The plastics processing sector comprises all those industries responsible for processing and shaping plastic materials.Injection molding and the extrusion process are among the most common water-intensive processes used for this purpose.
INJECTION MOLDING
Injection molding consists of introducing the molten plastic material into a mold, where, through cooling, solidification and subsequent separation of the plastic is achieved
EXTRUSION PROCESS
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The extrusion process melts the plastic and pushes it into a Nozzle giving it the desired shape. As it leaves the Nozzle, it is introduced into a bath to cool and solidify
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COOLING OF EXTRUSION AND INJECTION PROCESSES
Commonly, both the cooling of the injection molds and the plastic obtained by extrusion is carried out with cold water (<16). In addition, there is also water consumption associated with extruder cooling and hydraulic systems. After being used for cooling, the hot water has to be cooled in order to carry out itsreuse in the processthe hot process water is pumped to a tank from where it is pumped to one or more cooling units to be cooled and returned to the tank, and since cold water and hot process water with suspended and/or dissolved solids are continuously entering the tank, it is necessary to protect both the extrusion and injection equipment and the cooling systems.
Since cold water and hot process water with suspended and/or dissolved solids are continuously entering the tank, it is necessary to protect both the extrusion and injection equipment itself and the cooling systems. For example, since the water from the extrusion baths brings particles from the environment and traces of plastic into the tank, it is necessary to carry out filtration prior to the cooling systems. By protecting them, we can increase their efficiency, reduce downtime for cleaning, and achieve better cooling of the extrusion process
For Injection processes, it will be necessary to use filtration to ensure that the cooling water does not cause deposits in the cooling channels of the molds. In addition, it is essential to have a filtration system to ensure that the water used in the cooling of the hydraulic systems is free of suspended solids. In this way, we will avoid the obstruction of the plates, Driplines or housings of the heat exchangers, thus improving the heat transfer between the water and the hydraulic fluid
IMPORTANCE OF SOLIDS-FREE WATER IN THE EXTRUSION AND INJECTION PROCESS
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Water free of solids is capable of absorbing the same amount of heat more quickly than water containing solids, since their presence increases the resistance to heat transfer. Therefore, the condition of the water is essential to achieve adequate cooling to achieve higher productivity, obtain quality parts and increase the service life of the equipment.
WEIR SOLUTIONS
Since water quality plays a crucial role in the efficiency of cooling, it is essential to perform a proper treatment on it. For this reason, AZUD offers solutions with several configurationsTo protect cooling systems as well as extrusion and injection equipmentaZUD HELIX AUTOMATIC AA units with disc filtration guarantee the removal of a wide range of sizes of organic particles coming from the water-mold contact, as well as particles coming from the extrusion baths. Requiring low pressures to carry out the filtration, the AA units can be implemented to protect the equipment either in full flow (1) or in sidestream (2)
Configuration 3, which allows continuous cleaning of the tank, can also be chosen
