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Throttle Master Needle Valves: Precise Flow Control for Corrosive and High-Purity Fluids

Marquest Scientific Throttle Master Needle Valves, available in PVC, CPVC, Polypropylene, and PVDF materials, are designed to provide precise flow control and fine adjustment when handling corrosive and high-purity fluids in various applications. These valves are produced in two styles: globe pattern (straight 180°) and angle pattern (90°), offering excellent performance and durability.

Key features:

  • Needle finish (SPI/SPE No. 1) for bubble-tight, low-torque shutoff and long-term performance
  • All injection molded components for a rugged design and construction
  • 24 Pitch metering thread for 20% finer metering control and excellent linearity of flow
  • PTFE-sealed needle stem for excellent chemical resistance and high purity
  • Integrally designed panel mounting, accommodating panel thicknesses from 1/16" to 1/2" without fasteners
  • No elastomers (O-Rings), metals, or lubricants, eliminating corrosion and contamination risks

Note: End connections for the Throttle Master Needle Valves include 1/4", 3/8", and 1/2" Female NPT, as well as solvent socket "slip" connections. Tube connections are also available.

Maximum pressure ratings vary by material:

  • PVC: 180 PSI @ 72° Fahrenheit
  • CPVC: 200 PSI @ 72° Fahrenheit
  • Polypropylene: 150 PSI @ 72° Fahrenheit
  • PVDF: 220 PSI @ 72° Fahrenheit

The valve body and components are injection molded using high-quality materials, including PVC, glass and mineral reinforced Polypropylene, CPVC, and high-purity PVDF. These materials meet and/or exceed FDA, USDA, and USP standards. The stem seal is machined from 100% virgin PTFE (Polytetrafluoroethylene) for superior sealing performance.

For additional specifications and downloads, including data sheets, click on the item numbers below.

Product Image
Unit of Measure
Items NG-250-PVC
NG-250-PVC
1/4" x 1/4" Female NPT Globe (Straight Pattern) Needle Valve-PVC
List Price $64.50
NA-250-PVC
NA-250-PVC
1/4" x 1/4" Female NPT Angle Needle Valve-PVC
List Price $64.50
NG_375_PVC 2
NG-375-PVC
3/8" x 3/8" Female NPT Globe (Straight Pattern) Needle Valve-PVC
List Price $64.50
NA-375-PVC
NA-375-PVC
3/8" x 3/8" Female NPT Angle Needle Valve-PVC
List Price $64.50
NG-500-PVC
NG-500-PVC
1/2" x 1/2" Female NPT Globe (Straight Pattern) Needle Valve-PVC
List Price $72.95
Materials N/A PVC, PTFE Seal
Inlet x Outlet N/A 1/4" Female NPT N/A 1/4" Female NPT N/A 3/8" Female NPT N/A 3/8" Female NPT N/A 1/2" Female NPT
Style N/A Globe, Straight Pattern N/A Angle, 90° Pattern N/A Globe, Straight Pattern N/A Angle, 90° Pattern N/A Globe, Straight Pattern
Cv Factor N/A 0.310 N/A 0.426 N/A 0.310 N/A 0.426 N/A 0.620
Materials of Construction N/A

PVC Body, PTFE Seals

N/A N/A N/A N/A
Specifications N/A