1. Product and Equipment Analysis
Chapter 2
S.S. Heragu, Facilities Design, 4th Edition, CRC Press

2. Data required for developing good layouts
Product Analysis
Process Analysis

3. 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?)

4. Product Analysis Bill of Materials Assembly Charts Engineering Drawing
Operation Process Chart
Route Sheet

5. 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

6. 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

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

8. Assembly Chart

9. Bill of Materials

10. Part Drawing

11. 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

12. 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

13. 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

14. 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

15. Parts List
A listing of component parts.

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

17. Operation Description
Route Sheet
Company: ARC Inc.
Produce: Air Flow Regulator
Part: Plunger Housing
Part No
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

18. Routing sheet

19. 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

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

21. Symbols for 5 basic mfg activities

22. Operation process chart for 3.5 volt halogen otoscope

23. 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

24. Volume Variety Charts

25. Volume Variety Chart

26. Equipment Selection
Traditional Model
Queuing Model

27. Equipment Selection

28. 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

29. Production Requirements – Series Systems1 2
. . . P1 n On
P1s1
P2s2
Pnsn

30. Example
5 processes in series
Need 2000 units out

31. 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

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

33. Traditional 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

34. Simple example
1. Consider a simple jobshop manufacturing system that makes three major “Class A” products requiring five 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 we 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 “representative” parts are to be made and that only 440 minutes of productive time is available per shift, we can find that we need 4.9 units of machine A, 5.85 units of machine B, and 4.3 units of machine C. 6. Rounding up these numbers gives us 5, 6, and 5 units of machine types A, B, and C, respectively.

35. Table 2.1

36. Table 2.2

37. 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

38. 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

39. 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

40. Operator Machine Charts

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

42. 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-n-process (WIP) inventory increased nearly threefold from 5 o 14 when the arrival rte only increased 40%. Use a queuing model to justify the results observed at Widget Manufacturing Company.

43. M/M/1 Model Solution

44. 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

45. 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.

46. M/M/m Model Solution

47. Production space requirement sheet
Departmen t Name
Work Center Name
Work Center Code
Length (feet)
Width (feet)
Area (feet2)
Auxiliary Area (feet2)
Operato r Space (feet2)
Material Space (feet2)
Sub- Total (feet2)
Allowance (feet2)
Total space per machine (feet2)
Number of Machines
Total Space Machine Type (feet2)
General Machining
Vertical Milling
1202 15
225 70 30 50
375
150%
565 2
1130
Planer
2005L 25 5
125 40 20
125%
290 1
Punch Press
3058 10
100
170
140%
240
480
Injection Molding
6078
200 60
410
615 3
1845
Otoscope Cell
NC-Machine
9087 8
160
270
340
680
Lathe
1212
120
210
315
Auto- Chucker
2056 45