Mitutoyo 331-361-30 Electronic Spline Micrometer 1 in

Product Description

The MITUTOYO 331-361-30 is an electronic spline micrometer designed for measuring the diameter of splined shafts, bores, and other hard-to-reach internal features that standard anvil micrometers cannot access. It delivers a measurement accuracy of 0.0001 inch and a resolution of 0.00005 inch, making it suitable for precision inspection work in machining, manufacturing, and toolroom environments. The 1/4 inch spindle diameter and 0.18mm head diameter allow the instrument to reach into tight grooves and narrow spline roots. A ratchet stop thimble ensures consistent measuring force on every reading. The satin chrome finish reduces glare under shop lighting. Licensed machinists, quality control technicians, and toolroom professionals are the primary users.

This micrometer is built for precision dimensional inspection of splined components encountered in drive systems, gearboxes, and machined shaft assemblies. With a 1 inch measuring range and a 32mm throat depth, it handles a practical range of spline and groove geometries found in both prototype and production inspection settings. The data output port supports connection to a statistical process control system or data logger, making it well suited for documented inspection workflows in manufacturing quality programs. It ships with a plastic case for storage and field transport.

Key Features

• Accuracy of 0.0001 inch for high-precision dimensional inspection
• Resolution of 0.00005 inch (0.001mm) with 0.001 inch / 0.01mm graduation
• 1/4 inch spindle diameter with spherical anvil for spline root and groove access
• 32mm throat depth accommodates a range of shaft and component geometries
• Ratchet stop thimble delivers repeatable, consistent measuring force
• Data output port for SPC integration and electronic recordkeeping
• TUV certified; satin chrome finish; includes plastic storage case

Compatibility

Designed as an OEM-style precision measuring instrument for splined shaft and groove inspection applications requiring a 1 inch range electronic micrometer with a narrow-head spindle configuration.

Installation Notes

This instrument is used by metrology technicians, toolroom machinists, and quality control personnel. Before use, verify the micrometer is zeroed correctly per the manufacturer calibration procedure. Protect the measuring faces from impact and keep the instrument stored in its case when not in use. Do not apply excessive force beyond the ratchet stop, as overloading the spindle can affect calibration and accuracy.