Intro to Millwright Practice Exam

Which of the following types of drill bits is known for durability and heat resistance?

1. Cobalt Drill Bit

2. Diamond Drill Bit

3. Wood Drill Bit

4. Ceramic Drill Bit

The correct answer is: Cobalt Drill Bit

Cobalt drill bits are specifically designed to withstand high temperatures and provide exceptional durability. This is due to the high cobalt content in their alloy, which enhances their hardness and allows them to maintain sharpness longer than standard high-speed steel drill bits. They are particularly useful for drilling into tough materials, such as stainless steel and other alloys, where the heat generated during drilling can be significant. Their ability to resist wear and heat makes them an ideal choice for heavy-duty applications. In contrast, diamond drill bits are highly effective for cutting through hard materials like concrete or stone but may not exhibit the same level of heat resistance as cobalt bits when used on metals. Wood drill bits are designed specifically for drilling into wood, and their structure is not suited for durability in tougher materials. Ceramic drill bits are typically used for specialized tasks and are not primarily known for their heat resistance or durability in metalworking applications.