To achieve a bolt of uniform strength, which action is appropriate?

• A. Increase shank diameter
• B. Increase its length
• C. Drill an axial hole through the head to equalize areas
• D. Tighten the bolt properly

Answer: (C)

Achieving a bolt of uniform strength involves ensuring that the distribution of stress is even across the entire bolt. When an axial hole is drilled through the head of the bolt, it can help to equalize the stress distribution and reduce the risk of failure due to concentrated stresses. This action can optimize the bolt's structural integrity by allowing stresses to dissipate more uniformly along the length of the bolt, thus preventing weak points that could lead to failure under load.

While increasing the shank diameter or length would influence the bolt's strength, it does not specifically address uniform strength throughout the bolt. Additionally, properly tightening the bolt is essential for ensuring that it performs its function effectively but does not fundamentally alter the inherent design or material strength characteristics that lead to uniform strength in the first place. Therefore, drilling an axial hole serves as a specific mechanical change to help even out the stress distribution, making it the appropriate action for achieving a bolt of uniform strength.