Plastic mold compression molding process

Today and again on Monday, really summer heat ah, sunny bright and hot. Today, Dongguan Plastic mold factory editor for everyone to introduce the plastic mold compression molding process.

Compression molding process

1) Feeding

① feeding the key is the amount of feeding

Quantitative method:

Weight method: accurate, trouble

Capacity method: convenient but not very accurate

Piece method: preload the ingot, count into the count

③ reasonable stacking of plastic, powder or pellet stacking to be done in the middle of the high four weeks low, easy to gas emissions.

2) mold clamping

 Can be combined after the mold, mold clamping time generally from a few seconds to several tens of seconds.

 The mold clamping process is divided into two parts:

① punch touch plastic before: try to speed up the mold speed (shorten the cycle, to avoid premature curing of plastic)

② punch after touching plastic: slow down the mold speed (conducive to exhaust)

3) Exhaust

OBJECTIVE: To remove moisture and volatile matter from the byproducts of gases and chemical reactions to avoid affecting plastic parts and surface quality.

Method: After clamping to a certain pressure, immediately pressure relief, punch slightly raised, continuous 1 to 3 times.

Plastic parts with small metal inserts do not use exhaust operation, so as not to shift or damage.

Good plastic with a late pressure method, that is, from the punch and plastic contact to the mold completely closed in the process of pausing 15 to 30 seconds.

4) holding and curing

Holding time: The time it takes to remove the plastic from the presser to the pressure relief.

Note: The length of the holding time by the plastic type, warm-up situation, the shape of plastic parts and the degree of compression of the shadow

ring.

 requirements of the curing stage: the molding pressure and temperature to maintain a certain time, so that the cross-linking reaction to the required level.

5) stripping

Plastic parts stripping method:

The introduction of the machine automatically launched

Die outside the manual launch

The complex plastic parts are cooled to a certain temperature under pressure and then stripped

Note: The above information from the Jiezheng  mold on the Internet, welcome reproduced, indicate the source!