Product Process

& Schedule Design

Relationship between product, process, and schedule design and facilities planning

Facilities

planner

Product designers

Process planner

Production Planner

Before any facility plan can be generated, the

following questions should be addressed

1. What is to be produced?

2. How are the products to be produced?

3. When are the products to be produced?

4. How much of each product will be produced?

5. For how long will the products be produced?

6. Where are the products to be produced?

Relationship between product, process,

and schedule design and facilities planning

Product design

Process design

Facilities design

schedule design

Figure 2.1

Relationship between product, process , and schedule (PP&S) design facilities planning.

Facility planning functions relationship

Links between components:

Product

Change in the design of a product.

Introducing a new product.

A significant increase in demand.

________________________________

Process:

Chang in the design of a process.

Replacement of a machine.

Adaptation of new standards.

Facility planning functions relationship

Links between components:

Scheduling:

Bottlenecks

Delay and idle time.

Excessive temporary storage

Obstacles to material flow.

High ratio of material handling time/production time

Product, Process & Scheduling Design Interaction

•Product Design 1

•Process Design 2

Product, Process & Scheduling Design Interaction

•Scheduling Design 3

•Facilities Design 4

Customer Needs

• Market Surveys, Benchmarking

• QFD, HOQ …. etc.

Product Designer

• Exploded Assembly Drawing or Photograph

• Can be prepared and analyzed by CAD

Component Design

• Detailed component part drawing

• Can be prepared and analyzed by CAD

1. Product Design Steps

Product Design

Product design involves

The determination of which products are to be produced

The detailed design of individual products.

Decisions regarding the products to be produced are

generally made by top management based on input from

marketing, manufacturing, and finance concerning projected

economic performance.

Product Design

Product must meet customer needs, this challenge can be

achieved by designers using QFD and benchmarking.

Either Exploded Assembly Drawing or Photograph can be

used to show the parts properly oriented.

Detailed component part drawing are needed for each

component part.

Drawings can be prepared and analyzed by CAD system.

Product Design involves:

Quality Function Deployment (QFD)

House of quality (HOQ)

Benchmarking

Design for Manufacturing and Assembly (DFMA)

Prototyping (The first testing pattern)

Exploded Assembly Drawing

Photography

CAD drawing

Figure 2.2 Exploded assembly drawing

Exploded Assembly Drawing

materials in

an airplane

Exploded Assembly Drawing

Figure 2.3 Exploded Assembly Photography

Figure 2.4 Component part drawing of a plunger

Identifying Required Processes

• Make or Buy Decision & Parts list.

• Bill of Materials (BOM) & Product Structure.

Selecting Required Processes

• Route sheet.

Sequencing Required Processes

• Assembly Chart, Operation Process chart & Precedence Diagram.

2. Process Design Steps

Process Design

How the product is going to be produced, on which machine, make or buy

decision, how long it will take to perform the operation.

Basically process design consists of 3 stages:

1. Identifying the required process

make-or-buy decision

part list

bill of materials

Process Design

2. selecting the required processes

process selection procedure

route sheet

3. sequencing the required processes

assembly chart

operation process chart

Precedence diagram

Process selection

& Design process

Make or Buy

Decision Process

Figure 3.6

The make-or-buy

decision process.

Process Identification

Define elemental operations Step 1

Identify alternative processes for each operation Step 2

Analyze alternative processes Step 3

Standardize processes Step 4

Evaluate alternative processes Step 5

Select processes Step 6

Computer Aided Process Planning (CAPP) - Variant

-Generative

Figure 3.10 Process selection procedure

After Make or Buy decision

After the make or buy decisions have been made, a list of items to be

made and the items to be purchased will be determined.

The listing often takes the form of a parts’ list or a bill of materials. A parts

list includes at least the following

1. Part numbers

2. Part name

3. Number of parts per product

4. Drawing

Process Design

A part list

1) part number

2) part name

3) number of parts

4) drawing number

5) material

6) size

7) quantity

8) make or buy

Figure 3.8 Bill of martials for an air flow regulator

Level I: subassemblies and components that feed directly into level

Figure 3.9 Bill of materials for an air flow regulator

Selecting the Required Processes

After determining “in house” parts, decisions are needed as to how the

products will be made:

- previous experiences

- related requirements

- available equipment

- production rates

- future expectations.

Outputs are processes, equipment, and raw materials required for the in-

house production of products, also called a route sheet.

Route sheet

The outputs from the process selection procedure are the processes,

equipment, and raw materials required for in-house production of

products. Output is generally given in the form of a rout sheet.

It lists, in addition to part information, the related operations for each

make component.

Figure 3.11 Route sheet for one component of the air flow regulator

Sequencing the Required Process

The method of assembling a product is accomplished by the

assembly chart.

Assembly chart – shows the sequence of operations in

putting the product together.

The easiest method of constructing an assembly chart is to

begin with the completed product and trace the product

disassembly back to its basic components.

Assembly Chart ”The easiest way of

constructing an

assembly chart is to

begin with the

completed product

and to trace the

product disassembly

back to its basic

components”

How to construct it?

Figure 3.12 Assembly chart for an air flow regulator

Sequencing the Required Process

Although route sheets provide information on

production methods and assembly charts indicate

how components are combined, neither provides an

overall understanding of the flow within the facility.

This is accomplished with the operation process

chart.

To provide an overview of

the flow within the facility

we impose the rout sheet

on the assembly chart. The

resulting chart is referred to

as an operation process

chart.

How to construct it?

Operation process chart

analog model of overall

production process

Sequencing the Required Process

A second viewpoint (from graph and network theory) is to

interpret the charts as network representations, or more

accurately, tree representations of a production process.

A variation of the network viewpoint is to treat the assembly

chart and the operations process chart as special cases of a

more general graphical model, the precedence diagram.

Precedence

diagram

A network representation of all

processes need to executed

successively. “ The diagram can be of

significant benefit to the facilities

planner. It establishes the

precedence relationships that must

be maintained in manufacturing and

assembling a product”.

Figure 3.14 Precedence diagram for an air flow regulator

Marketing Information

• Quantitative Information such as volume, trend, and predictability of future demand for various products

• Qualitative information

Process Requirements

• Calculation of production requirements

• Calculations with rework

• Reject allowance problem

• Estimation the number of machines required

3. Scheduling Design Steps

As a minimum, the market

information needed for

facilities planning is given

in the table.

Marketing

Information -

Quantitative

Ideally, information of the

type shown in this table

would be provided. If such

information is available, a

facilities plan can be

developed for each

demand state, and a

facility designed with

sufficient flexibility to meet

the yearly fluctuations in

product mix.

Marketing

Information -

Quantitative

The qualitative information

listed in this table shall be

obtained as well. This

information may provide

valuable insight to facilities

planner.

Marketing

Information -

Qualitative

The figure above suggests

that the facilities plan

should consist of a mass

production area for the

15% of high volume items

and a job shop

arrangement for the

remaining 85% of the

product mix.

Pareto law dose not apply

for the figure below.

Marketing Information

– Pareto’s Diagram

Example 2.1:

A product has a market

estimate of 97,000

components and requires

three processing steps

(turning, milling, and

drilling) having scrap

estimates of P1 = 0.04, P2

= 0.01, and P3 = 0.03

Process Requirements

105,219 101,010 100,000

0.04 0.01 0.03

97000

Example 2.2:

The end product

requirement is 100,000

pieces, Assume that the

defective rate in (decimal)

are d1= 0.03, d2 = 0.40,

and d3 = 0.02

Solution:

Applying this equation, The

initial input required is

103,280

Process Requirements

QC

Tools

• Some quality Tools such as Pareto Chart can be used

Deming

Wheel

• Deming BDCA Cycle of continuous improvement can be very useful (Plan-Do-Check-Act)

Seven Management

& Planning Tools

• Affinity diagram, Interrelation Diagraph, Tree Diagram, Matrix Diagram, Contingency Diagram, Activity Network Diagram, and Prioritization Matrix.

4. Facilities Design Steps

7 management and planning tools

The seven management and planning tools are

1. The affinity diagram,

2. The interrelationship digraph,

3. The tree diagram,

4. The matrix diagram,

5. The contingency diagram,

6. The activity network diagram, and

7. The prioritization matrix.

The affinity diagram is used to gather verbal data, such as ideas and issues, and organize it into groupings. Suppose we are interested in generating ideas for reducing manufacturing lead time. In a brainstorming session, the issues are written down on "post-it“ notes and grouped on a board or wall. Each group then receives a heading. An affinity diagram for reducing manufacturing lead time is presented in the following figure.

Affinity Diagram

Procedure:

1. State the issue in a full sentence.

2. Brainstorm using short sentences on

self-adhesive notes.

3. Post them for the team to see.

4. Sort ideas into logical groups.

5. Create concise descriptive headings for each group.

Affinity Diagram

Affinity diagram example

for reducing

manufacturing lead

time

Affinity Diagram

The interrelationship

digraph is used to map

the logical links among

related items, trying to

identify which items

impact others the most.

The term digraph is

employed because the

graph uses directed

arcs

Interrelation

Diagraph

Suppose we want to

study the relationship

between the items in

previous figure under

facilities design. The

interrelationships are

presented in this figure.

Note that this graph helps

us understand the logical

sequence of steps for the

facilities design

Interrelation

Diagraph

Maps out the paths and tasks necessary to complete a specific project or reach a specified goal.

Benefits:

Encourages team members to think creatively.

Makes large projects manageable.

Generates a problem-solving atmosphere.

Tree Diagram

Procedure:

1. Choose an action-oriented objective statement from the interrelationship diagram, affinity diagram, brainstorming, team mission statement.

2. Using brainstorming, choose the major headings.

3. Generate the next level by analyzing the major headings. Repeat this question at each level.

Tree Diagram

Tree diagram for the

formation of product

families

Tree Diagram

The matrix diagram

organizes

information such as

characteristics,

functions, and tasks

into sets of items to

be compared.

Matrix Diagram

The contingency diagram, formally

known as process decision program

chart, maps conceivable events and

contingencies that might occur

during implementation.It is

particularly useful when the project

being planned consists of unfamiliar

tasks. The benefit of preventing or

responding effectively to

contingencies makes it worth while

to look at these possibilities during

the planning phase.

This figure shows an example of

possible contingencies during an

earthquake.

Contingency

Diagram

The activity network diagram is used

to develop a work schedule for the

facilities design effort. This diagram is

synonymous to the critical path

method (CPM) graph. It can also be

replaced by a Gantt chart and if a

range is defined for the duration of

each activity, the Program

Evaluation and Review Technique

(PERT) chart can also be used. An

example of an activity network

diagram for a production line

expansion is illustrated in this figure

Activity Network

Diagram

The important message is that a

well thought out time table is

needed to understand the

length of the facilities design

project. This timetable can be

developed after the actions on

the tree diagram have been

evaluated with the prioritization

matrix.

Teams activities can also be

planned as shown in this typical

weekly work schedule.

Activity Network

Diagram

In developing facilities design

alternatives it is important to consider:

Layout characteristics

Material handling

requirements

Unit load implied

Storage strategies

Overall building impact

The figure shows prioritization

matrix for the Evaluation of Facilities Design alternatives.

Prioritization Matrix

The prioritization matrix can be

used to judge the relative

importance of each criterion as

compared to each other. Table

2.12 presents the prioritization of

the criteria for the facilities

design example. The criteria are

labeled to help in building a

table with weights.

This figure shows the

Prioritization Matrix for Layout

Alternatives Based on WIP

Levels

Prioritization Matrix

Logical application

sequence of the seven

management and

planning tools is shown

in this figure.

Summary

This figure shows how

the seven

management and

planning tools

facilitate the planning

of a facilities design

project

Summary