Threaded Swing Check Valve
Threaded swing check valve cast in 316 (CF8M), 200 PSI (WOG), API 598 tested. Eight sizes from 1/2″ to 3″ with PT female threads. Closes on gravity and reverse flow — no spring, no power.
Gravity does the closing.
A swing check valve stops backflow with nothing but a disc and gravity. Forward flow pushes the hinged disc open; when the flow stops or reverses, the disc drops shut against the body seat. There is no spring to fatigue, no actuator to power and nothing to set — which is why it remains the default check valve on pump discharge and water lines.
The SC runs eight sizes: 1/2″, 3/4″, 1″, 1-1/4″, 1-1/2″, 2″, 2-1/2″ and 3″. Body, cap and disc are all cast CF8M, the cast form of 316 stainless steel, poured in our own foundry and machined on our own floor in Taichung, Taiwan. The cap and disc gaskets are PTFE; the hinge bolt and the plug are SUS 316. Ends are PT (Rc) female taper threads as stock, and other thread forms are made to order.
Rated 200 PSI (WOG) — 200 psi on cold water, oil or gas. Every valve is leak tested before it ships, the SC is tested to API 598, and a mill test report for the body material is available on request.
Because the disc closes under its own weight, orientation matters. The valve is built for horizontal pipe runs with the cap uppermost, or for vertical runs where the flow travels upward. The arrow cast into the body shows which way it goes.
- Model
- SC
- Body
- CF8M (cast 316) — stock
- Size range
- 1/2″–3″
- Thread
- PT (Rc) female — stock
- Pressure
- 200 PSI (WOG)
Where it gets used
Every valve leak tested.
Each unit is checked for leakage before shipment.
Which way round does it install?
Follow the arrow cast into the body — it points in the direction of flow. The valve is designed for horizontal pipe runs with the cap uppermost, so the disc hangs from the hinge and falls shut under its own weight when flow stops.
Can I fit it in a vertical line?
Yes, provided the flow travels upward through the valve. In a vertical run with downward flow the disc will not seat reliably, because gravity is then working to hold it open rather than shut it.
What is CF8M?
CF8M is the cast form of 316 stainless steel, specified under ASTM A351. It contains molybdenum, which improves resistance to chloride pitting compared with CF8, the cast form of 304. When a valve body is cast rather than machined from bar stock, CF8M is the grade you should see written on the quotation.
What does 200 PSI (WOG) mean?
WOG stands for water, oil and gas — it is a cold working pressure rating. The valve is rated for 200 psi on those media at ambient temperature. It is not a temperature rating and says nothing about hot service.
Which threads do you supply?
PT (Rc) female taper threads are stock across all eight sizes. NPT and other thread forms are made to order — send us the size and the thread standard with your enquiry.
