Millwright Level 1 Practice Exam

Which of the following tools is specifically designed for reading the depth of holes?

1. Caliper

2. Depth micrometer

3. Ruler

4. Micrometer screw gauge

The correct answer is: Depth micrometer

The depth micrometer is specifically designed to measure the depth of holes with precision. This tool features a cylindrical rod that extends into the hole, allowing the user to obtain accurate depth measurements. The main advantage of using a depth micrometer is that it provides a higher degree of accuracy than other measuring tools, making it ideal for applications where precision is critical. While calipers can measure a variety of dimensions—like internal and external distances—they are not specifically tailored for measuring depths and may not provide the same level of accuracy as a depth micrometer in this context. A ruler, although useful for general measurements, lacks the precise scaling required for depth measurement, especially in tighter or more intricate environments. Similarly, a micrometer screw gauge is primarily used for measuring the thickness or outside dimensions of objects rather than depths, limiting its applicability for this specific purpose. Thus, the depth micrometer stands out as the most appropriate choice for accurately determining hole depths, making it the correct answer.