depends on the polymer you are using, most come at the required dry weight when you order the granules. polymer granules do not absorb moisture, so unless you have a leak in your factory above the hopper you shouldnt need a drier at all. rubber is a differnet animal and has to be dried to a given weight per product regarding flex and finish. have manufactured everything from plastic pots to clear ploycarbonate in injection molding and also in clear sheet blow molding like crush cups, never had a drier ever except for rubber pellets.
If rubber is your product like soles for shoes, thongs etc, then Technical research and services used to make such driers, TRS.
Sorry if this sounds condescending, but the answer is to use your brain.
For the given job, you will need to understand the end result of plastic processed. (combination of cycle time, shot size, and so on)
Given that you then know how much plastic to process per hour, consider the dyring properties of the plastic you intend to use. Most require a 4 hour residence time in dryers, but some need 6 hours. This can depend on the pellet size.
Then you need to understand the humidity and expected moisture content of the pellets at your location. This will let you understand how much moisture you need to remove (per hour) from the incoming pelets.
Do a little bit of maths and you end up with minimum requirements.
In reality, you would get a dryer suited to the maximum capacity of your moulding machine and sets of hoppers to suit the quantities of different materials you will process.
If you are into larger continuous runs, then you could probably receive the material dried and keep it in dry silos at your site which then only requires a final dryer at teh machine.
As much as you can (or cannot) trust them, ask a salesman.
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Just an Engineer from the land down under.
Plastic Injection Moulding
Re: plastic injection moulding
