Mitutoyo 137-220 Inside Micrometer 2 to 60 Inch

Product Description

The MITUTOYO 137-220 is a mechanical inside micrometer designed to measure internal diameters and bore sizes across a wide range of 2 to 60 inches. It uses an extension rod configuration, allowing technicians to reach deep into bores and large-diameter openings without switching tools. The instrument reads in decimal inches with a gage depth of 0.5 inches, making it appropriate for precise internal measurement tasks in manufacturing, maintenance, and mechanical inspection environments. This tool is installed and operated by machinists, metrologists, and precision maintenance technicians who require repeatable bore measurements without electronic components.

The 137-220 is suited for shop floor and field applications where large internal diameters must be measured accurately. Its extension rod design covers bore sizes from 2 to 60 inches, making it applicable to large-bore cylinder inspection, housing alignment checks, and industrial equipment maintenance. The mechanical design requires no batteries or digital readout system, which is an advantage in environments where electronic instruments may be impractical. This micrometer is a fit for machine shops, heavy equipment service operations, and industrial maintenance programs.

Key Features

• Wide measurement range of 2 to 60 inches via extension rod system
• Extension rod type configuration for deep bore and large-diameter access
• Gage depth of 0.5 inches for consistent contact measurement
• Fully mechanical operation with no digital counter or battery requirement
• Decimal inch readout for direct compatibility with standard engineering drawings

Compatibility

Designed as an OEM-style mechanical inside micrometer for general industrial and precision measurement applications requiring internal diameter measurement from 2 to 60 inches.

Installation Notes

This instrument is used by machinists and precision measurement technicians and does not require installation in the traditional sense. Before use, verify that the contact points and extension rods are clean and free of debris, as contamination will affect reading accuracy. Store the micrometer in its case when not in use to protect the spindle and measuring faces. Calibration against a known standard is recommended before critical measurement work, though this unit is not factory-calibrated at time of shipment.