What is the purpose of a torque stripe/anti-seize lubricant on fasteners?

• A. To ensure accurate torque application and prevent galling or corrosion of threads.
• B. To make bolts harder to remove.
• C. To color-code fasteners for identification.
• D. To seal bolts against leaks.

Answer: (A)

Friction in the threads directly affects the clamping force you get from a given torque. An anti-seize lubricant reduces that friction, so the same indicated torque would normally produce a higher preload than with dry threads. To still reach the intended clamp load, the torque specification is adjusted for lubricated fasteners. The lubricant also helps prevent galling and corrosion, especially with dissimilar metals or in harsh environments, keeping threads healthy and easy to remove later.

A torque stripe adds a quick, visual check on installation: after torquing, you paint a line on the fastener so later inspections can see whether the fastener has moved or loosened. While the stripe itself is a separate monitoring tool, combining proper lubrication with the correct torque helps ensure the fastener reaches and retains the intended preload and remains protected from galling and corrosion.

The other options don’t fit: lubricants don’t make bolts harder to remove (they make removal easier), color-coding is not the primary purpose of lubrication or stripes, and sealing against leaks isn’t the main function of anti-seize on fasteners.