Which description matches Compression Moulding?

• A. A slug or sheet of plastic is placed between a two part mould which is then brought together under pressure and heat which cures the polymer.
• B. The molten plastic is injected into a metal mold.
• C. A hollow parison is inflated in a mold.
• D. The plastic is extruded and cooled.

Answer: (A)

Compression moulding forms a part by placing a preheated slug or sheet of plastic into a heated two-part mould, then closing the mould and applying pressure and heat until the polymer cures and takes the shape. That exact process—a slug or sheet in a two-piece cavity, with heat and pressure to cure the material—matches the description provided. The other descriptions refer to different processes: injecting molten plastic into a mold is injection moulding; inflating a hollow parison in a mold is blow moulding; extruding and cooling is extrusion.