Bi-Furcated Valve Plug Gap Control for High-Temperature Seal Wear

Solution Overview

Problem

Valve assemblies face challenges in regulating movement and preventing over-travel of bi-furcated plugs at extreme temperatures, leading to unnecessary wear and stress on resilient seals due to thermal expansion, which can result in costly maintenance and repairs.

Innovation Solution

A gap control device with a hard stop mechanism that actively controls the relative travel between the plug parts, using a thermally-active member with a specific coefficient of expansion to maintain a consistent gap dimension, reducing stress and wear on the seal, and allowing the use of less costly materials while meeting stringent high-temperature operation requirements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If the plug parts are allowed to move freely at high temperatures, then the valve can operate at extreme temperatures, but thermal expansion causes over-travel and excessive stress on the resilient seal

Engineering Contradiction:

Improveoperating temperatureVSAvoidseal stress and wear

Core Design Contradiction:

TemperatureVSReliability

Solution Approach 1:

The patent introduces a gap control device that actively adjusts and maintains a specific gap dimension between plug parts despite thermal expansion. This parameter control prevents over-travel and excessive seal stress while allowing operation at extreme temperatures, directly resolving the contradiction between temperature capability and seal reliability

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The gap control device acts as an intermediary mechanism between the thermally-active member and the resilient seal. It mediates the thermal expansion effects by controlling the gap dimension, thereby protecting the seal from direct stress caused by uncontrolled expansion while maintaining high-temperature operation capability

Inventive Principle:

Principle #24Intermediary (Mediator)

2Temperature

If expensive high-temperature resistant materials are used for the plug, then the valve can withstand extreme temperatures, but construction costs increase significantly

Engineering Contradiction:

Improvetemperature resistanceVSAvoidconstruction cost

Core Design Contradiction:

TemperatureVSEase of manufacture

Solution Approach 1:

The patent introduces a gap control device that actively adjusts and maintains a specific gap dimension between plug parts despite thermal expansion. This parameter control prevents over-travel and excessive seal stress while allowing operation at extreme temperatures, directly resolving the contradiction between temperature capability and seal reliability

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The gap control device acts as an intermediary mechanism between the thermally-active member and the resilient seal. It mediates the thermal expansion effects by controlling the gap dimension, thereby protecting the seal from direct stress caused by uncontrolled expansion while maintaining high-temperature operation capability

Inventive Principle:

Principle #24Intermediary (Mediator)

3Adaptability or versatility

If the resilient seal is designed to accommodate large movements, then over-travel is permitted, but the seal experiences excessive wear and reduced service life

Engineering Contradiction:

Improvemovement accommodationVSAvoidseal service life

Core Design Contradiction:

Adaptability or versatilityVSDuration of action of stationary object

Solution Approach 1:

The patent introduces a gap control device that actively adjusts and maintains a specific gap dimension between plug parts despite thermal expansion. This parameter control prevents over-travel and excessive seal stress while allowing operation at extreme temperatures, directly resolving the contradiction between temperature capability and seal reliability

Inventive Principle:

Principle #35Parameter changes

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 ensures repeatable and predictable movement of the plug parts, extends the life of resilient seals, and reduces construction costs by allowing the use of cost-effective materials while maintaining effective zero-leakage performance even at extreme temperatures.

Implementation Method 1

a thermally-active member with a specific coefficient of expansion to maintain a consistent gap dimension, reducing stress and wear on the seal

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentUS11079032B2Regulating overtravel in bi-furcated plugs for use in valve assemblies

Publication Date: 2021.08.03 DRESSER LLC

AI summary

A gap control device that works with a plug on a valve assembly for use in high-temperature applications. The plug may include two parts and a compressible seal that, when compressed, engages with an adjacent wall of a cylinder or “cage” typical of a trim assembly. In one embodiment, the gap control device forms a hard stop that expands in response to high temperatures. This feature prevents excess over-travel between the two parts of the plug in the high-temperature applications so as to limit stress and wear on the compressible seal.