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- Snap gauges
Snap gauges, also known as ring gauges, are precision measurement tools used to verify the outside diameter
of cylindrical parts. They consist of two anvils or jaws—one fixed and one movable—that are brought together to
measure the diameter of the part being inspected.
Snap gauges are typically designed to be adjustable to accommodate a range of part diameters within a specified
tolerance. The movable jaw can be adjusted using a screw mechanism or a spring-loaded mechanism, allowing
it to be set to the desired diameter.
To use a snap gauge, the part being measured is placed between the anvils, and the movable jaw is closed until it
makes contact with the part. If the part’s diameter falls within the acceptable tolerance range, the anvils will “snap”
into place around the part, indicating that the part is within spec. If the part’s diameter is too large or too small, the
anvils will not close properly, indicating that the part is out of tolerance.
Snap gauges are commonly used in manufacturing and quality control processes to quickly and accurately
measure the diameter of cylindrical parts, ensuring that they meet the required specifications.
Safety Precaution of gauges
1 Handle with Care*: Gauges are precision instruments and should be handled gently to avoid damage to their
delicate components.
2 Keep Clean*: Ensure that gauges are free from dirt, debris, and oil, as these can affect measurements. Clean
gauges regularly with a soft cloth or brush.

3 Store Properly*: Store gauges in a clean, dry environment to prevent corrosion and damage. Avoid storing
them in areas with extreme temperatures or humidity.

Ball & Roller gauges and their uses

Features:
1 Ball Gauges:
Description:
• Ball gauges consist of precision spherical balls made from materials like tungsten carbide, ceramic, or hardened
steel.
• These balls are manufactured with extremely accurate and consistent diameters.
Uses:
• Measurement Verification: Ball gauges are utilized to verify the diameter of cylindrical holes or bores. By
inserting the ball into the hole, the user can determine if the diameter is within specified tolerances. A proper
fit without play indicates that the hole meets the required diameter.
• Go/No-Go Gauging: They are commonly employed as Go/No-Go gauges for quick assessment of whether a
hole’s diameter meets specific tolerances. A ball gauge with a known diameter serves as the Go gauge, while
a slightly larger one acts as the No-Go gauge.
2 Roller Gauges:
Description:

• Roller gauges consist of precision cylindrical rollers made from materials such as carbide, ceramic, or hardened
steel.
• These rollers are precisely machined to have consistent diameters along their length.

Uses:
• Measurement Verification: Roller gauges are employed to verify the diameter and roundness of cylindrical
components like shafts and pins. By rolling the gauge along the length of the component and measuring at
various points, dimensional consistency can be assessed.

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