Mitutoyo 345-351-30 Digimatic Inside Caliper Micrometer, Range 1 - 2" (25.4 - 50.8 mm)

Part No. 345-351-30 | Range 1–2" (25.4–50.8 mm) | Resolution .00005" / 0.001 mm | Accuracy ±.0003"

General Tech Services · Dammam, Saudi Arabia · +966 53 132 1586 · mathews@generaltechsaudi.com

Product Overview

The Mitutoyo 345-351-30 Series 345 Digimatic caliper-type inside micrometer is designed for measuring internal diameters, bores, internal grooves and slots from 1–2" (25.4–50.8 mm). Its caliper-type jaws enter the feature directly, allowing the measurement to be read on the integrated digital display.

The micrometer provides .00005" / 0.001 mm resolution and ±.0003" accuracy. Its carbide-tipped measuring faces are designed for repeated dimensional inspection, while the locking clamp holds the spindle position when the instrument needs to be withdrawn from a bore before reading or recording the measurement.

The Digimatic LCD provides a direct digital reading and supports functions including Origin setting, zero/ABS, data hold, function lock and inch/mm conversion. Digimatic SPC data output allows measurements to be transferred to compatible equipment such as a PC or data logger.

A setting ring or inside setting standard is required to establish the reference before measurement and is available separately. The micrometer is supplied in a protective case.

For smaller internal features, see the Mitutoyo 345-350-30, which covers .2–1.2" (5.1–30.5 mm).

Key Benefits

• Direct internal measurement: Caliper-type jaws measure bores, internal grooves and slots across 1–2".

• Fine digital resolution: .00005" / 0.001 mm resolution supports detailed dimensional inspection.

• ±.0003" accuracy: Suitable for precision measurement of internal features.

• Carbide measuring faces: Provide wear-resistant contact surfaces for routine inspection.

• Locking clamp: Holds the spindle position when withdrawing the instrument from a bore.

• Clear LCD display: Provides a direct digital measurement without interpreting an analog scale.

• Inch/metric capability: Supports measurement workflows using inch or metric units.

• Digital functions: Origin setting, zero/ABS, data hold and function lock support inspection workflows.

• SPC data output: Allows measurement values to be transferred to compatible data-collection equipment.

• Protective case: Helps protect the instrument during storage and transport.

For pricing and delivery availability of the 345-351-30, call +966 53 132 1586.

Who This Product Is Best For

The Mitutoyo 345-351-30 is suitable for CNC machining shops, quality-control departments, inspection laboratories, valve and fitting manufacturers, precision engineering facilities and maintenance teams.

It is particularly useful for inspectors measuring first-off parts, machinists checking internal dimensions between machining operations and maintenance engineers inspecting worn bores and components. The 1–2" range covers internal features from 25.4 to 50.8 mm, while the digital display and SPC output support electronic measurement records.

How to Use

1. Clean the measuring faces and the feature being measured.

2. Set the micrometer against a setting ring or inside standard of known size.

3. Use the Origin or zero-setting function to establish the measurement reference.

4. Close the jaws slightly below the expected feature size and insert them into the bore or groove.

5. Open the jaws gradually until both measuring faces contact the feature.

6. Rock the micrometer slightly to locate the maximum internal measurement where appropriate.

7. Lock the spindle with the clamp if the instrument needs to be withdrawn before reading.

8. Read the LCD display or transfer the measurement through the Digimatic SPC output.

Frequently Asked Questions

What is the Mitutoyo 345-351-30 used for?

The 345-351-30 is a Digimatic caliper-type inside micrometer for measuring internal diameters, bores, internal grooves and slots from 1–2" (25.4–50.8 mm).

How accurate is the Mitutoyo 345-351-30?

The 345-351-30 has a specified accuracy of ±.0003" and a resolution of .00005" / 0.001 mm, based on the supplied Series 345 catalogue data.

What type of measuring faces does the 345-351-30 have?

The micrometer uses carbide-tipped measuring faces. The caliper-type jaws are designed to enter internal features and contact the measuring surfaces directly.

Do I need a setting ring with the Mitutoyo 345-351-30?

Yes. An inside micrometer needs to be referenced against a known dimension before use. A suitable setting ring or inside setting standard is required and is available separately.

Does the 345-351-30 have SPC data output?

Yes. The Digimatic instrument provides data output for transferring measurement values to compatible equipment such as a PC or data logger.

What digital functions are available?

The supplied specifications identify Origin setting, zero/ABS, data hold, data output, function lock and inch/mm conversion.

Which Series 345 size should I choose?

Choose the model whose measuring range covers the internal feature you need to inspect. The 345-351-30 covers 1–2" (25.4–50.8 mm), while the 345-350-30 covers .2–1.2" (5.1–30.5 mm).

Is there an analog Mitutoyo inside micrometer for the same 1–2" range?

The supplied product information identifies the Mitutoyo 145-194 as an analog alternative covering the same general range. The 345-351-30 adds a digital display and Digimatic data output.

What is the difference between Mitutoyo 345-351-30 and 345-351-32?

The supplied source notes that distributor listings may identify the model as 345-351-32 and describe 345-351-30 as an earlier order-number designation. Because the exact order number can depend on the current Mitutoyo listing or supply channel, confirm the order number with General Tech Services before placing an order.

How do I buy the Mitutoyo 345-351-30 in Saudi Arabia?

Contact General Tech Services in Dammam for pricing and delivery availability. Call +966 53 132 1586 or email mathews@generaltechsaudi.com for a quotation.