Spi 23-120-9 Truncated Taperlock Thread Plug Gage 2-56 Unc

Product Description

The SPI 23-120-9 is a truncated taperlock thread plug gage used to inspect 2-56 UNC internal threads for conformance to Class 2A tolerance standards. It includes both Go and No Go members, allowing a technician or inspector to verify that a threaded hole is within the acceptable pitch diameter range in a single tool set. The gage is machined from tool steel for dimensional stability and wear resistance. With a 2.25-inch body length and a lightweight profile at 0.026 pounds, it is suited for bench inspection and in-process quality control in precision machining and assembly environments.

This gage is intended for use in manufacturing, machining, and assembly operations where small-diameter unified coarse thread fasteners are used. The 2-56 UNC thread form is common in instrument manufacturing, electronics hardware, and precision mechanical assemblies. The truncated taperlock design allows for efficient gage member replacement without replacing the full handle. Quality control inspectors, machinists, and assembly technicians use this type of gage to confirm thread acceptability before components advance in the production process.

Key Features

• Go and No Go members included for full Class 2A pitch diameter verification
• Truncated taperlock design allows gage member replacement while reusing the handle
• Tool steel construction provides hardness and dimensional stability under repeated use
• Covers 2-56 UNC thread specification for small-diameter coarse thread inspection
• Lightweight at 0.026 pounds, suitable for handheld bench inspection use

Compatibility

Designed for inspection of 2-56 UNC internal threads to Class 2A tolerance requirements. Suitable for use with standard taperlock-style gage handles that accept truncated gage members.

Installation Notes

Thread plug gages are inspection tools and do not require installation in the traditional sense. Insert the Go member by hand into the threaded hole being inspected — it should pass through without force. The No Go member should not enter the thread. Never force either member, as this can damage the gage or the workpiece. Gages should be periodically recalibrated or replaced in accordance with your facility quality system and applicable ASME B1.2 standards.