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Keywords: Kneader, constant temperature water supply system, humanoid intelligent control. Authors: Yi Pengxing, Du Runsheng. Corresponding address: Department of Mechatronic Information Engineering, School of Mechanical Engineering, Huazhong University of Science and Technology, 430074. Phone: (027) 87542079-4. Introduction: Large vertical kneaders are key equipment for the production of solid propellants in a certain chemical plant, and they are also essential for ensuring safe and reliable production. During the kneading process, due to the friction between the impellers and the material as well as the chemical reactions of the material, the reaction temperature of the mixed material can rise or fall sharply, which has a direct impact on the safety of the mixing process and the quality of the product. To maintain a certain temperature of the material during the reaction process and ensure optimal production conditions, it is necessary to control the reaction temperature. This equipment uses a jacket for heat transfer; the jacket is filled with insulating material, and it contains multiple layers of heating (cooling) water pipes. The reaction temperature of the materials in the mixing tank is adjusted by circulating water at a certain temperature being fed into the water pipes. Controlling the temperature of the material being mixed actually means controlling the temperature of the circulating water in the jacket; therefore, establishing a practical and reliable water supply system is a fundamental requirement for ensuring the proper operation of the mixing equipment. The original water supply system of the kneading equipment used a medium-temperature water tank and a low-temperature water tank in alternation to circulate water through the jacket of the kneading pot, thereby controlling the temperature of the circulating water in the jacket pipes and achieving control over the reaction temperature of the mixed materials. This water supply system has shown problems such as high water loss and low precision in temperature control during use. 1 Water supply system pipeline design: The control tank in the system is primarily used for regulating the temperature of the mixing pot ； Electric boilers are used to heat the system’s circulating water ； The soft water tank has two functions: on one hand, it ensures that the water level in the control tank remains above the normal operating level; on the other hand, it helps to cool down the control tank. 1.1 Composition of the system circuit 1.2 Installation characteristics of the system 2 Implementation of control for the constant-temperature water supply system 2.1 System data acquisition To enable effective monitoring at the site, level gauges and thermometers are installed in each water tank to collect data on the level and temperature of the water within those tanks. Temperature sensors are placed at the outlet and inlet of the kneading tank to measure the temperature of the circulating water, and the temperature of the kneading tank is also detected by temperature sensors. 2.2 Humanoid intelligent temperature control algorithm: Due to the numerous temperature-related disturbances and complex variations during the kneading production process, it is difficult to establish an accurate mathematical model of temperature changes; conventional control methods struggle to achieve satisfactory control results. In the past, during the control of the kneading temperature for similar equipment, operators would use the data displayed on monitors or alarm signals to manually operate buttons in order to send commands via the PLC to control the solenoid valves and thus adjust the temperature of the circulating water. The safety of production and the quality of kneading depended to a large extent on the operator’s experience, resulting in imprecise control and significant potential risks. 2.3 System Monitoring Implementation: Based on the working process and characteristics of the kneading equipment, and in order to increase the degree of automation while making full use of existing resources, the constant-temperature water supply system for the mixing vessel is monitored within the hardware and software environment of the mixer’s HMI-IPC control system. 3 Conclusion: There are numerous temperature control requirements in chemical production processes. When designing corresponding temperature control systems, it is essential to take into full account the application scope of the system, the operating environment, the control methods, and the required control accuracy, in order to ensure that the designed system meets the needs of actual production. The constant-temperature water supply system introduced in this article is quite versatile, featuring a high degree of automation and precise control, making it suitable for general kneading and mixing production processes as well as similar manufacturing processes with specific requirements.