Mitutoyo 293-244-30 IP65 0-25mm Digital Micrometer

Technical Overview

Digital outside micrometer featuring a 0-25mm range, 0.001mm resolution, ±1µm accuracy, IP65 coolant-proof rating, and constant-force ratchet thimble.

Key Features

Measuring range of 0 to 25 mm with a high-precision digital step resolution of 0.001 mm
Exceptional instrument accuracy of ±1 µm and parallelism of 1 µm
IP65 protection rating ensures high resistance to dust, water jets, and cutting oil splashes
Ratchet thimble mechanism provides a constant measuring force of 7 to 12 N for repeatable accuracy
Crafted with oil-resistant materials for all plastic components to prevent physical deterioration
Ergonomic, non-slip frame cover with raised dots ensures stable handheld operation
Long battery life of approximately 2.4 years under normal operation on a single SR44 battery
Built-in Hold function freezes the displayed value for convenient off-workpiece reading
Auto-power off function after 20 minutes of non-use to preserve battery life
Function lock prevents accidental resetting of origin-set or zero-set points

Technical Specification Matrix

Parameter	Value
Measuring Range	0 - 25 mm
Resolution / Digital Step	0.001 mm
Accuracy	±1 µm
Flatness	0.3 µm
Parallelism	1 µm
IP Protection Rating	IP65
Measuring Force	7 - 12 N
Spindle Pitch	0.5 mm
Measuring Spindle Diameter	6.35 mm
Battery Type	SR44 (Silver Oxide)
Battery Life	Approx. 2.4 years under normal use
Data Output	None (No SPC)
Thimble Type	Ratchet Thimble
Numeral Height	7.5 mm
Physical Weight (kg)	0.28
Dimensions L x W x H (cm)	14.75 x 1.8 x 6

Industrial Applications

1. Precision Quality Control in Metal Machining Workshops

In metal machining workshops, workpieces such as precision pins, shafts, and automotive engine parts are machined down to tight tolerances. Machinists can use this micrometer directly on the shop floor to measure workpiece dimensions.

Problem Solved

Cutting fluid, lubricating oil, and metal dust can easily destroy normal electronic measuring tools or cause reading drift. The IP65 rating and oil-resistant plastic construction of the 293-244-30 allow machinists to perform highly accurate measurements (±1 µm accuracy) directly inside CNC enclosures or next to lathes without wiping parts completely dry, reducing inspection cycle times.

CNC MachiningOutside Diameter MeasurementCutting Fluid ResistanceIP65 Rating±1 µm Accuracy

2. Automotive Component Stamping and Thickness Auditing

Stamping facilities require frequent verification of sheet metal and component thicknesses to ensure structural integrity and compliance with design tolerances.

Problem Solved

Variations in clamping force can lead to measurement inconsistencies among different operators. The 293-244-30 utilizes a ratchet thimble that provides a constant measuring force of 7–12 N. This ensures highly repeatable, operator-independent measurements of stamped parts on the factory floor, preventing false rejects or accepting out-of-spec products.

Thickness VerificationRepeatable Clamping ForceRatchet ThimbleSheet Metal StampingTolerancing

3. Hydraulic Valve Spool Precision Grinding

Hydraulic systems operate at high pressures and require extremely tight clearances between valve spools and bodies. During the spool grinding process, diameters must be monitored down to the micrometer level.

Problem Solved

Thermal expansion from holding the micrometer can introduce measurement errors. The 293-244-30 features a highly stable frame with a built-in heat shield that minimizes heat transfer from the operator's hands. Combined with the micro-lapped carbide-tipped measuring faces, it prevents thermal drift and wear, ensuring the valve spools are ground exactly to within the ±1 µm tolerance limit.

Hydraulic ValvesValve Spool GrindingThermal Expansion PreventionCarbide-Tipped AnvilsPrecision Metrology