A double back-to-back seal is classified as a(n) _____.

A double back-to-back seal is classified as a(n) _____.
 
  a. inside seal
  b. outside seal
  c. single sealing unit
  d. multiple sealing unit

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[Ques. 2] Fine to large cracks that radiate from the center of the seal ring outward indicate _____.
 
  a. incorrect seal composition
  b. mechanical failures
  c. heat checking
  d. improperly installed components

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[Ques. 3] Mechanical seals are classified by _____.
 
  a. size and configuration
  b. arrangement and design
  c. operating temperature and configuration
  d. industry and sector

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[Ques. 4] If the seal was not properly aligned or there is excessive wear in some bearing or shaft, _____ wear tracks will
  be the indicator.
 
  a. narrow
  b. radial
  c. parallel
  d. irregular

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[Ques. 5] Shaft packing and insert mounting, which includes O-rings, V-rings, wedges, and U-cups, describe the _____
  found in mechanical seals.
 
  a. lubricating surfaces
  b. closing mechanisms
  c. primary faces
  d. secondary seals