M A N U F A C T U R I N G P R O C E S S E S ME A S S I G N M E N T

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1 H.- J. Steinmetz, Jan. 005 M A N U F A C T U R I N G P R O C E S S E S ME 38.3 A S S I G N M E N T A manufacturing plant shop has 60 workers and one shop foreman. The shop has to manufacture a quantity of 1000 rollers, shown in the attached drawing, in the most economical and efficient way on a 1HP CNC-lathe. The shop foreman's wage is $.00/hour. The overhead cost for administration and engineering for this small machine shop is 65%. The cost for the 55.0mm diameter 4CrMo4 bar stock material, with a specific cutting force of 400 N/mm, is $ 5.0 per foot including all taxes. Since the spindle bore of the lathe is only 35mm the bar stock does not feed through the spindle. Therefore each workpiece has to be cut on a circular saw and machined from both sides on the CNC lathe. The hourly rate for a circular saw is $4/hour and the saw blade width =.5mm. The flank wear factor for all tools is 0.3 mm. Leave an equal amount (ap= 0.5 mm) of material for the finishing tools. The energy cost for the lathe = $0.18/kW. The delay time, tv, is 10% of tg for all time calculations. CNC - Lathe : n max. = 300 RPM, E = The replacement cost for this machine = $7, Cost for space Cs=$1,00.00/year. The maintenance cost Cm=$,000.00/year. Tool and insurance cost Co = $4,800.00/year. The Lathe is used in eight-hour shifts a day, 5 days a week for 5 weeks each year, for a utilization time of 6 years with an 8% interest rate. The $18.40/hour wages paid to the CNC machining technician includes all benefits. CNC tools 1st Set-up Xset Zset Vc n Rs D.O.C. max f Tool Tool# ID# (mm) (mm) (m/min) (rpm) (mm) (mm) (mm/rev) External roughing Drilling Internal roughing Internal finisching Internal threading External finishing CNC tools nd set-up Xset Zset Vc n Rs D.O.C. max f Tool Tool# ID# (mm) (mm) (m/min) (rpm) (mm) (mm) (mm/rev) External roughing Drilling Internal roughing Internal finisching External finishing

2 THE LAB REPORT HAS TO INCLUDE THE FOLLOWING IN SEQUENCE: H.- J. Steinmetz, Jan Calculate the workpiece datum and the reference points for the CNC-machine for both setup s. The safety distance for the tool change position u=5.0 mm.. Calculate the N.O.C. (number of cuts) for T01, leaving the required amount of material for the finishing tool and calculate the maximum power used for this external roughing tool. 3. Calculate all start and endpoints for each pass for T01 with tool nose radius compensation for both set-up s. Show the geometry for all points. 4. Calculate the power needed for the drilling operations, the feed force, the torque and the chip removal rate for the drill, T0. 5. Calculate for both set-up s the N.O.C. (number of cuts) for T03, leaving the required amount of material for the finishing tool and calculate the maximum power used for this internal roughing tool. 6. Calculate for both set-up s all start and endpoints for each pass for T03 with tool nose radius compensation. Show the geometry for all points. 7. Calculate for both set-up s the tool nose radius compensation calculation for the internal finishing tool T04. Show the geometry for all points. 8. Calculate the N.O.C. (number of cuts) and the programming values in X-direction for the threading tool, using the following depth: 0.35mm, 1 0.5mm, mm, 1 0.1mm and mm. Repead the last cut twice at the diameter 4mm. 9. Calculate for both set-up s all start and endpoints for the finishing tool with tool nose radius compensation. Show the geometry for all points (T06). 10. Calculate the feed rates for the finishing tools, based on the required surface finish. 11. Write a Program for the CNC-Lathe for each set-up. Use CNC-SPACE to format the text. Use CNC-Plot to check your program for errors. If nessesary debug and optimize both programs. 1. Calculate the expected tool life for T01. The following paramers for the insert KC850 are known from an exponent table: C=140, F=-0.1, E=-0.34, G= Calculate the machining rate C and the hourly rate for the CNC lathe. 14. Find the process time for the circular band saw. 15. Find the process time for the CNC-Lathe. 16. Fill in a Job card for this process with all set-up times and machining times. 17. Tabulate the total cost of this manufacturing process.

3 Rz 8 Rz 8 Rz 8 Rz 8 3

4 4

5 O005-A & O005-B O005 Roller 4CrMo4V, Barstock diam. 55mm, L=104mm January 005 ZW=.3 Part A First Set-up X 1st Set-up: Hard Jaws nd Set-up: Soft Jaws ZW=0 Part B Second Set-up 5

6 1. REFERENCE POINT CALCULATION for CNC - PROGRAM No. O005 A DATE 16-Jan-05 What is the ZW to use for these calculation? ZW =.300 Mm How long is the workpiece? LW = Mm What is the safety distance? u = Mm X home 5.77 mm TOOL DIMENSIONS Z home mm X-set Z-zet L max REFERENCE TOOL T T T T T T CALCULATION of WORKPIECE DATUM (W) X = mm Z = mm CALCULATION of REFERENCE POINT (RP) for TOOL CHANGE REFERENCE TOOL RP X = mm RP Z = mm CALCULATION of REFERENCE POINT (RP) for TOOL CHANGE T01 RP X = mm RP Z = mm T0 RP X = mm RP Z = mm T03 RP X = mm RP Z = mm T04 RP X = mm RP Z = mm T05 RP X = mm RP Z = mm T06 RP X = mm RP Z = mm 6

7 1. REFERENCE POINT CALCULATION for CNC - PROGRAM No. O005 B DATE 3-Jan-05 What is the ZW to use for these calculation? ZW = mm How long is the workpiece? LW = mm What is the safety distance? u = mm X home 5.77 mm TOOL DIMENSIONS Z home mm X-set Z-zet L max REFERENCE TOOL T T T T T05 15 T CALCULATION of WORKPIECE DATUM (W) X = mm Z = 5.89 mm CALCULATION of REFERENCE POINT (RP) for TOOL CHANGE REFERENCE TOOL RP X = mm RP Z = mm CALCULATION of REFERENCE POINT (RP) for TOOL CHANGE T01 RP X = mm RP Z = mm T0 RP X = mm RP Z = mm T03 RP X = mm RP Z = mm T04 RP X = mm RP Z = mm T05 RP X = mm RP Z = mm T06 RP X = mm RP Z = mm 7

8 Depth of cut and power requirement for the CNC lathe, T01 1st Set-up D= 55 mm N.O.C.= (D-d)/D.O.C./ d= 51 mm N.O.C.= 1 D.O.C.= mm T01 Power requirement for turning ap = D.O.C.=.0 mm ap f kc Vc VB E Input Answers Power kw Power HP Equation nd Set-up D= 55 mm N.O.C.= (D-d)/D.O.C./ d= 41 mm N.O.C.= 5.0 D.O.C.= 1.4 mm T01 Power requirement for turning ap = D.O.C.= 1.4 mm ap f kc Vc VB E Input Answers Power kw Power HP Equation ap * f * kc * Vc P= VB 60 *10 * E 3 in KW 8

9 3. Start and Endpoint calculations for T01 1 st Set-up P1: X59.0 Z100.5 P5: X55.0 Z8.0 P6: X51.0 Z10.5 P4: X51.0 Z8.0 P8: X51.0 Z99.04 P4: X51.0 Z10.5 P7: X Z10.5.0mm.5mm P3: X1.0 Z10.5 W P: X-3.0 Z100.5 X = D+ b Z = L a Z X1= D a X Z1 = L+ b α = 45 Point 1 D L Rs a Angle b Safety tan 0 to input X X = Z result result X X result Z Z

10 3. Start and Endpoint calculations for T01 nd Set-up P5 X55.0 Z70.5 P1 X59.0 Z100.5 P4 & P10 X5. Z70.5 P9 X50.0 Z69.00 P6 X55.0 Z10.5 Barstock diam. X55 mm P3 & P11 X5. Z10.5 P8 & P15 X49.4 Z70.5 P7 & P16 X49.4 Z10.5 P14 X Z70.5 P1 & P0 X46.6 Z10.5 P13 & P19 X46.6 Z70.5 P17 & P4 X43.8 Z10.5 P18 & P3 X43.8 Z70.5 P1 X41.0 Z10.5 P X41.0 Z70.5 P7 X41.0 Z96.8 R3.7 P5 X33.6 Z10.5 P6 X33.6 Z100.5 P3 X1.0 Z10.5 P X-3.0 Z100.5 Tool nose radius compensation calculation for T01, 45 degr. Chamfer GEO Figure 5 X = D + b Z = L a Z X1 = D a X Z1 = L + b α = 45 α X = Rs C = Rs B *tan α X = Rs ( Rs + b) tan Point 1 D L Rs a Angle b Safety tan 0 to input X X = Z result result X X or result Z Z or

11 4. Power requirement for drilling, feed force, torque & chip removal rate T0 D * f * kc * Vc in KW 4 1 *10 * E Solid drilling P= VB Feed force F drilling = D * f * kc in N Torque M drilling = D * f * kc 8*100 in Nm Chip removal rate V drilling = D * π * Vc 4000 in 3 cm / min 4 Power requirement for drilling, T0 T0 Power requirement for drilling Answers D f kc Vc n Pi VB E Input Power Power Equation kw HP (1) () Feed force for drilling D f kc Edges N lbf Torque for drilling D f kc Nm lbf-ft Chip removal rate for drilling 3 3 cm / min in / min D Vc Pi

12 5. Calculate D.O.C. and Power requirement for T03, 1 st Set-up P17 P14&P18 P10&P15 P6&P11 P13&P19 P9&P16 P5&P1 P1&P8 P4 P&P7 P3 Depth mm Drill diam. 0 Depth of cut, T03 1st Set-up D= mm N.O.C.= (D-d)/D.O.C./ d= 0 mm N.O.C.= D.O.C.= mm ap * f * kc * Vc P= VB 3 60 *10 * E T03 Power requirement for turning D.O.C. ap = = 0.9 mm ap f kc Vc VB E Input Answers Power kw Power HP Equation

13 5. Calculate D.O.C. and Power requirement for T03, nd Set-up D.O.C.= P3 P&P7 P6&P11 P30 P6&P31 P&P7 P18&P3 P14&P19 P10&P15 P9 P5&P3 P1&P8 P17&P4 P13&P0 P9&P16 P5&P1 P1 & P8 P4 Depth nd Set-up D= mm N.O.C.= (D-d)/D.O.C./ d= mm N.O.C.= D.O.C.= mm ap * f * kc * Vc P= VB 3 60 *10 * E T03 Power requirement for turning D.O.C. ap = = 0.9 mm ap f kc Vc VB E Input Answers Power kw Power HP Equation Start and Endpoint calculation for T03, 1 st Set-up Z = L B + a + c Rs 13

14 a = b cosα α c = Rs * tan e = X D L=96.0mm c e a Z P6 d=1.5mm do=0mm X=3.634mm d=1.5mm ; do=0.0mm ; L=96.0mm Example for P6&P11: X P6 =3.634mm X D Z P6 = L + b cosα α + Rs * tan Rs = cos * tan 0. 8 = =

15 P17 P14&P18 P10&P15 P6&P11 P13&P19 P9&P16 P5&P1 P1&P8 P4 P&P7 P3 X/ X Z P1 & P P & P P P P5 & P P6 & P P9 & P P10 & P P13 & P P14 & P P

16 6. Start and Endpoint calculation for T03, nd Set-up D.O.C.= P3 P&P7 P6&P11 P30 P6&P31 P&P7 P18&P3 P14&P19 P10&P15 P9 P5&P3 P1&P8 P17&P4 P13&P0 P9&P16 P5&P1 P1 & P8 P4 Depth Xo= GEOMETRIC FIGURE for taper with allowance of material (b) G F g B A b Z Rs Xo X L Zo Z = L F + G + g Rs 16

17 A= Zo * tanα B=A- X Xo F= B tanα G= b sinα g= Rs tan α Example for P&P7: X=0.853 ; Xo=0.0 ; Zo=30.0 ; L=100.0 A= 30 * tan10 = B=A- 0.5 G= sin =.8794 g= 0.5 tan = = F= B = tanα P&P7: Z = = X/ X Z P1 & P P & P P P P5 & P P6 & P P9 & P P10 & P P13 & P P14 & P P17 & P P18 & P P1 & P P & P P5 & P P6 & P P P

18 P18&P3 P-inters. P-intersection: X9.036 Z Calculate for both set-up s the tool nose radius compensation calculation for the internal finishing tool T04. Show the geometry for all points. P1 P3 P.5mm Drill diam. 0 do=1.5mm 100mm Z Z L=10.5mm P 4 X X Rs P1 D=do+(4.0+.5)=34.5mm α 45 K = = 5. 75mm Z = X = Rs * tan = 0.4* tan = mm X = D X + Rs = 34.5 (0.166) = Z = 10. 5mm P1: ( ) ( ) ( ) mm P: Z = L K + Z Rs = = mm X = do = 1. 5mm P3: X = 1. 5mm Z = 70. 0mm 18

19 P1 P P3 W P1: X = Xc + ( Rs) = (0.4) = mm Z = mm P: Z = L R + Z Rs = = mm X = Xc Z + Rs = (.364) + (0.4) = mm L R=.0 Zc Z Rs=0.4 P X X Xc= ( R + Rs) sin = ( + 0.4) sin10 = 0. mm ( R + Rs) cos = ( + 0.4) cos10 =. mm Z = α 417 X = α 364 Z P3: X = 0. 0mm Z = H + Z Rs = = mm Z H=30.0 α 10 Z = Rs * sin = 0.4sin = mm X=0.0 Z P3 19

20 8. Calculate the N.O.C. (number of cuts) and the programming values in X-direction for the threading tool, using the following depth: 0.35mm, 1 0.5mm, mm, 1 0.1mm and mm. Repead the last cut twice at the diameter 4mm. ap X xmin Calculate for both set-up s all start and endpoints for the external finishing tool (T06) with tool nose radius compensation. Show the geometry for all points. 1 st Set-up P1: X=.0mm Z=100.0mm P: X48.931mm P3: X50.0mm Z=99.466mm P4: Z=8.0mm P5: X55.0mm P5 P4 Safety distance mm P3 P P1 W 0

21 X1= d X = D b X Z = L a Z X1 = Rs*tan α = 45 X = Rs Rs 90 Z = Rs*tan α α *tan 90 α Point 1 D L Rs a Angle b Safety tan 0 to input X X = Z result result X X result Z Z nd Set-up P1: X=35.mm Z=100.0mm P: X=40.0mm Z=97.6mm P3: Z=70.0mm P4: X=47.531mm P5: X=50.0mm Z=68.766mm P6: X=54.0mm Z=66.766mm 1

22 Safety distance mm P6 P5 P4 P3 P P1 W X1= d X = D b X Z = L a Z X1 = Rs*tan α = 45 X = Rs Rs 90 Z = Rs*tan α α *tan 90 α Point 4&5 D L Rs a Angle b Safety tan 0 to input X X = Z result result X X result Z Z

23 10. Calculate the feed rates for the finishing tools, based on the required surface finish. f Rth * Rs Rth = f = for Rth = 8µ m 8* Rs 15 f 8* 0.4 = = mm rev for Rth = 16µ m f 16*0.4 3 mm = = rev 11. CNC-Program O005-A % O005 N001 G00 G8 U0.0 W0.0 N00 G99 G1 N003 G50 X Z S3500 N004 G00 T0100 N005 G00 Z178. N006 X300.0 N007 G50 X300.0 Z178. S3500 N008 G96 S10 M04 N009 G40 X59.0 Z100.5 T0101 M08 N010 G01 X-3.0 F0.4 N011 G00 U4.0 W.0 N01 X51.0 N013 G04 X1.5 N014 G01 Z8.0 N015 X55.0 N016 G00 Z10.5 N017 X N018 G01 X51.0 Z99.04 N019 G00 X00.0 M09 N00 X300.0 Z178. T0100 M05 N01 G00 U0.0 W0.0 T00 N0 G50 X300.0 Z15.0 S3500 N03 G97 S143 M03 N04 G00 X0.0 Z10.5 M08 N05 G01 Z70.0 F0.1 N06 G00 Z10.5 N07 X00.0 M09 N08 X300.0 Z15.0 T000 M05 N09 G00 U0.0 W0.0 T0303 N030 G50 X314.8 Z151.0 S3500 N031 G96 S40 M04 N03 G00 X1.817 Z10.5 M08 N033 G01 Z F0. N034 X0.0 Z N035 G00 Z10.5 N036 X3.634 N037 G01 Z N038 X1.817 Z N039 G00 Z10.5 N040 X5.451 N041 G01 Z98.14 N04 X3.634 Z N043 G00 Z10.5 N044 X7.69 N045 G01 Z99.13 N046 X5.451 Z98.14 N047 G00 Z10.5 N048 X34.03 N049 G01 X7.69 Z99.13 N050 G00 Z10.5 N051 X00.0 M09 3

24 N05 X314.8 Z151.0 T0300 M05 N053 G00 U0.0 W0.0 T0404 N054 G50 X315.7 Z147.3 S3500 N055 G96 S50 M04 N056 G00 X Z10.5 M08 N057 G01 X1.5 Z F0.3 N058 Z70.0 N059 X0.0 N060 G00 Z10.5 N061 X00.0 M09 N06 X314.8 Z151.0 M05 N063 G00 U0.0 W0.0 T0505 N064 G50 X35.4 Z139.0 S3500 N065 G97 S300 M04 N066 G00 X0.0 Z105.0 N067 X0.0 Z75.0 N068 G00 G9 X. Z105.0 F.500 N069 X.9 N070 X3.4 N071 X3.7 N07 X3.9 N073 X4.0 N074 X4.0 N075 X4.0 N076 G00 Z10.5 N077 X00.0 M09 N078 X35.4 Z139.0 T0500 M05 N079 G00 U0.0 W0.0 T0606 N080 G50 X96.8 Z177.9 S3500 N081 G96 S150 M04 N08 G00 X.0 Z10.5 M08 N083 G01 Z100.0 F0.3 N084 X N085 X50.0 Z N086 Z8.0 F0.16 N087 X55.0 F0.3 N088 G00 X00.0 M09 N089 X96.8 Z177.9 T0600 M05 N090 G8 U0.0 W0.0 N091 M30 % 11. CNC-Program O005-B % O005-B N001 G00 G8 U0.0 W0.0 N00 G99 G1 N003 G50 X Z5.89 S3500 N004 G00 T0100 N005 G00 Z178. N006 X300.0 N007 G50 X300.0 Z178. S3500 N008 G96 S10 M04 N009 G40 X59.0 Z100.5 T0101 M08 N010 G01 X-3.0 F0.4 N011 G00 U4.0 W.0 N01 X5. N013 G04 X1.5 N014 G01 Z70.5 N015 X55.0 N016 G00 Z10.5 N017 X49.4 N018 G01 Z70.5 N019 X50.0 Z69.00 N00 X5. Z70.5 4

25 N01 G00 Z10.5 N0 X46.6 N03 G01 Z70.5 N04 X Z70.5 N05 X49.4 N06 G00 Z10.5 N07 X43.8 N08 G01 Z70.5 N09 X46.6 N030 G00 Z10.5 N031 X41.0 N03 G01 Z70.5 N033 X43.8 N034 G00 Z10.5 N035 X33.6 N036 G01 Z100.5 N037 G03 X41.0 Z96.8 R3.7 N038 G00 X00.0 M09 N039 X300.0 Z178. T0100 M05 N040 G00 U0.0 W0.0 T00 N041 G50 X300.0 Z15.0 S3500 N04 G97 S143 M03 N043 G00 X0.0 Z10.5 M08 N044 G01 Z50.0 F0.1 N045 G00 Z10.5 N046 X00.0 M09 N047 X300.0 Z15.0 T000 M05 N048 G00 U0.0 W0.0 T0303 N049 G50 X314.8 Z151.0 S3500 N050 G96 S40 M04 N051 G00 X0.853 Z10.5 M08 N05 G01 Z74.57 F0. N053 X19.4 Z70.0 N054 G00 X Z10.5 N055 X.7 N056 G01 Z N057 X0.853 Z N058 G00 Z10.5 N059 X4.591 N060 G01 Z N061 X.7 Z N06 G00 Z10.5 N063 X6.460 N064 G01 Z N065 X4.591 Z N066 G00 Z10.5 N067 X8.39 N068 G01 Z N069 X6.460 Z N070 G00 Z10.5 N071 X N07 G01 Z N073 G0 X9.036 Z R3.3 N074 G01 X8.39 Z N075 G00 Z10.5 N076 X3.067 N077 G01 Z N078 G0 X Z R3.3 N079 G00 Z10.5 N080 X N081 G01 Z100.5 N08 G0 X3.067 Z R3.3 N083 G00 Z10.5 N084 X00.0 M09 N085 X314.8 Z151.0 T0300 M05 N086 G00 U0.0 W0.0 T0404 N087 G50 X315.7 Z147.3 S3500 5

26 N088 G96 S50 M04 N089 G00 X40.0 Z10.5 M08 N090 G01 X Z100.0 F0.16 N091 G0 X Z R.4 N09 G01 X0.0 Z N093 G00 Z10.5 N094 X00.0 M09 N095 X314.8 Z151.0 M05 N096 G00 U0.0 W0.0 T0606 N097 G50 X96.8 Z177.9 S3500 N098 G96 S150 M04 N099 G00 X30.0 Z10.5 M08 N100 G01 Z100.0 F0.3 N101 X35.8 N10 G03 X40.0 Z97.6 R.4 N103 G01 Z70.0 F0.16 N104 X F0.3 N105 X54.0 Z N106 G00 X00.0 M09 N107 X96.8 Z177.9 T0600 M05 N108 G8 U0.0 W0.0 N109 M30 % 1. Calculate the expected tool life for T01. The following paramers for the insert KC850 are known from an exponent table: C=198, F=-0.1, E=-0.34, G=-0.14 T Vc = F C * ap * f E 1 G T01 Tool life calculation Answers ap f Vc Exponent Table Tool life (mm) (mm/rev) (m/min) C F E G min Input ap^f= f^e= /G=

27 13. Calculate the machining rate C and the hourly rate for the CNC lathe. Cw + Ci + Cs + Ce + Cm + Co C = Tu ($/hour) Example: Mean interest 8% Wages $18.0 hour Replacement cost $ 7, Tu Utilization time 10 years, eight hour shifts a day, 5 days a week for 5 weeks each year (50 hours/year) Cs = Cost for space $ year Ce = Cost for energy, efficiency = HP = (0.7457*1) = KW, $0.18KW hour. = $ hours KW * = $ 8, year KWhour year * 0.8 Cm = Cost for maintenance and repair $, per year Co = Other cost (Insurance and Tool cost) $ 4, year Cw= Calculate write off for 6 years ( $/year ) Interest 8% Utilization time 6 years Depreciation per year Remaining value Cw= Re placement cos t Utilization time RV = Sv - Cw = 7,000 6 = $1, Mean value Mv = Sv - [ Cw/ ] = 7,000 - (1,000/) = $66, Interest = [ Mv * Interestrate ] / 100 7

28 Year Sv Mv Rv Interest Remaining f(mean Start Value Mean Value Value Value) 1 7, , , , , , , , , , , , , , ,000.00, , , , , , , ,80.00 Ci = Interest per year = = $, Interest 17,80.00 Cw + Ci + Cs + Ce + Cm + Co C = Tu ($/hour) 1, , , , , , C = = $ 7.51/ hour 4160hrs 11b. Fixed hourly rate for machining Wages Machining rate $ hour C = $ 7.51 hour $ 5.91 hour $ 5.91 hour Calculate the average hourly shop rate for machining : 1 Foreman for 60 workers = 1 x $.00 hour = $.00 / 60 workers= $ hour $ 0.37 hour $ 6.8 hour Overhead cost for administration and engineering department could be 40 to 160% 65 % $ hour $ hour Hourly rate $

29 14. Find the process time for the circular band saw From table 7 tr = 5 min te = 1.8 min 15a. Find the process time for the CNC-Lathe (1 st set-up) Material weight: D=55 mm ; L=104 mm m = 1.94 Kg <.5 Kg The cutting time for each tool is minutes. Tool # Tool # 0.3 Tool #3 0.8 Tool #4 0. Tool # Tool # The total cutting time is... The rapid traverse time is... The total tool change time is.. The total dwell time is....8 min min min min. The overall production time is. ttu =.95 min. Chucking time ttb = 0.3 min tg = ttu + ttb = 3.5 min. tv = 10% of tg = 0.35min te = tg + tv = 3.575min. te = min Set-up time: Load Program 3.00 min Set up 3-Jaw chuck 5.00 min Dry run (3xtg) = (3x3.5) 9.75 min Set-up tool blocks (6x4min) 4.00 min min tr = 4 min 15b. Find the process time for the CNC-Lathe ( nd set-up) The cutting time for each tool is minutes. Tool # Tool # 0.37 Tool #3 1. Tool # Tool #6 0.1 The total cutting time is... The rapid traverse time is... The total tool change time is.. The total dwell time is min min min min. The overall production time is. ttu = 3.30 min. Chucking time ttb = 0.3 min tg = ttu + ttb = 3.60 min. tv = 10% of tg = 0.36 min te = tg + tv = min. te = min 9

30 Set up time for machining operation : Load Program Set up 3-Jaw chuck Dry run (3xtg) = (3x3.6) 3.00 min 5.00 min min min tr = 19 min 16. Fill in a Job card Date: Description: ROLLER Part Number: Jan. 005 Name: Material: 4CrMo4V Quantity: 1000 Dimensions: mm Seq. No. Work Center Text, Fixture, Jig, Tool tr te 5 Saw Cut off barstock L=104mm CNC-Lathe Set-up CNC Late for 1st Set-up CNC-Lathe Set-up CNC Late for nd Set-up Inspection Total Process Time T= 941 min 18. Tabulate the total process cost L $/foot m tr te h/rate T Cost mm min min $ min $ Material $8,805.1 Saw $78.08 CNC Lathe 1st $,6.37 CNC Lathe nd $,904.3 Total 941 $15, hours 30

M A N U F A C T U R I N G P R O C E S S E S ME A S S I G N M E N T 2010

M A N U F A C T U R I N G P R O C E S S E S ME 38.3 A S S I G N M E N T 010 H.- J. Steinmetz, Jan. 010 A machine shop has 15 workers and one shop foreman. The shop has to manufacture a quantity of 1500