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  CITO Products, Inc.
N8779 Hwy. X
P.O. Box 90
Watertown, WI 53094
USA
Tel: 920-261-2606
Fax: 920-261-1350
sales@pulsecooling.com
support@pulsecooling.com
Technology
 

Warm Water vs. PulseCooling

 

Principle of Operation

1.- Each Molding Cycle induces Hot melt into the Cavity. Since there was no cooling applied during the ejection the thermal gradients are reduced. Thus the molten material from the next shot will flow more easily into the mold. The mold surface temperature is allowed to "spike" upward resulting in high gloss and good surface finish.

2.- The cavities are filled and the gate is frozen.

3.- A Mold Surface temperature sensor is located just below the molding surface. The temperature software analyses the thermal profile of the mold / melt temperature relationship and determines amount of cooling medium to be passed through the cooling channel. This cooling pulse matches the excess amount of heat to maintain thermal equilibrium to perfectly repeat the same molding condition.

4.- The cooling pulse of cold water from a cold water source (tower or chiller)

5.- The part is allowed to be "skinned" at the surface at a precise predetermined temperature thus reducing the sinks and allowing the part to shrink internally.

6.- Part is ejected.

Each cycle is continuously monitored and updated. All corrections are done during the molding cycle.

Note: Same amount of heat is removed with colder water in a shorter time = Cycle reduction

Questions and Answers about PulseCooling™  

1. How does PulseCooling  improve cycle time? By placing a sensor into the mold and controlling the mold surface temperature. Each molding cycle is cooled with a full flow cooling pulse, timed to match the exact cooling needs of each shot of melt, with coldest water available.

 2. How can PulseCooling produce better part quality? The PulseCooling cools during the first part of the molding cycle - just after the melt shot is completed when most heat is present (highest delta t) and shuts off the flow when cycle is near the end. The hot and cold spots (heat gradients) can dissipate (seek thermal equilibrium) this will produce a higher quality part since the shot was cured in a more uniform condition. 

3. Do I use the PulseCooling with my warm water circulator? No, the PulseCooling uses cooling water directly from the tower water supply or chiller.

 4. How can the PulseCooling improve the cycle when I have full flow? Full flow cooling is an uncontrolled cooling method, resulting in unpredictable parts. Typically a core requires more cooling then the cavity side of the mold. Cooling may be "on" continuously on the CORE side - while the CAVITY will be "on" a short time - just the right duration to remove the excess heat - thus maintaining the ideal mold surface and gate temperature. 

5. How and where do I install a sensor for best performance? A drilled hole will accommodate one of many sensor styles, which can be easily installed (detail information on sensor choice and placement in available upon request). A sensor is placed near the surface on core and cavity. The PulseCooling will test the mold for thermal responsiveness and "tune" itself to maintain the desired mold surface temperature. (Detail on installation instructions are available upon request and are included with each sensor)

 6. How many zones do I need for a typical 8 or 16 cavity mold? Typically 1 for the core, 1 for the cavity and if the tool has a hot runner or hot manifold, a separate zone is recommended to control the melt viscosity, gate temperature and the mold expansion.

7. How can 2 Zone PulseCooling control an 8 or more cavity mold? Each cavity receives the same amount of heat from the melt. Sensing the cooling needs of just one cavity provides the cooling information for cavities of the same size.

 8. Must a mold be redesigned to use the PulseCooling? No, the PulseCooling will enhance the performance of a poorly designed mold - and will give top performance when used with a well-designed mold. 

9. How can I Pulse Cool an existing mold without sensor holes? On an existing mold – without a sensor hole you may install an “internal wet probe” into the outgoing waterline. The PulseCooling software is designed to read the relative temperature in the waterline and thereby maintains the desired mold surface temperature.

 10. Will a PulseCooling prevent thermal expansion? Yes, by maintaining the mold temperature with continuous feed back to the PulseCooling thermal drift – thus steel expansion is eliminated

 11. What can I expect from a PulseCooling in general terms?

                • Consistently better part

 

                      • Consistently better cycle

                           • Reduced maintenance cost

                                  • Drastic reduction of chiller load

                                       • Fraction of operating cost

        • Reduced capital investment

 

ALL RESULTING IN AN EXCELLENT R.O.I.



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