CNC Knowledge: CNC Lathe Theory Test Questions

1. Single choice (Questions 1 to 80. Choose a correct answer and fill in the corresponding letters in parentheses in the question. Each question is worth 1 point, for a total score of 80 points.)
1. The basic norms of professional ethics do not include ().
A. Obey laws and regulations, be honest and truthful
B. Compete fairly and act in accordance with the law
C. Love your work, be dedicated and faithful to your duties
D. Serving the masses and contributing to society
2. Dedication to work and dedication to work are the main requirements of employees ( ).
A. Attitude at work
B. Spirit of work
C. Work capacity
D. All of the above is acceptable
3. A high sense of responsibility must be achieved ( ).
A. Strong sense of responsibility, working tirelessly and not afraid of trouble
B. Not selfish or seeking personal gain
C. Emphasis on credibility and image
D. High edge and high edge, consistent inside and out
4. Keeping the work environment clean and tidy is incorrect ().
A. A clean working environment can boost employees’ minds
B. Optimize the work environment
C. Remove oil stains after work is completed
D. Blanks and semi-finished products are carefully stacked according to regulations.
5. The intersection line produced after the cylinder is intersected by a plane perpendicular to the axis is ( ).
Around
B.Rectangle
C. Ellipsis
D. straight line
6. Regarding the “partial view”, which of the following statements is false ( ).
A. The view of the symmetrical part of the machine can only be drawn in half or quarter, and two thin parallel continuous lines perpendicular to the central axis of symmetry can be drawn at both ends.
B. Fracture boundaries in partial views are shown as wavy lines. When the local structure they represent is complete and the outer contour is closed, the wavy lines can be omitted.
C. When drawing a partial view, usually mark the view name “A” above the partial view, use an arrow near the corresponding view to indicate the projection direction, and add the same letter.

7. Which of the following statements is correct ( )
A. The full section view is used for parts with complex internal structures.
B. When the shape of the machine part is close to the opposite direction, the half-section view cannot be used in any way.
C. When using a partial section view, the wavy line can be drawn on the extension line of the contour line.
D. The half-section view is used for symmetrical parts with complex internal and external shapes.
8. Commonly used inoculants for gray cast iron inoculation treatment are ().
A. Ferromanganese B. Magnesium alloy C. Chromium D. Ferrosilicon
9. Polyamide (nylon) belongs to ().
A. Thermoplastic B. Cold plastic C. Thermosetting plastic D. Thermoflexible plastic
10. Those that do not belong to friction belt drive include ( ).
A. Flat belt drive B. V-belt drive C. Synchronous belt drive D. Poly-ribbed belt drive
11. ( ) is composed of a driving gear, a driven gear and a frame.
A. Gear drive B. Worm gear drive C. Belt drive D. Chain drive
12. Micrometer reading time ( ).
A. Cannot be deleted B. Must be deleted
C. It is best not to remove it. D. Remove it first, then lock it, then perform reading.
13. The measuring range of the universal angle ruler is ( ).
A、0°～120° B、0°～180°C、0°～320° D、0°～270°
14. The first step of the reduction housing processing process is completed ( ), connection holes and positioning holes.
A. Side B. End face C. Bearing hole D. Main plane
15. The heat treatment method after shaving the lathe spindle box gears is ().
A. Normalizing B. Tempering C. High frequency quenching D. Surface heat treatment
16. The error when measuring the workpiece with a steel ruler ( ).
A. Maximum B. Largest C. Smallest D. Smallest
17. The file cannot be ( ) when used.
A. Used as a crowbar B. Used as a crowbar and hand hammer
C. For hand hammer D. Side
18. If a small number of non-standard holes must be reamed for single-part production and repair work, reamers ( ) should be used.
A. Built-in cylinder B. Adjustable type C. Conical type D. Spiral groove
19. It is not necessary to check ( ) before using the engine.
A. Is the wiring correct? B. Is the grounding reliable?
C. The power factor level D. Is the insulation good?
20. Practices likely to cause mechanical injuries are ( ).
A. Do not operate rotating parts until they have stopped. B. Do not cross the rotating machine shaft.
C. No objects should be placed on rotating parts. D. Fewer tools should be placed on rotating parts.
21. When processing the box, the ( ) of the box should be processed first, and then each hole and other height direction planes should be processed according to this area.
A. Bottom plane B. Side plane C. Top surface D. Reference hole
22. The oblique axonometric drawing method is that the axonometric projection plane is parallel to a coordinate plane, and when the projection direction ( ) is on the axonometric projection plane, the oblique axonometric drawing can be obtained.
A. Parallel B. Perpendicular C. Inclined D. Overlap
23. The ( ) of the spindle housing is used to control the starting, stopping, reversing and braking of the spindle.
A. Control mechanism B. Reversing mechanism C. Shifting mechanism D. Braking mechanism

24. Most fixed gears, sliding gears, and the drive shafts that support them in the feed box are connected by ( ), and some gears are connected by flat keys or semicircular keys.
A. Splined connection B. Interference connection C. Spanner connection D. Jack-screw connection
25. The steps to read the assembly drawing are ( ) first.
A. Read the title bar B. Look at the view configuration C. Look at the dimension D. Look at the technical requirements
26. In precision screw processing technology, the requirement ( ) is to make the material grains refined, structure tight and carbides distributed evenly, which can improve the strength of the material.
A. Complete cooling B. Straight effect C. Forging blank D. Spheroidizing annealing
27. Parts whose processed surface is parallel to the reference plane can be clamped and processed on ( ).
A. Three-claw chuck B. Four-claw chuck C. Faceplate D. Faceplate angle
28. Specifications for mechanical transformation processes specify the manufacturing process and the operating methods of the products or parts ( ).
A. Process documents B. Process specifications C. Process educational materials D. Process methods
29. Determining the processing sequence and process content, processing methods, dividing processing steps, and organizing heat treatment, inspection and other auxiliary processes are the main tasks of ( ).
A. Develop a process route B. Develop processing technology C. Complete process documents D. Review and approve process documents
30. Under certain production conditions, with the minimum ( ) and lowest cost, in accordance with the provisions of the production plan, the production of qualified products is the principle that should be followed in the formulation of process regulations.
A. Electricity consumption B. Labor consumption C. Material consumption D. Material consumption
31. Due to the high spindle speed of CNC lathes, ( ) high-speed electric chucks are often used.
A. Pneumatic B. Hydraulic C. Mechanical D. Screw
32. The allowable push-pull force of K93 high-speed hydraulic chuck with 200mm specification is ( )N.
A, 4500 B, 600 C, 450 D, 480
33. The following points ( ) are not points that should be paid attention to when using CNC centers.
A. The holding force of the upper holding parts cannot be too large or too small.
B. Do not hit, disassemble or tighten the cable gland at will to avoid damage to the precision.
C. After use, it should be cleaned, rust-proofed and stored properly. D. It can be used as a reference for centering when installing the tool.
34. In order to ensure that the center of the CNC self-centering rest clamping parts coincides with the center of the machine tool spindle, ( ) should be used for adjustment.
A. Lever indicator and dial indicator B. Test rod and dial indicator
C. Micrometer and test rod D. Micrometer and lever indicator
35. The cylindrical turning tool of the CNC lathe is installed on the turret cutting head of the turret tool holder via ( ).
A. Tool holder bush B. Locating ring C. Tool holder seat D. Locating bush
36. In the plane Cartesian coordinate system, the central coordinate of the circle is (30, 25), the radius is 25, and the equation of this circle is ().
A、(X—30)2+（Y—25）2=252
B、(X+30)2+（Y+25）2=252
C、(X—30)+（Y—25）=25
D、(X+30)+(Y+25)=25
37. The workpiece ( ) can be processed on CNC machine tools.
A. Rough machining B. Difficult to process with ordinary machine tools
C. Unstable white balance D. Large batch
38. For CNC machined parts, dimensions must be marked ( ) on the part drawing. This type of dimensional marking is convenient for programming.
A. Design basis B. Assembly basis C. Same basis D. Measurement basis
39. CNC machining places higher demands on cutting tools than ordinary machining, especially in terms of tool rigidity and ( ).
A. Manufacturing B. Resistance C. Robustness D. Durability

40. ( ) is not suitable for entering complex machining programs into CNC devices.
A. Strip of paper B. Disc C. Computer D. Keyboard
41. A complete program consists of three parts ( ), the content of the program and the end of the program.
A. Part name B. Program number C. Part number D. Address code
42. In the ISO standard, G00 is the command ( ).
A. Relative coordinates B. Outer circle cycle C. Quick point positioning D. Coordinate system setting
43. The following ( ) does not constitute a criterion for measuring the quality of programs.
A. Short programming time B. Good treatment effect C. Strong versatility D. Extensive operating instructions
44. If a group of program segments appears several times in a program, it can be made into a fixed program and named separately. The program is called ().
A. Treatment program B. Subprogram C. Small program D. Subprogram
45. In the FANUC system, the G90 instruction is used in programming ().
A. Deep hole drilling B. End face with large allowance C. Outer circle with large allowance D. Large pitch thread
46. ​​Program segment G90 X52 Z—100 F0.3
X48
The meaning is ( ).
A. Rotate a 100 mm long cone B. Rotate a 100 mm long cone with a head diameter of 52 mm
C. Use two tools to make a round bill with a diameter of 48 mm and a length of 100 mm.
D. Rotate a cone 100 mm long and 48 mm in diameter at the small end
47. In the FANUC system, the G92 command can process ( ).
A. Cylindrical thread B. Internal thread C. Taper thread D. All of the above are acceptable
48. In program segment G94 X30 Z—5 R3 F0.3, the meaning of R3 is ().
A. The end point of the outer circle B. The axial dimension of the inclined plane C. The end point of the inner hole D. The end point of the thread
49. In the FANUC system, the command ( ) is an outer diameter roughing cycle command.
A, G70 B, G71 C, G72 D, G73
50. In the G72P (ns) Q (nf) U (△u) W (△w) S500 program format, ( ) represents the sequence number of the first block of the arrival path.
A、△w B、ns C、△u D、nf
51. The control ( ) is a fixed shape rough machining cycle control, mainly used for rough machining of forging and foundry blanks.
A, G70 B, G71 C, G72 D, G73
52. In the G73P (ns) Q (nf) U (△u) W (△w) S500 program format, ( ) represents the sequence number of the last block of the arrival path.
A、△w B、nf C、△u D、ns
53. G75 control is mainly used for ( ) machining to facilitate chip breaking and removal.
A. Grooving B. Drilling C. Bar D. Interrupted end face

54. In the program format of G75
A、KB、Δd C、Z、D、R

55. In the FANUC system, ( ) means that the program is paused. After pressing the start button again, the following program segments will continue to be executed.
A, M00 B, M01 C, M02 D, M30
56. In the FANUC system, the M20 command is the command ( ).
A. Chuck is loose B. Cutting fluid is off C. Cutting fluid is on D. Air is on
57. In the FANUC system, the M11 command is the command ( ).
A. Chuck is tight B. Coolant stops C. Coolant is in place D. Chuck is loose
58. In the FANUC system, the M22 command is the command ( ).
A. X-axis mirroring B. Unmirroring C. Y-axis mirroring D. Open air
59. In the FANUC system, the M98 command is the command ( ).
A. Low spindle speed range B. Call subroutine C. High spindle speed range D. End of subroutine
60. Once the NC fault has been cleared, press the RESET key ( ).
A. Clear alarm B. Reschedule C. Edit program D. Return to reference point
61. The clamping force of the CNC lathe chuck is adjusted by ( ).
A. Variable pump B. Relief valve C. Directional valve D. Pressure reducer
62. Most of the hydraulic pumps in the hydraulic system of CNC lathe can be used as ().
A. Hydraulic motor B. Relief valve C. Directional valve D. Pressure regulating valve
63. The G72 command is a loop command ( ).
A. Finishing B. Roughing the outer diameter
C. End face blank D. Fixed shape blank
64. G75 X20.0 P5.0 F0.15 block is an intermittent end face cutting cycle control, used for processing ( ).
A. Drilling B. External groove C. End face D. Outside diameter
65. When the CNC machine tool advances manually, the mode selection switch should be set to ( ).
A、JOG FEED B、RELEASE C、MDI D、HANDLE FEED
66. When the CNC machine tool is in automatic state, the work ( ) can be completed.
A. Part processing B. Cycle C. Zero return D. Manual feed
67. The mode selection switch should be set to ( ) when the CNC machine tool is in the editing state.
A、JOG FEED B、PRGRM C、ZERO RETURN D、EDIT
68. When the CNC machine tool wants ( ) to overtravel, the mode selection switch should be set to 0.T RELEASE.
A. Automatic state B. Manual data entry C. Return to zero D. Release

69. When the position of the manual pulse generator selection switch of the CNC machine tool is at X10, the handwheel power unit is ().
A. 0.01 mm/grid B. 0.001 mm/grid C. 0.1 mm/grid D. 1 mm/grid
70. When the coolant switch of the CNC machine tool is in the ( ) position, it is a switch for manual control of the coolant.
A, PIN B, OFF C, COOLANT ON D, M CODE
71. When the switch of the tailstock sleeve of the CNC machine tool is in position ( ), the sleeve moves forward.
A、M CODE B、BACK C、COOLANT ON、FORWARD
72. When the program protection switch of the CNC machine tool is in the ON position, the program cannot be executed ( ).
A. Enter B. Edit C. Delete D. All of the above are correct
73. When the single-block execution switch of the CNC machine tool is turned to SINGLE BLOCK, the program ( ) is executed.
A. Single segment B. Continuous C. Choice D. Unable to judge
74. For dimensional accuracy of deep hole parts, ( ) can be used to check.
A. Bore micrometer or bore dial indicator B. Plug gauge or bore micrometer
C. Plug gauge or inner caliper D. All of the above are acceptable
75. Parts with large eccentricity cannot be measured by direct measurement ( ). In this case, dial indicators and micrometers can be used to measure indirectly.
A. Dimensional accuracy B. Shape accuracy C. Eccentricity D. All of the above are acceptable
76. When turning shaft parts, if the gross margin is uneven and the amount of backcut changes during the cutting process, the workpiece will produce errors ( ).
A. Cylindricity B. Dimensions C. Coaxiality D. Roundness
77. When turning holes, if the hole turning tool is worn, the tool holder will vibrate and the hole will be unscrewed ( ).
A. Cylindricity is out of tolerance B. Surface roughness is high C. Roundness is out of tolerance D. Dimensional accuracy is out of tolerance
78. The reason for the error ( ) when using the profiling method to rotate a cone is that the angle of the jig is incorrectly adjusted.
A. Size B. Shape C. Position D. Cone (angle)
79. When turning the thread, improper use of the dial will cause errors in the thread ( ).
A. Large diameter B. Medium diameter C. Tooth angle D. Roughness
80. When turning holes in box-type parts, if the turning tool is worn, the hole will produce an error ( ).
A. Axis straightness B. Cylindricity C. Roundness D. Coaxiality
2. Judgment questions (Questions 81 to 100. Fill in the judgment results in parentheses. Fill in “√” if correct and “×” if incorrect. Each question is worth 1 point and the total score is 20 points.)
81. ( ) Keeping the workplace clean will help improve work efficiency.

82. ( ) The basic requirements for tool materials are manufacturing quality and wear resistance.
83. ( ) Commonly used tool materials include carbon tool steel, alloy tool steel, high speed steel and hard alloy steel.
84. ( )The amount of movement of the micrometer screw is generally 25 mm.
85. ( ) Cutting fluids are divided into two categories: cutting fluids in aqueous solution and cutting fluids in oil solution.
86. ( )Three-line worm part drawings are often expressed as a front view, a section view (section removed), and a top view.
87. ( ) The longer transmission shaft of the main spindle housing adopts a three-support structure to improve the precision of the transmission shaft.
88. ( ) The function of the feed box is to transfer the movement of the interchange gearbox to the lead screw or light rod by changing the position of the sliding gear in the box to meet the needs of the circle exterior of the car and motorized power supply.
89. ( ) The turret tool holder of the CNC lathe has a simple mechanical structure and a relatively high failure rate during use, so sufficient attention should be paid to the use and maintenance.
90. ( ) Due to inertia and deformation of the process system, rotating threads will cause excessive or insufficient stroke.
91. ( ) The electrical cabinet filter which must be inspected and maintained weekly for CNC lathes.
92. ( ) The V-belt driving the spindle of the CNC lathe should be inspected and maintained every six months.
93. ( ) Block G71 P0035 Q0060 U4.0 W2.0 S500 is the control of the outer diameter roughing cycle.
94. ( ) G73 P0035 Q0060 U1.0 W0.5 F0.3 block is a fixed shape roughing cycle control.
95. ( ) In program section G74 Z—80.0 Q20.0 F0.15, Z—80.0 means drilling depth.
96. () When the CNC machine tool is in rapid feed, there are four options for the feed.
97. ( ) When using a gauge block to check the angle error of the shaft diameter, the formula for calculating the height of the gauge block is as follows:
h=M—0.5（D+d）—Rsinθ.
98. ( ) When testing the verticality of the three-dimensional offset holes on the boxed part, install a cent indicator on the reference chuck, place the measuring head on the cylindrical surface of the measuring chuck, rotate it 90 ° then measure again. , you can determine the axis of the two holes. Squareness error in measured length.
99. () Integrate the two halves of the box into one through the positioning piece or positioning element, and insert the inspection mandrel into the hole to be measured. If the inspection chuck can pass freely, it means that the parallelism meets the requirements.
100. ( ) Use three needles to measure the normal thickness of the worm’s teeth. The formula for calculating the diameter of the measuring needle is dD=0.577P.

Answer
Answers to the advanced theoretical knowledge test for lathe (CNC specific gravity)
1. Single choice (Questions 1 to 80. Choose a correct answer and fill in the corresponding letters in parentheses in the question. Each question is worth 1 point, for a total score of 80 points.)
1. B 2. A 3. A 4. C 5. A 6. D 7. D 8. D

9. A 10. C 11. A 12. C 13. C 14. D 15. C 16. B

17. B 18. B 19. C 20. D 21. A 22. C 23. A 24. A

25. A 26. C 27. D 28. A 29. A 30. B 31. B 32. A

33. D 34. B 35. C 36. A 37. B 38. C 39. D 40. D

41. B 42. C 43. D 44. B 45. C 46. C 47. C 48. B

49. B 50. B 51. D 52. B 53. D 54. B 55. A 56. D

57. D 58. C 59. B 60. A 61. D 62. A 63. C 64. B

65. D 66. A 67. D 68. D 69. A 70. C 71. D 72. D

73. A 74. A 75. C 76. D 77. B 78. D 79. B 80. B

2. Judgment questions (Questions 81 to 100. Fill in the judgment results in parentheses. Fill in “√” if correct and “×” if incorrect. Each question is worth 1 point and the total score is 20 points.)

81. √ 82. × 83. √ 84. √ 85. √ 86. × 87. × 88. ×

89. × 90. × 91. √ 92. √ 93. √ 94. √ 95. √ 96. ×

97. √ 98. × 99. × 100. ×