Industrial seal self study guide - SKF.com

Chapter 7 Review
To take this test, simply place a card or sheet of paper under the first question.
After you’ve read it (and answered it to yourself) slide the paper down below the next
question. The correct answer to the first problem will appear directly to the right
of the new question. Be sure not to skip any questions.
1. To help ensure proper seal performance, the shaft _________________ .
❑ a. entrance edge should be chamfered or rounded
❑ b. surface finish should be 8-17 micro inch Ra (.20μm to .43μm)
❑ c. surface should have no machine lead
❑ d. all of the above
2. _________________ refers to the amount by which the shaft does not
rotate around the true center.
❑ a. Shaft-to-bore misalignment
❑ b. Dynamic run-out
❑ c. Shaft diameter
❑ d. none of the above
3. The recommended method for obtaining an optimum shaft finish is
_________________ .
❑ a. paper polishing
❑ b. roto preening
❑ c. plunge grinding
❑ d. diamond burnishing
4. Seals perform best on Rockwell C30 medium carbon steel
(SAE 1035, 1045) or _________________ .
❑ a. stainless steel
❑ b. aluminum
❑ c. bronze
❑ d. zinc
5. To assure a smooth sealing surface, the shaft should be ground with
_________________ rpm ratios.
❑ a. even number (2 to 1)
❑ b. odd number (3 to 1)
❑ c. mixed number (3.5 to 1)
❑ d. none of the above
1. D
2. B
3. C
4. A
5. C
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