Screen changer is essential for the production of recycled plastics

In the plastic extrusion production, there may be a variety of impurities in the raw materials and foreign matter and plasticization of incomplete fine crystal particles, especially recycled plastic recycling process there are scraps of paper, aluminum foil, gravel, iron, copper, Failure defoamers and other impurities, the presence of these impurities if not installed for the filter for impurity filtration, will result in product quality decline, defective production and production of the interruption, and even damage to the extrusion equipment to As for the huge waste of raw materials, high production costs and energy consumption, production capacity is relatively lower, the labor intensity of workers increased.

Screen changer is essential in the production of recycled plastics equipment. Extruder does not stop for the network filter (screen changer) not only through the filter for a variety of impurities in the filter, more importantly, the installation of the screen changer can not stop the extruder to produce and remove the mold can replace the filter , A specific type of screen changer can also affect the normal production of the product under the state of the filter replacement, reducing energy consumption, waste, cost and labor intensity of workers to improve the production capacity and economic benefits.

The basic configuration of the changer consists of the main body of the changer and the hydraulic power system, and the electromechanical control system can be used to control the changing time more accurately.

The screen changer in the normal working pressure to reach the filter station to switch freely, but also to ensure that no leakage material, which on the quality and manufacturing of the network made a very high demand, only poor, unqualified for Network equipment will appear leakage material situation. And to a qualified screen changer, the first in the structural design to be reasonable, followed by the material (high-quality alloy steel) is guaranteed, once again in the processing technology and precision to be accurate, the final assembly and commissioning to have experience in order to ensure that change Network device in the high temperature, high pressure state, no deformation, and always maintain the precision with the precision, long-term leakage material.

Recycled plastic recycling production, are generally carried out recovery granulation production. Will be recycled plastic broken, washed dehydration drying, and then granulation production. Granulation unit configuration generally used feeding machine, feeding device, granulator, screen changer, granulation mold, pelletizer and other components. In the granulation process is divided into underwater stripping, water ring cut, eager and so on. Different types of granulation processes require different types of screen changers. The screen changer is divided into single-board duplex station changer, double-board duplex station changer, double column duplex station changer, net belt type automatic screen changer, are suitable for granulation production, According to different working conditions and production requirements to choose a different screen changer.

Single-plate duplex station changer, is a slide in a two filter station, a work, a spare, when the need to replace the filter, start the hydraulic device, in 1 second to achieve the station switch, the dirty Network station introduced, spare station to enter, complete the process for the network. The changer is installed in the middle of the extruder barrel and mold, with flange connection. Single-plate duplex switch netters in the changeover will cause material flow instantaneous interruption, material pressure fluctuations and the amount of extrusion reduction in the actual production of water under the performance of the production of partial stripping phenomenon, the need to re-traction Material; water ring cut and eagerly no effect, to achieve continuous production, without interruption. So the veneer duplex screen changer is more suitable for recycled plastic production in the water ring cutting and eager production.

Net belt type automatic screen changer, is the true sense of the automatic network equipment, the use of mesh belt filter, according to the material pressure automatic network, without manual network, until the filter to go through, apply to All kinds of granulation production process. Net belt type automatic screen changer basically no pressure fluctuation (can set the control range), change the network without power, relying on the pressure of the material to drive the network automatically with the network, the network process is stable and stable. The limitations of the use of water-cooled seal, take the floor to start the export heating to go to the network, there is a certain time process, requiring time intervals for more than 30 minutes to achieve automatic control of the network, the filter belt with a relatively high cost Net belt out of the waste is relatively more.

Double-column, double-plate duplex screen changer with dual-channel dual-bit design, work two filter stations at the same time work, change the network, the two filter stations alternate network, a change of network a work, always To keep the flow of the flow in order to achieve in the water under the bar to produce the effect of continuous bar, apply to the production of underwater granulation. Double-column, double-plate duplex machine for the cost of manufacturing factors, the price is relatively high, for the recovery of granulation production is not high cost, it is not widely used in the recovery granulation.

Now the recycling of granulation production applications in the network equipment due to price factors, widely used manual changer, electric screen changer and pneumatic changer, low cost, ordinary use of ordinary steel, or even without heat treatment, sealing treatment Bad, general leakage of material, and the need for downtime for network equipment, but more suitable for low-end, low production capacity of the recovery of granulation production.