Check Valve Semi-Spherical Profile for Steam Flow Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional steam supply systems experience unstable suction pressure and inaccurate steam control due to the inherent flow characteristics of check valves, which lead to chattering and reduced flexibility in adjusting flow rates, especially when utilizing small amounts of re-evaporated steam.

Innovation Solution

The steam supply system incorporates a check valve with a valve body seated on an annular valve seat, featuring a flow rate controlling projecting portion with a semi-spherical shape, reducing the increase ratio of the flow rate in the small opening ratio range, thereby stabilizing steam passage and preventing chattering, and increasing it in the large opening ratio range for efficient steam handling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If the check valve has inherent flow characteristics with large increase ratio of flow rate in small opening ratio range, then the valve opens quickly for immediate closed state, but the suction pressure becomes unstable and chattering occurs

Engineering Contradiction:
Improvevalve opening speedVSAvoidsuction pressure stability
Core Design Contradiction:
SpeedVSStability of the object's composition

Solution Approach 1:

The patent changes the flow characteristics parameter of the check valve by adding a flow rate controlling projecting portion with semi-spherical shape. This modification alters the relationship between valve opening ratio and flow rate increase ratio, making it smaller in small opening ratio range to prevent chattering and larger in large opening ratio range to maintain quick response capability.

Inventive Principle:
Principle #35Parameter changes

2Loss of energy

If the valve opening ratio is adjusted to utilize small amounts of re-evaporated steam, then energy saving is improved, but chattering occurs and control accuracy deteriorates

Engineering Contradiction:
Improveenergy savingVSAvoidsteam control accuracy
Core Design Contradiction:
Loss of energyVSMeasurement precision

Solution Approach 1:

The patent modifies the flow rate characteristics parameter of the check valve to enable stable operation at small opening ratios. The semi-spherical projecting portion creates a flow rate increase ratio that is smaller in the small opening ratio range, allowing the valve to operate stably at low openings to utilize small amounts of re-evaporated steam without chattering, thereby improving energy saving while maintaining control accuracy.

Inventive Principle:
Principle #35Parameter changes

3Loss of time

If the check valve allows quick passage of re-evaporated steam, then the valve closed state is realized immediately, but the minimal adjustable flow rate is not large enough

Engineering Contradiction:
Improvetime to valve closed stateVSAvoidflow rate adjustability
Core Design Contradiction:
Loss of timeVSAdaptability or versatility

Solution Approach 1:

The patent changes the flow characteristics parameter by introducing the semi-spherical flow rate controlling projecting portion. This creates a non-linear flow rate increase ratio that is smaller in small opening ratio range (providing fine adjustability) and larger in large opening ratio range (enabling quick passage), thus resolving the contradiction between quick response and flow rate adjustability.

Inventive Principle:
Principle #35Parameter changes

4Adaptability or versatility

If the check valve operates with small opening ratio to control steam flow, then flexibility is improved, but chattering occurs and valve wear increases

Engineering Contradiction:
Improveflow rate flexibilityVSAvoidvalve operation stability
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent modifies the flow characteristics parameter by adding the semi-spherical projecting portion that creates a smaller flow rate increase ratio in the small opening ratio range. This allows the valve to operate flexibly at small openings without chattering, improving reliability and reducing valve wear while maintaining flow rate flexibility.

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

This configuration enhances the control accuracy of steam supply, prevents valve wear, and reduces maintenance costs by ensuring stable steam passage and efficient handling of both small and large amounts of re-evaporated steam, while maintaining high energy-saving efficiency.

Implementation Method 1

the valve opening being opened as the valve body moves away from the valve seat against the urging force of the urging means in response to a pressure of fluid entering the valve opening

Methodology Applied
Scientific EffectFluid pressure: Pressure Increase

Implementation Method 2

an urging means for providing an urging force for urging the valve body to a valve closing side

Methodology Applied
Scientific EffectElastic force: Spring

Data Source

PatentEP2484918B1Steam supply system and check valve used for same
Publication Date: 2020.01.22 TLV CO LTD
  • EP2484918B1 patent drawingFigure 1~2
  • EP2484918B1 patent drawingFigure 3(a)~3(b)
  • EP2484918B1 patent drawingFigure 4(a)~4(b)

AI summary

The accuracy of controlling steam by a pressure reducing valve is enhanced. A steam supply passage 1 incorporates a pressure reducing valve 3 and the passage 1 further incorporates a steam ejector 4 downstream of the pressure reducing valve 3. A suction portion 4a of the steam ejector 4 is connected to a re-evaporation tank 2 for re-evaporating steam condensate D1 via a suction passage 9. Passage steam S' of the pressure reducing valve 3 is used as a driving steam for the steam ejector 4. In operation, re-evaporated steam FS within the re-evaporation tank 2 is suctioned by the steam ejector 4 to be mixed with the passage steam S'. The suction passage 9 incorporates a check valve 10 for preventing reverse flow of steam to the re-evaporation tank 2, The steam supply system described above is configured such that a valve opening ratio of the pressure reducing valve 3 is adjusted in accordance with the temperature or the pressure of the steam on the downstream side of the steam ejector 4 in the steam supply passage 1 and the check valve 10 has an inherent flow characteristics that an increase ratio of a flow rate associated with increase of its valve opening ratio is equivalent between a small opening ratio range with small valve opening ratios and a large opening ratio range with large valve opening ratios or an inherent flow characteristics that the increase ratio is smaller in the small opening ratio range than in the large opening ratio range.