Pump Sealing Element Dynamics for Wear Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing pumps used in mining and similar environments face challenges with reliable sealing due to wear from sand and particles, especially when operating without cooling fluid, leading to inefficiencies and reduced longevity.

Innovation Solution

A pump design featuring a sleeve-shaped sealing element that is slightly shorter than the distance between impellers, allowing it to move and maintain contact only at specific pressure points, reducing wear and enabling the use of strong, wear-resistant materials, along with an annular elastic sealing to manage pressure differences and prevent damage during startup.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If mechanical resilient sealings are used to seal gaps between moving parts, then sealing reliability is improved, but the seals are destroyed by overheating when running with low or without cooling fluid

Engineering Contradiction:
Improvesealing reliabilityVSAvoidseal temperature
Core Design Contradiction:
ReliabilityVSTemperature

Solution Approach 1:

The sealing element is designed to be movable along the drive shaft axis, dynamically adjusting its position between the first and second impellers based on pressure differentials. This mobility allows the sealing element to maintain sealing effectiveness while avoiding overheating damage by enabling pressure equalization and reducing thermal stress concentration.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The sealing element's length is specifically designed to be smaller than the distance between the first and second impellers, creating a pressure-driven positioning system. This parameter change enables the sealing element to move to optimal positions under different operating conditions, preventing overheating while maintaining sealing reliability.

Inventive Principle:
Principle #35Parameter changes

2Duration of action of moving object

If the sealing element length is reduced to be smaller than the distance between impellers, then wear resistance is improved, but sealing effectiveness may be compromised

Engineering Contradiction:
Improvesealing element lifespanVSAvoidsealing effectiveness
Core Design Contradiction:
Duration of action of moving objectVSReliability

Solution Approach 1:

The sealing element's shorter length is compensated by its dynamic mobility along the drive shaft. The element can move to maintain optimal sealing contact with the impellers while reducing overall wear exposure, thus extending lifespan without sacrificing sealing effectiveness.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The sealing element uses the pressure differential between the first and second impellers to automatically position itself, eliminating the need for external actuation mechanisms. This self-positioning capability ensures continuous sealing effectiveness despite the reduced length.

Inventive Principle:
Principle #25Self-service

3Strength

If the sealing element is made of strong wear-resistant material, then durability in particle-containing fluid is improved, but manufacturing complexity increases

Engineering Contradiction:
Improvewear resistanceVSAvoidsealing element manufacturing
Core Design Contradiction:
StrengthVSEase of manufacture

Solution Approach 1:

The sealing element features different transverse areas at its ends, with the first area being larger than the second area. This local quality variation optimizes the distribution of forces from pressure differences while maintaining wear resistance in critical areas, balancing material strength requirements with manufacturability.

Inventive Principle:
Principle #3Local quality

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 solution provides reliable sealing and extended pump lifespan by minimizing wear and preventing damage from particle flow, while allowing for adjustable sealing elements and replaceable components to maintain performance over time.

Implementation Method 1

said sealing element is movable along axis A between the first and second impeller... the force exerted by the lower pressure generated by the first impeller and the first area is substantially equal to the force exerted by the higher pressure generated by the second impeller and the second area

Methodology Applied
Scientific EffectPressure difference: Pressure Gradient

Data Source

PatentEP3486491B1Pump for a fluid
Publication Date: 2020.09.30 SULZER MANAGEMENT AG
  • EP3486491B1 patent drawingFigure 1
  • EP3486491B1 patent drawingFigure 2a~2b
  • EP3486491B1 patent drawingFigure 2c

AI summary

The present invention relates to a pump (10) for fluids. The pump comprising: a pump housing (11); a power source (8); a drive shaft (6) connected to the power source (8) and extending along an axis A; a fluid inlet (14); a first impeller (22) rotated by said drive shaft and comprising a first impeller inlet (221) in fluid connection with the fluid inlet, and a first impeller outlet; a second impeller (23) rotated by said drive and comprising a second impeller inlet (231) in fluid connection with the first impeller outlet, and a second impeller outlet; and a sealing element (30) stationary arranged in relation to the drive shaft and first and second impeller, said sealing element is sleeve shaped and arranged between the first and second impeller around the drive shaft, said sealing element has a first end (32) transvers to the drive shaft and facing the first impeller and a second end (33) transverse to the drive shaft facing the second impeller, said sealing element has a length along axis A smaller than the distance between the first and second impeller such that the sealing element is movable along axis A between the first and second impeller, wherein the first end (32) of the sealing element has a first area (35) transverse to axis A and the second end (33) has a second area (36) transverse to axis A, and said first area is larger than said second area such that the force exerted by the lower pressure generated by the first impeller and the first area is substantially equal to the force exerted by the higher pressure generated by the second impeller and the second area.