Spi 34-501-7 Threaded Ring Gage M18 X 2.50 Class 6G Go

Product Description

The SPI 34-501-7 is a single-ring threaded ring gage designed to verify external thread conformance on M18 x 2.50 metric fasteners and threaded components to Class 6G tolerance. This is a Go-type gage, meaning it checks that a threaded workpiece falls within the maximum material condition limit — the part must pass through the Go ring to be accepted. Machined from oil-hardened non-shrinking tool steel (OHNS), the gage delivers the dimensional stability and wear resistance required for production inspection and quality control environments. An NPL Traceability Certification is included, supporting documented calibration programs.

This gage is used in manufacturing, machine shop, and quality assurance settings where metric external threads must be verified to ISO and ANSI tolerance standards. Typical applications include inspection of bolts, studs, shafts, and threaded rod in Class 6G metric thread specifications. It is appropriate for both incoming inspection of purchased hardware and in-process verification during CNC or manual threading operations. Machinists, quality technicians, and tool crib personnel are the primary users.

Key Features

• Go-type ring gage confirms external threads meet maximum material condition for Class 6G fit
• M18 x 2.50 metric thread specification for standard coarse-pitch fastener inspection
• Oil-hardened non-shrinking steel (OHNS) construction for dimensional stability and long service life
• Single-ring design for straightforward Go verification without No-Go in the same body
• NPL Traceability Certification included for use in calibrated quality systems

Compatibility

Designed for inspection of external metric threads sized M18 x 2.50 to Class 6G tolerance. Suitable for use wherever Go-type thread verification is required on standard coarse-pitch metric fasteners and threaded components.

Installation Notes

Threaded ring gages are hand-inspection tools and require no installation. Handle with clean, dry or lightly oiled hands to prevent corrosion on the precision ground surfaces. Store in the provided case or a protected tool crib location away from impact and temperature extremes. Calibration intervals should follow your shop quality plan; NPL traceability documentation supports ISO 9001 and similar quality management programs.