Application scope: HCD This series of European-style dehumidifying, drying, and two-stage feeding combination units integrates three functions—dehumidification, drying, and two-stage feeding—into a single machine, also known as the “three-in-one” unit. It is particularly well-suited for engineering plastic raw materials with high hygroscopicity, such as: PA 、 PC 、 PBT 、 PET Moreover, the dew point of the accompanying rotary dehumidifier can reach below -40℃.

Features:
● Integrates three functions in one: dehumidification, drying, and two-stage feeding;
● HCD The European-style dehumidification, drying, and feeding combination is uniformly equipped with a honeycomb rotor, ensuring stable low-dew-point drying.

Dry air;
● The stainless steel insulated drying hopper features a downward-blowing air duct design, ensuring uniform drying of the raw materials and effectively preventing heat loss.

● The feeding system is equipped with a cut-off valve to ensure that no residual material remains in the material tube.

● A closed-loop feeding system that prevents raw materials from being contaminated or re-humidified;

● Optional PLC control with an LCD touch-screen HMI is available, offering centralized and convenient operation and enabling the entire machine to run automatically.

● Optional dew-point detection device available.

Working principle:

Drying and Dehumidification Section: The moist, warm air returning from the drying hopper is cooled and then blown into the honeycomb rotor. The moisture in the air is adsorbed by the rotor and subsequently desorbed by a regeneration heated air stream. These two air streams act on the rotor simultaneously, and as the rotor rotates, moisture in the air is continuously adsorbed and then desorbed by the regeneration air before being discharged. This process produces stable low-dew-point air, which is heated to the drying temperature required for plastics and then blown into the drying hopper, creating a closed-loop system that dries the raw materials.
 

Material-suction section: Material suction involves drawing dry material from a storage bin or other storage container into the drying hopper. When the microswitch in the vacuum hopper detects that there is no more material, the suction motor starts running, creating a vacuum inside the vacuum hopper. Due to the pressure difference between the air inside the storage bin and the vacuum hopper, the raw material is drawn into the vacuum hopper. Once the suction period is complete, the suction motor stops operating.

The raw materials fall into the drying hopper under their own weight. After being dried, the raw materials are pumped from the drying hopper to the equipment installed for plastic molding.

In the machine's photoelectric hopper or other hoppers.

Relative Humidity and Dew Point:
Relative humidity: Relative humidity is the percentage of the actual water vapor density in the air compared to the saturation water vapor density at the same temperature.

Dew point: refers to the temperature at which saturated water vapor in the air condenses and forms dew. 100% When the relative humidity is at its maximum, the temperature of the surrounding environment is the dew point temperature. The lower the dew point temperature is compared to the ambient temperature, the less likely condensation is to occur—meaning the air is drier. The dew point is unaffected by temperature but is influenced by pressure. 。

Why use a three-in-one dryer:

Bubbles, silver streaks, cracks, flow marks, and poor transparency—these defects are primarily caused by insufficient drying of the plastic before molding. Engineering plastics such as: PA 、 PC 、 PBT 、 PET 、 NYLON For raw materials with strong hygroscopic properties, since moisture penetrates deep into the plastic pellets, conventional dryers cannot completely dry them. Practical experience has shown that lowering the dew point of the drying air to... -40 Below ℃, while simultaneously controlling the heat to ensure it blows over the surface of the moisture-containing plastic pellets, the moisture content can be reduced to before molding. 0.02% Next, the dehumidifying and drying feeding combination works by thoroughly dehumidifying and heating air within a closed-loop system. The dried air rapidly and completely removes moisture from the plastic pellets, achieving the desired dehumidifying and drying effect.
 

Application example:

Model Specifications

Note: 1. When selecting a dew point detection device, add “D” after the model number.
2. When selecting a PLC controller paired with an LCD touch-screen human-machine interface, add the letter “P” to the end of the model number. Please note that product specifications are subject to change without prior notice.
3. The machine’s voltage specifications are: 3®, 380V AC, 50Hz.