According to GB/T 151 and the general industry method for checking heat exchange area, the actual heat exchange margin of a hot and cold heat exchanger should typically be between 10% and 20% of the design load. If the margin is too small, the outlet temperature is prone to fluctuate with load changes; if the margin is too large, the control valve opening is too small under low-load conditions, and the pressure drop characteristics deteriorate. The HDX-340 hot and cold heat exchanger is designed around this verification range and is suitable for selection calculations in liquid-liquid heat exchange scenarios.
Temperature cycling accelerates the aging of sealing materials. For operating conditions with frequent medium temperature fluctuations, it is recommended to shorten the seal replacement cycle and to confirm the correspondence between the sealing material and the upper limit of the medium temperature during selection. The HDX-340 offers material options such as nitrile rubber and fluororubber, which users can determine based on medium corrosiveness and temperature range.
Outlet temperature fluctuations and increased pressure drop on site are often related to deviations in heat exchange area verification and mismatches between materials and medium corrosiveness. It is recommended to first recheck the deviation between the design heat exchange capacity and the measured value, then inspect the heat exchange surface for scaling and the flow channels for blockage, and finally verify whether the material grade is suitable for the medium composition.
The HDX-340 is suitable for a temperature range of -20°C to 150°C. The design pressure is determined according to the user's operating conditions, and the connection specifications and plate/tube bundle materials can be selected according to medium characteristics. During selection, four basic data items must be provided: flow rate, inlet and outlet temperatures, medium composition, and allowable pressure drop.
It should be noted that the above parameters are reference ranges for selection, and the specific configuration should be based on the results of operating condition calculations.
