1/2 in. 316 Stainless Steel Inline Check Valve | 949403
1/2 in. 316 Stainless Steel Inline Check Valve | 949403
The 1/2 in. 316 stainless steel inline check valve (part 949403) delivers spring-loaded, bubble-tight backflow protection for chemical and corrosive service. ASTM A351-CF8M investment-cast body, soft PTFE seat, and a dual-guided stem and disc that seats fast at just 1/2 psi cracking pressure. Rated 800 psi WOG and 125 psi WSP saturated steam across a +10°F to 450°F range. Female NPT both ends. Made in Italy.
Technical Specifications
| Manufacturer Part Number (MPN) | 949403 |
| Nominal Size | 1/2 in. |
| Valve Type | Inline check valve (spring-loaded poppet), 316 stainless steel |
| End Connections | Female NPT × Female NPT, ANSI B1.20.1 |
| Pressure Rating | 800 psi WOG |
| Steam Rating | 125 psi WSP saturated steam |
| Temperature Range | +10°F to 450°F |
| Cracking Pressure | 1/2 psi |
| Body Material | ASTM A351-CF8M (316 SS), investment cast |
| Seat | Soft PTFE — bubble-tight shutoff |
Dimensions
| Body Diameter | 1.35" |
| End-to-End Length | 2.31" |
| Weight | 0.40 lb |
Materials of Construction
| Body, Center Guide, Disc & End Cap | ASTM A351-CF8M (316 SS) |
| Spring | 316 SS |
| Seat & Gasket | PTFE |
Performance & Testing
- Low 1/2 psi cracking pressure — opens with minimal upstream pressure
- Spring-loaded for fast seating action; perfect seating at both high and low pressure
- Dual-guided stem and disc — stable, chatter-resistant operation
- High-capacity flow profile designed to minimize head loss
- 316/CF8M construction — excellent for chemicals and corrosive media
- Mounts in any orientation in horizontal or vertical lines (flow follows the body arrow)
Other Sizes in This Series
316 SS Inline Check Valve, 800 WOG, Female NPT (1/4"–2"). Jump to another size or add it straight to your cart:
| Size | Part # | Price | Cart |
| 1/4 in. | 949401 | $133.99 | Add to cart |
| 3/8 in. | 949402 | $130.99 | Add to cart |
| 1/2 in. (this page) | 949403 | $131.99 | — |
| 3/4 in. | 949404 | $202.99 | Add to cart |
| 1 in. | 949405 | $224.99 | Add to cart |
| 1-1/4 in. | 949406 | $401.99 | Add to cart |
| 1-1/2 in. | 949407 | $584.99 | Add to cart |
| 2 in. | 949408 | $915.99 | Add to cart |
Typical Applications
Backflow prevention on chemical feed and dosing lines, sodium hypochlorite and corrosive media systems, steam condensate lines, water and wastewater treatment, marine service, and pump discharge protection where brass or iron would corrode. The 1/2 psi cracking pressure suits low-head gravity and recirculation loops.
Cross-References & Interchange
Replacing another brand's 1/2 in. stainless inline check valve? Match nominal size, end connections, cracking pressure, and pressure rating for a direct fit — or send us your part number and we will confirm the interchange. Water or air service on a budget? The 1/2 in. brass inline check valve (944403) covers non-corrosive media for less.
Availability
In stock — ships direct from the manufacturer, typically 1–3 business days.