Mitutoyo 146-231CAL Groove Micrometer Calibrated

Product Description

The MITUTOYO 146-231CAL is a mechanical groove micrometer designed for precision inside and outside diameter measurements in confined groove and channel geometries. It covers an inside measurement range of 0.055 to 1.5 inches and an outside measurement range of 0 to 1 inch, with an accuracy rating of 0.0004 inches. The tool ships calibrated to NIST traceability standards, making it ready for use in quality-controlled environments. A two-directional ratchet stop thimble provides consistent measuring force, reducing operator-induced error. The satin chrome finish resists glare and corrosion under shop conditions. Machinists, tool-and-die technicians, and metrology personnel are the primary users of this instrument.

This groove micrometer is suited for measuring internal grooves, slots, and recesses where standard inside micrometers cannot reach, as well as outside diameters in restricted-access areas. Typical applications include checking snap ring grooves, retaining ring grooves, bearing seats, and similar features on turned or machined components. The 5 mm spindle diameter and 35 mm reach length allow access into narrow groove profiles. It is appropriate for both production-floor spot checks and inspection-room measurement tasks.

Key Features

• Inside measurement range: 0.055 to 1.5 inches for groove and slot work
• Outside measurement range: 0 to 1 inch
• Accuracy of 0.0004 inches for precise dimensional verification
• Two-directional ratchet stop thimble for repeatable, consistent measuring force
• Calibrated with NIST traceability certification included at time of shipment
• 5 mm spindle diameter and 35 mm reach length for narrow-groove access
• Satin chrome finish reduces glare and provides corrosion resistance

Compatibility

Designed as an OEM-style precision measuring instrument for use in general machining, inspection, and quality control applications where groove and slot inside diameter measurement is required.

Installation Notes

This instrument requires no installation in the traditional sense but should be handled and stored according to standard metrology practices. Keep the measuring faces clean and free of chips, coolant, and debris before and after each use. Store in the supplied case with the key to protect the calibrated surfaces. Calibration status should be verified against a known standard before use in any quality-critical measurement task, in accordance with applicable shop quality management procedures.