Hayward® NVA Series needle valves are used for accurate metering of fluids. Each includes a built-in ball check valve with Hastelloy CTM spring to prevent back-flow of the process liquid into the chemical feed line. Turning the thumbwheel moves a tapered piston into the PTFE seat to control the flow down to a few drops per minute.
- PVC or glass-filled polypropylene
- PTFE seat
- Precision molded, fine pitched stem threads
- Permit this very fine metering flow control
- Flanges for panel mounting
- Maximum temperature: 150°F (PVC) & 260°F (PP)