Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:1 Environmentally Conscious Design & Manufacturing Class 14: Cost Factors in Machining Operations Prof. S. M. Pandit

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:2 Manufacturing Economics & the Environment Life cycle view l Raw material l Manufacturing èDesign èProduction (Scheduling, Planning, Machining) l Use l Post-use è Materials handling è Energy production

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:3 Manufacturing Economics & the Environment Product Life Cycle Use Power Generation “Waste” Energy Materials Fluids Post Use Raw Material Extraction Material Handling and Logistics Manufacturing

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:4 Raw Material Design requirements –With/ without environmental considerations –Quality factor Quality deterioration/ improvement Inspection Cost of raw material –Natural (extraction cost) –Man-made (development costs - temporal)

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:5 Post Use Environmental Impact Reuse / Remanufacture / Recycle / Disposal “ Cost ” Material cost Design costs Option chosen

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:6 Material Handling Cost Equipment A B C Tractor truck Forklift truck Hand truck 19 * 203 Item Choice (Design) Manufacturing Facilities Location, Planning and Design D.R. Sule (PWS Kent Publ. Co., 1988) Data from Material & Design choiceAdd to total cost

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:7 Manufacturing Cost Factors Machine Tool Machining – Process parameters wear rate – Tool / Workpiece interaction Work (job) chips Tool wear / failure debris – Fluid use mist, disposal Process scheduling energy use Production planning productivity factors

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:8 Machining Costs Machine Tool – Power requirements – Initial costs – Depreciation – Flexibility – Maintenance – Expected use

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:9 Machining Costs Process parameters – Speed – Feed – Depth of cut Power=Feed Rate(Feed Force+Friction Force)/ (  Mech *  Mech ) Engineering Formulas (7th Ed.,1998) K.Gieck & Reiner Gieck., Mc Graw Hill Tool wear Power consumed Tool type Work - piece Fluid application Quality requirements Productivity needed

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:10 Machining Costs Process Parameters – Tool type Insert – Rake, Non - Insert Cutter Type (turning, milling,..) Single point / Multi point / Form tool Material Cost Material, Dry/wet

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:11 Machining Costs – Volume of material removed (m 3 ) – Tool type needed (insert …) – Cutting fluid needed (Y/N, flow rate) Work - piece Cost

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:12 Machining Costs L Volume removed:

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:13 Machining Costs Chips – Continuous (bad) Interferes in machining - Flush with cutting fluid ? – Discontinuous (good) Need to adjust – Work material – Machining parameters – Tool geometry – Dust

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:14 Machining Costs Factors influencing fluid application costs – Type of fluid Synthetic / natural oils / semi-synthetic Straight oils Air / inert gas – Flow rate – Heat transfer requirements – Lubrication & chip transport – Chip adhesion

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:15 Machining Costs Tool – Excessive wear rate v/s cost – Catastrophic failure inclusions in work incorrect parameters shock loading (temperature / load induced)

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:16 Machining Costs Fluid Use – Mist collectors – Pumps and tanks (circulation) – Filtration – Maintenance system – Additives / Initial cost – Disposal (bioremediation / chemical treatment)

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:17 Scheduling L.P. formulation CostEnvironmentQuality Cost Difference

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:18

Environmentally Conscious Design & Manufacturing (ME592) Date: April 5, 2000 Slide:19 Case Study Machining – Tool – Work – Cutting Fluid – Power, labor, m/c tool – Environment ? Cost items Alternative 1Alternative 2