Rotomolding processing plant tells you the cooling method in rotomolding!
At present, there are four methods of cooling in the rotomolding process, namely
I. Air only.
ii. air/water/air.
iii. water mist/air.
IV. Water spray only.
The following rotomolding processing plant to specifically analyze these four cooling methods.
I. Air only.
1, many molding plants prefer this method because it eliminates the problems of rust and contaminants caused by water.
2. Because of the slower cooling, this method is equally easy to control product size. However, it also represents an increase in production cycle time.
II. Air/water/air.
1、Cooling with air until the product has started to crystallize or crystallization is completed.
2, then cooling with water for a short time (1-5 minutes).
3, followed by air cooling until the gas blows the mold dry, which is the common form of cooling.
4、Due to the change of the surrounding environment and the delay of the cycle, frequent and careful observation is required when cooling with water.
Three, water mist / air.
1、If the water mist is fine enough, it will not make the mold cooling to produce sharp changes and make the product freeze, and the water mist can be applied during the whole cooling process.
2, aluminum mold thicker than steel mold and has a higher heat capacity, thus slowing down the effect of rapid cooling, thicker mold will also make the cooling time longer.
3, for nylon products, it is recommended to use faster cooling, because it helps to develop a finer crystalline structure and greatly improve the impact performance.
Fourth, only water spraying.
1, is used for rapid cooling or "more urgent", especially for PVC materials.
2, however, faster cooling can also be used for polycarbonate and cross-linked materials.
3, in a series of tests, with 5 mm of product heated to 190 ℃.
4、Then cooled by various combinations, the tests recorded from the starting temperature of 190℃ to the demoulding temperature of 80℃.
5、When cooling with water only, the whole cooling time was 20 minutes (large water volume and small water volume).
6、The total cooling time with ambient air only is 56 minutes, and the cooling time with water-air combination is 33 minutes.
7, the cooling rate will be affected by the conditions of the surrounding environment.
8, with forced air cooling rate in winter than in summer much faster.
