Asymmetric Pump Impeller With Internal Cavities for Balance Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Asymmetric pump impellers used in sewage and submersible pumps face static and dynamic imbalances due to their non-rotationally symmetrical geometry, which requires manual balancing post-manufacturing, limiting hydraulic efficiency and increasing manufacturing tolerances.
Innovation Solution
The use of additive manufacturing to create pump impellers with internal cavities that shift the axis of inertia towards the axis of rotation, allowing for balanced design and production, eliminating the need for post-manufacturing balancing through the strategic placement and configuration of cavities during the manufacturing process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If manual balancing is performed by removing material, then static and dynamic imbalances are corrected, but manufacturing precision is reduced and additional processing time is required
Solution Approach 1:
The balancing cavities are designed and integrated into the impeller geometry during the additive manufacturing process itself, rather than performing balancing operations after manufacturing. This preliminary action eliminates the need for post-manufacturing material removal and achieves both high precision and reliability simultaneously
2Productivity
If additive manufacturing is used to create internal cavities, then manufacturing complexity is reduced and production efficiency is improved, but the ability to achieve precise geometric tolerances worsens
Solution Approach 1:
The invention changes the manufacturing approach from traditional subtractive methods to additive manufacturing, fundamentally altering how the impeller is produced. This parameter change enables the direct integration of balancing cavities during manufacturing, achieving both high productivity and sufficient geometric precision for balancing purposes
3Reliability
If balancing weights are added to correct imbalances, then static and dynamic imbalances are corrected, but the hydraulic efficiency of the impeller is reduced
Solution Approach 1:
Instead of adding material (balancing weights) to correct imbalances, the invention extracts or removes material by creating internal cavities within the impeller structure. This extraction approach achieves the necessary balance correction while minimizing interference with the hydraulic flow paths, thereby preserving hydraulic efficiency
4Ease of manufacture
If traditional casting methods are used, then manufacturing simplicity is maintained, but the ability to incorporate balancing features into the geometry is limited
Solution Approach 1:
The invention replaces traditional mechanical casting methods with additive manufacturing technology. This substitution enables complex internal cavity geometries to be created directly during manufacturing, providing both ease of manufacture and enhanced geometric design flexibility for integrating balancing features
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
The invention relates to an asymmetric pump impeller (1) for a pump unit for conveying a liquid which in particular contains solids, said impeller being formed at least to some extent in layers by an additive production method and having at least one cavity (5, 6) in the interior of the material of the impeller, said cavity being formed during the production in layers and closed completely towards the outside or except for an opening (7, 8) for removal of unhardened material from the cavity (5, 6). The cavity (5, 6) is positioned and designed in such a way that an inertia axis of the pump impeller (1) is displaced with respect to the axis of rotation (15) of the pump impeller (1). This has the advantage that the impeller is already largely free of unbalances immediately after the production or manufacture of the impeller, such that no or only minor subsequent balancing is required.