Spi 34-452-3 Threaded Pipe Ring 1-1/2 Npt Class L1

Product Description

The SPI 34-452-3 is a Class L1 threaded pipe ring gauge used to inspect and verify external NPT threads. Manufactured from tool steel, it provides the dimensional accuracy required for quality control and inspection work on threaded pipe connections. The 1-1/2-inch, 11-1/2 threads-per-inch NPT designation covers the standard taper pipe thread size common in plumbing, HVAC, and industrial piping applications. This gauge ships with NIST traceability certification, meeting the documentation requirements of quality management systems and regulated inspection environments. Metrology technicians and quality control professionals use this gauge to confirm that externally threaded pipe or fitting ends meet NPT tolerance standards before assembly.

This threaded pipe ring gauge is suited for inspection of 1-1/2-inch NPT external threads on pipe, fittings, and machined components in residential, commercial, and industrial settings. Typical applications include incoming inspection of threaded pipe stock, verification of machined fittings, and in-process quality checks during fabrication. The included NIST traceability certification supports compliance documentation in regulated manufacturing and utility environments.

Key Features

• Class L1 tolerance classification for standard NPT thread inspection
• 1-1/2-inch nominal size with 11-1/2 threads per inch NPT profile
• Tool steel construction for wear resistance and dimensional stability
• NIST traceability certification included for quality and compliance documentation
• Single-piece unit sold individually

Compatibility

Designed for inspection of 1-1/2-11-1/2 NPT external threads per Class L1 tolerance requirements. Compatible with any pipe, fitting, or component carrying a 1-1/2-inch nominal NPT thread profile.

Installation Notes

Threaded pipe ring gauges are handled and applied by metrology technicians or quality control inspectors, not installed in piping systems. Keep the gauge clean and free of chips, burrs, or thread compound before use to ensure accurate readings. Store in a protective case away from impact and temperature extremes to maintain calibration. Refer to ASME B1.20.1 for NPT thread tolerance standards when interpreting results.