PET Packaging Network

Caps Injection

When referring to injected plastic caps, there is a wide variety of options depending on the use intended. The main types of caps are:

  • Standard caps
  • Caps with tamper evident security band
  • Flip-top caps
  • Disk-top caps
  • Snap-caps
  • Caps for mayo/ketchup type seasonings
  • Caps for oils or liquid sauces
  • Caps for use with herbs/spices
  • Caps with handle
  • Wide mouth caps
  • Pressure caps for buckets
  • Other caps

These caps can be injected either by Hot Runner or Cold Runner moulds, and may feature force ejection or unscrewing system. Releasing thee caps by means of unscrewing avoids damaging the internal thread and allows a sturdier design. The use of one system or another depends deeply on the design of the cap itself.

If the caps incorporate a tamper evident band, this band can be manufactured through injection or cutting process. In the case of the cut band, the mold life is longer than in the case of an injected band, but requires the cutting device, an additional piece of equipment to consider.

For flip-top cap molds, there’s a cap closing system that can be incorporated directly into the mould, prior to ejection. This avoids having to close the lids manually after the injection process is done.

At PET Packaging Network, we can offer molds and injection systems for the manufacture of all types of caps. If the cap incorporates an inner liner, we can also supply the equipment that cuts and applies these liners to the lids.

However, in the case that there were no injection operation, or the volumes didn’t justify the investment, we can study the devellopment of a mold and subsequent supply of caps directly from Asia.