This low temperature heating medium oil is used to control the cooling of the circuit. The medium oil returns after absorbing heat calories. The system controls the flow of the medium oil, returning it proportionally using a motor valve (control CV value of the solenoid valve via a DC input signal of 4 to 20mA), and drains it into the expansion tank. Subsequently, the system sucks the low temperature medium oil into the expansion tank and controls the cooling operation.

Advantageous Points Of Installing This Internal Cooling Circuit

As the temperature of the heating medium oil in the expansion tank is relatively low, oil deterioration by oxidation will slow and its service life will be extended.
The low temperature medium oil can also be used for cooling a canned pump stator and heat exchanger so that the service life of the canned pump can also be extended.

In Competitor's Systems, They Have To Equip A Heat Exchanger For Each Circuit And Control The Cooling Water To Limit The Temperature Of The Heating Medium Oil.

As disadvantages of this system A heat exchanger matching a controlling temperature will be required. (stationary tube and plate type, one side fixed type, U tube type, or double tube type heat exchangers) Such systems include two fluids with different characteristics, temperatures, and pressure flow; both inside and outside the heat transfer tube. Due to the thin thickness of a tube wall, continuous pressure variation, and uneven temperature dispersion, etc., these systems are very frequently prone to cracks in the wall, caused by stress and corrosion. Such cracks occur more frequently on walls made of excellent corrosion proof material (expensive). Other causes of these problems include residual stress, internal stress due to operational pressure, thermal stress due to temperature differences, and tensile stress.

When the flow of cooling water creases, impurities in the cooling water adhere to a heat exchanger tube, where they may cause corrosion.

Deposit Attack, Selective Attack, Pitting

A metal with adhered foreign objects will increase its temperature and temperature difference from other areas producing a battery effect. This symptom may cause corrosion. The adherence of foreign objects may cause deposit attack, selective attachment, and pitting of metal plates

Heating Control

For the control heating operation, adopting a thermoelectric heater SSC or SCR (optional) allows high precision control.