Secondary Cooling System

For fouling prevention

In order to prevent corrosion, scale and slime, conventional methods of water treatment using chemicals have prevailed. However, because of recent wide-spread use of engineering plastics whose melting points are higher than previous materials used, conventional water treatment is no longer sufficient.
Functional Fluids developed the secondary cooling system as a new control method for cooling water in injection molding processes, which still satisfies today’s requirement for highly efficient cooling processes. Our new system has evoked great response in the field of mold injection.

【Fig-01 Comparison of cooling system】

Secondary cooling system

The secondary cooling system consists of two water-circulating loops: one is the cooling tower loop (the primary cooling water) and the other is the machine cooling-water (the secondary cooling water). The former loop provides cooling water to the UWT Cooling Unit from the cooling tower and the latter enclosed loop provides water to molds, chillers, molding machines and temperature regulators.
The UWT Cooling Unit has been developed in order to introduce the Secondary Cooling System easily. All you need to introduce the Secondary Cooling System are integrated into the UWT Cooling Unit. You can convert the exiting cooling system into the secondary cooling system only by connection of plumbing.

Effect of the secondary cooling system on fouling prevention

【Fig-02】 shows photos of the heat-exchanger plates which had been used for a year; the left hand photo shows the surface facing the cooling-tower water (the primary cooling water) and the right hand side shows the surface facing the machine cooling water (the secondary cooling water). There is a great deal of burnt umber deposit on the cooling-tower side. On the contrary, on the machine cooling-water side there is no fouling and the surface still has metallic luster. From these photos, you can easily confirm that there is no rust or scale despite of the use for a year. In addition, plate heat-exchangers are easily decomposed to remove the deposit on the cooling-tower side.

Results brought about by the secondary cooling system

● Advance in quality
The rejection rates are decreased and cycle times are cut down because the cooling process is kept rust free and scale free.

● Wide range of applicability
The Secondary Cooling System is applicable to high mold temperature for engineering plastics. Its fouling-prevent function works well at high water temperature over 100℃. High-level fouling prevention，which is required by precise plastic molding today, is attained without labors for troubleshooting or maintenance.

● Cost reduction
The secondary cooling system makes it possible to use cooling towers without fouling. The power required for cooling towers is so low compared to chillers that you can save a great amount of electrical cost by replacing chillers by cooling towers. In addition, UWT Cooling Unit has various energy-saving functions. For example, pumps and fan motors can be switched depending on the heat load and the ambient temperature, and revolution speeds are controlled using inverters to attain the minimum use of electricity.