Stainless Steel Flanged Swing Check Valve
Flanged swing check valve cast in CF8 or CF8M stainless. Gravity swings the disc shut the moment flow stops. Three sizes — 2″, 3″ and 4″ — with ANSI Class 150 or JIS 10K flanges.
Bolted to the line, closed by gravity.
A flanged swing check valve — also sold as a flanged non return valve — has one job: let flow pass one way and shut the moment it tries to come back. Forward flow swings the disc clear of the full-bore path, so pressure drop stays low; when flow stops or reverses, gravity and back-pressure drop the disc onto the seat and the line is closed. No spring, no power, nothing to adjust.
The C series runs three sizes: the 2″ C-2F (DN50), the 3″ C-3F (DN80) and the 4″ C-4F (DN100). Each one is made with ANSI Class 150 (ASME B16.5) or JIS 10K (JIS B2220) flanges. The face-to-face length is the same either way, but the flanges are not, so order the standard your piping uses. Body, disc, arm and bolted bonnet are cast CF8 or CF8M — the cast forms of 304 and 316 stainless steel — poured in our own foundry and machined in-house in Taichung, Taiwan, with a PTFE bonnet gasket and SS304 / SS316 hardware.
For water, air and general service the CF8 build is the standard pick; chloride-bearing media — seawater-adjacent lines, brine, many process chemicals — call for CF8M, because the molybdenum in 316 resists chloride pitting. If you are comparing flanged check valve suppliers for an OEM run, note that casting, machining and assembly all happen on our own floor: one factory answers for the whole valve.
- C-2F · 2″ (DN50)
- C-3F · 3″ (DN80)
- C-4F · 4″ (DN100)
- Body
- A351 CF8 (304) or CF8M (316) — body, disc, arm and bonnet
- A351 CF8 (304) or CF8M (316) — body, disc, arm and bonnet
- A351 CF8 (304) or CF8M (316) — body, disc, arm and bonnet
- Size range
- 2″ (DN50)
- 3″ (DN80)
- 4″ (DN100)
- Flange
- ASME B16.5 Class 150 · JIS B2220 10K
- ASME B16.5 Class 150 · JIS B2220 10K
- ASME B16.5 Class 150 · JIS B2220 10K
- Pressure
- ANSI Class 150 / JIS 10K
- ANSI Class 150 / JIS 10K
- ANSI Class 150 / JIS 10K
- Temperature
- −20°C to 180°C
- −20°C to 180°C
- −20°C to 180°C
- Port
- Full bore
- Full bore
- Full bore
- Operation
- Self-acting — gravity-closed swing disc
- Self-acting — gravity-closed swing disc
- Self-acting — gravity-closed swing disc
Where it gets used
Every valve leak tested.
Each unit is checked for leakage before shipment.
Which way does it install?
On a horizontal run, cap up, with the arrow on the body pointing the way the flow goes. The disc hangs from its hinge and falls shut under its own weight, so orientation matters — for vertical lines, look at a spring check valve instead.
ANSI Class 150 or JIS 10K — which do I order?
Match whatever your piping flanges already are: Class 150 valves have ASME B16.5 flanges and JIS 10K valves have JIS B2220 flanges. All three sizes — 2″, 3″ and 4″ — come in both versions. The face-to-face length is the same either way; the flange diameter and bolt pattern are not, so order the one that matches your piping.
Should I pick CF8 or CF8M?
CF8 is cast 304 — the standard choice for water, air and general service. CF8M is cast 316: the added molybdenum resists chloride pitting, so specify it for seawater-adjacent, brine or chemically aggressive lines.
What is the difference between a flanged and a wafer check valve?
A wafer check is a thin disc clamped between two pipe flanges; it saves space but comes out only by spreading the line. A flanged swing check bolts in as its own spool piece — you can unbolt it, service the disc through the bolted bonnet and rebolt it without disturbing the rest of the run — and the full-bore swing design gives a lower pressure drop.
Do you take OEM orders under our brand?
Yes — that is most of what we do. SZ Valves casts and machines in-house in Taichung, Taiwan, so private label, customer part numbers and your documentation requirements are all on the table. Send sizes, flange standard and quantities for a quote.
