What is the primary purpose of a torque specification chart for bolts?

• A. To record part numbers
• B. To indicate recommended paint color
• C. To specify the correct torque to achieve required clamping force and joint integrity
• D. To schedule maintenance intervals

Answer: (C)

A torque specification chart guides you to apply the right amount of tightness to bolts to achieve the correct clamping force and keep the joint secure. It translates the needed clamping into a specific torque value for different bolt sizes and grades, taking into account factors like lubrication, thread pitch, and temperature. Following the chart helps ensure the joint stays tight enough to resist vibration and leaks, without over-tightening, which can stretch or strip bolts and damage parts. It’s not about part numbers, paint colors, or maintenance schedules—those are unrelated to achieving proper joint integrity.