Expansive Gate Valve Venting for Thermal Cavity Pressure Relief

Solution Overview

Problem

Valves used in managing hot process fluids face issues with over-pressurization due to thermal expansion, leading to undesirable wear and reduced lifespan, as existing valves do not effectively prevent fluid pressure increase within their cavities.

Innovation Solution

A gate valve design featuring first and second flow control elements that transition between open and closed positions, preventing a fluid tight seal in the open position to allow pressurized fluid to escape from the valve's cavity, thereby reducing the risk of over-pressurization, and including an actuator assembly for manual or powered operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the valve maintains a fluid tight seal in the open position, then flow control precision is improved, but over-pressurization occurs due to thermal expansion of fluids in the cavity

Engineering Contradiction:

Improveflow control precisionVSAvoidcavity pressure

Core Design Contradiction:

Measurement precisionVSStress or pressure

Solution Approach 1:

The valve is divided into two functional zones: a sealed flow path for precise flow control and an unsealed cavity space for pressure relief. The flow control elements seal against valve seats to control process fluid flow, while the cavity remains open to allow thermal expansion of lubricating fluid without over-pressurization.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different parts of the valve have different sealing characteristics. The flow control surfaces between the flow control elements and valve seats are designed to be sealing to enable precise flow control, while the cavity surfaces are intentionally non-sealing to allow pressure equalization during thermal expansion.

Inventive Principle:

Principle #3Local quality

2Stress or pressure

If the valve allows fluid to escape from the cavity, then over-pressurization is prevented, but flow control sealing is compromised

Engineering Contradiction:

Improvecavity pressureVSAvoidflow control sealing

Core Design Contradiction:

Stress or pressureVSReliability

Solution Approach 1:

The valve is divided into two functional zones: a sealed flow path for precise flow control and an unsealed cavity space for pressure relief. The flow control elements seal against valve seats to control process fluid flow, while the cavity remains open to allow thermal expansion of lubricating fluid without over-pressurization.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different parts of the valve have different sealing characteristics. The flow control surfaces between the flow control elements and valve seats are designed to be sealing to enable precise flow control, while the cavity surfaces are intentionally non-sealing to allow pressure equalization during thermal expansion.

Inventive Principle:

Principle #3Local quality

3Productivity

If the valve uses a traditional sealing design, then flow control is effective, but wear increases and useful life is reduced due to thermal expansion pressures

Engineering Contradiction:

Improveflow control effectivenessVSAvoidvalve useful life

Core Design Contradiction:

ProductivityVSDuration of action of stationary object

Solution Approach 1:

The valve is divided into two functional zones: a sealed flow path for precise flow control and an unsealed cavity space for pressure relief. The flow control elements seal against valve seats to control process fluid flow, while the cavity remains open to allow thermal expansion of lubricating fluid without over-pressurization.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The design converts the potentially harmful effect of thermal expansion into a beneficial feature by allowing the cavity to expand freely. The open cavity design lets thermal expansion pressures be relieved rather than building up to cause wear, thereby extending valve life while maintaining flow control effectiveness.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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 gate valve effectively controls the flow of hot process fluids, preventing over-pressurization by allowing pressurized fluid to escape, thus reducing wear and extending the valve's useful life by maintaining a non-sealing position during fluid flow, which helps in managing thermal expansion pressures.

Implementation Method 1

over-pressurization of a valve due to thermal expansion of fluids not in the flow path

Methodology Applied

Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentUS11149859B2Close only expansive gate valve

Publication Date: 2021.10.19 CAMERSON INT CORP

AI summary

A system, including a first flow control element configured to couple to a stem, and a second flow control element coupled to the first flow control element, wherein the first and second flow control elements are configured to expand relative to one another to create a seal in a closed position between a chamber and a flow path in a valve body, and wherein the first and second flow control elements are configured to enable fluid flow between the chamber and the flow path in an open position.