SCIENCE COMMUNITY: WEB OF CONFERENCES
October-December, 2021
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(3-5 mm). An increase in the volumetric weight in the scattered state increases the productivity of the
production of a granule-making aggregate.
The granulation process consists of the following: the polymer in the powder state or PKM is put in
a cylinder, under the influence of a certain temperature the material passes into a flowing state, the
mass with the help of a cord is continuously squeezed out in the form of a ribbon or wire, cooled and
cut into granules. Such aggregates are referred to as granulators.
Taking Pills
Thermo-reactive composition materials are often in a crumbly state. Their use in this case is rather
inconvenient. Therefore, they are brought to a state of pre-condensation. This process also applies to
fluoroplastics.
Pills it is performed on special hydraulic (automated) presses. Press-powder at room temperature
turns into a mass of a certain size and shape, free from Air, crispy. From the fiber press materials it is
possible to obtain a net with a known (rope) shape through a cord aggregate.
Preheating polymer materials
This thermo reactive materials by pressing the product is obtained and vacuum and pneumatic
formation; Welding is carried out at a high temperature. Preliminary heating is important in the
technology of processing plastic. Initial heating also reduces the destruction, pressing time under the
influence of high temperature when taking parts.
For example, when taking an item from list materials, if the material is not heated evenly, the
degree of orientation of the macromolecules will be different on account of the residual voltage, as a
result of which microdarkets and distortion will occur in the items. The process of fastening, since the
thermal conductivity of polymer materials is low it becomes more difficult. When pressing the, only
the surface of the material warms up. The initial heating process reduces the primary pressings
(prepressing) and pressing time, so that bubbles do not form on the surface of the piece. The initial
heating process can be carried out in building cabinets or high-frequency devices and infrared heat
sinks.
Polymer materials with high dielectric properties are heated in building cabinets. It is also desirable
to heat the clear lists in the construction cabinets, because infrared heating is more effective.
When the Material is heated by high-frequency currents, it is placed between the condenser plates.
Pill the material in the form of a net is placed in a condenser connected to the Earth (ground
connection). When the plates are connected to a high-frequency current generator, a voltage elector
field is generated between the plates:
here: U-the given voltage -, V; H-the distance between the plates, m.
High-frequency spill heating of materials depends on their structure. Polarized polymers (PE, PS,
fluoroplasts) are not heated in a high-frequency electric field. Therefore, they are used as
highfrequency current insulators. Polarized polymers (PVC, FFS) are very quickly heated in the
electric field. The tendency of polymers to heat up on a high-frequency current can be determined by
the dielectric loss value equal to the yield of the plug tgb ( TGB-dielectric absorption). The larger the
yield, the more electricity is converted into heat energy.
When we use the full power of high-frequency devices, the heating time of thermo reactive
materials is usually 20-30 SEC. The temperature of the material heated in the this is 120— 130°C.
This reduces the fastening time of the reagoplasts by 20-30%, and the number of primary pressing
decreases, resulting in a decrease in the feed of the press and press uniform.
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