Millwright Level 1 Practice Exam

What is one method to remove a broken high-speed steel hand tap from a hole?

1. Use a hammer

2. Utilize an electrical discharge machine

3. Apply heat to the area

4. Use a welding tool

The correct answer is: Utilize an electrical discharge machine

Utilizing an electrical discharge machine is a highly effective method for removing a broken high-speed steel hand tap. This technique involves creating sparks between a conductive electrode and the workpiece, which erodes the broken tap without damaging the surrounding material. The precision of electrical discharge machining makes it particularly suitable for delicate operations where surrounding components must remain intact. In contrast, other methods would not achieve the same level of effectiveness or could cause additional complications. For example, applying heat might warp the surrounding material or weaken the integrity of the workpiece. Using a hammer could result in further embedding the broken tap or fracturing it into smaller, more difficult-to-remove pieces. Meanwhile, a welding tool could risk creating a solid bond with the broken tap, complicating its removal even further.