What is the purpose of lubricants in worm gears?

• A. To increase friction between worm and worm wheel.
• B. To seal the gear housing.
• C. To reduce friction between worm and worm wheel, minimize wear, and control heat generation.
• D. To lubricate other components.

Answer: (C)

Lubricants in worm gear systems primarily create a protective film between the worm and the worm wheel. This film reduces sliding friction at the contact surfaces, which in turn lowers wear and minimizes surface damage like pitting or scoring. The sliding action in worm gear contacts generates a lot of heat, so the lubricant also helps carry away that heat to keep temperatures in a safe range. In addition, lubrication helps protect against corrosion and can help trap and carry away debris.

So the best choice is the one that describes reducing friction between the contacting surfaces, minimizing wear, and controlling heat generation. Increasing friction, sealing the housing, or merely lubricating other components don’t capture the main purpose in this context.