Seal Device Pumping Grooves Radial Flow Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional non-contact hydrostatic sealing devices experience reduced sealing performance due to excessive sealing gas flowing from the high-pressure fluid side to the low-pressure fluid side, leading to leakage.

Innovation Solution

The sealing device incorporates static pressure grooves and pumping grooves, specifically spiral grooves, to control the radial flow of sealing gas from the low-pressure fluid side to the high-pressure fluid side, reducing leakage and enhancing sealing performance by generating dynamic pressure at the downstream ends of the grooves.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If sealing gas is supplied between the sliding faces from the fluid supply source through the sealing gas supply passage, then a floating gap is formed and sealing gas barrier is created, but sealing gas flows to both high-pressure fluid side and low-pressure fluid side, causing excessive flow to low-pressure side and reducing sealing performance

Engineering Contradiction:
Improvesealing performanceVSAvoidflow amount of sealing gas to low-pressure fluid side
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The invention segments the sealing gas flow path by introducing pumping grooves that divide the sliding face into different functional zones. These grooves create separate flow paths that control and direct sealing gas movement, preventing uncontrolled flow to the low-pressure side while maintaining the sealing barrier function.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The pumping grooves act as intermediary structures between the sealing gas supply and the sliding faces. They mediate the flow of sealing gas by generating dynamic pressure that controls the radial flow direction, thereby regulating how much sealing gas reaches the low-pressure fluid side while preserving sealing effectiveness.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If pumping grooves are introduced to control radial flow of sealing gas, then flow to low-pressure fluid side is reduced and sealing performance is improved, but device structure becomes more complex

Engineering Contradiction:
Improvesealing performanceVSAvoidstructure complexity of sliding faces
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention merges the sealing function and flow control function into a single integrated structure. The pumping grooves are formed directly on the sliding faces, combining the sealing surface with the flow control mechanism, thereby avoiding additional separate components and reducing overall device complexity while achieving improved sealing performance.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The sliding faces are designed with multi-functionality, serving both as sealing surfaces and as flow control elements. The pumping grooves enable the sliding faces to simultaneously maintain contact sealing while controlling radial flow distribution, eliminating the need for separate flow control devices and simplifying the overall structure.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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

This configuration effectively reduces the flow of sealing gas to the low-pressure fluid side, improves sealing performance, and maintains non-contact hydrostatic sealing functionality even with reduced sealing gas supply by widening the gap between sliding faces.

Implementation Method 1

pumping grooves capable of controlling a radial flow of sealing gas to a flow from an inner peripheral side of the pair of sliding components (a low-pressure fluid side) to an outer peripheral side of the pair of sliding components (a high-pressure fluid side) by relative sliding of the sliding faces

Methodology Applied
Scientific EffectDynamic pressure generation: Pressure Gradient

Implementation Method 2

a floating gap of ten-odd micrometers is formed by static pressure generated between the sliding faces, and a sealing gas barrier is formed in the gap

Methodology Applied
Scientific EffectStatic pressure generation: Pressure Gradient

Data Source

PatentEP3318784B1Seal device
Publication Date: 2020.07.01 EAGLE INDS
  • EP3318784B1 patent drawingFigure 1
  • EP3318784B1 patent drawingFigure 2
  • EP3318784B1 patent drawingFigure 3(a)~3(b)

AI summary

By controlling the radial flow of sealing gas at a sliding face, the amount of flow of the sealing gas flowing to the low-pressure fluid side is reduced to improve sealing performance. A pair of sliding components that slide relative to each other is included. One of the sliding components is a stationary-side seal ring 2, and the other sliding component is a rotating-side seal ring 3. The seal rings 2 and 3 have sliding faces S2 and S3 extending radially, respectively, for sealing sealed fluid against leakage. The sliding faces S2 and S3 of the pair of sliding components 2 and 3 are provided with a static pressure groove 22 communicating with a sealing gas supply passage, and pumping grooves 5 capable of controlling the radial flow of sealing gas to a flow from the low-pressure fluid side to the high-pressure fluid side by relative sliding of the sliding faces.