How injection moulding works

0:06 The following sequence illustrates the basic functions of an injection moulding machine in the process by which plastic pellets are transformed into molten parts.

0:17 Pellets are fed into the Hopper

0:20 A screw conveys and melt the pellets within the barrel.

0:24 Melted polymer is forced into the closed mould.

0:28 The parts are formed

0:30 The polymers cooled within the mould

0:33 The mould is opened, the part is ejected or removed from the mould and the next cycle begins.

0:47 It is important that production personal are able to recognize common moulding defects. Excessive unwanted material located on the edge of the part is referred to as flash.

0:58 This is a result in material passing between mould components, usually the parting line. Flash most commonly results from high injections and packing pressures or low clamp tonnage.

1:13 The incomplete filling a mould cavity is called a short shot, increasing the amount of plastic entering the mould during the injection or cleaning the mould bands usually correct this issue.

1:29 Designing and constructing an injection mould can be an expensive and time consuming process. Moulds extremely valuable tools it must be properly care for before, during and after production.

1:42 Good general mould maintenance can help avoid costly repairs and retooling. Before moulding operation begins, the mould should be closely inspected for any damage that is cracks, leaks or rust.

1:59 All moving components should be checked for excessive “wear”, This is usually evident by streaks or grooves any found should be prepared by a trained professional

2:10 Most moulds contains venting on the cavities, runners and gates and should be thoroughly cleaned with a cloth rag or a cotton swab