Valve Positioner Bypass Component for Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Digital-based valve positioners in control valves face reliability issues, leading to extended downtime and costly production delays, with existing solutions either requiring manual intervention, adding complexity, or increasing hardware and software costs.
Innovation Solution
Incorporating a by-pass component that utilizes control input signals to maintain operation of the control valve, allowing for in-situ repair and modulation of fluid flow without digital microprocessors, enabling continuous operation during maintenance and reducing downtime.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If digital-based valve positioners are used to improve control precision and functionality, then measurement precision and adaptability are improved, but reliability deteriorates due to component failures
Solution Approach 1:
The valve positioner is divided into two independent operational paths: a primary digital control path using microprocessors for precise control, and a secondary analog bypass path using operational amplifiers for reliable fallback operation. This segmentation allows the system to maintain functionality even when the digital components fail, resolving the contradiction between precision and reliability.
Solution Approach 2:
The system changes operational parameters by switching between digital signal processing (for precision) and analog signal processing (for reliability). The bypass component uses operational amplifiers to process control signals in an analog manner, providing a reliable alternative when digital components fail, thus maintaining control precision through parameter change rather than physical replacement.
2Reliability
If redundant control valves and fluid circuits are integrated to maintain operation during repairs, then reliability is improved, but device complexity and cost increase
Solution Approach 1:
The bypass component is integrated within the existing valve positioner housing, merging the backup analog control functionality into the same physical device rather than requiring separate redundant valves and fluid circuits. This consolidation maintains reliability while significantly reducing device complexity and component cost.
Solution Approach 2:
The valve positioner is designed with multi-functionality, serving both as a primary digital control device and as an analog control device through the bypass component. This universal design eliminates the need for separate redundant systems, reducing complexity while maintaining the ability to continue operation during repairs.
3Reliability
If mechanical actuators are used instead of digital components to improve reliability, then reliability is improved, but ease of operation deteriorates due to manual intervention requirements
Solution Approach 1:
The bypass component acts as an intermediary that automatically transfers control from the digital microprocessor to the analog operational amplifier circuitry when digital components fail. This automatic intermediary function maintains ease of operation by eliminating the need for manual intervention, while the analog bypass path provides improved reliability.
Data Source
AI summary
A valve positioner that can maintain operation of the control valve despite failures in one or more components. The valve positioner may reduce downtime by allowing in-situ repair to occur on the valve positioner. The valve positioner may incorporate a by-pass component, which can utilize control input signals (e.g., a 4-20 mA signal) to energize one or more components (e.g., a current-to-pressure converter) to cause the control valve to modulate fluid flow without the digital microprocessor and/or related components.