Forced mixers are widely adopted in commercial concrete mixing equipment due to their superior mixing quality, strong overload capacity, segregation-free discharge, high production efficiency, and adaptability to various types of concrete. However, their structure is relatively complex, and operating costs are higher. Forced mixers can be categorized into double horizontal shaft, single horizontal shaft, single vertical shaft, and planetary types.
The double horizontal shaft mixer is highly suitable for commercial concrete production owing to its excellent mixing performance, high efficiency, adaptability, distinctive structural features, and reliability. In contrast, single horizontal shaft and single vertical shaft mixers are being used less frequently in commercial concrete mixing equipment due to their structural limitations and adaptability. Planetary mixers are not yet widely adopted and are mostly found in imported equipment.
Electrical Control System for Commercial Concrete Mixing Equipment
Currently, domestic concrete batching plants employ a variety of electrical control systems, primarily the following three control modes:
Distributed Microcomputer Control: This control method was widely used in early batching plant designs. The core of the system is a programmable logic controller (PLC), while the upper-level computer is mainly used for report generation and printing, with its functionality and role being relatively limited. With the increasing application of commercial concrete, the functional requirements for batching plants have become more complex, making this control method difficult to implement effectively.
Centralized Microcomputer Control: In this mode, both control and management functions are concentrated in a single computer, resulting in a heavy workload. Additionally, real-time statistical data collection during production is not possible, and measurement accuracy is susceptible to human interference. Factors such as the design of the measurement control program, signal amplifier performance, and the precision of A/D converter cards can all affect measurement accuracy.
Centralized Dual-Microcomputer Control: This approach eliminates human interference in measurement by employing dedicated batching control instruments. It separates production control and management functions into two independent computers, ensuring no mutual interference. Production control and report generation are synchronized, and the management computer can also serve as a backup for production operations. Furthermore, this system provides a network interface for connectivity with upper-level computers.
