A ‌foot valve‌ (also called ‌bottom valve‌) is a specialized type of ‌check valve‌ designed to maintain unidirectional fluid flow in suction pipelines, primarily used in pump systems to prevent backflow and ensure efficient operation.  
 
‌Definition & Core Function‌
‌Purpose‌: Installed at the ‌lowest point‌ of a suction pipe (e.g., in wells or tanks), it allows fluid to enter the pump while blocking reverse flow when the pump stops, keeping the pipe primed for restart .
‌Mechanism‌: Uses a ‌valve disc‌ that opens via fluid pressure (forward flow) and closes by ‌gravity‌ or ‌spring force‌ (backflow) .
 
‌Applications‌
‌Pump Systems‌: Essential for ‌non-self-priming centrifugal pumps‌ to avoid dry starts.
‌Industrial Uses‌: Water supply, irrigation, chemical processing, and marine systems .
‌Tank Drainage‌: Ensures complete emptying without backflow (e.g., in storage tanks)