Millwright Level 1 Practice Exam

Why should fasteners not be placed near welds when using a low velocity tool?

1. The steel may be too thick

2. The steel may have been hardened, making it brittle

3. The weld may not hold

4. It increases the risk of misfires

The correct answer is: The steel may have been hardened, making it brittle

The placement of fasteners near welds when using a low velocity tool should be approached with caution, particularly because welding can alter the properties of the surrounding material. In the case of a weld, the heat involved in the process can lead to hardening of the steel in the heat-affected zone (HAZ). When steel is hardened, it often becomes more brittle, which can significantly increase the likelihood of cracking or failure when subjected to stress or impact. Using a low velocity tool in this context can exacerbate the situation since these tools are designed to deliver fasteners with a specific amount of impact energy. If the material is brittle due to being hardened near the weld, there is a heightened risk of the fastener not achieving the necessary grip or integrity, possibly leading to joint failure. Therefore, the concern revolves around the mechanical properties of the steel being compromised by the welding process, necessitating careful consideration of fastener placement to avoid potential issues related to the brittleness of the material.