Temperature control method of temperature control system of plastic drying machine

Abstract

The invention discloses a temperature control method for a temperature control system of a plastic drying machine, which comprises the following steps of: setting a plurality of setting periods with the same duration, setting different counting thresholds in different setting periods, and setting corresponding temperature setting values for controlling drying temperature according to different counting thresholds. The counting is used for recording the number of times of material pumping of a stock bin of the plastic feeding equipment, and when the counting value in the working period reaches a counting threshold value of a certain set period, a temperature value preset in the set period is sent out to control the drying temperature of the drying machine. The quantity of raw materials is confirmed by recording the material pumping times of the stock bin of the plastic feeding equipment, meanwhile, the corresponding drying temperature value and the triggering threshold value are set according to the drying data of the plastic drying machine, and the corresponding temperature values for controlling the drying machine are sent by triggering different counting threshold values. Therefore, the energy consumption can be reduced while the drying quality of the plastic raw materials of the plastic dryer is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of temperature control systems, in particular to a temperature control system for a plastic dryer. Background Art

[0002] In the plastic molding process, plastic dryers as auxiliary equipment are crucial to product quality. According to molding requirements, different types of dryers can be selected, such as ordinary hot air dryers, vacuum dehumidification dryers, and honeycomb rotary dehumidification dryers. The core mechanism of these devices is to heat the gas and send it into the drying chamber through wind flow to evaporate the moisture in the plastic raw materials. Ordinary hot air dryers directly discharge the hot and humid gas outdoors, while vacuum dehumidifiers and honeycomb rotary dehumidifiers use a recovery system to dehumidify the hot and humid gas and convert it into regenerated air with low moisture content for reuse, thereby improving drying efficiency and quality.

[0003] However, in the plastic molding process, the amount of raw materials used varies depending on the product specifications of the workpiece, the output, and the dryer needs to serve multiple molding equipment. When the amount of raw materials used is small, it is easy to cause the raw materials to turn yellow, discolor and stick due to over-drying, resulting in the scrapping of the raw materials. The traditional response method is: the operator manually adjusts the drying temperature according to the amount of raw materials used based on work experience.

[0004] However, this operation mode has significant defects: when the amount of raw materials fluctuates greatly, it is difficult to adjust to the appropriate temperature in time. As a result, when the amount of raw materials is small, they are easily scrapped due to over-drying, and when the amount is large, the moisture content is too high due to insufficient temperature, and production needs to be stopped to wait for drying. This not only affects the stability of product quality, but also causes waste of electricity and even causes direct and indirect economic losses. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for adjusting the drying temperature of a plastic dryer according to the amount of raw materials used.

[0006] The technical solution adopted to solve the above technical problems is: a temperature control method for a temperature control system of a plastic dryer, characterized in that: a number of set cycles are set with the same duration, different counting thresholds are set for different set cycles, and corresponding temperature setting values ​​for controlling the drying temperature are set according to different counting thresholds. The counting is to record the number of times the plastic feeding equipment draws material from the silo. When the count value within the working cycle reaches the counting threshold of a certain set cycle, a temperature value preset for the set cycle is issued to control the drying temperature of the dryer.

[0007] On the basis of the above, the counting is to record the number of times the silo is switched on and off to start pumping materials or the number of times the vacuum is switched on and off in the vacuum pipeline.

[0008] The beneficial effects brought by the use of the present invention are as follows: the present invention confirms the amount of raw materials by recording the number of times the plastic feeding equipment draws materials from the silo, and sets the corresponding drying temperature value and trigger threshold value according to the drying data of the plastic dryer, and sends the corresponding temperature value for controlling the dryer by triggering different counting threshold values. Therefore, the present invention can ensure the drying quality of the plastic raw materials of the plastic dryer, while avoiding the waste of electric energy and the scrapping of raw materials due to abnormal drying, which can effectively reduce economic losses and improve production efficiency and product quality stability. DETAILED DESCRIPTION

[0009] Usually, the temperature control system of the plastic dryer manually sets the drying temperature based on the amount of raw materials used based on experience, and controls the temperature control system through the set temperature to provide a suitable drying temperature. Moreover, the amount of material drawn from the silo of the plastic dryer each time is consistent, and the amount of raw materials used is reflected in the frequency of drawing materials. In the present invention, the temperature control method of the temperature control system is: setting a number of set cycles with the same duration, setting different counting thresholds for different set cycles, and setting corresponding temperature setting values ​​for controlling the drying temperature according to different counting thresholds. The counting is to record the number of times the silo of the plastic feeding equipment draws material. When the count value within the working cycle reaches the count threshold of a certain set cycle, a temperature value preset for the set cycle is issued to control the drying temperature of the dryer.

[0010] The counting is to record the number of times the silo is switched on and off to start pumping materials or the number of times the vacuum is switched on and off in the vacuum pipeline.

[0011] Assume that a plastic processing plant uses this method to dry PET raw materials. According to production requirements, the user uses a chip control system and a counting unit, sets 4 set cycles, the cycle duration is 60 minutes, and the counting thresholds in each set cycle are set to 30 times, 40 times, 50 times, and 60 times respectively. At the same time, the corresponding temperature setting values ​​are set to 130℃, 140℃, 150℃, and 160℃ respectively.

[0012] In the actual production process, when the counting unit counts 30 times in the working cycle from 8:00 to 9:00 in the morning, the chip control system sends the corresponding temperature setting value of 130°C to the temperature control system of the plastic dryer, and maintains the drying temperature of the temperature control system at 130°C. Similarly, when the working cycle from 9:00 to 10:00 reaches 50 times, the chip control system sends the corresponding temperature setting value of 150°C to the temperature control system, and adjusts the drying temperature of the temperature control system to 150°C. In this way, it is ensured that the PET raw materials can be properly dried at any dosage, thereby improving the drying quality and product stability.

Claims

1. A temperature control method for a temperature control system of a plastic dryer, characterized in that: Several setting cycles are set with the same duration, and different counting thresholds are set for different setting cycles. At the same time, corresponding temperature setting values ​​for controlling the drying temperature are set according to different counting thresholds. The counting is to record the number of times the plastic feeding equipment draws materials from the silo. When the counting value within the working cycle reaches the counting threshold of a certain setting cycle, the temperature setting value preset for the setting cycle is issued to control the drying temperature of the dryer.

2. The temperature control method of the temperature control system of the plastic dryer according to claim 1, characterized in that: The counting is to record the number of times the silo is switched on and off to start pumping materials or the number of times the vacuum is switched on and off in the vacuum pipeline.