Valve Controller Relay Pulsing for Pneumatic Bleed Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional valve controllers experience significant pneumatic medium wastage due to persistent bleed, especially during steady-state operations, which leads to inefficiencies in pneumatic medium conservation and increased operational costs.
Innovation Solution
The implementation of a valve controller with a two-stage relay system, where first and second relay valves are controlled by corresponding I/P converters, reduces or eliminates the persistent bleed by pulsing the relay valves between closed and open positions, thereby optimizing pneumatic volume usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional valve controllers continuously supply pneumatic medium to maintain output signal, then the control valve position is maintained, but significant pneumatic medium is wasted due to persistent bleed
Solution Approach 1:
The patent applies periodic action by switching from continuous pneumatic supply to intermittent pulsing of the relay valve. The controller pulses the relay valve only when position adjustment is needed, rather than continuously supplying pneumatic medium. This periodic operation maintains the control valve position while dramatically reducing pneumatic medium consumption and waste.
Solution Approach 2:
The patent extracts the harmful continuous bleed component from the system by implementing a relay valve that can be completely closed. This separates the position maintenance function from continuous pneumatic flow, allowing the system to maintain valve position without the harmful continuous bleed that wastes pneumatic medium.
2Quantity of substance
If upstream pressure sensors and flow meters are implemented to measure total pneumatic medium usage, then consumption data is obtained, but the system cannot differentiate between useful usage and wasted bleed
Solution Approach 1:
The patent implements feedback by using downstream pressure sensors to monitor the actual pneumatic medium consumption at the control valve. This feedback mechanism allows the system to distinguish between pneumatic medium used for position adjustment (useful) versus continuous bleed (waste), providing efficiency differentiation data that upstream sensors alone cannot provide.
Solution Approach 2:
The patent introduces an intermediary measurement system using downstream pressure sensors that act as a mediator between the pneumatic medium flow and the control system. This intermediary provides specific information about actual consumption patterns, enabling the system to differentiate between useful usage and waste without requiring complex upstream measurement infrastructure.
3Loss of substance
If relay valve is pulsed between closed and open positions to reduce bleed, then pneumatic medium conservation is improved, but the system complexity increases with two-stage relay control
Solution Approach 1:
The patent uses the relay valve as an intermediary component that simplifies the overall control architecture. Although the relay valve itself adds a component, it eliminates the need for complex continuous control mechanisms and enables simple on/off pulsing operation, thereby reducing system complexity while improving pneumatic medium conservation.
Solution Approach 2:
The patent replaces complex continuous mechanical pneumatic control with simpler electronic pulsing control of the relay valve. The electronic control system triggers intermittent relay valve activation, substituting complex continuous mechanical adjustment with simpler periodic electronic switching, thereby reducing overall system complexity while achieving better conservation.
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 approach effectively quantifies pneumatic volume usage, reduces wastage, and enhances the efficiency of pneumatic medium conservation, leading to economic and environmental benefits.
Implementation Method 1
command a current-to-pressure (I/P) converter of the valve controller to pulse a relay valve
Data Source
AI summary
Methods and apparatus for quantifying pneumatic volume usage via valve controllers are disclosed. An example apparatus includes a valve controller operatively couplable to a pneumatic actuator, the pneumatic actuator being operatively coupled to a control valve. In response to an input signal indicating that a flow control member of the control valve is to be moved in a specified direction, the valve controller commands a current-to-pressure (I/P) converter of the valve controller to pulse a relay valve of the valve controller between a closed position and an open position. The pulsing of the relay valve causes the pneumatic actuator to move the flow control member in the specified direction. The valve controller calculates a pneumatic volume usage associated with the moving of the flow control member in the specified direction. The pneumatic volume usage is based on the pulsing of the relay valve.