Accurate and flexible control of mould temperature is an essential element in the modern injection moulding process. So, while large centralised chillers supplying a number of machines remain a common feature in many injection moulding operations, there is an increasing move towards systems capable of providing individual mould temperature control that are better able to meet the challenges of today’s high performance polymers and increasingly demanding processing conditions.
New control developments are also providing opportunities to better optimise mould cooling. Giorgio Santella, chief marketing officer of the Piovan Group, explains that, as the performance expectations of injection moulded polymer parts increases, more accurate control of mould temperature becomes a critical process factor. “The higher the expected mechanical performance of the plastic part, the more stringent the temperature range for the cooling water, and the more difficult the cooling cycle becomes altogether,” he says. “The quantity of cooling water circulating in the mould is now the most difficult process parameter to control. Moulds have many different fabrication and manufacturing characteristics that influence the cooling cycle considerably. The water flow must be adequately set. It cannot be too low or too high, as in both conditions the efficiency of heat exchange drops, sometimes to critical levels.”
Santella says temperature control today is still perceived as a simple process to accomplish, with the result that is often undertaken by poorly performing equipment. Both process control capabilities and effi ciency of operation are elements that are still undervalued. The latest line of thermochillers from Piovan Group company Aquatech – DigitempEvo – combines the functions of a temperature control unit (TCU) and a chiller in a small integrated device.
Read the complete article published on Injection World.