Centrifugal Pump Impeller Scraper for Deposit Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Centrifugal pumps face challenges in handling media that form deposits, leading to operational issues and the need for specialized parts, which complicates production and maintenance, especially when dealing with solid-forming media.
Innovation Solution
An impeller design with a scraper integrally connected at two points, creating a cleanable gap between the scraper and the impeller, allows for the removal of deposits and uses standard parts, preventing distortion and simplifying production, while a spacer element can be added to increase media compatibility by ensuring the gap remains unobstructed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a scraper is bonded to the impeller using large-area bonding (e.g., welding), then the connection strength is improved, but the impeller experiences stress and distortion due to heat input
Solution Approach 1:
The bonding area is segmented into multiple discrete bonding locations (first and second locations) spaced apart from each other, rather than large-area continuous bonding. This segmentation reduces the total heat input area and prevents widespread stress and distortion in the impeller while maintaining sufficient connection strength at each bonding point
Solution Approach 2:
The bonding is concentrated at specific localized areas (first and second locations) rather than distributed uniformly across the scraper. This local quality approach applies bonding strength only where necessary for structural integrity, minimizing thermal impact zones and preventing impeller distortion while maintaining connection strength
2Ease of manufacture
If standard impeller parts are used for centrifugal pumps handling media with solids, then production cost is reduced, but deposits form on the impeller and housing wall causing operational issues
Solution Approach 1:
The scraper is pre-installed on the standard impeller before the impeller is placed into service. This preliminary action prevents deposits from forming and adhering to the impeller and housing wall during operation, maintaining operational reliability while using cost-effective standard impeller parts
Solution Approach 2:
The scraper continuously removes deposits as the impeller rotates, enabling the system to self-maintain operational reliability without external intervention. This self-service mechanism allows standard impeller parts to handle solid-forming media reliably by automatically preventing deposit accumulation
3Adaptability or versatility
If the gap between the impeller and housing wall is increased to prevent deposit buildup, then media compatibility is improved, but the pump efficiency decreases
Solution Approach 1:
The scraper acts as an intermediary element between the impeller and housing wall, enabling the gap to remain small for efficiency while still preventing deposit buildup. The scraper mechanically removes deposits that would otherwise require a larger gap to prevent, thus maintaining both pump efficiency and media compatibility
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to an impeller for a centrifugal pump (1), comprising a housing (2), an inlet (3), an outlet (4), and a chamber (13) which is provided in the housing (2) in fluidic connection with the inlet (3) and the outlet (4). The impeller (14, 414, 514, 614, 714, 814, 914, 1014, 1114, 1214) is received in the chamber (13) in a rotatable manner, and a gap (24) is provided between a rear face (22, 422, 522, 622, 722, 822, 922, 1022, 1122, 1222) of the impeller (14, 414, 514, 614, 714, 814, 914, 1014, 1114, 1214) and a housing wall (23). The aim of the invention is to improve the compatibility with media which form deposits. This is achieved in that the impeller (14, 414, 514, 614, 714, 814, 914, 1014, 1114, 1214) has at least one scraper (25, 425, 525, 625, 725, 825, 925, 1025, 1125, 1225) which is bonded to the impeller (14, 414, 514, 614, 714, 814. 914, 1014, 1114, 1214) at a first location (444, 544, 644, 744, 944, 1044, 1144) and a second location (445, 545, 645, 745, 945, 1045, 1 145). The first location (444, 544, 644, 744, 944, 1044, 1144) and the second location (445, 545, 645, 745, 945, 1045, 1145) are spaced apart, and a cleanable intermediate space (548, 648, 748, 948, 1048, 1148) is produced in the spacing between the scraper (25, 425, 525, 625, 725, 825, 925, 1025, 1125, 1225) and the rear face (22, 422, 522, 622, 722, 822, 922, 1022, 1122).