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Plunger-Plunger injection Moulding Machine

√ As the plastic industry developed a second type plunger machine appeared. known as two stage plunger.
√ This type of equipment involved two plunger units set on top of other the one to plasticize the material and feed it to another cylinder that consist of a chamber to heat the plastic material by conduction and plunger that operates as a shooting plunger and push the plasticize material into the mould.

Advantages 
 • Faster than conventional machine (single plunger) .
 • No Pressure loss encountered in compacting the granules. 
 • Allows larger parts with more projected area.
Disadvantage : 
• Extra construction for pre plasticizing so cost is more.

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