NPT / NPTF-ANPT / NGT Thread Gauges

NPT (National Pipe Thread) Gauges are supplied as Basic Step & Min/Max Step. Gauge dimensions are as per ASME B1.20.1. For Basic Step, while inserting the gauge manually onto the threads of the component, it should be flush with the end of the component face within 1 turn. Similarly, while inserting a Min/Max Step type gauge, the end of the component face should be flush between the Min and Max steps.

NPTF Threads, also known as Dryseal Threads, do not require a sealant to form a leak-proof joint. The thread crests and roots plastically deform during assembly to achieve a highly reliable seal without additional sealing compounds. They are designed for use on pipes, plugs, fittings, and similar devices in aeronautical components, chemical processing parts, and hydraulic components requiring a sealed thread joint where straight threads with gaskets or O-rings are inadequate.

NPTF Gauge dimensions are as per ANSI/ASME B1.20.5. NPTF Thread Plug Gauges are designed as L1 & L3 (Basic Step or Min/Max Step) and 6 Step Crest Check Plug. NPTF Thread Ring Gauges are designed as L1 & L2 (Basic Step or Min/Max Step) and 6 Step Crest Check Ring.

ANPT Threads (Aeronautical National Form Taper Pipe Thread) gauge dimensions are as per SAE AS71051B standard. ANPT Thread Plug Gauges are designed as L1 & L3 (Basic Step or Min/Max Step) and 6 Step Crest Check Plug. ANPT Thread Ring Gauges are designed as L1 & L2 (Basic Step or Min/Max Step) and 6 Step Crest Check Ring.

• NPTF & ANPT threads require additional gauging, as the truncation of these threads should be maintained within specified limits.
• L1 & L3 Plug Gauges and L1 & L2 Ring Gauges are used in combination to verify the size and taper of the component threads along the thread length.
• 6 Step Crest Check Plug and Ring Gauges are used to verify the crest diameter and truncation of the component threads along the thread length.
• Manufactured in hardened, precision hand-lapped OHNS Steel material to provide superior accuracy, excellent wear resistance, and optimum finish.
• Manufacturing Range: Dia. R 1/16″ to Dia. 10″.
• Subzero treated at -80°C for Dimensional Stability.
• Calibrated at 20°C under Standards Room conditions.
• Gauges are delivered in plastic case, providing anti-corrosion effect and impact resistance with Calibration Certificate (NABL/NPL Accredited).