Millwright Level 1 Practice Exam

The primary function of a knurled surface on a gauge is to improve grip. When a surface is knurled, it is made rough by creating a patterned texture, which significantly increases friction. This texture allows users to hold and manipulate the gauge more securely, even in situations where their hands might be oily or wet. As a result, operators can achieve a more accurate reading by preventing slips that could occur if the gauge were smooth.

While options such as increasing accuracy and enhancing durability may have relevance in different contexts, they do not directly relate to the primary purpose of a knurled surface. A knurled finish does not intrinsically make the gauge more accurate; rather, it facilitates better handling which could indirectly support accuracy. Similarly, while a knurled surface might contribute to the overall usability and longevity of a gauge, such as resisting wear under frequent handling, the most critical purpose remains its role in improving grip.