Millwright - Power Transmission Questions & Answers 100% Correct, Exams of Mechatronics

Download Millwright - Power Transmission Questions & Answers 100% Correct and more Exams Mechatronics in PDF only on Docsity! Millwright - Power Transmission Questions & Answers 100% Correct 1. Calculate the accurate belt length for the following: Large diameter pulley is 11.25" and the small diameter pulley is 6.125". Shaft centers are 17.5" apart. a. 62.65" b. 62.00" c. 73.98" d. 62.28" - ANSWER-a. 62.65" L=2C+1.57(D1+d2)+[(D1-d2)²/4C] L=2(17.5)+1.57(11.25+6.125)+[(11.25-6.125)²/4(17.5)] L=35+27.27875+(26.265625/70) L=62.65 2. The clearance of meshing gears of any diametral pitch is known as: a. Back lash b. Tolerance c. Dedendum d. Addendum - ANSWER-a. Back lash 3. A Babbitt bearing percentage refers to its area of contact. This is found by: a. Feeler gauges b. Plastic gauge c. Bluing d. Lead wire - ANSWER-c. Bluing 4. A bearing with a "K" it denotes a tapered bearing. This is held in place by: a. Shaft collar b. A tapered adapter sleeve c. Lock nut d. Thread locker - ANSWER-b. A tapered adapter sleeve 5. An 8" pulley turns at 120 RPM and drives a second pulley at 150 RPM. What is the driven pulley diameter? a. 4.6" b. 6.4" c. 8.3" d. 3.8" - ANSWER-b. 6.4" 120RPM/150RPM = 0.8 ratio 0.8 x 8" = 6.4" 6. The letters A, B, C on a sprocket refers to: a. Tooth size b. Pitch c. Hub Class d. Type of chain - ANSWER-c. Hub Class 7. Crowning on a pulley is used for: a. Decreased wear b. Tension c. Self alignment d. To allow for different classes of belts - ANSWER-c. Self alignment 8. The standard taper on an imperial key is: a. 1:100 b. 1:96 c. 1:4 d. 1:25 - ANSWER-b. 1:96 9. A type of bearing mounted face to face and back-to-back is: a. Angular contact b. Conrad c. Ball d. Pillow Block - ANSWER-a. Angular contact 10. A bearing with a code of SKF 6212 has a bore of: a. 12mm b. 1⁄2" c. 60mm d. 62mm - ANSWER-c. 60mm 11. A belt is wrapped around a 6.25" pulley and has 220 degrees of contact. How much of the belt is contacting the pulley? (Use 3.14159 for pi) a. 12" a. The design b. The use of non synthetics c. Elasticity d. Worn motor bearings - ANSWER-c. Elasticity 22. What is "creep" in a bearing? a. The very slow rotation of the outer race b. The movement of the bearing as it rotates out of the housing c. A condition that allows for expansion of the pillow block due to heat d. The very slow rotation of the needles in a needle bearing - ANSWER-a. The very slow rotation of the outer race 23. What principal do timing gears use? a. Stainless steel b. Endless belt c. Synthetic material d. Gear tooth - ANSWER-d. Gear tooth 24. A gear tooth with a larger pressure angle is said to be: a. Stronger b. Weaker c. Machined incorrectly d. Made for Helical gears - ANSWER-a. Stronger 25. What are gib joint bearings suited for? a. Heavy loads b. Light loads c. Limited side loading d. Strictly radial loads - ANSWER-c. Limited side loading 26. High-speed bearings and roller chain use what type of lubrication? a. Mist b. Bath c. Splash d. Dry - ANSWER-a. Mist 27. How much oil is required to lubricate a ball bearing? a. Enough to cover the entire bearing b. Enough to cover 1⁄2 of the bearing c. Enough to cover the outer race d. Enough to cover halfway up the bottom rolling element - ANSWER-d. Enough to cover halfway up the bottom rolling element 28. What is the breaker ply of a belt? a. Layer under the carcass to absorb shock b. Layer under the snub pulley c. The term given to the mechanical fastener holding the belt d. The term given to a larger head pulley - ANSWER-a. Layer under the carcass to absorb shock 29. What do you use to carry "fines" on a conveyor? a. Idler b. Camber slide c. Crown d. Snub - ANSWER-b. Camber slide 30. In a multi bearing system, how many bearings are fixed? a. All of them b. Only 1 of them c. None of them d. At least two - ANSWER-b. Only 1 of them 31. To change the direction of travel on a conveyor, you would use a: a. Snub pulley b. Tail pulley c. Bend pulley d. Head Pulley - ANSWER-c. Bend pulley 32. The approximate efficiency of a drive chain is: a. 100% b. 90% c. 98% d. 91% - ANSWER-c. 98% 33. What is the pitch of a #80 chain? a. 1" b. 1⁄2" c. 5/8" d. 3⁄4" - ANSWER-a. 1" 34. What is the overall length of a V- belt specified in? a. OD b. Circular pitch c. Pitch diameter d. Depends on the size - ANSWER-c. Pitch diameter 35. Where should the lubricant entry on a bearing be located? a. On the high pressure point b. On the low pressure point c. Anywhere d. Always at 90 degrees to the bottom - ANSWER-b. On the low pressure point 36. What is the housing of a friction bearing called? a. Base b. Cover c. Pillow Block d. Container - ANSWER-c. Pillow Block 37. A Conrad bearing is what type of bearing? a. Ball bearing b. Needle bearing c. Angular contact d. Thrust bearing - ANSWER-a. Ball bearing 38. A clearance fit means: a. Parts must be heated prior to assembly b. Parts fit together easily c. Parts must be welded d. Friction holds parts together - ANSWER-b. Parts fit together easily 39. Oil grooves in a Babbitt bearing are: a. Anywhere b. In the unloaded section c. On the top d. On the bottom - ANSWER-b. In the unloaded section 40. What is a shielded bearing? a. Rubber covers the rolling elements, sealing in the lubricant 53. The taper of a tapered bearing is: a. 1:96 b. 1:12 c. 1:100 d. 1:10 - ANSWER-b. 1:12 54. A tapered bearing has what letter at the end of its code? a. A b. C c. T d. K - ANSWER-d. K 55. A bearing in a gearbox, subject to splash lubrication is: a. Open b. Sealed c. Shielded d. Adjustable - ANSWER-a. Open 56. What is the bore of an SKF 6106 bearing? a. 6mm b. 30mm c. .06" d. 6" - ANSWER-b. 30mm 57. When an anti-friction bearing is fitted on a shaft in a fixed position, how is it held in place? a. Set screws b. Shaft collars c. Stabilizer rings d. Locknuts - ANSWER-c. Stabilizer rings 58. The best way to remove a bearing from a shaft is to use a set of pullers with the strain applied to: a. The outer race b. The inner race c. The shield d. The rolling elements - ANSWER-b. The inner race 59. Anti friction failure usually occurs due to: a. Over lubrication b. Overheating c. Vibration d. Contamination - ANSWER-d. Contamination 60. When mounting a pair of angular contact bearings, the best technique is: a. "O" arrangement (face to face) b. "X" arrangement (back to back) c. Tandem d. Spaced apart - ANSWER-a. "O" arrangement (face to face) 61. A short piece of material used to take up the space of the shaft when pouring Babbitt is called: a. Spacer b. Liner c. Mandrel d. Divider - ANSWER-c. Mandrel 62. You must remove water in a bearing assembly prior to pouring Babbitt because: a. It will cause blowback b. It will create steam pockets c. Babbitt will be weak d. Steam temperature will melt the Babbitt - ANSWER-a. It will cause blowback 63. What prevents a Babbitt bearing from rotating? a. Spacers b. Set screws c. Weld d. Dovetail grooves - ANSWER-d. Dovetail grooves 64. In a Babbitt bearing, the corners of the bottom half must be: a. Lubricated b. Sanded c. Relieved d. Filed smooth - ANSWER-c. Relieved 65. When precision shells are installed, they will extend past the face of the bearing housing. This is called: a. Clearance b. Allowance c. Gap d. Crush - ANSWER-d. Crush 66. A bearing is selected based on: a. Equipment requirements b. Ease of installation c. Type of maintenance to be performed d. Availability - ANSWER-a. Equipment requirements 67. Herringbone gears have: a. Straight teeth cut parallel to the shaft b. A formed point at the gear center c. A helix d. Minimal teeth in contact - ANSWER-b. A formed point at the gear centre 68. The distance a worm moves forward when making one complete revolution is called: a. Pitch b. Helix angle c. Lead d. Tooth form - ANSWER-c. Lead 69. The pitch circle of a gear may also be called: a. Diametral pitch b. Pitch diameter c. Outside diameter d. Circular pitch - ANSWER-b. Pitch diameter 70. The gear ratio of a single reduction worm gear is determined by the number of teeth on the gear and the: a. Worm pitch b. Helix angle c. Diameter of the gear d. The number of threads on the worm - ANSWER-d. The number of threads on the worm 71. The portion of tooth above the centerline is called: 82. When multiple belts are connected to form one belt, this is called: a. Group belts b. Endless belts c. Power bands d. Sectional belts - ANSWER-c. Power bands 83. The pitch line of a timing belt is located on the belt: a. Back b. Cover c. Tooth d. Neutral Line - ANSWER-d. Neutral Line 84. Belt tension is checked: a. On the slack side b. On the tight side c. Anywhere d. On the sheave - ANSWER-b. On the tight side 85. The term given to the amount of power a belt can transmit is related to: a. Creep b. Area of contact c. Speed d. Length - ANSWER-b. Area of contact 86. A belt drive has a pulley's of 10.125" and 6.625". Center distance is 12.375" What is the accurate belt length? a. 29.77" b. 51.90" c. 41.5" d. 51.29" - ANSWER-d. 51.29" L=2C+1.57(D1+d2)+[(D1-d2)²/4C] L=2(12.375")+1.57(10.125"+6.625")+[(10.125"-6.625")²/4(12.375")] L=24.75+26.2975+(12.25/49.5) L=51.2949 87. The best type of belt material is: a. Leather b. Rubber c. Polymers d. Plastics - ANSWER-c. Polymers 88. A notched V-belt is used for: a. High speed drives with short centres b. Low speed drives c. Large diameter pulleys with long centre distances d. Serpentine belt replacement - ANSWER-a. High speed drives with short centres 89. The function of a serpentine belt is to: a. Drive low speed b. Drive on both sides of the belt c. Increase area of contact d. Self tracking on the sheaves - ANSWER-b. Drive on both sides of the belt 90. Rim speed is the ft/min measured on the outside of the pulley. With a 6.25" pulley running at 2450 RPM what is the rim speed? a. 4000 ft/min b. 2000 ft/min c. 4900 ft/min d. 2450 ft/min - ANSWER-a. 4000 ft/min (6.25" x 3.14) = 19.625" 19.625"/12" = 1.635 1.635 x 2450 RPM = 4006.77 ft/min 91. The ratio of crowning of a roller relative to the face width is: a. 1:96 b. 1:100 c. 1:50 d. 1:12 - ANSWER-a. 1:96 92. How do you check for wear on the main bearings in a Diesel truck? a. Feeler gauge b. Taper gauge c. Plastic gauge d. Side play - ANSWER-c. Plastic gauge 93. If a single inlet fan has too much axial movement, what action is to be taken? a. Lock the bearing closest to the fan b. Lock all of the bearings c. Lock the bearing furthest from the fan d. Loosen all set screws - ANSWER-c. Lock the bearing furthest from the fan 94. A motor turns at 1000 RPM. This requires 1.5 Horsepower. What is the horsepower at 1500 RPM? a. 2.25 HP b. 3 HP c. 1.75 HP d. 1 HP - ANSWER-a. 2.25 HP 1.5 HP = 1000RPM x HP = 1500 RPM 1.5HP/1000RPM = 0.0015HP/RPM x 1500RPM = 2.25 HP 95. What type of engine has the highest compression ratio? a. Gasoline b. Diesel c. Propane d. Natural Gas - ANSWER-b. Diesel 96. A drive chain is riding at the top of the teeth on a sprocket. This is caused by: a. Too slack b. Too tight c. Worn out sprocket teeth d. Wrong pitch chain on the sprocket - ANSWER-c. Worn out sprocket teeth 97. How do you know if a bearing is tight enough on a sleeve? a. Pre-load condition b. Slight drag on the bearing c. Bottoms out d. Sleeve is loose - ANSWER-b. Slight drag on the bearing 98. What type of impellor is best for slurries? a. Closed impellor b. Open impellor c. Low speed pump d. High speed pump - ANSWER-a. Closed impellor b. 3.00" c. 2.59" d. 4.75" - ANSWER-3.125" - 1.250" = 1.875" difference 7.525"/12" = 0.627 ft 1.875" = 0.627ft x" = 1 ft 1.875"/0.627ft = 2.990" 112. A belt drive has pulleys of 9.6875" and 6.255". The center distance is 28.375". What is the accurate belt length? a. 81.5" b. 85.88" c. 81.88" d. 89.98" - ANSWER-c. 81.88" L=2C+1.57(D1+d2)+[(D1-d2)²/4C] L=2(28.375")+1.57(9.6875"+6.255")+[(9.6875"-6.255")²/4(28.375")] L=56.75"+25.0297+(11.7821/113.5) L=81.88" 113. An anti friction bearing is to be heated in an oil bath at 250 degrees. The inside diameter of the bearing is 3.5". What is the bore size after the heating? (Room temperature is 70 degrees) a. 3.50009" b. 3.501134" c. 3.65479" d. 3.49996" - ANSWER-b. 3.501134" 114. What prevents a bearing from seating on a shaft against the shoulder? a. Interference with threads b. Burrs on the shoulder c. Too much play in the rolling elements d. Poor manufactured bearing - ANSWER-b. Burrs on the shoulder 115. Which of the following best describes hypoid gears? a. Operate at non parallel, non intersecting axes b. Operate at parallel, intersecting axes c. Operate at non parallel, intersecting axes d. Operate at parallel, non intersecting axes - ANSWER-a. Operate at non parallel, non intersecting axes 116. What would cause a chain to ride on top of a sprocket? a. Worn shaft b. Chain pitch to small c. Chain stretched d. Chain not lubed - ANSWER-c. Chain stretched 117. How does a labyrinth seal work? a. non contact seal that permits liquid to be forced through centrifugal force to the outside of its grooves b. A series of packing rings with the joints installed at opposite sides c. A contacting seal that heats up and melts around the shaft d. A non contact seal that contains an absorbent that swells when contacted with the pumping fluid - ANSWER-a. non contact seal that permits liquid to be forced through centrifugal force to the outside of its grooves 118. Tapered roller bearings are best described as: a. Permit axial and radial loads b. Permit axial load only c. Permit radial load only d. Permit side load - ANSWER-a. Permit axial and radial loads 119. How is a belt adjusted that is running out to one side? a. square up head and tail pulleys b. Add another snub pulley c. Heat up belt to stretch d. Remove breaker ply - ANSWER-a. square up head and tail pulleys 120. How are hydraulic jacks stored? a. fully extended in the vertical position b. Fully retracted in the vertical position c. Fully extended in the horizontal position d. Fully retracted in the horizontal position - ANSWER-b. Fully retracted in the vertical position 121. What is the primary purpose of a woodruff key? a. Avoids having to machine too much metal away from stressed areas of shaft b. Transmits huge force between mating parts c. Used as a self aligning type of key in place of square keys d. Used in any application a square key would be - ANSWER-a. Avoids having to machine too much metal away from stressed areas of shaft 122. How many teeth on a driven spur gear will create a 2:1 ratio when the drive gear has 90 teeth, and the idler has 10 teeth? a. 50 tooth b. 45 tooth c. 40 tooth d. 10 tooth - ANSWER-b. 45 tooth 123. What type of maintenance is an oil change? a. predictive b. proactive c. reactive d. preventive - ANSWER-d. preventive 124. What percent of a chain is left slack on a chain drive set up? a. 1% b. 2% c. 3% d. 4% - ANSWER-d. 4% 125. What causes a heat exchanger to leak internally? a. bolts loose b. fluid too cold c. fluid warm d. Gasket ripped - ANSWER-d. Gasket ripped 126. Bearing wear on start up is caused by: a. Lack of oil wedge b. High speed c. Low speed d. Hot environment - ANSWER-a. Lack of oil wedge