Self-Cleaning Screen Check Valve for Shallow Water Pumping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Centrifugal pumps face challenges in self-priming when starting from air-filled or dry conditions, with existing self-priming solutions being complex, expensive, and unreliable, and often unable to lift water high enough to prime the pump effectively.
Innovation Solution
A self-cleaning screen assembly with a rotatable drum and a check valve assembly that includes valve members with stems and faces to prevent backflow through inlet openings, maintaining prime in the pump by allowing water to flow in during operation and closing by gravity when stopped, ensuring the pump remains primed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a self-priming centrifugal pump is used to lift water from shallow conditions, then the pump can operate without manual priming, but the existing self-priming solutions are complex, expensive, and unreliable
Solution Approach 1:
The invention divides the self-priming function into separate components: a simple centrifugal pump, a screen assembly with check valves, and a suction chamber. This segmentation allows each component to perform its basic function reliably while collectively achieving self-priming, avoiding the need for complex integrated self-priming pump designs.
Solution Approach 2:
The screen assembly with check valves acts as an intermediary device between the water source and the pump. It maintains the prime by preventing backflow and keeping water in the suction chamber and pipe, enabling the simple centrifugal pump to achieve self-priming without complex internal modifications.
2Reliability
If a screen is used to prevent debris from entering the pump, then the pump is protected from damage, but the screen can become plugged by debris during pumping
Solution Approach 1:
The screen is designed to rotate during pump operation, transitioning from a static filtering surface to a dynamic component. This rotation allows debris to be swept off the screen surface by the rotating motion, preventing plugging while maintaining continuous filtration and pumping operation.
Solution Approach 2:
The rotating screen performs self-cleaning during normal pump operation. The rotation mechanism uses the pump's own operating conditions (water flow and rotation) to automatically clear debris from the screen, eliminating the need for separate cleaning systems or manual intervention.
3Use of energy by stationary object
If the pump is stopped, then energy is saved and operation is controlled, but water backflows through the inlet openings causing the pump to lose prime
Solution Approach 1:
The check valve assembly extracts and isolates the prime-maintaining function from the main pump system. When the pump stops, the check valve automatically closes to prevent backflow, maintaining the prime in the suction chamber and pipe independently of the pump's operational state, while still allowing energy-saving shutdowns.
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 effectively maintains prime in the pump, allowing for efficient and reliable operation without the need for repeated priming, even in shallow water conditions, by preventing backflow and ensuring water remains in the suction chamber and pipe when the pump is off.
Implementation Method 1
The valve members are movable upwardly from their closed positions to their open positions upon movement of water through the inlet openings into the suction chamber, and return to their closed positions by force of gravity when water stops flowing into the suction chamber.
Implementation Method 2
a rotatable drum having sidewalls made of a mesh material for removing debris from water as the water passes into the drum
Data Source
AI summary
A self-cleaning screen for shallow water pumping includes a rotatable drum made of mesh material for removing debris from water passing into the drum, and a suction chamber within the drum for feeding water to a suction pipe connected to a centrifugal pump. Inlet openings are arranged across a bottom side of the suction chamber. A check valve assembly is provided to prevent water from back flowing through the inlet openings, to thereby maintain a prime in the suction pipe when the pump is off. The check valve assembly includes valve members that are slidably mounted above the inlet openings for movement between closed and open positions. The valve members move upwardly from their closed positions to their open positions upon movement of water through the inlet openings into the suction chamber, and return to their closed positions by force of gravity when water stops flowing into the suction chamber.