ADVANCED MANUFACTURING AND MECHATRONICS (MANU2488) SAMPLE TEST QUESTIONS QUESTION 1 _______ _________ Select the correct answer from the following questions. Select only one answer unless otherwise requested. 1.1 Machined parts can be classified as rotational or non-rotational. Which one of the operations can create non-rotational geometries? A. Drilling. B. Milling. C. Tapping. D. Turning 1.2 A lathe can be set up to perform which two of the following machining operations? A. Boring. B. Milling. C. Drilling. D. Ultrasonic machining. 1.3 G03 can be cancelled by: A. G00 B. G01 C. G02 D. any of the above 1.4 Which one of the following is NOT among the four principal energy forms used to remove material in the non-traditional machining processes? A. Atomic. B. Chemical. C. Electrical. D. Mechanical. 1.5 Abrasive water jet machining can be used to machine both metallic and non-metallic materials. A. True B. False 1.6 Which one of the following is NOT a benefit attributed to additive manufacturing? A. Better ability to visualise the part. B. Higher customisation. C: Increased ability to make complex parts. D. Fast production rate in high volumes. 1.7 In casting processes, a runner is which one of the following? A. The rollers on which a mold is moved B. Worker who moves the molten metal to the mold C. Channel in the mold leading from the downsprue to the main mold cavity D. Vertical channel into which molten metal is poured into the mold 1.8 Accuracy is best described as: A. The smallest difference in a dimension that a measuring instrument can detect B. Degree of repeatability in the measurement process C. Degree to which a measured value agrees with the true value of interest D. Variation in manufacturing 1.9 Screws and bolts can be specified in either metric standards or U.S. standards. The metric standard specification consists of the nominal major diameter followed by which one of the following? A. Head style B. Length C. Number of threads per inch D. Pitch QUESTION 2 _______ _________ 2.1 What is the typical relationship between product variety and production quantity in manufacturing? Explain briefly. 2.2 Name 4 operations that can be performed in a lathe and state how the tool is fed in these operations. 2.3 Identify the three basic components of a numerical control system and briefly describe their functions. QUESTION 3 _______ _________ A cylindrical workpart 200 mm in diameter and 700 mm long is to be turned on an engine lathe. Cutting conditions are as follows: cutting speed is 2.30 m/s, feed is 0.32 mm/rev, and depth of cut is 1.80 mm. Determine (a) final diameter of the workpiece (b) cutting time, and (c) material removal rate. L=700mm = 200mm QUESTION 4 _______ _________ 4.1. A Titanium part built by Selective Laser Melting (SLM) has a height of 85mm. Estimate the total build time for the part in hours and minutes (excluding set-up and clean-up processes) if: Each layer is 50 µm thick The laser scanning time per layer is an average of 43 seconds The powder recoating time for each layer is 30 seconds QUESTION 5 _________________ One of your colleagues has asked you to check their CNC code. The part which needs to be produced is shown below, with set point coordinates and other features. Points X (mm) Y (mm) P0 0.0 0.0 P1 20.0 20.0 P2 35.0 20.0 P3 35.0 45.0 P4 55.0 45.0 P5 127.5 50.0 P6 148.0 50.0 P7 168.0 80.0 P8 168.0 105.0 P9 133.0 105.0 P10 67.5 125.0 P11 30.0 125.0 P12 15.0 110.0 P13 15.0 70.0 P14 5.0 45.0 P15 20.0 35.0 P16 91.25 60.0 P17 100 140.0 The code your colleague gives you is below. Your colleague has put the code into sections because they know there is something wrong with the code. Look at each block and fix the code. There are some clues below. The machine details are: ------------------------------------------------------------------------------------------------------------------------------- % O101 N010 G21 G40 G49 G17 N020 G91 G28 Z0 N040 G90 N060 G00 G54 X0 Y0 S2600 M03 N070 G43 H03 Z12.0 N080 G42 X20.0 Y20.0 D03 N090 G01 Z-5.0 F500. N100 X35.0 Y20.0 ------------------------------------------------------------------------------------------------------------------------------- N110 Y45.0 N120 X55.0 N130 G03 X127.5 Y50.0 I-36.25 J-15.0 N140 G01 X148.0 N150 X168.0 Y80.0 N160 Y105.0 N170 X131.0 N180 G02 X67.5 Y125.0 I32.5 J35.0 N190 G01 X30.0 ------------------------------------------------------------------------------------------------------------------------------- N200 X15.0 Y110.0 N210 Y70.0 N220 X5.0 Y47.0 N230 G03 X20.0 Y20.0 I15.0 J+10.0 N240 Z10.0 N250 G00 G40 X0. Y0. N260 M05 N280 G91 G28 Z0 N290 G28 X0 Y0 N300 G90 N310 M30 % a) For the first section there are two lines of code missing. Write down what you think these extra lines should be, with appropriate line numbers to indicate where they should go. b) In Section Two there are 5 errors within the lines of code. Write down the correct programming below c) In Section Three there are 2 errors within the lines and one line is missing. Write down the correct programming below for the two incorrect lines d) Write down the additional line, with appropriate line number below QUESTION 6 ______________ A hot forging operation is performed in an open die on a cylinder. Initial diameter of the cylindrical work part is 30 mm, and its height is 50 mm. The part is pressed to an average diameter of 45 mm. The work metal at this elevated temperature yields at 90 MPa. Coefficient of friction at the die-work interface is 0.40. Given a hot forging operation, assume the strength coefficient is equal to the yield strength and the strain hardening exponent is zero. Determine the: a) The final height of the part b) Maximum force in the operation QUESTION 7 ______________ Recommend a general manufacturing process for each of the following applications and briefly explain your choice: a) The manufacture of an aluminium alloy fuel nozzle. Approximate length 20cm, diameter 10cm. Annual production quantities will be approximately 1000 units. b) A gas turbine blade made from a high temperature resistant nickel alloy. Length approximately 10cm. Annual production quantity 1000 units c) The manufacture of a thermoplastic sink. Annual production quantities will be approximately 20,000 units per year. d) The manufacture of an aluminium housing for a pump. Annual production quantities will be approximately 100,000 units per year.
欢迎咨询51作业君
