A pump check valve has one job: let water leave and never let it back. When the valve or its flapper wears out, the line drains, the prime is lost, and the pump starts its day over. The fix is here, in stock, and sized to your line.
Elite Manufacturing Systems stocks swing check valves from 3 to 8 inches and replacement rubber flappers from 3 to 12 inches in BUNA, EPDM, and Viton, for the discharge lines on Cornell and Pioneer centrifugal pump systems. Every part is a compatible or improved aftermarket component, not OEM.
These are industrial check valves for agricultural irrigation, municipal water, oilfield, and manufacturing operations across the United States and Canada. They are not toilet flappers or residential plumbing check valves.
How a Swing Check Valve Works
A swing check valve is the simplest machine on the discharge line. Flow pushes the flapper open; reverse flow swings it shut against the seat.
That one motion protects the prime, keeps the column from draining back through the pump, and stops reverse spin on shutdown. The rubber flapper does the sealing work, which is why it wears first and why it is the part you replace most. When the seal starts weeping, swap the flapper before the whole valve gets blamed.
Pick the Right Flapper Material
A rubber flapper valve is a wear part, and the rubber compound decides how long it lasts in your service. Three compounds cover the range:
| Material | Sizes in Stock | Best For |
|---|---|---|
| BUNA (nitrile) | 3" to 12" | General water service; the economical everyday choice |
| EPDM | 3" | Hot water and weather-exposed service |
| Viton | 3" to 8" | Chemical exposure and higher temperatures |
Swing check valves themselves run 3 to 8 inches. Send your line size and what the pump moves, and we will match both the valve and the flapper compound.
Sizes from the Elite Manufacturing Systems catalog as of July 2026. If your size is not listed, call and the team will check.
Get Parts From Louisiana or West Texas
Order in-stock parts before 12pm Central and they ship the same day from Lake Charles, Louisiana, with UPS Red next-day air available on request. Need it in hand today? Pick up at the Lake Charles headquarters or at the Midland, Texas distribution center.
Check Valve Questions, Answered
A check valve is a one-way valve that lets water flow in a single direction and closes automatically when the flow tries to reverse. On centrifugal pump systems, a check valve sits on the discharge line so the pumped column cannot drain back through the pump when it stops. It needs no power or operator; the flow itself opens and closes it.
On a pump system, a check valve does three jobs: it holds the water column so the pump keeps its prime between runs, it prevents backflow from draining the line when the pump shuts down, and it stops the reverse flow that can spin a stopped pump backward. A worn check valve shows up as lost prime, longer restarts, and a line that drains overnight.
A check valve works on flow pressure alone. In a swing check valve, forward flow pushes a hinged flapper open and holds it open; when flow stops or reverses, gravity and back-pressure swing the flapper shut against its seat, sealing the line. The rubber flapper is the sealing element, so most check valve failures are really flapper failures, and replacing the flapper restores the seal.
To pick a check valve for well pump service or any agricultural water system, match the valve to the line size first: Elite Manufacturing Systems stocks swing check valves from 3 to 8 inches. Then match the flapper compound to the service, with BUNA for general water and Viton for chemical or hot service. If you are unsure, send the line size and pump model to (337) 564-6428 and the team will match the valve before you order.
No, these are not toilet flappers. The rubber flapper valves here are industrial sealing elements for the check valves on Cornell and Pioneer centrifugal pump discharge lines, sized 3 to 12 inches. A hardware store is the right source for toilet and residential plumbing flappers.
Yes, vacuum pump check valves keep air moving one way through the priming system on self-priming Cornell and Pioneer units, separate from the discharge check valve covered here. Inlet and exhaust valves for those reciprocating vacuum pumps live on the vacuum pumps page.
No, these are not OEM parts. Elite Manufacturing Systems supplies compatible or improved aftermarket check valves and flappers designed to fit Cornell and Pioneer pump systems, typically priced about 30% below OEM. Most items carry a manufacturer defect warranty, and issues are handled case by case.
To confirm a check valve or flapper fits your system, send Elite Manufacturing Systems the line size and your pump model or serial number before you order. Call (337) 564-6428, email Chad@elitemanufacturingsystems.com, or text a photo of the old valve or flapper. The team verifies the match and points you to the exact part in the catalog.