Application of industrial chillers in granulator and extrusion machinery

Application of industrial chillers in granulator and extrusion machinery

People who are familiar with the plastics industry must be familiar with pelletizers (also known as pelletizers), wire or pipe extrusion equipment. In addition to the use of temperature control equipment such as mold temperature machines in injection molding equipment, plastic extrusion equipment is also often used. Industrial chillers for extruders will be used, especially for high-speed production lines that have strict requirements on product quality or output. In the following, we will describe the problems that should be paid attention to when the cooling unit of the extrusion equipment is matched with the cooling demand characteristics of the granulator or pipe extrusion production line.

Selection of temperature control range of chiller for extrusion equipment

Usually this type of extrusion equipment does not have high requirements for temperature control, the temperature control range is generally 10 ~ 25 °C, and the temperature control accuracy of ±1 °C of general industrial chillers can also fully meet its temperature control requirements; some infrastructure uses For the production of engineering pipes and corrugated pipes, because the production requirements are not high, the cooling water can be kept at 30-50 °C, so there is no need to use a chiller, just use a cooling water tower or a cooling pool to cool the circulating water.

Selection of Extrusion Equipment Chiller Evaporator

Generally, the extrusion equipment itself is equipped with an open water tank, such as the refrigeration of the plastic granulator, the plastic particles are directly cut into a large water tank, and the extrusion of some pipes is additionally equipped with a hydraulic module, and the pump in the hydraulic module Pu transports the cooling water to the traction tank. At this time, when we choose the evaporator matching the chiller, we should choose the shell-and-tube evaporator instead of the coil-type evaporator. This is because the water tank to be cooled is an open container. When the unit stops running, the water pump will no longer work. At this time, the pump does not generate pressure, and if the liquid level of the water tank is higher than that of the chiller, the water in the cooled water tank will flow back to the evaporator of the chiller. If the water tank + coil type evaporator is used, the water It will overflow the evaporator water tank; while the shell and tube evaporator is selected, because its pipeline is closed, there will be no overflow problem.

Selection of cooling capacity of extruder chiller

Usually, we can start from the following data, and then combine the actual situation to calculate the required cooling capacity, so as to facilitate the selection of chiller for extrusion equipment:

- the size of the extruder (i.e. the amount of extrusion per hour)

- The material of the extruded material (queries the specific heat of the material)

- The temperature at which the material is extruded

- Control temperature of cooling water (combined with the initial temperature when the material is extruded, calculate the temperature difference of material cooling)

- the size or volume of the sink