Crane Extension Device Bidirectional Tension Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing crane systems can only provide unidirectional cable tension, limiting their ability to stabilize loads during offshore operations like wind turbine installation, especially under increasing wind speeds, which complicates the control system and reduces installation accuracy and reliability.
Innovation Solution
A crane extension and installation device with a pulley and winch system that allows for bidirectional tension control by using multiple pulleys and winches positioned strategically along a slide rail and cantilever beams, enabling the adjustment of cable tension direction and magnitude through the movement of pulleys and joints.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If unidirectional cable tension control is used in traditional crane systems, then the system structure is simple, but the ability to stabilize loads during offshore operations is limited and installation accuracy deteriorates
Solution Approach 1:
The crane system is segmented into multiple independent tension control units, each with its own winch and cable arrangement. The first tension control unit and second tension control unit operate independently to control different aspects of load positioning, allowing complex bidirectional tension control to be achieved through coordinated operation of simpler modular units
Solution Approach 2:
A cable redirection device (pulley system) is introduced as an intermediary mechanism between the winches and the load. This intermediary allows the tension forces from multiple winches to be combined and redirected to achieve bidirectional tension control without requiring direct mechanical connection between all components
2Reliability
If multiple winches and pulleys are added to achieve bidirectional tension control, then load stabilization capability improves, but the control system complexity increases
Solution Approach 1:
The winches and pulleys are designed to serve multiple functions simultaneously. The same cable system used for lifting also provides lateral stabilization, and the tension control units can operate in different modes (lifting, positioning, stabilizing) without requiring separate dedicated mechanisms for each function
Solution Approach 2:
The system incorporates feedback control where the tension forces generated by each winch are monitored and adjusted based on the actual load position and stabilization requirements. This feedback mechanism allows the complex multi-winch system to be controlled efficiently by continuously adapting tension forces to maintain optimal load stabilization
3Adaptability or versatility
If cables are fixed to provide only tension forces pointed to the crane, then the cable system is simple, but the ability to provide resultant forces opposite to the crane is lost
Solution Approach 1:
The cable system is extended from a single-dimension vertical arrangement to a multi-dimensional spatial configuration. By positioning winches and pulleys at different locations and angles, the system can generate tension forces in multiple directions (vertical, horizontal, and at intermediate angles), enabling bidirectional and multi-directional load control
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enhances offshore hoisting accuracy and reduces the impact of environmental factors like wind speed, improving installation efficiency and success rates by providing bidirectional tension input and precise control over load positioning.
Implementation Method 1
a fixed pulley is installed on a lower peripheral surface of the extension device... the cable bypasses the first pulley, the fixed pulley, and the second pulley with a highest vertical position to connect to a third winch
Implementation Method 2
Active feedback control can greatly improve the installation accuracy. However, only positive tension can be provided when the cable is stretched
Data Source
AI summary
A crane extension and installation device includes an extension device, a winch, a pulley and a cable. A main arm includes a vertical slide rail, the main arm is inclined relative to vertical, and three second pulleys at different heights of the slide rail are installed in the vertical direction of the slide rail, and the second pulley can slide vertically along the slide rail and can be fixed at a certain position of the slide rail. The extension device includes a number of cantilever beams connected end to end. The front end of the extension device is a cantilever beam, and a fixed pulley is installed on the lower peripheral surface of the extension device. The end face of the cantilever beam is equipped with a vertical lower arm through a joint, and the bottom end of the lower arm has a first pulley fixed by the joint.