Spi 30-640-7 Inside Dial Caliper Gage 0.93-8 in

Product Description

The SPI 30-640-7 is an inside dial caliper gage designed for precise internal measurement of bores, holes, and grooves. It covers a measurement range of 0.93 to 8 inches with a fine graduation of 0.0005 inches, making it suitable for high-accuracy inspection work in machine shops, HVAC fabrication environments, and mechanical service applications. The tool uses ball contact points for consistent seating against curved interior surfaces, reducing measurement error in cylindrical bores. Machinists, pipefitters, and mechanical technicians rely on this type of instrument for verifying internal dimensions to close tolerance during fabrication, installation, or quality control checks.

This inside dial caliper gage is used wherever internal bore or hole dimensions must be confirmed to tight tolerances. Typical applications include verifying pipe bore diameter, checking machined housing fits, and inspecting cylindrical components during assembly or maintenance. The 0.93-inch minimum range allows measurement of relatively small bores, while the 8-inch maximum accommodates larger pipe and housing diameters common in industrial and commercial mechanical work.

Key Features

• Measurement range of 0.93 to 8 inches covers a wide variety of bore sizes
• 0.0005 inch graduation for fine, high-accuracy readings
• Ball contact points included for accurate seating in cylindrical and curved internal surfaces
• Dial indicator readout allows quick, direct measurement without calculation
• Suitable for quality control, fabrication inspection, and mechanical service tasks

Compatibility

Designed as a general-purpose inside dial caliper gage for use in machine shop, industrial, and mechanical service environments where internal bore measurements from 0.93 to 8 inches are required.

Installation Notes

This is a precision measurement instrument, not a fixed installation component. Handle with care to avoid dropping or impacts that can affect calibration accuracy. Zero the dial indicator against a known reference standard before use. Store in its protective case when not in use to prevent damage to the contact points and dial mechanism.