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Ch 7-1 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Cost Analysis and Estimating for Engineering and Management Chapter 7 Operation Estimating
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Ch 7-2 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Overview l Find Time/Cost for Production Steps l Determine Direct Labor Time l Look at a Metal Machining Example Set Up Cycle Time l One Time Tooling Costs l Overview of Flow Line Manufacturing
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Ch 7-3 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Background l “Design” Defines a Part l Design Is Broken Down into Operations l Labor & Material Determined l Cost Estimated
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Ch 7-4 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Definitions l Manufacturing Operations Produce Changes to Objects to Increase Value l Cost For Utilization of Labor & Materials to Increase Value of Some Object
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Ch 7-5 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operation Estimates l Establish Costs for Components and Assemblies l Initiate Cost Reductions l Provide Standards l Compare Different Designs l Support Decisions
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Ch 7-6 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operation Cost Elements
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Ch 7-7 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Industries l Construction Plant and Equipment Output of Industry Value of Output PortableImmobile and unique Expensive
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Ch 7-8 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Industries l Agriculture Plant and Equipment Output of Industry Value of Output MobileMoves off the plant site and is numerous Inexpensive
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Ch 7-9 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Industries l Information and Service Plant and Equipment Output of Industry Value of Output TransitionalTemporaryLow priced
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Ch 7-10 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Industries l Manufacturing Plant and Equipment Output of Industry Value of Output Fixed Moves off the plant site and is numerous Cheap to expensive
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Ch 7-11 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Manufacturing Facts l Average Lot Quantity - 100 Units l Employs 16% of Population l Declining as a Percentage l Still Increasing in Absolute Numbers l Productivity Is Exceedingly High
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Ch 7-12 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Discrete Manufacturing l Mass Production High Volume, Independent of Orders l Moderate Production Large Volume, Connected to Orders, Fluctuates l Job Lot Small Quantities (1-500)
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Ch 7-13 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operation l Series of Elements l Performed at a Single Workstation Machine, Bench, Process l One or More Operations to Complete a Part or Assembly to a Predetermined State (per Drawing/Design)
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Ch 7-14 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Machining l Traditional Metal Cutting l Subject for Remaining Discussion l Set Up Prepare Machine/Process Includes Return to Neutral Condition l Cycle time Run Time to Complete One Unit Repeats
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Ch 7-15 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Classic Operations Analysis
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Ch 7-16 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Classic Operations Analysis
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Ch 7-17 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Modeling Machining Time l Single Point Tool - Turning Operation l Time (Cost) Is Function of: Handling Time Machining Time Tool Changing Time Tool Cost
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Ch 7-18 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Handling Cost l Load and Unload Work l Constant l Not Related to Cutting Time Eq 7.1
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Ch 7-19 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Handling Cost
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Ch 7-20 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Machining Cost l Based on Cutting Speed and Feed l Controlled by Machine Setting l Shape of Part Is Changed Eq 7.2 Eq 7.3
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Ch 7-21 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Machining Cost
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Ch 7-22 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Tool Associated Costs l Tool Cutting Edges Wear l Wear Rate Increases with Speed l Tools Need to be Replaced/Sharpened l Takes Operator’s Time l Apportioned Over Parts Produced
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Ch 7-23 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Tool Changing Cost
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Ch 7-24 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Tool Life l Taylor’s Tool Life Equation l Relates Tool Life to Cutting Speed l Constants Empirically Determined For a Given Set of Conditions Only Eq 7.6
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Ch 7-25 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Determining n and K
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Ch 7-26 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management l Determine Fraction of the Tool Life Used Up on Each Part t m / T l Tool Changing Cost / Part l Tool Cost / Part Apportioning the Tool Costs Eq 7.7 Eq 7.8
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Ch 7-27 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Total Machining Time / Part Eq 7.9
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Ch 7-28 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management l Minimum Machining Cost Maximum Production Output Ignore Tool Cost - Minimize Time Finding Optimum Cost / Time Eq 7.10 Eq 7.12
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Ch 7-29 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operations Analysis l Determine Production Quantity Operations l Divide Operations into Elements l Determine Element Times For Set Up and Cycle From Data Warehouse Add Element Times to Get Operation Time
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Ch 7-30 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operations Sheet l Divides Manufacturing Process into Operations l Specifies: Machines/Locations Sequence Work to Be Done in Each Operation
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Ch 7-31 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Steps for Operations Sheet l Interpret Engineering l Select Work Locations/Equipment l Specify Tools l Partition into Distinct Operations l Describe Each Operation l Present Information
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Ch 7-32 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Example Part
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Ch 7-33 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Example Operations Sheet l Initial Operations Sequence WorkstationOp No.Description Turret lathe10Turn and cutoff Vertical mill20End mill slot Horizontal mill30Slab mill flat NC drill press40Drill and tap holes
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Ch 7-34 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operations Process Plan WorkstationOp. no. Description of operation Setup hr Cycle hr/100 Lot hr Turret lathe10Face 0.015 Turn rough 1.45 Turn rough 1.15 Finish turn 1.10 Turn 1.735 Cutoff to 18.75 Vertical mill20End mill 0.89 slot Horizontal mill30Slab mill 4.75 x 3/8 N.C. turret drill40Drill, tap
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Ch 7-35 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Set Up l Once per Lot l Given in Hours l Select Appropriate Elements DescriptionHr Punch in and out, study drawing 0.2 Turning Equipment First tool1.3 Each additional tool 0.3 Collet0.2 Chuck, fixture0.1
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Ch 7-36 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Handling Time l Select Appropriate Elements l Time in Minutes (Watch Units!) Machine and Element DescriptionMin Turning, milling, drilling Start and stop machine0.08 Change speed of spindle0.04 Inspect dimension with micrometer0.30 Turning equipment Cross slide advance, return, and index0.09 Advance stock through feed tube < 6”0.18
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Ch 7-37 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Machining Time l Majority of Cycle Time (Usually) l Machine Driven (Cutting Feed Rate) l Function of Design/Material Amount of Material to Remove Machine Tool(s) Used Speeds and Feeds
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Ch 7-38 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operation 10 l Set Up (from Table 7.4) A. Setup elementsHr Punch in and out, study drawing 0.2 Collet0.2 First facing tool1.3 Additional 5 tools1.5 Setup total, operation 103.2
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Ch 7-39 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Op 10 - Handling l From Table 7.5 B. Handling Min Start and stop machine0.08 Advance stock0.37 Place and remove oil guard0.19 Speed changes, assume 4 x 0.04 0.16 End turret 5 x 0.080.40 Cross slide advance, return0.09 Inspect part with micrometer, irregular 1/5 x 0.30 0.06 Subtotal of handling and equipment elements 1.35
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Ch 7-40 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Facing Elem Depth of Cut Ld Ld Ls Ls L D V fpm F (ipr) t m, min Face0.0150.8751/32.9061.750350.0070.17
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Ch 7-41 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management First Rough Turn Elem Dim Depth of Cut Ld Ld Ls Ls L D V fpm f (ipr) t m min Rough turn 1.450.1516.5 1/3216.51.75 350.0151.44
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Ch 7-42 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Second Rough Turn Elem Dim Depth of Cut Ld Ld Ls Ls L D V fpm f (ipr) t m min Rough turn 1.150.1516.5 1/3216.51.45 350.0151.19
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Ch 7-43 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Remaining Elements
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Ch 7-44 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Cycle Times for Remaining Elems ElemDimDepth of Cut LdLd LsLs LDV fpm F (ipr) t m, min Finish turn 1.100.02516.51/3216.531.153500072.03 Elem 5 Turn 1.73.00750.51/320.531.753500070.10 Cutoff1.75.8751/320.9061.753500150.08
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Ch 7-45 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operation 10 Totals Subtotal of machining times 5.01 Total cycle time for handling and machining 6.36 D. Entry values for operation sheet, operation 10 Setup hr3.2 Hr/100 units10.600
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Ch 7-46 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Calculating Length of Cut l For Rotating Cutters l Length of Travel at Feed Rate l Safety Length For Stock and Mounting Variations Eq 7.14
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Ch 7-47 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Other Length Factors l Approach/Over Travel Gets Cutter Fully Into & Out of Work Many Times = Cutter Radius but… Over Travel May Not Be Required l Design Length Actual Length Making Cut Include All Passes and Lateral Moves
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Ch 7-48 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management End Mill Length of Cut
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Ch 7-49 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Peripheral Cutting Length
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Ch 7-50 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Approach Length Differs l Peripheral Milling Need to Consider: Cutter Diameter Depth of Cut Eq 7.15
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Ch 7-51 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Drilling l Approach Includes Point Angle Eq 7.16
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Ch 7-52 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operation 20 l Set Up (from Table 7.4) A. Setup elementsHr Punch in and out, study drawing0.2 Slot-cut milling collet1.6 Setup total, operation 201.8
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Ch 7-53 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Handling l From Table 7.5 B. Handling and other equipment time elements Min Start and stop machine0.08 Air clean part0.06 10 lb < 15 lb load into collet 0.25 Open and close air vise0.06 Change speeds and feeds, 2 x0.08 Subtotal of handling0.53
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Ch 7-54 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management End Milling
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Ch 7-55 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management End Milling Times ElementLdLd Milling Cutter V fpm f t (i t pr)t m,, min Rough mill slot 6.810.75 in. end mill, 4 flute 850.0021.97 Finish mill slot 6.810.75 in. end mill, 4 flute 950.00152.34
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Ch 7-56 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operation 20 Totals Subtotal of machining times 4.31 Total cycle time for handling and machining, min 4.84 D. Entry values for operation sheet, operation 20 Setup hr1.8 Hr/100 units8.067
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Ch 7-57 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operation 30 l Set Up (from Table 7.4) A. Setup elementsHr Punch in and out, study drawing 0.2 Special vise1.1 Setup total, operation 301.3
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Ch 7-58 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Handling l From Table 7.5 B. Handling and other equipment time elements Min Start and stop machine0.08 Air clean part0.06 10 lb < 15 lb load into collet fixture 0.25 Open and close air vise0.06 Subtotal of handling and other equipment 0.45
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Ch 7-59 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Peripheral Milling
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Ch 7-60 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management l Peripheral Milling Use Equation 7.15 for Approach and OT Cutter 4” Dia, Depth of Cut = 3/8” l L d = 1.05, L a = L ot = 1.2 (L s in Rounding of L a ) l L = 1.05 + 2(1.2) = 3.45 Length of Cut
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Ch 7-61 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Peripheral Milling Times ElementLdLd Milling Cutter V fpm f t d (i t pr) tmtm Mill flat on end 3.454 in. O.D., 8 tooth 2100.0050.43
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Ch 7-62 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operation 30 Totals Subtotal of machining times 0.43 Total cycle time for handling and machining, min 0.88 D. Entry values for operation sheet, operation 30 Setup hr1.3 Hr/100 units1.467
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Ch 7-63 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operation 40 l Set Up (from Table 7.4) A. Setup elementsHr Punch in and out, study drawing 0.2 First turret station for drill 0.75 Second turret station for tap 0.07 Collet for holding0.1 Setup total, operation 401.12
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Ch 7-64 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Handling l From Table 7.5 B. Handling and other equipment time elements Min Start and stop machine0.08 Air clean part0.06 10 lb < 15 lb load/unload part into collet 0.22 Open and close air collet clamping0.05 Index turret, 2 x for drilling and tapping0.06 Raise tool, move to new locations, 8 x0.48 Subtotal of handling and other equipment0.95
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Ch 7-65 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Drilling
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Ch 7-66 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Drilling Time ToolLdLd f dt Lf dt No. holes t m,, min Drill, 5/160.630.610.3841.52 Tap, 3/8 – 160.50.330.1740.66
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Ch 7-67 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Operation 40 Totals Subtotal of machining times 2.18 Total cycle time for handling and machining, min 3.13 D. Entry values for operation sheet, operation 40 Setup hr1.12 Hr/100 units5.217
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Ch 7-68 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Post All of the Times Op. no. Setup hr Cycle hr/100 units Lot Hr (Qty = 200) 103.210.60024.4 201.88.06717.9 301.31.4672.9 401.125.21710.4
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Ch 7-69 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Tool Cost l Tools Facilitate Manufacturing l Tool Cost Is Part of Operation Cost l Tools – Permanent, One-Time Cost Nonrecurring, Initial Fixed Cost l Tools Require Engineering Design l Tools Can Be a Large Cost
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Ch 7-70 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Tool Cost Estimating l Simple Methods Standard Time Data Use Tables Broad, General Categories l One Time Cost Estimate Less Critical Usually Hours Is the Increment
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Ch 7-71 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Drill Jig Example
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Ch 7-72 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Drill Jig Cost Description of tool elementsHr Angular base plate, C-angle7.0 Guide bushing2.0 Hinge plate12.0 Clamp with screw7.5 Feet, 37.5 Pin locators, 58.8 Total44.8 Productive hour cost for tool making$75 Cost of tool, 44.8 x 75$3360 Material cost, $25/lb200 Total cost of tool$3560
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Ch 7-73 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management What to Do with Tool Costs l Add to Overhead (NOT Recommended) l Amortize Over Production l N Is Critical Too Small N, Tooling Cost Too High Too Large N, Tooling May Not Be Paid For Eq 7.18
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Ch 7-74 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Tooling vs. No Tooling l Compare Manufacturing Cost Using Tooling (Saves Labor) Without Tooling (Additional Labor) Eq 7.19
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Ch 7-75 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Calculate the Operation Cost l Batch Manufacturing Situation l Determine Hours for the Lot l Find the Batch (Lot) Cost Eq 7.20 Eq 7.21
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Ch 7-76 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Total Product Manufacturing Cost l Cost for All Operations l Include Material and Tooling Costs Eq 7.22
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Ch 7-77 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Cost for Pinion Example Op. no. Lot hr PHC Lot cost Unit cost 1024.439.16$955$4.78 2017.990.98$1631$8.16 302.990.98$267$1.34 4010.439.16$409$2.04 $3262 $16.32 $37.66 Total Lot Cost Unit Production Cost Total Unit Cost (incl. $21.43 Matl)
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Ch 7-78 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Flow Line Manufacturing l Mass Production, Assembly Lines l All Operations Interdependent l Times Determined from Station Requiring the Longest Time l Imbalance Leads to Idle Time for Other Stations
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Ch 7-79 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Flow Line Set Up Time l Find Maximum Station Set Up Time l Total Cost for Line Set Up Eq 7.23
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Ch 7-80 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Flow Line Cycle Time l Find Maximum Station Cycle Time l Total Cost for Line Cycle Time Eq 7.24
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Ch 7-81 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Total Product Time (Flow Line) l Determine Lot Hours If nSU f is Very Small Compared to nNH f Set Up Cost Can Be Ignored Covered in Overhead Eq 7.25
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Ch 7-82 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Total Product Cost (Flow Line) l Total Labor Cost l Total Product Cost Eq 7.26 Eq 7.27
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Ch 7-83 © 2004 Pearson Education, Inc. Pearson Prentice Hall, Pearson Education, Upper Saddle River, NJ 07458 Ostwald and McLaren / Cost Analysis and Estimating for Engineering and Management Summary l Determined Costs for Manuf. Operations l Found Direct Labor Times Set Up and Cycle Times Machining Time l Studied a Metal Machining Example l Added Tooling Costs l Briefly Looked at Flow Line Costs
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