Rotating Cutter Head Bits for Dredger Wear Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Cutter-suction dredgers face high wear rates and short lifetimes of excavating tools, particularly when cutting hard surface materials, leading to increased downtime and inefficiency due to the design limitations of existing cutter heads.
Innovation Solution
A cutter head design featuring a base ring and hub positioned rotationally symmetric about an axis of rotation, with arms comprising groups of adjacent bits that form straight line segments, allowing for efficient cutting and scooping, and a configuration that enables effective operation at various angles and directions, including perpendicular to the axis of rotation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional cutter heads with chisel teeth are used to cut hard surface materials, then cutting capability is achieved, but tool wear is high and tool life is short
Solution Approach 1:
The cutter head is divided into multiple independent arms that can rotate freely around their own axes. Each arm carries cutting tools and can independently adjust its orientation, allowing the system to distribute cutting forces across multiple segments rather than concentrating stress on fixed teeth, thereby reducing wear and extending tool life
Solution Approach 2:
The arms are designed to rotate freely around their longitudinal axes during operation, transforming from a static structure to a dynamic one. This rotational freedom allows the arms to self-adjust to cutting conditions, optimize contact angles with the material, and distribute wear more evenly across the cutting tools, significantly improving tool life while maintaining cutting capability
2Device complexity
If conventional cutter heads with fixed arms are used, then structural simplicity is maintained, but the cutter head cannot operate effectively at various angles and directions
Solution Approach 1:
The arms are designed to rotate freely around their longitudinal axes during operation, transforming from a static structure to a dynamic one. This rotational freedom allows the arms to self-adjust to cutting conditions, optimize contact angles with the material, and distribute wear more evenly across the cutting tools, significantly improving tool life while maintaining cutting capability
Solution Approach 2:
The cutter head design allows the same structure to effectively operate at various angles and directions perpendicular to the rotational axis. The free-rotating arms can adapt to different cutting orientations, making the cutter head universally applicable for multiple dredging operations without requiring structural modifications
3Productivity
If conventional cutter heads operate at high speeds, then productivity is improved, but vibrations increase and working conditions deteriorate
Solution Approach 1:
The arms are designed to rotate freely around their longitudinal axes during operation, transforming from a static structure to a dynamic one. This rotational freedom allows the arms to self-adjust to cutting conditions, optimize contact angles with the material, and distribute wear more evenly across the cutting tools, significantly improving tool life while maintaining cutting capability
Solution Approach 2:
The free-rotating arms act as natural vibration dampers by converting harmful vibrations into rotational motion around their axes. This passive vibration absorption reduces the transmission of vibrations to the cutter head body and vessel, improving working conditions while allowing high-speed operation for enhanced productivity
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
The design results in reduced wear, increased tool life, smoother operation, and improved working conditions by distributing cutting forces evenly and reducing vibrations, enhancing the productivity and reliability of cutter-suction dredgers.
Implementation Method 1
The bits are free to rotate about their body axes. This has the advantage that the bits are self-sharpening
Implementation Method 2
The bed material is loosened and cut by the excavating tools and is sucked into the suction opening through the space in between the arms
Implementation Method 3
In order to suck the bed material into the suction tube a wear-resistant pump may be provided, such as a centrifugal pump
Data Source
Figure 1
Figure 2
Figure 3a
AI summary
The invention relates to a cutter head (1) for removing material from a water bed. The cutter head (1) is arranged to rotate about an axis of rotation (RA). The cutter head (1) comprises a base ring (10) and a hub (20), the base ring (10) and the hub (20) being positioned rotational symmetric with respect to the axis of rotation (RA). The cutter head (1) comprises a plurality of arms (30) extending between the base ring (10) and the hub (20), the arms (30) comprising a plurality of excavating tools (40). The excavating tools are provided by bits (40) having rotational symmetric bit ends (41), wherein the arms (30) comprise one or more groups of bits (40), each group comprising three or more adjacent bits (40) of which the bit ends (41) define a straight line segment (LS).