Spi 37-171-6 Plug Thread Gage M30x3.5 6H No Go

Product Description

The SPI 37-171-6 is a single-end No Go plug thread gage designed to verify that an M30x3.5 internal thread does not exceed maximum material condition limits. Built to 6H tolerance class, it provides a straightforward pass/fail check for threaded holes in production and inspection environments. The gage is used without a handle, which is sold separately, and carries ANSI traceability certification traceable to NIST standards. Metrology technicians, quality control inspectors, and precision machinists rely on this type of gage to catch oversized or out-of-tolerance threads before components move forward in assembly.

This gage is suited for dimensional inspection of M30x3.5 threaded bores in manufacturing, job shop, and quality lab settings. It is appropriate for both incoming inspection of purchased components and in-process verification during machining operations. The single-end No Go configuration makes it a focused tool for confirming that a thread has not been cut beyond the allowable upper limit, complementing a corresponding Go gage in a complete thread inspection routine.

Key Features

• No Go plug gage checks that M30x3.5 internal threads do not exceed maximum material condition
• 6H tolerance class meets standard commercial and precision fastener thread requirements
• ANSI traceability certification included, traceable to NIST
• Single-end design for dedicated No Go inspection without a double-end tool
• Handle not included, allowing use with a separately sourced handle that fits the application

Compatibility

Designed for inspection of M30x3.5 internal threads classified to 6H tolerance. Intended for use with a compatible thread gage handle, sold separately.

Installation Notes

Thread plug gages are handled by quality control inspectors and metrology personnel, not field tradespeople. Before use, ensure the gage and workpiece threads are clean and free of chips, coolant, and debris. Never force the No Go gage into a thread; it should not enter a conforming thread, and forcing it can damage both the gage and the part. Store the gage in its protective case when not in use to preserve calibration and surface condition.