1 Process Mapping BA 339 Mellie Pullman. 2 Objectives Service Process Differences Little’s Law...

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1

Process Mapping

BA 339

Mellie Pullman

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Objectives

Service Process Differences Little’s Law Process Analysis & Mapping

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Measuring Process Flows

Capacity of a system = capacity of the most constraining resource.• We also called it a ‘bottleneck.’

The flow rate of a process is the minimum of:• Supply rate

• Demand rate

• Capacity rate

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Example: Bank Clearing House

What is the capacity of the system to process checks?

Receive Checks1000 checks/hour

Sort Checks by Bank

800 checks/hour

Ship Checks1200 checks/hour

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Measuring Process Flows

Little’s Law• Relates number of items in the system to arrival

rate and length of time in the system.

• Formula:I = T x R

I = average number in the systemT = average throughput timeR = average flow rate into the process

Assumes system is in a ‘steady state’

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Example: Bank Clearing House

If the rate of checks into the system is 600 checks per hour (supply), what is the flow rate?

There is an average of 200 checks in the system, what is the throughput time of checks?

How can we reduce the throughput time of checks?

Receive Checks1000 checks/hour

Sort Checks by Bank

800 checks/hour

Ship Checks1200 checks/hour

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Applications of Little’s Law

Manufacturing Waiting lines Invoice processing Legal office transactions Accounts receivable

processing Restaurant & Theme

Park Design Many others!!!!

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Sell-by-Dating for Fresh Beverages

Your store sells 20 bottles of “Fresh Local Beverage” per day,

The producer says that product has a shelf life of 30 days (your warehouse & store),

What is the maximum inventory that you should hold to insure fresh beverages?

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Process Flow Mapping & Analysis

Purpose: to describe a process visually to

find ways of improving the current process.

• Find repetitive operations

• Identify bottlenecks

• Describe directions and distances of flows (people,

material and information)

• Create better value & reduce waste

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Detailed Process MapIdentifies the specific activities that make up

the process. Basic steps are:

Identify the entity that will serve as your focal point: Customer? Order or item?

Identify clear boundaries, starting and ending points, and line of visibility between customer and order.

Keep it simple Does this detail add any insight? Do we need to map every exception condition?

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Classifying Processes

Process

Operations Transportation

Delays

Inspections

Storage

Input Output

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Mapping Symbols

Operation (task or work activity)

Inspection

Decision point (typically requires a “yes” or “no”)

Document or order created

Delay

Storage

Move Materials or employees activity

or

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Distinguish between Value-Add and Non Value-Add Process Step

Value Add (VA) Business Non-value-add (BNVA) Non-value-add (NVA)

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Value Add Steps Work that contributes what your customers

want out of your product or service• Cooking a meal• Measuring & Cutting Material• Assembling

Does it meet these criteria?• Adds a desired function, form, or feature to

the product or service• Enables a competitive advantage (reduced

price, faster delivery, fewer defects)• Includes an activity that a customer would

be willing to pay for or would not prefer our competitors is he/she knew we did this task.

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Business Non-Value Add

Activities that your customer doesn’t want to pay for (it does not increase value in their eyes) but are required for some reason

• Accounting, legal, regulatory Is task required by law or

regulation? Does task reduce financial/liability

risk? Does task support financial

requirements? Does process break down if task is

removed?

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Non-value Add

Work that does not add value in the eyes of the customer and that they would not want to pay for it (nor is it required for BNVA)• Rework, multiple signatures & copies,

counting, handling, inspecting, set-up, downtime, transporting, moving, delaying, storage.

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Process Chart (supplements Map)

Measure

A

Measure

B

Activity

(O, I, S, D, TP, TI)

Value Code

(V/B/N)

Description of activity

O= operations; I= inspections; S= storage; D=delay; TP= transportation of peopleTI= transportation of inventory or materials

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Linking Processes to Value with Metrics

Possible Measures or Metrics:• Link desired customer value to process

• Time (measure distance traveled and task time)

• Cost

• Quality

• Flexibility

• Sustainability

• Set standards

• Guide design of new or redesign of existing process

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Including Time & Quality Measures

DealerFaxesOrder

PaperOrder

Created

Order SitsIn FaxIn Box

Internal MailDelivers Fax

Order SitsIn Clerk’s

In Box

ClerkProcesses

Order

Is ItemIn Stock?

WorkerPicksOrder

Clerk NotifiesDealer and

Passes OrderOn to Plant

InspectorChecksOrder

Transport FirmDelivers Order

DealerReceives

Order

2 minutes0.5% of orders incorrect1 to 3 hours

2 hours on averageNo history of lost,damaged, or incorrectdeliveries

YES

NO

10 to 45 minutes20 minutes on average

0 to 2 hours1 hour on average0.5 to 1.5 hours

1 hour on average1% of orders lost

0 to 4 hours2 hours on average

4% oforders lost

5 minutes

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Process Flow Analysis Might Change:

Raw materials Product (output) design Job design Processing steps used Management control information Equipment or tools Suppliers i.e. Anything but customers may be changed!!

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Steps in process flow analysisusing the systems approach

Select a process to study

Find a group of “different eyes” to analyze & improve the

system

Decide on the objectives of the analysis

improve cost, quality, flexibility, responsiveness (service),

sustainability (ergonomics, recycling, reduce energy)

Define customers and suppliers

Flowchart the existing transformation process

Develop improved process design

Implement the new process design

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Questions to ask to improve process flow

What does the customer need?, operations are necessary? Can some operations be eliminated, combined, or simplified?….

Who is performing the job? Can the operation be redesigned to use less skill or less labor? Can operations be combined to enrich jobs? ….

Where is each operation conducted? Can layout be improved? ….

When is each operation performed? Is there excessive delay or storage? Are some operations creating bottlenecks? …..

How is the operation done? Can better methods, procedures, or equipment be used? ….

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In Class Exercise:Process Flow Diagrams & Value-adding activities

Do a process flow diagram and process chart for Pizza Delivery (show operator & customer perspectives)

Evaluate value-adding and non-value adding activities (V,B,N). Justify your decision.

How would you modify or delete

non-value added activities?