Thread Content
As the requirements for operating conditions become increasingly stringent, older temperature control devices can no longer meet the needs of modern industrial production. Modern industry must make full use of intelligent temperature control technologies with high precision and a high degree of automation in order to automate the temperature control process during heat treatment; it is therefore essential to replace traditional instruments with such advanced systems. New types of temperature control instruments have broad development prospects. For many years, traditional temperature control equipment has commonly used moving-coil millivoltmeters and electronic potentiometers as temperature control instruments, combined with AC contactors. Although their cost is low, they all suffer from poor temperature control accuracy and high power consumption. Traditional instruments have low temperature control accuracy; the temperature control deviation can be as much as ±10°C or more, making it difficult to meet the temperature requirements specified in the manufacturing processes for components. The furnace temperature can only be controlled in a gradient manner; the heating elements operate at full voltage and full power whenever they are powered on, which leads to increased abnormal power consumption by the electric furnace, results in waste of electrical energy, and indirectly raises the production costs for enterprises. New types of temperature control instruments hold broad prospects for development in the future. The traditional instruments that are currently in use typically use pointers to indicate temperature; their display is not intuitive, their accuracy is low, and they have poor shock resistance. Additionally, they require regular calibration and maintenance, which incurs high costs. The circular chart automatic balance record regulator is very troublesome to replace the recording paper on a daily basis; it is not suitable for continuous process recording over 24 hours, and the records are also difficult to preserve. Issues such as not meeting requirements affect product quality. At the same time, traditional instruments lack functions such as time-programmed control and over-temperature alarms, and thus cannot meet the requirements of processes that need temperature increase, maintenance at a certain temperature, temperature decrease at a specific rate, or execution according to other programmed sequences. Therefore, the old temperature control devices can no longer meet the demands of modern industrial production. Modern industry needs to make full use of intelligent temperature control technologies with high precision and a high degree of automation in order to automate the temperature control process during heat treatment; it is thus essential to replace traditional instruments. Currently, the MZK type intelligent temperature control cabinet is a new generation of product designed and manufactured using AI or LU series artificial intelligence industrial regulators as its core technology. It consists of smart meters, power measurement instruments, a temperature control unit using thyristors or large solid-state relays, an AC contactor power supply unit, sensors, switches, and other components. The MZK series of products features a simple circuit design and modular structure, making them very convenient for use, maintenance, and functional expansion. The industrial control software used is the high-quality domestic full-Chinese configuration software MCGS General Edition, which serves as the development platform. It runs on Chinese Windows operating systems and is capable of supporting most of the data acquisition boards, smart instruments, PLCs, frequency converters, and other hardware available on the market, offering powerful functionality. The overall structure of the continuous drying furnace system is as shown; it is the overall structure of the KCS-type computer distributed control system for continuous drying furnaces, designed in accordance with process requirements. The entire system consists of 6 furnace front control cabinets and 1 upper-level cabinet. The host computer can be a cheap ordinary personal PC; if the operating environment is poor, an industrial PC is recommended, although it is more expensive. The number of control zones is set at 24 points; it can be increased to several hundred points if more heating control zones or devices are added. The AI series of instruments for system communication use RS485 communication interfaces, with a communication distance of up to 1 km; an RS232/RS485 converter is used to connect them to the host computer. The communication interface uses 8-bit data, 1 or 2 stop bits, and no parity bits. The data uses a 16-bit checksum, whose error-correction capability is tens of thousands of times higher than that of parity checking, ensuring the accuracy and reliability of communication data. High-precision smart instruments can fully replace the functions of existing conventional instruments; more importantly, they are capable of mimicking human brain thinking to carry out tasks that traditional technologies cannot handle, in a fast and accurate manner. Based on the use of MZK-type high-precision intelligent temperature controllers and PLCs as the lower-level devices, by selecting appropriate interfaces and wiring, along with purchasing the upper-level computer and related peripherals, a KCS-type distributed control system can be established using industrial control configuration software. This type of system makes use of the sophisticated functions of upper-level industrial control software, and combines them effectively and reliably with advanced intelligent instruments and programmable controllers as lower-level components, thereby achieving automatic control of the heating furnace. As a result, the equipment features a high level of technical sophistication and processing capability. The system boasts excellent performance and reliability, low costs, and is easy to install and use, which gives it great potential for widespread adoption.