Vacuum Pump Multi-Stage Corrosion Resistance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Vacuum pumps fail when pumping corrosive fluids due to corrosion-induced deposit buildup, particularly at the final stages, leading to reduced running clearances and eventual pump failure, with existing corrosion-resistant materials being expensive.

Innovation Solution

A dry vacuum pump design with distinct sections made from different materials, where the first section (e.g., spheroidal graphite iron) is less resistant than the second section (e.g., Nickel rich spheroidal graphite iron, cast stainless steel, or Nickel alloy), ensuring that corrosive deposit buildup is minimized and evenly distributed across stages, reducing material costs while maintaining corrosion resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the pumping mechanism is made from corrosion-resistant material, then pump reliability is improved, but manufacturing cost increases

Engineering Contradiction:
Improvepump reliabilityVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The pumping mechanism is divided into sections with different material properties matched to local corrosion conditions. The first section uses less expensive material while the second section uses more corrosion-resistant material, optimizing both cost and reliability by applying material properties locally rather than uniformly throughout the entire pumping mechanism.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The pumping mechanism is segmented into multiple sections along the fluid flow path, with each section using appropriately selected materials based on the corrosivity conditions at that location. This segmentation allows differential material selection to reduce overall cost while maintaining reliability where most needed.

Inventive Principle:
Principle #1Segmentation

2Reliability

If uniform corrosion-resistant material is used throughout, then pump reliability is improved, but material cost increases

Engineering Contradiction:
Improvepump reliabilityVSAvoidmaterial cost
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

Different material grades are applied to different sections of the pumping mechanism based on the local corrosion environment. The second section experiences higher corrosivity and uses more corrosion-resistant material, while the first section uses less expensive material, optimizing material cost while maintaining overall pump reliability.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The material composition parameter is changed across different sections of the pumping mechanism to match the varying corrosion conditions. By adjusting material parameters locally rather than using a uniform high-grade material throughout, the solution reduces total material cost while maintaining the reliability needed in critical high-corrosion areas.

Inventive Principle:
Principle #35Parameter changes

3Object-generated harmful factors

If corrosion-resistant material is used, then deposit buildup is reduced, but manufacturing complexity increases

Engineering Contradiction:
Improvedeposit buildupVSAvoidmanufacturing complexity
Core Design Contradiction:
Object-generated harmful factorsVSDevice complexity

Solution Approach 1:

The pumping mechanism uses different material compositions in different sections to match the varying corrosivity and deposit buildup conditions along the fluid flow path. This local differentiation reduces deposit buildup in high-corrosion areas while keeping the overall design manageable by applying material variations only where necessary rather than throughout the entire system.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP2425137B1Vacuum pump
Publication Date: 2024.10.23 EDWARDS LTD
  • EP2425137B1 patent drawingFigure 1
  • EP2425137B1 patent drawingFigure 2
  • EP2425137B1 patent drawingFigure 3

AI summary

A multi stage vacuum pump for pumping corrosive fluid with a first flow section of material less resistant to corrosion than the material of a second flow section downstream of the first flow section.