SU428955A1 - METHOD OF AUTOMATIC CONTROL OF THE DRYING PROCESS OF POLYMERIC MATERIALS - Google Patents

Description

one

This invention relates to methods for automatically controlling processes in screw machines, for example, during the drying of polymeric materials.

Methods are known for automatically controlling the drying process of polymeric materials in a worm machine by adjusting the temperature of the material on the machine's output, affecting the frequency of rotation of the worm shaft. However, the known methods do not allow to obtain a material of a certain moisture content and do not provide the quality of the material drying process.

The aim of the invention is to provide the desired moisture content of the material and improve the quality of the drying process.

To achieve this goal, it is proposed to measure the frequency of the vras, of the worm shaft and adjust the temperature according to the functional dependence of the measured parameter.

The drawing shows a schematic diagram of the control of the process of drying polymeric materials in a screw machine.

Worm machine 1 has a feed hopper 2, a drain device 3, a discharging device 4, a device 5 for removing steam and an outlet b

The control system for the drying of polymeric materials includes a temperature sensor 7, a temperature meter 8, a regulator 9, an operating mechanism 10, a frequency changing device 11, a frequency measuring sensor 12 and a corrector, its device 13.

A polymeric material is fed into the hopper 2 of the worm machine 1, which

as it progresses, it is vigorously stirred and heated, with this: a significant part of the moisture is removed through the drain device 3. The remaining part of the moisture is under pressure, at which the heated material

is in machine 1, remains in a liquid state. After the material leaves the machine through the device 4, the moisture is instantly evaporated from the material and is removed through the device 5, and the dry material is directed to

further processing through the hole 6.

When the machine is running, the temperature sensor 7 with the aid of the meter 8 sends signals to the input of the proportional-integral controller 9, the output of which acts on the actuator 10 of the device 11 for changing the frequency of rotation of the worm shaft. The signal is proportional to the frequency of rotation of the shaft, measured by the sensor 12, is fed to the input of the correction device

13, the output of which affects the change of the setpoint to the temperature controller 9.

When the material supply to the machine is changed, the temperature deviates from the setpoint. The regulator 9, striving to maintain the temperature setpoint, will change the frequency of rotation of the shaft, driving it in accordance with the performance of the machine. The corrective device 13 will change the reference to the controller 9 in accordance with the received dependence and will change the shaft rotation frequency, setting the machine performance to the specified program.

Subject invention

A method of automatically controlling the drying process of polymeric materials in a worm machine by controlling the temperature of the material at the machine’s output with an impact on the speed of rotation of the worm shaft, characterized in that, in order to ensure the specified moisture of the material

and improving the quality of the drying process, measure the speed of rotation of the worm shaft and adjust the temperature according to the functional dependence of the measured parameter.