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Progettazione di Materiali e Processi

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  1. Progettazione diMateriali e Processi Università degli Studi di Trieste Facoltà di Ingegneria Corso di Laurea in Ingegneria Chimica e dei Materiali A.A. 2016-2017

  2. Programma del corso (1) Progettazione e selezione di materiali e processi (5 crediti) - Lughi Introduzione: Materiali come opportunità nel progetto; dati e strumenti per la progettazione; sommario delle principali famiglie di proprietà dei materiali. Selezione dei materiali: Indici dei materiali e indici strutturali; uso dei diagrammi di Ashby; selezione con obiettivi e vincoli multipli; selezione di materiali e forme; materiali ibridi; casi di studio. Utilizzo del programma CES. Cenni alla selezione di processi. Introduzione alla selezione dei materiali con vincoli ambientali. Esempi di design avanzato: metamateriali; bandgapengineering; materiali ibridi Processeconomics Design tools: Finite Elements Analysis Seminars and visits:Visit to LAMA laboratory; Seminar on Industrial Design (Prof. Paternich)

  3. Calendario secondo semestre Lughi: 20/2 22/2 27/2 1/3 6/3 8/3 Seconda metà di marzo: Visita LAMA Seminari: TBD Fermeglia: 27/3 29/3 3/4 5/4 10/4 12/4 24/4 26/4

  4. Modalità d’Esame • Per passare l’esame serve aver fatto: • Verifiche ed esercizi(passa/non passa) • Progetto-tesina finale: • Presentazione di un progetto-tesina su uno degli argomenti del corso; tema da concordare con uno dei docenti del corso a scelta dello studente • La tesina viene valutata dal docente che ha seguito la tesina e vale come esame finale • Il voto del progetto-tesina determina il voto dell’esame • L’esame viene registrato con il prof. Lughi

  5. ProcessEconomics • Comparative choice of processaccording to costcriteria (done) • Estimate of the overallprocesseconomics • Capital cost • Operationcost • Profitability

  6. Comparative choice of processaccording to costcriteria

  7. Assessing potential: cost and value Inputs to a cost model for selection The model and its implementation Cost drivers, batch size, assembly Cost Modeling for Materials Selection

  8. The real requirement is Cost < Price < Value C < P < V Cost, price and value • Cost = what it actually costs to make the part or product • Price= the sum you sell it for • Value = the worth the consumer puts on the product To maximize profit, P - C we seek to minimize C “Not worth the price” means P > V “Good value for money” means P < V The cost of producing a component or product is made up of • the material cost • the cost of manufacture

  9. 40000 30000 20000 10000 Factor 4 $ per tonne Factor 3 $ per tonne $ per tonne $ per tonne Factor 1.6 Factor 1.7 0il The problem of material price Changing price of materials 2005 - 2007 The need: Cost modeling for material selection 40000 30000 20000 10000

  10. Cost estimate for competitive bidding -- absolute cost is wanted, to Materials Energy Capital Manufacturing process Time Product All have an associated cost Information Estimating cost When alternative material-process combinations meet the constraints, it is logical to rank them bycost • Cost estimate for ranking -- a relative cost is OK – but need generality Generic inputs to any manufacturing process:

  11. Resource Symbol Unit Materials including consumables Cm $/kg Capital cost of equipment Cc $ cost of tooling Ct $ Time (including labor) overhead rate $/hr Energycost of energy Ce $/hr Space, admin.a cost/hr $/hr Information R & D $/hr royalties, licenses Lump into overhead rate Inputs to a generic cost estimator Generic = can be applied to any process

  12. Materials Material costs Cmper kg, mass mper unit; f is the scrap fraction Tooling Ctis “dedicated” -- written off against the number of parts made, n Rate of production Capital cost Cc of equipment is “non-dedicated” written off against time. Capital write-off time is two. Rate of production isunits/hour. The load factor (fraction of time the equipment is used) is L. Gross overhead rate contributes a cost per unit of time that, like capital, depends on production rate Capital, Labor, Information, Energy... Tooling Batch size The cost per unit of output

  13. Tooling costs dominate Material and labor costs dominate LP casting Sand casting Die casting Features of a cost model Casting alloy con-rod • Identify most economic process • Examine materials-cost sensitivity • Explore alternative materials and processes

  14. Desired batch size Economic batch size

  15. Where do you get the input information? • Material and process costs vary with time and depend on the quantity you order • CES EduPack has approximate cost for 3800 materials, regularly updated • Web helps with commodity material prices • American Metal Market On-line, www.amm.com • Iron & Steel Statistics Bureau, www.issb.co.uk • Kitco Metals Inc Gold & Precious Metal Prices. www.kitco.com/charts/livegold.html • London Metal Exchange, www.lme.co.uk • Metal Bulletin, www.metalbulletin.com • Mineral-Resource, www.minerals.usgs.gov • The Precious Metal and Gem Connection, www.thebulliondesk.com • Ask suppliers: but how find them? • Thomas Register of European Manufacturers, TREM • Thomas Register of North American Manufacturers • Kelly’s register, www.kellysearch.com

  16. Characteristics of the process Cost of equipment Cc Cost of tooling Ct Production rate The database has approximate value-ranges for these Site-specific, user defined parameters Batch size n Mass of component m Capital write-off time two Load factor L Overhead rate These are entered by the user via a dialog box Cost modelling in CES

  17. fx Dialog box Capital write-off time two = …. Component mass m = …. Load factor L = …. Material cost Cm= Overhead rate = …. Graph Relative cost Batch size Cost model Cost modeling Relative cost index (per unit) 5 - 6 Capital cost 2000 - 5000 GBP Material utilisation factor 0.7 - 0.75 Production rate (units) 20 - 30 per hr. Tooling cost 300 - 450 GBP Tooling life 5000 - 10000 units

  18. Cost model

  19. Estimate of the overallprocesseconomics

  20. Cost challenges for process engineers • How much do we need to build a new chemical manufacturing plant? • estimation of capital investments • How much does it cost to operate a chemical plant? • estimation of total product costs • How can we estimate the economic value of making modifications to an existing chemical manufacturing plant? • How can we select a “best process” from competing alternatives? • estimation of process profitability

  21. net profit after taxes U = (1– t )(R – C’ – d ) income taxes T = t (R – C’ – d ) t is 35÷45% of U’’ gross profit U’’ = R – C’ – d d depreciation charge gross profit before depreciation U’ = R – C’ net cash flow CF = = (1– t )(R – C’ – d ) + d = (1– t )(R – C’ ) + t  d C’ total product cost (excluding depreciation) R revenues Process operations St, startup capital WC, working capital TCIL = FCIL + WC + St Generation of cash flow from an industrial process FCIL fixed capital repayment of borrowed capital TCI, total capital investment, (without land) other investments stockholders’ dividends Capital source and sink Loans bonds & other capital input preferred stock common stock

  22. 1. Capital investment

  23. Total capital investment • When a new plant needs to be built, the required total capital investment (TCI) does not result only from the cost of equipment • Fixed capital investment • direct and indirect costs required to build the plant • not related to production/operation • Turnover time is long (law says more than 1 year) • Working capital investment • capital required to actually operate the plant • Start-up costs • capital required to startup the the plant for the first time

  24. Total capital investment (TCI) Fixed capital (FCI) Working capital Start-up manufacturing capital inv. Direct costs Indirect costs nonmanufacturing capital inv. onsite (ISBL) offsite (OSBL) Breakdown of total capital investment & startup costs • process modifications • start-up labor • loss in production 8÷10% FCI • buildings • process buildings • auxiliary buildings • maintenance shops • building services • yard improvements • railroad sidings; roads; sidewalks • fencing; landscaping • service facilities • utilities • facilities • nonprocess equipment • distribution & packaging • land 6÷20% FCI • engineering & supervision • construction expenses • temporary facilities • construction tools & equipment • construction supervision • warehaouse personnel and guards • safety, medical, and fringe benefits • permits, field tests, special licenses • taxes, insurance, and interest • contractor’s fee • contingencies 15÷30% FCI • raw materials (~1 month) • finished products • accounts receivable • cash on hand • salaries & wages • raw-material purchases • accounts payable • taxes payable 10÷20% TCI • purchased equipment • purchased equipment installation • instrumentation & control • piping • electrical equipment & material 50÷60% FCI

  25. Project cost & influence of design decisions • As a project proceeds from initial concept through detailed design to startup: • Costs begin to be accumulated, particularly once procurement and construction get underway • The ability of the design engineer to influence project cost decreases

  26. Amount of information needed to provide the estimate Accuracy of estimate Estimation of the capital investment • Classification and accuracy of capital cost estimates: • order-of-magnitudebetween +40% and –20% • studybetween +30% and –20% • preliminary designbetween +25% and –15% • definitivebetween +15% and –7% • detailedbetween +6% and –4%

  27. The cost of making a cost estimate • Improving a costesimateisitself a cost! • the man hours required to provide the estimate increase with the accuracy of the estimate (Turton et al., 1998) (Ulrich & Vasudevan, 2004)

  28. Choosing the appropriate estimate • When a new processhas to be designed, oneoftenhas to screen for several(tenths of)alternatives • each alternative differs for the number and/or type of pieces of equipment, and/or for the energyrequirements • The selectionprocessisdriven by twoguidelines • To proceed with the study of a new process, the process must be: • technically sound • economicallyattractive • Whenseveralalternatives are to be screened, quickevaluations of costestimates are sought for, in order to be able to provide a fast and sound evaluation of the alternatives • Order-of-magnitudeestimates are usuallyenough for thispurpose

  29. A model for the estimationofTotal Capital Investment(TCI) • A few sound hypotheses(Douglas, 1988): • startup costs 10% FCI • working capital  15% TCI • off-site directcosts (OSBL)  45% on-site directcosts (ISBL) • indirectcosts  25% directcosts (ISBL+OSBL) • includescontingencies  20% directcosts Onsite direct costs (ISBL): • purchased equipment • purchased equipment installation • instrumentation & control • piping • electrical equipment & material To get a quick estimate of the total capital need, it is sufficient to provide an esimate of the installed equipment costs!

  30. Estimation of equipmentcosts Onsite direct costs (ISBL): • purchased equipment • purchased equipment installation • instrumentation & control • piping • electrical equipment & material • Equipment costs are the major costs associated with the onsite direct costs • An accurate estimate can only be obtained from a vendor’s quote • We do not want to get a vendor’s quote for each process alternative that we are screening! • Generalized correlations (equations or graphical printouts) are sufficient for order-of-magnitude estimates • each time we use a generalized correlation, we must update the estimate to take care of: • equipment capacity • time elapased between when the correlation was developed and when it is used (inflation)

  31. The effect of capacity on purcahsingcost  • The capacity of a piece of equipment affects the purchased cost, but not in a linear way A = cost attribute of the equipment C = purchased cost n = cost exponent (n 0.44÷0.70) a = equipment whose cost is to be estimated b = equipment with reference capacity economy of scale • It is often assumed that n = 0.6 (six-tenths rule) Example: centrifugal blower

  32. The effect of time on purcahsingcost C = purchased cost I = cost index 1 = “reference” year at which the cost is known 2 = year at which the estimate is needed • The purchased cost on a certain year must be updated with respect of the purchased cost of the same piece of equimpment in a previous year because of inflation • Cost indices are available, which are calculated from a “basket” of pieces of equipment • Marshall & Swift Process Industry Cost index (M&S) • 1926 value = 100 • 2005 value = ~1250 • Chemical Engineering Plant Cost Index (CEPCI) • 1957 value = 100 • Nelson-Farrar Refinery Construction Index • 1946 value = 100 • Engineering News Record Construction Index • 1967 value= 100

  33. Marshall e Swift index cost exponent:economy of scale Fc = correction factor (type of equipment; design pressure; materials of construction) Example: estimating the purchasedcost of a heatexchanger(Guthrie’scorrelations) cost attribute: A = exchange area [ft2] Cinst accounts for all onsite costs related to the equipment that needs installing: • purchase of the equipment • installation • instrumentation and conventional control • piping: insulation and paint • auxiliary electrical equipment (example for year 2006: fixed head exchanger, 100 m2, CS, low P: purch. equipm. cost  130,000 $)

  34. Total capital investment (TCI) manufacturing capital inv. Fixed capital (FCI) Working capital Start-up Direct costs Indirect costs nonmanufacturing capital inv. onsite (ISBL) offsite (OSBL) Breakdown of total capital investment & startup costs • process modifications • start-up labor • loss in production 8÷10% FCI • buildings • process buildings • auxiliary buildings • maintenance shops • building services • yard improvements • railroad sidings; roads; sidewalks • fencing; landscaping • service facilities • utilities • facilities • nonprocess equipment • distribution & packaging • land 6÷20% FCI • engineering & supervision • construction expenses • temporary facilities • construction tools & equipment • construction supervision • warehaouse personnel and guards • safety, medical, and fringe benefits • permits, field tests, special licenses • taxes, insurance, and interest • contractor’s fee • contingencies 15÷30% FCI • raw materials (~1 month) • finished products • accounts receivable • cash on hand • salaries & wages • raw-material purchases • accounts payable • taxes payable 10÷20% TCI • purchased equipment • purchased equipment installation • instrumentation & control • piping • electrical equipment & material 50÷60% FCI

  35. 2. Total productcost

  36. net profit after taxes U = (1– t )(R – C’ – d ) income taxes T = t (R – C’ – d ) t is 35÷45% of U’’ gross profit U’’ = R – C’ – d d depreciation charge gross profit before depreciation U’ = R – C’ net cash flow CF = = (1– t )(R – C’ – d ) + d = (1– t )(R – C’ ) + t  d C’ total product cost (excluding depreciation) R revenues Process operations St, startup capital WC, working capital TCIL = FCIL + WC + St Generation of cash flow from an industrial process FCIL fixed capital repayment of borrowed capital TCI, total capital investment, (without land) other investments stockholders’ dividends Capital source and sink Loans bonds & other capital input preferred stock common stock

  37. Total product cost (TPC) manufacturing cost (operating or production costs) general expenses (SARE) (Sales, Administr., Research, Engng) direct production costs (variable production costs) fixed charges plant overhead Breakdown of totalproductcost • depreciation • local taxes • insurance • rent • interest 10÷20% TPC • administrative costs (2÷5% TPC) • executive salaries • clerical wages • legal fees • office supplies • communication • distribution & selling costs (2÷20% TPC) • sales offices • sales staff • shipping • advertising • research & development (5% TPC) 2.5% revenues • raw materials • utilities • electricity • fuel • refrigeration • steam • waste treatment & disposal • process water • cooling water • maintenance & repairs • operating supplies & laboratory charges • operating labor • direct supervision & clerical labor • patents & royalties 60% TPC • general plant upkeep & overhead • payroll overhead • social security • retirement plans • packaging • medical services • safety & property protection • restaurants & recreation facilities • storage facilities 5÷15% TPC

  38. A model for the estimationofTotal Product Cost(TPC) • A few (sound) hypotheses (Douglas, 1988) • SARE  2.5% of revenues • maintenance  4% FCI each year • cost of operating labor:  105 $/(operator×year) • no borrowed capital; no expenses for land • no depreciation allowance (so far) All numeric coefficients have proper unit dimension • To be able to provide and estimate of the total product cost, we need to determine: • amount of raw materials needed • utilities consumption • installed costs for all the pieces of equipment • total number of operators needed to run the plant • revenues from product sales

  39. Evaluation of utility costs • Utilities are service streams (material and energy) required to run the plant • most of the utility streams are used to exchange energy (heat) with the process streams • therefore one needs to evaluate the energy requirements and costs • Utility costs are affected by fuel costs, hence by oil costs • Fuel oil costs vary in a much more erratic way than inflation (e.g. CEPCI index) • Coal has the lowest cost and the most stable trend • however, it may be very polluting

  40. Typical costs of utilities in Italy

  41. 3. Processprofitability

  42. net profit after taxes U = (1– t )(R – C’ – d ) income taxes T = t (R – C’ – d ) t is 35÷45% of U’’ gross profit U’’ = R – C’ – d d depreciation charge gross profit before depreciation U’ = R – C’ net cash flow CF = = (1– t )(R – C’ – d ) + d = (1– t )(R – C’ ) + t  d C’ total product cost (excluding depreciation) R revenues Process operations St, startup capital WC, working capital TCIL = FCIL + WC + St Generation of cash flow from an industrial process FCIL fixed capital repayment of borrowed capital TCI, total capital investment, (without land) other investments stockholders’ dividends Capital source and sink Loans bonds & other capital input preferred stock common stock

  43. Depreciation of capital investment • The value of a plant decreases with time • physical depreciation: : deterioration due to usage, corrosion, accidents,… • functional depreciation : technological obsolescence, change in legislation, insufficient capacity • land does not depreciate (usually) • When the plant is closed, the plant equipment can be salvaged and sold, but for only a fraction of the original cost • capital depreciation is the difference between the original cost (FCI) and the salvage value (S) • Tax legislation allows only a fraction of the capital depreciation to be charged as an operating expense each year, until the total depreciation has been charged • this yearly amount is the depreciation expense (depreciation charge)

  44. Depreciationmethods • Straight line method, SL: • an equalamount of depreciationischargedeachyear over the depreciationperiodallowed • Double declining balance method, DDB: an accelerated method  • Modified accelerated cost recovery system, MACRS • Generally speaking, it is convenient to depreciate an invested capital as soos as possible • the sooner we can save on tax expenses, the earlier we can start to re-invest this money we have saved • a typical assumption for screening calculations: SL depreciation method, with a 10-year plant life • Depreciation plans are strictly regulated by taxation legislation

  45. net profit after taxes U = (1– t )(R – C’ – d ) income taxes T = t (R – C’ – d ) t is 35÷45% of U’’ gross profit U’’ = R – C’ – d d depreciation charge gross profit before depreciation U’ = R – C’ net cash flow CF = = (1– t )(R – C’ – d ) + d = (1– t )(R – C’ ) + td C’ total product cost (excluding depreciation) R revenues Process operations St, startup capital WC, working capital TCIL = FCIL + WC + St Generation of cash flow from an industrial process FCIL fixed capital repayment of borrowed capital TCI, total capital investment, (without land) other investments stockholders’ dividends Capital source and sink Loans bonds & other capital input preferred stock common stock

  46. Profitability analysis • fsfdsfs

  47. Profitability analysis Some issues need attention in order to carry out a profitability analysis on an existing process (or on a process to be designed anew) • Capital investment is done once and for all at “time zero”(or possibly on in the first 2-3 years), while manufacturing costs appear on a yearly basis • Regardless of inflation, does the “value” attributed to investments and costs change as time progresses? • How can we compare costs and revenues, which are expressed in ($/yr), to investments, which are expressed in ($)?

  48. The time value of money • For an investor, a certain amount of money, owned “now”, has a value that is different from the one that the same amount will have “in the future” • the time going from “now” to “the future” can be used to invest the sum, so as to have a larger sum in “the future” (money ) + (time )  (more money ) • therefore, the present value (or “principal”) P has, now, a higher value than the one that the same sum P of money has n years ahead from now • this is know as the time value of money • the capability of money to generate profit decreases with time • this is independent of inflation, which decreases the purchasing power of money, but not the capability to generate profit

  49. dollars compounding discounting years 0 n Discounting and compounding • Cash flows appear at (the end of) different years during the life of a plant • they can be negative (investments; expenses) or positive (revenues) • To compare these cash flows, they must be put on the same basis, i.e. they must be referred to the same year in time (forward or backward) • The concept of interest is used to move forth and back in time • compounding • discounting • Interest represents the earnings on money loaned (and invested) • also the cost of borrowed money is called interest • The interest rate is the amount of money earned on 1 $ in 1 year • this is the investor point of view

  50. Discounting and compounding • To put all the sums on the same time basis: • at the end of each year in the life of a plant, the relavant cash flow is evaluated • then this cash flow is either discounted back to “year zero” or compounded forth to the “end of life” of the project • discounting is more frequent than compounding for evaluation of process profitability • This procedure has two advantages: • all the sums of money are referred to the same year, i.e. to the same capability to generate profit  the comparison is fair • we can analize investments together with revenues/expenses, because all the sums of money are expressed in [$-at-the-end-of-a-certain-year]