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Telescopic Gauge

 A telescopic gauge, also known as a telescoping gauge or a bore gauge, is a precision measuring instrument used to measure the internal diameter of a hole or bore. It consists of two or three spring-loaded arms that can be extended and retracted by twisting a knurled handle or turning a locking nut.

The main purpose of a telescopic gauge is to accurately determine the size of a hole, ensuring proper fitment of mating components or verifying compliance with specified tolerances. It is commonly used in machining, manufacturing, engineering, and other industries where precise measurements are crucial.

The design of a telescopic gauge allows for easy insertion into a hole. When the handle or nut is twisted, the arms expand outward, making contact with the inner walls of the bore. The gauge is then carefully withdrawn from the hole, maintaining the expanded position. The measurement is taken by using an external measuring device, such as a micrometer or caliper, to measure the distance between the two arms.

Telescopic gauges typically have a measuring range of several millimeters to several inches, depending on the specific model. They are available in various sizes and configurations to accommodate different bore diameters and shapes, including cylindrical, conical, and even irregular shapes.

To ensure accurate and reliable measurements, telescopic gauges are manufactured with high precision and made from materials with low thermal expansion, such as hardened steel or alloy. The spring-loaded arms are designed to maintain a consistent pressure against the walls of the bore, minimizing any deformation that could affect the measurement.

When using a telescopic gauge, it is important to handle it with care to prevent damage to the gauge or the bore being measured. Proper technique involves inserting the gauge perpendicular to the bore, avoiding any lateral force that could introduce errors. Regular calibration and maintenance are also essential to ensure the gauge remains accurate and in good working condition.

In summary, telescopic gauges are versatile and reliable instruments used for measuring the internal diameter of bores. Their ability to provide precise measurements makes them invaluable tools in various industries where dimensional accuracy is critical for proper functioning and fitment of components.