Mold Temperature. The temperature of the precision mold is another essential consideration that affects the quality of the injection-molded part. Getting the best quality mold is a balance between heating the mixture sufficiently to create a homogeneous mixture and cooling it down at an ideal rate. Anything else would be undercooling or overcooling.
Undercooling and Overcooling Issues. Improper polymer flow is a direct consequence of under- or overcooling issues in plastic injection mould. When the mixture is not cooled sufficiently, it may not solidify completely before being ejected. This may leave residual plastic in the mold.
Conversely, excessive cooling causes a lack of uniformity in the plastic material. This may cause further problems down the line such as shearing, cracking and cavities that do not fill up completely. Maintaining the mold temperature at a set temperature will yield the most optimum results.
Temperature Control with an Industrial Chiller System
Close tolerance temperature control units can be used with industrial chiller systems to provide close temperature tolerances for process water. When combined with a compatible and suitably sized industrial chiller, the temperature control unit can maintain the process temperatures at ±0.5°F of the set 33°F value, ensuring a stable injection-molding process without catastrophic freezing failures.
The close tolerance temperature control units come in varying flow variations and configurations and standard models have a pump and heat exchanger with a jacketed tank or a heat exchanger.
Plastic moulding is the process of pouring liquid plastic into a certain container or mould so that it hardens in that customized shape. These plastic moulds can then be used for a wide range of purposed. There are 5 types of plastic moulding that is considered to be the most effective and most popular.
These 5 types are extrusion moulding, compression moulding, blow moulding, injection moulding and rotational moulding. We will look at the details pertaining to each of these methods so that you can decide which one will be the most effective for you to use.
1. Extrusion Moulding
With extrusion moulding, hot melted plastic is pressed through a shaped hole to create a lengthy shaped plastic part. This customizable shape that the liquid plastic gets pressed through is called a die. This die is custom made for the particular outcome that is desired. It is almost like pressing dough through a press to make shaped cookies.
The other forms of plastic moulding also use extrusion so get the raw liquid into the commodity mould, the difference here is that other methods use the moulds to make the desired shape and here the extrusion itself is making the shape with the use of the die’s shape.