Seal 101 Quiz

Have some fun and take the Seal 101 Quiz. No matter how you score, your prize will be a greater knowledge of seals and sealing devices. Remember, you can find these and other answers to your sealing questions on Apple Rubber's website and in our Seal Design Guide. Good luck.

  • Why are most sealing grooves wider than they are deep?
    • Ease of machining
    • Space constraints
    • Necessary to provide adequate compression while allowing room for the seal to "flow" into
    • To allow for any type of seal profile
  • Is designing around a non-standard O-ring fundamentally different than a standard O-ring?
    • Yes
    • No
  • Which elastomer can seal both acids and bases relatively well?
    • Silicone
    • Ethylene-Propylene
    • Neoprene
    • Butyl
  • Which lubricant should never be used when employing a silicone O-ring?
    • Silicone grease
    • DC 55
    • Soap solution
    • Petroleum based grease
  • Which elastomeric compound has the best abrasion resistance properties?
    • Silicone
    • Ethylene-Propylene
    • Fluorosilicone
    • Carboxilated nitrile
  • Which condition has the least impact on nitrile?
    • MEK
    • Ozone
    • 300°F
    • Keytones
  • Why are dynamic O-rings compressed less than static O-rings?
    • Dynamic O-rings cannot handle increased compression
    • Space limitations within the groove
    • Less friction is developed which extends seal life
    • Surface finishes are typically better on dynamic systems; therefore less compression is needed
  • Why are O-rings round in profile?
    • Ease of installation
    • Symmetrical
    • Bi-directional sealing
    • All of the above
  • What types of changes occur in O-rings at elevated temperatures?
    • Same as cold temperatures
    • Physical and reversible
    • Chemical and irreversible
    • None of the above
  • If an O-ring gland is too small for a given O-ring, what will happen?
    • Premature seal failure
    • Shearing and nibbling
    • Stress cracks begin to develop
    • All of the above
  • When designing a seal for a rotary application, should there be any ID stretch (as seen in oscillating and reciprocating seals)?
    • Yes
    • No
  • If a lack of compression is suspected as a reason for seal failure, what would correct the problem?
    • Decrease bore diameter
    • Increase groove diameter
    • Decreases seal durometer
    • All of the above
  • Why are there tolerances for O-rings?
    • To allow for English/Metric conversion
    • To account for rubber's physical properties and inevitable variations
    • To allow for relaxed manufacturing practices
    • To match the tolerances of surrounding media (plastic, metal, etc.)
  • Why are most O-rings black?
    • Supplier demand
    • Use of carbon black in compounding
    • Vibrant colored O-rings require much more control and are more costly
    • All of the above
  • Why are O-rings so widely used?
    • Can function beyond "seals" (bumpers, drive belts, etc.)
    • Can seal very small places
    • Economical for replacement
    • All of the above



  
 
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1.800.828.7745 (US and Canada Only)