Machinery Lubrication magazine published by Noria Corporation
Issue link: http://www.e-digitaleditions.com/i/655822
THIS MONTH, MACHINERY LUBRICATION CONTINUES ITS "TEST YOUR KNOWLEDGE" SECTION in which we focus on a group of questions from Noria's Practice Exam for Level I Machine Lubrication Technician and Machine Lubricant Analyst. The answers are located at the bottom of this page. The complete 126-question practice test with expanded answers is available at store.noria.com. TEST YOUR KNOWLEDGE Answers 1. D Viscosity is a function of temperature. The change in an oil's viscosity with respect to temperature is represented by the oil's viscosity index (VI), which is unitless. It can be experimentally calculated by determining the viscosity at 40 and 100 degrees C. 2. C A single-point grease lubricator is used to pump grease to a limited number of grease points (normally one). It should be inspected regularly to ensure it is functioning properly. These types of lubricators are very useful for hard-to-reach lube points, enhancing safety and reliability. The pressure produced by single-point lubricators is much less than centralized greasing systems, so the correct answer is C. 3. B As oil ages, a series of chemical reactions takes place within the oil. This normally results in many chemical species, including acids. The formation of these acids causes the acid number to increase. 1. Viscosity index is: A) An instrument to measure viscosity B) A unit of viscosity C) An oil's change in viscosity with pressure D) Relates to the relative change in viscosity to change in temperature E) An oil's change in viscosity with shear 2. Single-point grease lubricators: A) Are able to pump grease to a large number of grease points B) Are a reliable "set it and forget it" grease-dispensing system C) Are useful for hard-to-reach lube points D) Are capable of producing pressures similar to centralized systems E) All of the above 3. After some possible initial change, as oil ages, the acid number generally: A) Trends down B) Trends up C) Stays very flat D) Oscillates both up and down E) None of the above Twiter Stay Connected With Noria Follow us on Twitter https://twitter.com/NoriaCorp Like us on Facebook http://www.facebook.com/noriacorp Connect with us on LinkedIn https://www.linkedin.com/company /noria-corporation Continue learning with us on YouTube http://www.youtube.com/user/noriacorp www.machinerylubrication.com | March - April 2016 | 35