Product and Equipment Analysis Chapter 2

Data required for developing good layouts Product Analysis Process Analysis

Input Data and Activities What data are critical to the facility plan? Muther categorizes the information as: P – Product (what?) Q – Quantity (how much?) R – Routing (where?) S – Support (with what?) T – Timing (when?)

Product Analysis Bill of Materials Assembly Charts Engineering Drawing Operation Process Chart Route Sheet QFD product development TRIZ CAD/CAM

Input Data and Activities Tompkins, White, et. al., categorize it as: Product Design – what is to be produced? Process Design – how is it to be produced? Schedule Design – when and how much? Product Facility Process Schedule

Driven by market demand Product Design Based on Function Aesthetics Costs Materials Manufacturing Methods Key point The product design MUST be finalized before designing the facility. Otherwise a flexible facility is needed. Driven by market demand

Tools Used in Product Design Product/Part Drawings 2-D, 3-D visualization Exploded Assembly Diagrams

Part drawing

Tools Used in Process Design A partial list (dependent on product and service): Process Flowcharts and Process Maps Make vs. Buy Parts Lists Bill of Materials Route Sheets Assembly Charts Operations Process Charts Precedence Diagrams

Process Flowcharts Reserve Storage Quality Assurance Back to Vendor UPS Parcel Post Next-Day UPS Mono-gramming Embroid-ering Hemming Gift Boxing Receiving Active Bins Picking Packing Shipping

Give soup or salad order to chef Process Maps Customer Waiter Salad Chef Dinner Chef Is order complete? N Place order Y Give soup or salad order to chef Prepare soup or salad order Give order to waiter Give dinner order to chef Prepare dinner order Drink Get drinks for customer Eat salad or soup Deliver salad or soup order to customer Eat dinner Deliver dinner to customer Give order to waiter Receives check Deliver check to customer Gives payment to waiter Receive payment for meal Credit Cash or Credit? Cash Collect change, leave tip Bring change to customer Run credit card through Fill in tip amount Return credit slip to customer Collect tip

Is it cheaper for us to make? Is the capital available? Make vs. Buy? BUY No Yes Can we make the item? Is it cheaper for us to make? Can item be purchased? Yes Yes Is the capital available? No No No Yes MAKE BUY BUY MAKE

Parts List A listing of component parts.

Bill of Materials Many different types of “structured parts lists”

Bill of Materials

Operation Description Route Sheet Company: ARC Inc. Produce: Air Flow Regulator Part: Plunger Housing Part No. 3254 Prepared by: JSU Part No. 6/6/03 Oper. No. Operation Description Machine Type Tooling Setup (hr.) Oper. Time (hr.) Mtls. Parts 0104 Shape, drill, cut off Auto sc. Machine .5 in dia coller, cir. Form tool, .45” diam center drill 5 0.0057 Alum 1”x12’ 0204 Machine Slot and thread Chucker 0.045” slot saw, turret slot 2.25 0.0067 0304 Drill 8 holes Auto dr. unit 0.078” diam twist drill 1.25 0.0038 0404 Debur and Blow out Drill press Deburring tool with pilot 0.5 0.0031 SA 1 Enclose subassembly Dennison hydraulic press None 0.25 0.0100

Routing sheet

Analog model of the assembly process. 2200 Assembly Chart 3254 Analog model of the assembly process. Circles denote components Links denote operations/subassemblies Squares represent inspections operation Begin with the original product and to trace the product disassembly back to its basic components. 3253 3252 3251 SA-1 A-1 3250 3255 A-2 4150 4250 A-3 I-1 1050 A-4 Pack

Assembly Charts ９ ５ ６ ７ ８ 1１ 1０ 1２ ３ 1 ４ ２

Operations Process Chart Found by superimposing the route sheets and the assembly chart, a chart results that gives an overview of the flow within the facility. Operations Process Chart

Volume Variety Charts

Volume Variety Chart

Production Requirements – Yield Loss Pi – Production input to operation i si – Fraction of Pi lost (scrap) Oi – output of process i Pi i Oi Pisi

Production Requirements – Series Systems 1 2 . . . P1 n On P1s1 P2s2 Pnsn

Example 5 processes in series Need 2000 units out

Production Requirements – Non Series Part A Part B Work backward from end of the line. M1 s1=1% 1 M2 s3=2% 3 M2 2 s2=2% M3 s4=1% 4 M4 s5=4% 5 100,000 units

Simple equipment selection model P desired prod rate t time (in hours) to process one part m/c avail time (in hours) m/c efficiency

Simple equipment selection model Nol Number of good units at output of stage l Nil Number of units reqd at input of stage l Sl Scrap at stage l

Simple example 1. Consider a simple job shop manufacturing system that makes three major “Class A” products requiring three types of machines. The three products include seven parts shown in Table 2.1. Table 2.1 also shows the time standards in units per hour. 2. Assume an hour has only 55 minutes of productive time and that 5 minutes are lost due to operator or machine unavailability and machine downtime. 3. Dividing the value 55 by the values in Table 2.1, we get the as well as time per unit. 4. Determine the quantities of machines of each type required to make the standard time per unit. 5. Assuming 12000 “representative” parts are to be made and that only 440 minutes of productive time is available per shift, we can find that we need 12000*0.1799/440= 4.9 units of machine A, 5.85 units of machine B, and 4.3 units of machine C. Rounding up these numbers gives us 5, 6, and 5 units of machine types A, B, and C, respectively.

Table 2.1

Table 2.2

Calculating Equipment Requirements How many pieces of equipment do we need? Pi Production rate for operation i (pcs/period) Ti Time per piece for operation i (time/pc) Ci Time available to run operation i (time/period) Ei Efficiency of machine while running Ri Reliability of machine Mj Number of type j machines required xj Set of operations run on machine j

Example Consider Machine 2 x2={2,3} Do similar calculation for other machines Other factors to consider Number of shifts Setup times Customer lot sizes (smaller require more setups) Layout type Maintenance activities

Operator-Machine Charts Tool for showing activity of both operator and machine along a time line Also called “multiple activity chart” Example: 1 minute to load 1 minute to unload 6 minute run cycle 0.5 minute to inspect and pack 0.5 minute to travel to another machine

Operator Machine Charts

Parameters for an LP equipment selection model Oi Operation type i, i=1,2,...,o Mi Production equipment type i, i=1,2,...,m Pi Part type i, i=1,2,...,p MHi Material handling system type i, i=1,2,...,n cij cost of performing operation Oi on production equipment type Mj hij cost of handling part type Pi using material handling system type MHj tij time required to perform operation Oi on production equipment type Mj sij time required to transport part type Pi using material handling carrier type MHj τj time available on production equipment type Mj σj time available on material handling carrier type MHj NOi number of operations Oi to be performed NPi number of units of part type Pi to be manufactured Cj cost of production equipment type Mj Hj cost of material handling system MHj B total budget available

Decision Variables for LP equipment selection model xij number of operations Oi to be performed on production equipment type Mj yij number of units of part type Pi to be transported on material handling system type MHj NMj number of units of production equipment type Mj selected NMHj number of units of material handling system type MHj selected MIDTERM,May3rd

LP equipment selection model Min Subject to

LP equipment selection model (cont)

Example An automobile engine cylinder manufacturing company that supplies high precision engines to a multinational car manufacturer plans to manufacture several models of cylinder. For planning purposes, it uses the following pseudo products - a standard(basic) engine cylinder, a high-technology model, an engine cylinder for sports cars and a luxury car cylinder. The marketing department has demand forecast figures which have been aggregated for the four pseudo models. It has been determined that 2000, 1500, 1800 and 1000 units of the basic, high-tech, sports and luxury models will be demanded during the next six months.

Example The models require one or more of three operations, referred to as O1, O2, and O3. Three machine types and two material handling systems available for performing the three operations and transporting the models. These are denoted as M1, M2, M3 and MH1, MH2, respectively. Each machine and handling system may be assumed to be available for 90 percent of the time. The cost of machines M1, M2, and M3 are $230,000; $250,000; $310,000. The number of operations needed of each machine is 200,200 and 150 respectively. The cost of material handling carriers MH1, MH2 are $90,000 and $130,000 The available budget is $10,000,000. The following two matrices show the cij's and hij's - that is, the cost of performing operation Oi on production equipment type Mj and cost of handling part type Pi using material handling system type MHj, respectively. (Units/ 10 unit time)

Data for example

LP Model for example MIN 90000 NMH1 + 130000 NMH2 + 230000 NM1 + 250000 NM2 + 310000 NM3 + 6 X11 + 12 X12 + 8 X13 + 4 X21 + 5 X22 + 4 X23 + 12 X31 + 5 X32 + 5 X33 + 10 Y11 + 5 Y12 + 12 Y21 + 6 Y22 + 18 Y31 + 9 Y32 + 6 Y41 + 3 Y42 SUBJECT TO C1) X11 + X12 + X13 >= 200 C2) X21 + X22 + X23 >= 200 C3) X31 + X32 + X33 >= 150 C4) - 300 NM1 + 1.67 X11 + 2.5 X21 + 0.83 X31 <= 0 C5) - 300 NM2 + 0.833 X12 + 2 X22 + 2 X32 <= 0 C6) - 300 NM3 + 1.25 X13 + 2.5 X23 + 2 X33 <= 0 C7) Y11 + Y12 >= 2000 C8) Y21 + Y22 >= 1500 C9) Y31 + Y32 >= 1800 C10) Y41 + Y42 >= 1000 C11) – 300 NMH1 + 0.1 Y11 + 0.0833 Y21 + 0.056 Y31 + 0.167 Y41 <= 0 C12) - 300 NMH2 + 0.2 Y12 + 0.167 Y22 + 0.11 Y32 + 0.33 Y42 <= 0 C13) 90000 NMH1 + 130000 NMH2 + 230000 NM1 + 250000 NM2 + 310000 NM3 <= 1000000 END GIN 5

LP Model Solution VARIABLE VALUE REDUCED COST NMH1 2.000000 90000.000000 NMH2 .000000 105454.546875 NM1 2.000000 228562.875000 NM2 1.000000 248353.593750 NM3 .000000 308353.593750 X11 200.000000 .000000 X12 .000000 2.571524 X13 .000000 .860030 X21 59.880245 .000000 X22 140.119751 .000000 X23 .000000 1.744012 X31 140.119751 .000000 X32 9.880246 .000000 X33 .000000 .000000 Y11 2000.000000 .000000 Y12 .000000 11.363637 Y21 1500.000000 .000000 Y22 .000000 7.663636 Y31 1800.000000 .000000 Y32 .000000 .000000 Y41 1000.000000 .000000 Y42 .000000 24.000002

Parameters for LP equipment selection model rik number of times operation Oi is to be performed on part type Pk cijk cost of performing operation Oi using production equipment type Mj on part type Pk tijk time required to perform operation Oi using production equipment type Mj on part type Pk xijk number of units of operation Oi performed using production equipment type Mj on part type Pk Cj purchase cost of production equipment type Mj prorated over the planning period

LP equipment selection model Min Subject to

Queuing Model Manufacturing engineers at the Widget Manufacturing Company recently convinced their manager to purchase a more expensive, but flexible machine that can do multiple operations simultaneously. The rate at which parts arrived at the machine that was replaced by the flexible machines follows a Poisson process with a mean of 10 parts per hour. The service rate of the flexible machine is 15 parts per hour compared with the 12 units per hour service rate of the machine it replaced. (All service times follow an exponential distribution.)

Queuing Model The engineers and manager were convinced that the company would have sufficient capacity to meet higher levels of demand, but just after a two months of purchasing the machines it turned out that the input queue to the flexible machine was excessively long and part flow times at this station were so long, that the flexible machine became a severe bottleneck. The engineers noticed that more parts were routed through this machine, and that the parts arrival rate to the flexible machines had increased from 10 per hour to about 14 per hour, but were puzzled why the part flow time at this station doubled from 30 minutes to one hour and the work-In-process (WIP) inventory increased nearly threefold from 5 to 14 when the arrival rate only increased 40%. Use a queuing model to justify the results observed at Widget Manufacturing Company.

M/M/1 Model Solution

Personnel requirements analysis n number of types of operations Oi aggregate number of operation type i required on all the pseudo (or real) products manufactured per day Ti standard time required for an average operation Oi H total production time available per day η assumed production efficiency of the plant

Queuing Model The American Automobile Drivers’ Association (AADA) is the only office serving customers in New York’s greater capital district area. Ahead of the busy summer season, the office manager wants to hire additional staff members to help provide these services to members effectively - summer travel planning, membership renewal, disbursing traveler’s checks, airline, hotel, and cruise booking, and other travel related services. It is anticipated that each customer typically requires 10 minutes of service time and customers arrive at the rate of one customer every three minutes. The arrival process is Poisson and the service times are exponentially distributed. Determine how many staff members are required if the average wages and benefits per staff member are $20 per hour and the “cost” to AADA for every hour that a customer waits to be served is $40.

M/M/m Model Solution

Production space requirement sheet