chiller

1、 Core functions and importance

Rapid cooling and shaping (core function): Quickly cool the high-temperature melt (200-300 ℃) coming out of the extruder die to room temperature (10-25 ℃) at the moment of cutting or in a water tank, so that the plastic solidifies from the molten state into particles and prevents adhesion and deformation.

Accurate control of water temperature: Based on the characteristics of different plastics (such as PVC requiring rapid cooling and PE/PP requiring slow cooling), the cooling water temperature is precisely controlled within ± 1 ℃ to meet the cooling process requirements of different materials.

Recycling and water conservation: Recycling cooling water can save over 95% of water compared to direct discharge tap water cooling, which meets the requirements of environmental protection and sustainable development.

Stable product quality: Constant water temperature ensures consistent particle crystallinity, uniform internal stress, and no bubbles or pores in appearance, significantly improving the quality of the finished product.

Improve production efficiency: Adequate cooling capacity can support continuous and stable operation of high-speed granulation lines, without causing particle adhesion or downtime due to high water temperature.

2、 Working principle

The chiller operates based on the principle of vapor compression refrigeration cycle:

Refrigeration cycle: The compressor compresses the gaseous refrigerant into a high-temperature and high-pressure gas, which then enters the condenser and is cooled by air (air-cooled) or cooling water (water-cooled) to become a high-pressure liquid. The refrigerant is then depressurized by a throttle valve/expansion valve to become a low-temperature and low-pressure liquid refrigerant. It then enters the evaporator, absorbs heat, vaporizes, and returns to the compressor to complete the cycle.

Water cycle: The hot water in the granulation water tank is sent to the evaporator through a circulating water pump, where it exchanges heat with the low-temperature refrigerant. The heat is absorbed by the refrigerant, and the water temperature decreases. The cooled chilled water is then sent back to the granulation water tank for recycling.

Automatic temperature control: The temperature sensor monitors the water temperature in real time, and the controller automatically adjusts the start/stop/operation frequency of the compressor and fan through PID calculation to stabilize the water temperature at the set value.

4、 Core structure composition

Refrigeration compressor: the "heart" of a chiller. We often use fully enclosed scroll or piston compressors (such as brands from Japan Sanyo, the United States Gulun, France Baifuma, etc.), which have low noise, high efficiency and energy saving, and good sealing performance.

Condenser:

Air cooled: high-efficiency finned condenser+low-noise axial fan.

Water cooled: Shell and tube condenser, requiring an external cooling tower.

Evaporator: Core heat exchange component. It is usually recommended to use shell and tube evaporators instead of coil type chillers for granulation lines to prevent backflow and overflow problems when the water tank level is higher than the chiller.

Throttling device: Thermal expansion valve or electronic expansion valve, precisely controlling the flow of refrigerant.

Water circulation system:

Stainless steel water tank: stores chilled water, with built-in float ball automatic water replenishment device.

Circulating water pump: Stainless steel high flow and high head water pump is selected, which is quiet, durable, and leak free.

Water pipeline: SUS304 stainless steel material, corrosion-resistant, ensuring water quality.

Rack and outer cover: High strength integral welded frame, electrostatic spray coating or stainless steel outer cover, beautiful and durable.

Core features and advantages of the product

High precision constant temperature control: The temperature control accuracy can reach ± 1 ℃, meeting the strict requirements of various plastic granulation processes for water temperature.

Efficient and energy-saving: using high-efficiency compressors and heat exchangers, with high energy efficiency ratio (EER) and low long-term operating costs.

Stable and reliable: The core components are selected from internationally renowned brands, with multiple safety protections to ensure 24-hour continuous and stable operation.

Anti backflow design: In response to the open characteristics of the granulation water tank, a shell and tube evaporator is adopted to completely avoid the problem of water backflow and overflow during shutdown.

Water quality assurance: The water tank and pipeline are made of stainless steel to prevent corrosion, ensure clean cooling water, and avoid contaminating particles.