3/8 in. Aluminum Anti-Siphon Valve, Hose Barb x Male NPT
3/8 in. Aluminum Anti-Siphon Valve, Hose Barb x Male NPT
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The 3/8 in. Hose Barb x 1/4 in. Male NPT Aluminum Anti-Siphon Valve (#46531A) is an aluminum anti-siphon check valve that prevents backflow and siphoning in chemical metering and dosing lines. Hose-barb inlet and male NPT outlet allow direct connection to chemical tubing and pipe threads without additional adapters. Essential for maintaining pump prime and preventing chemical migration in dosing systems.
Technical Specifications
| Specification | Value |
|---|---|
| Body Material | Aluminum body |
| Spring Material | Stainless Steel |
| Seal / O-ring | Buna-N (NBR) |
| Pressure Rating | 150 PSI |
| Temperature Range | −20°F to 250°F (−29°C to 121°C) |
| Installation | Any orientation (vertical or horizontal) |
| Part Number | 46531A |
Key Features
- Aluminum body / Stainless spring construction
- Spring-loaded — closes automatically when flow stops or reverses
- Install in any orientation — vertical or horizontal
- Buna-N (NBR) seals — compatible with water, oils, and most process fluids
- Cracking pressure factory-set for reliable sealing
- Compact inline form factor — minimal installation space required
- Hose barb port for direct tubing connection
Common Applications
Used at the outlet of chemical metering pumps and injection points to prevent backflow, siphoning, and loss of pump prime. Aluminum body resists many chemical solutions used in water treatment and industrial dosing applications.
Technical Resources
- Check Valve Types: Swing, Spring, Wafer, Ball — Understand the differences
- How to Choose the Right Valve — Application selection guide
- Shop Brass Check Valves — Full brass check valve range
Expert Guides for This Product
- Check Valve Orientation & Installation — flow direction and mounting rules
- Check Valve Sizing Guide — why line size isn't valve size
- Slamming & Water Hammer — causes and fixes
- Check Valve Leaking? — diagnose and fix it
- Check Valve Chattering — the sizing problem nobody checks
- Buna vs. Viton Seats — which elastomer fits your media