A stainless steel flap valve is an automatic gravity-operated check valve designed for one-way flow control.It freely opens under forward water pressure and automatically closes tightly via reverse pressure and self-weight to completely prevent backflow.Made of high-grade stainless steel overall,it is the most durable and anti-corrosion solution among all flap valve series,widely adopted in harsh working conditions.

Working Principle

Without any electric power,manual operation or auxiliary control system,the valve works purely by hydraulic pressure difference.

When fluid flows forward,the water pressure pushes the stainless steel flap open to realize unobstructed water discharge.

When upstream flow stops,or downstream backwater,tide rise,flood backflow occurs,the flap quickly rebounds and seals closely with the valve seat under reverse pressure and gravity,cutting off reverse flow thoroughly and avoiding water pouring back into pipelines,pump stations and drainage networks.

Main Materials

Valve Body:Stainless steel 304/316L,high structural strength,overall precision welding molding.

Flap Disc:Integral stainless steel plate,high rigidity,no deformation under long-term water impact.

Hinge Shaft&Fittings:Solid 316 stainless steel,anti-loosening,flexible rotation,no jamming.

Sealing Ring:High elasticity EPDM/NBR rubber seal,excellent water tightness,aging resistance and wear resistance.

Key Features

Superior Corrosion Resistance

Perfectly resistant to seawater,brine,acidic sewage,alkaline wastewater and chemical media corrosion.No rust,no corrosion peeling,far better than cast iron and ordinary plastic valves.

Ultra-long Service Life

Stable mechanical performance,strong impact resistance,almost no structural damage under long-term underwater operation.

Reliable Sealing Performance

Precise matching between disc and seat,low leakage rate,efficient backflow prevention even under slight pressure difference.

Low Flow Resistance

Smooth internal channel design,small head loss,ensuring high-efficiency fluid discharge.

Simple Structure&Low Maintenance

Few moving parts,sturdy hardware,no frequent maintenance,paint or anti-rust treatment required.

Wide Environmental Adaptability

Adapt to deep water,high humidity,outdoor exposed,coastal high-salt fog harsh environments.

Technical Specifications

Body Material:SS304,SS316L

Seal Material:EPDM,NBR

Hinge&Fastener:Stainless Steel 316

Size Range:DN50~DN3000,circular&rectangular customized available

Working Pressure:PN6,PN10,PN16

Connection:Flanged,wall-mounted,pipeline direct connection

Working Temperature:-20℃~90℃

Applicable Medium:Fresh water,sewage,seawater,industrial wastewater

Applications

Coastal drainage and tidal backflow prevention projects

Seawater intake and discharge pipelines of marine engineering

Chemical industry wastewater discharge with corrosive media

Municipal sewage treatment plant outlet pipelines

Pump station outlet anti-backflow equipment

High-standard water conservancy,flood control and drainage engineering