Introduction of Portal Crane Automation

The automation retrofitting of portal cranes is a systematic project that requires favorable conditions to be in place across multiple dimensions. These include the equipment itself, operational working conditions and personnel management. This ensures the automation system operates stably and efficiently, and that operations are safe. The following outlines the key preconditions for automation implementation from core perspectives.

1. Basic Conditions for the Portal Cranes

The portal cranes serve as the execution carrier for the automation system, and their mechanical performance, control accuracy, and operational stability directly affect the feasibility and effectiveness of the automation process. Therefore, inspection and optimization upgrades must be carried out in advance.

1.1  Verification of Mechanical System Integrity

Core Mechanism Performance Compliance: The four core mechanisms (hoisting, luffing, slewing, and traveling) must be free from structural defects, and have sensitive braking systems that provide sufficient braking torque to prevent safety hazards such as mechanism brake failure during automated operation.

1.2  Electrical Control System Requirements

The local PLC of the portal cranes must be equipped with an Ethernet communication interface that meets the communication protocol requirements of the automation PLC. To achieve step-less speed regulation and precise positioning, each actuator should be driven by a VFD, meeting the speed adjustment requirements of "light-load fast and heavy-load stable" during automated operations.

1.3  Mechanical and Communication Modification Requirements for the Portal Cranes

In order to facilitate communication between the portal cranes and the central control room, the onboard cables of the portal cranes must be equipped with at least 12 single-mode optical fibers, and the cable reel system must be fitted with 12 single-mode optical fiber couplers.

To facilitate communication for video and control signals between the upper and lower parts of the portal cranes, the central collector must be fitted with at least two gigabit Ethernet slip rings for the automation system.

To enable remote control, the slewing brake should be a frequency-conversion variable-force brake that is normally closed and has power-off and fault self-locking brake protection functions. During automated operations, automatic braking occurs in the event of a power failure or when the slewing motor stops running. The VFD of the slewing mechanism does not need to maintain torque output in this case, thereby enhancing safety and reliability.

1.4  Applicable Working Conditions and Requirements

This solution is applicable to four-bar linkage portal cranes with buckets, as well as multifunctional portal cranes with grab buckets. These cranes can be used to unload dry bulk cargo from material hoppers or the ground, or to load dry bulk cargo onto ships by grabbing materials from the ground. It is suitable for various dry bulk materials, such as coal, ores and grains, but not materials with extremely poor fluidity.

2. Central Control and Ground Infrastructure Requirements

The central control room must provide installation space and power supply for remote control consoles and server cabinets. For each portal crane, at least 12-core single-mode optical fibers must be laid from the ground junction box to the central control room for remote control automation communication.

3. Requirements for Operators and Maintenance Personnel

Implementing an automation system involves technological upgrades and requires the support of professional technical personnel to ensure efficient maintenance of the system and standardised operations.

Operator training: Operators should receive training in automated operating procedures, enabling them to master the methods of starting, monitoring and manually intervening in the automation system, as well as emergency response capabilities (e.g. shutdown operations and manual takeover procedures in the event of sudden failures).

Maintenance personnel training: Develop professional maintenance personnel with knowledge of multiple fields, including automated control systems. This will enable them to understand how the automation system works, perform routine inspections, and troubleshoot and repair common faults.