NCCER Millwright Practice Exam

What type of O-ring is suitable for temperatures between -300 and 500 degrees?

1. Neoprene

2. Silicone

3. Teflon

4. Fluorocarbon

The correct answer is: Teflon

Teflon, known for its chemical resistance and ability to withstand high temperatures, is an ideal choice for applications requiring an O-ring that can endure temperatures ranging from -300 to 500 degrees Fahrenheit. Teflon O-rings are particularly well-suited for extreme temperature variations due to their stable structure across a wide temperature range. In contrast, Neoprene has a much more limited temperature tolerance, generally effective in moderate temperature applications, and may not perform well at the extremes specified in the question. Silicone O-rings also maintain good performance over a range of temperatures, but they usually do not match the lower or upper extremes that Teflon handles. Fluorocarbon materials do provide good temperature resistance and chemical inertness, but Teflon surpasses them in handling the specified range effectively. Thus, Teflon emerges as the best option for applications demanding robust performance across such a wide and extreme temperature spectrum.