matched mold