LEAN MANUFACTURING PRINCIPLES AND THEIR APPLICATION 2008

Lean manufacturing, sản xuất

Trang 1

LEAN MANUFACTURING PRINCIPLES AND THEIR APPLICATION

Mehmet C Kocakiilah; Jason F Brown; Joshua W Thomson

Cost Management; May/Jun 2008; 22, 3; ABI/INFORM Global

pg 16

F—

LEAN MANUFACTURING

PRINCIPLES This articts presenta a brief history of lean manufacturing and then discusses the

different facets or tools that are components of an effective lean culture and program

AND THEIR APPLICATION

MEHMET C KOCAKULAH, JASON F BROWN, AND JOSHUA W THOMSON

ufacturing program are value focused on supplying exactly what the cus- stream mapping, 55, total pro- tomer wants,in the form they want it in,

single minute exchange of they want it, with minimal waste in the

dies (SMED) and Six Sigma There are also

lesser-used tools, or subsets of the major

tools, such as a Kaizen improvement culture, Hoshin Planning, mistake proofing, Jidoka, standardized work, and

process The following principles are

identified by the Lean Enterprise Insti-

tute as characteristics that identify a lean business:'

1 Specify value from the standpoint of just-in-time inventories Each of these tools

focuses on certain aspects and areas of 2

the manufacturing process in order to

help improve costs and efficiencies in a

company

Before looking at the historical origins

answer the important question: What is

lean? Stated in the most basic form, lean manufacturing and a lean enterprise or

the end customer by product family

Identify all of the steps in the value stream for each product family,

eliminating every step, every action,

and every practice that does not create value

Make the remaining value-creating

steps occur in a tight and integrated sequence so the product will flow

smoothly toward the customer

MEHMET C, KOCAKOLAH, Ph.D is professor of accounting at the University of Southern Indiana, Evansville, Indiana He can be reached by e-mail at mkocakul@usi.edu

JASON F BROWN is currently working as a Plant Engineering and Maintenance Manager in the plastics packag-

ing industry He received a Bachelor's degree in Mechanical Engineering from Rose-Hulman Institute of Technot- ogy in i993 and a Master’s degree in Business Administration from the University of Southern Indiana in 2008

JOSHUA W THOMSON is working as an Environmental, Health, and Safety professional, sharing responsibilities asa Continuous Improvement coordinater for Lean Enterprise Josh's degree in Mechanical Engineering from Ten- nessee Tech provides a structured and expansive skill set as @ champion for continuous change

COST MANAGEMENT MAY/JUNE 2008

16

Reproduced with permission of the copyright owner Further reproduction prohibited without permission

Trang 2

4 As flow is introduced, let customers

pull value from the next upstream

activity

5 As these steps lead to greater trans-

parency enabling managers and

teams to eliminate further waste,

managers pursue perfection through continuous improvement

A top-to-bottom lean enterprise works towards these characteristics by being

comprised of five elements:?

« A product development process

- A supplier management process

- A customer management process

- An overarching enterprise manage-

ment process

- A production process from order to

fulfillment

Each of these lean processes has been proven superior to processes employed

for the same tasks in a mass production

type of environment

The objective of this article is to pre- sent a brief history of lean manufactur-

ing and then discuss the different facets

or tools that are components of an effec-

tive lean culture and programs This dis-

cussion examines the specific impact of

each of the lean manufacturing tools on

the bottom line and performance of a

company

Lean manufacturing

The origins of lean date back to Henry Ford

and his first production line in Highland

Park, Michigan in 1913.* Ford was the first

person to consider the flow of produc-

tion His assembly line created the flow

or sequence in which interchangeable

parts were assembled with standardized

work to create Model Ts In terms of cur-

rent lean thinking, Ford’s first assembly

line is generally used as an example of

mass production that goes contrary to

many lean principles The inconsisten-

cies with lean are not about flow or inven-

tories (he was able to turn entire inventories

every few days) The problem was his abil-

ity to make only one variety of cars

As consumers began to demand more

variety, Ford and other producers began

adding larger and faster machines to

reduce process time but at the same time

adding complex routings, process step sep-

LEAN MANUFACTURING

aration, and inventory points Today’s computerized materials requirements planning (MRP) systems are evidence of :

this increased complexity through time

In 1902, slightly before Ford’s assem-

bly line, Sakichi Toyoda, the founder of :

the Toyota Group, invented a loom that would automatically stop if any threads

snapped.‘ This was an important inno-

vation and even today an important :

aspect of lean This invention reduced

scrap, raised yield, and allowed for multiple automated looms to be run by one

operator This process of stopping production to prevent defects is called Jidoka :

and is used in Toyota facilities today

In the 1930s and especially immedi-

ately after World War II, the Toyoda fam-

ily became fascinated with the Ford

automobile production line and decided :

to go into automobile production them-

selves.® In doing so, Kiichiro Toyoda, Taiichi Ohno, Shigeo Shingo, and others

thought that some simple innovations could make it possible to maintain a ; process flow and make operations flex-

ible enough to offer some variety in product offerings.® The innovations resulted

in an assembly line where parts and sup-

plies were only produced or purchased and brought to the line in the quantities

needed exactly when they were needed

The purpose was to match production requirements as closely as possible to customer demand Out of these innovations single minute exchange of dies (SMED) and just-in-time inventories were created This was the birth of the

Toyota Production System

The Toyota Production System is the starting point and basis for much of : today’s lean teachings and practice Toy- ota is considered the leading lean example worldwide It has become the world’s most profitable automaker and will soon

be its biggest As of March 2007, they :

had a fifteen percent market share in the United States, are poised to pass Ford :

this year, and will most likely pass GM

as well.’ This is all a strong indication that lean principles work in application

There has been so much focus on lean

manufacturing in recent years that some

additional facets, tools, or methodologies

have been pulled under the lean umbrella

MAY/JUNE 2008 COST MANAGEMENT

THE TOYOTA PRODUCTION SYSTEM IS THE STARTING POINT : AND BASIS FOR MUCH OF TODAY'S LEAN TEACHINGS AND PRACTICE

17

Trang 3

VSM IS THE BASIS FOR

PRIORITIZING LEAN

ACTIONS

18

—

with the Toyota Production System based

on how each company takes the lessons

and applies them One example is Six

Sigma It was pioneered by Motorola

in the 1980s and General Electric was one of the first companies to begin

to blend and combine the two method-

ologies.°

Regardless of the name or the origins

of the methodology, lean enterprise is all about serving the customer more efficiently and effectively Impacts on the bottom line are in elimination of wastes and

growth of customer base

Value stream mapping

Value stream mapping (VSM) isa visual

way of representing the flow of infor-

mation and materials in the production

of products This creates a simple way for

managers to see flow of value Value is

being defined as those things done to transform a product into the form the customer wants and for which the customer

is willing to pay

Value stream mapping helps manage-

ment to visualize information and product flow, waste, the relationship between

information and material flow VSM is the basis for prioritizing lean actions It helps managers identify the classic seven

wastes in processes in lean manufactur-

ing principles:

1 Over production-Producing more than what is needed for the customer or the next process step

2 Transportation-Moving product between process steps, from production to the warehouse, from the warehouse to shipping, or any other

form of movement that is not part

of product transformation

3 Inventory-Includes both work in

process inventories and finish goods inventories,

4 Motion-Unnecessary motion ina process For example, poor work

station design causing an employee

to reach for needed items resulting

in time losses or wasted motion in

the pattern of a robot

5 Waiting-Machines or process steps waiting for work-in-process or component parts to arrive

6 Defects~Any undesired characteris-

tic that affects product fit, form,

function, or appearance

7 Over processing-An example would

be slowing down a machining operation to obtain a finer surface finish than required

These wastes are readily apparent in every manufacturing facility in the world,

even in Toyota manufacturing facilities

Some of them are unavoidable It is those

companies who identify, manage, and

minimize these wastes that are able to succeed the best in this very competitive

marketplace

The first step in creating a value stream map is to group and identify product

families These are groups of products,

which proceed through the same basic steps and equipment within the company Sec- ondly, the flow of information to and

from the customer to the company and

to and from the company to suppliers is

mapped from right to left across the top

of a sheet, board, or easel This should include a calculation of takt time Takt time is defined as the effective working time per shift divided by the customer

requirements per shift The calculation

of takt times gives manager their goal or

target in order to synchronize the pace

of production to match the pace of sales

The next step is to walk the process and

document inventory levels and process cycle times along with changeover times

These are documented from left to right

across the bottom of the sheet It is important to use actual inventory levels and times

as they are recorded on the floor, not

standards The flow of information from

support areas to production is added and determinations are made as to what process steps are truly value added The final step is the calculation of lead times and what ratios of the lead time are value

added and nonvalue added activities

The map that results from these steps

is called a current state map utilized to

focus improvement efforts All of the nonvalue added times are wastes and are

potential areas for improvement As opportunities for improvement are identified, a new map can be created show- ing all potential improvements It is referred to as a future state map and iden-

LEAN MANUFACTURING

Trang 4

tifies the target for the process to look

like in the future

VSM in itself does not have a direct

effect on the bottom line of a company,

but it is a method of visually represent-

ing where wastes occur in manufactur-

ing or service processes The map points

to the places where the utilization of

lean tools can directly affect the bottom

line by eliminating waste

5S

While value stream mapping is consid-

ered by many to be the basic tool for

management to start towards a lean oper-

ation, a 5S methodology is absolutely

necessary on the plant floor as a foun-

dation for later improvements 5S was

originally started by Toyota to describe

the proper methods of housekeeping

The 5Ss refer to the words used to describe

the steps in each process in both Japan-

ese and their English translations:

> Seiri Separate

+ Seiketsu Standardize

-Ổ Shitsuke Sustain

Some lean companies refer to their 65

program, adding safety into the mix

55 is usually performed in what are called Kaizen events These events include

a cross section of management and pro-

duction people who are taken from their

daily routines and asked to focus on a lim-

ited specific area The first step, separate,

is an evaluation and removal of anything

that is not needed for the tasks performed

in any given area Some companies use

a “red tag” process for these unneeded

items The items are identified with a

red tag giving the information as to what

it is and from where it was taken The items

are then placed in a designated area for

one week This week allows all in the

plant to review the item and to insure that

the team did not remove something that

was actually needed

The next step, sort, involves defining

a specific place or area for the remain-

ing items that are required to perform the

task in the area They are located in an

optimum fashion for ergonomics and to

minimize motion, one of the seven wastes

LEAN MANUFACTURING

mentioned earlier The locations are labeled and marked with visual aids so

that missing items can be easily identi-

fied This can include tape around locations on the floor, labels on drawers or bins, or things such as shadow boards for tools

The third step in the 5S methodology,

sweep, is self-explanatory Everything must be kept clean and free of debris In

a lean company with a good 5S program the equipment is painted in light colors

This helps to show the dirt and oil because

these things can be symptoms of the

machine not performing correctly

The fourth step, standardize, means keeping things consistent from area to area Multiple workstations for the same

process are all to be set up identically

This leads to standardized work, every-

one performing tasks the same way, and also supports flexibility for employees

across workstations The final step, sus-

tain, is maintaining the discipline to keep the area clean and in order day in

and day out This is more a cultural

change than anything else

The greatest benefit from a 5S pro-

gram is discipline, but there are others

as well Standardization of work areas

and documentation can lead to reduced cycle times, greater cost efficiency, and

reduced motion, which directly affect the wastes of transportation and inventory An ideal plant layout is raw mate-

rial in one side and finished goods out the other with one piece pull flow through

the plant in between Disconnected processes tend to have more inventories

building up between them

5S is the first lean perspective on flow and layout This affects the bottom line through greater efficiency Eliminating wasted movement means the same amount

of work can be done with a smaller more

efficient work force Less money is tied

up in inventories Fewer defects are produced because everyone performs activities in the same way

Total productive maintenance

As a company begins working towards

a lean enterprise and synchronous flow

of batches of parts across machines,

ASS METHODOLOGY

IS ABSOLUTELY NECESSARY ON THE PLANT FLOOR AS A FOUNDATION FOR LATER

IMPROVEMENTS

19

Trang 5

FY

(Exhibit 1 OEE-A Key Metric

OEE = Availability x Performance Efficiency x Rate of Quality Products

(Total Available Time — Downtime)

(Total Available Time) x 100

° Performance Efficiency _ (Ideal Cycle Time x Processed Amount) = x

(Operating Time) (Processed Amount — Defect Amount)

100

¢ Rate of Quality Products =

—

:_ machine availability, and uptime becomes : a major issue It is estimated that the : cost of unscheduled equipment down-

: time in lean manufacturing environ- : ments without excessive inventory buffers

: is five to thirty times what it is in other

: manufacturing environments.’ It results : directly and immediately in lost oppor-

: tunity, failed shipping schedules, and : lost sales Total productive maintenance,

: or TPM, is the methodology used to

: attack issues with machine uptime The : main metric of a TPM program is over- : all equipment effectiveness (OEE) as : illustrated in Exhibit 1

: Availability measures if the machine

is down and cannot run Performance : measures if the machine is running at : its optimal speed Rate of quality mea-

> sures how many defective parts a machine : produces World-class OEE is generally : considered to be eighty-five percent

: Six factors cause OEE numbers to drop:

1) machine breakdown; 2) machine set- :_ up; 3) slowdown or stoppage of machine;

- 4) slow cycle time; 5) start-ups; 6) defects

- and rework These losses are the focus : of what TPM is used to minimize OEE

: and evaluation of these six losses are

: calculated and compiled in the first phase

: of TPM, the measurement cycle

: The second phase, the condition cycle,

: involves evaluation of data and formu-

- lation of an improvement plan for the

- machine (as well as an initial cleanup of

a,

(Processed Amount)

x 100

cai

the machine) The cleanup of the machine and the discipline to keep it clean is very important based on the 5S principles

Dirt, excess grease, and grime cover up

and hide important signs that can indi-

cate issues with equipment

The third phase of TPM is the problem prevention cycle In this phase

employees complete the planned improvements and then take TPM a step further by developing best practice routines and standards, which they then apply to all similar machines in operation This helps to insure that things are being performed in the same manner

on all machines The goals of TPM efforts

are shown in Exhibit 2

Once the problem prevention cycle is reached, continuous ongoing monitor-

ing and improvement are an important part of TPM This is also the point at

which a good predictive maintenance program also aids in detecting issues so that they can be addressed before they become unscheduled downtime Ongo-

ing monitoring of measures such as “mean time to repair, “costs of maintenance,”

“cost and rationalization of spare parts,”

“compliance to preventive maintenance schedules,” and “mean time between fail- ures” all feed into reduced machine problems and greater OEE numbers

Another aspect of TPM is called autonomous maintenance This is where responsibility for many of the basic

LEAN MANUFACTURING

Trang 6

Exhibit2 What We Want to Achieve >)

Reliability Does not need constant * Low failure rate

adjustment or attention for ¢ Low rate of minor stops minor stoppages + Low quality defect rate

* Needs little adjustment

* Reliable control system General Deterioration is easily measured | * Mechanical or electrical failure is easily detected and Maintainability and corrected located

Parts are easily replaced

* Easy to inspect

* Readily accessible for maintenance Operator Operators can easily perform ¢ Easy to clean

Maintainability maintenance tasks such as ° Easy to carry out checks on

oe lubricating, and * Waste is easy to collect ening * Inspection of machine operation is easily carried out Operability Can be set up and operated * Easy to set up and adjust

easily + Easy to use with simple contro! buttons

* All measurement indicators are accessible and easily read

Safety and Does not constitute a risk to * All moving parts are securely guarded Environment health or safety + Dust/Vapor extraction is more than adequate

* No unnecessary projections or sharp corners

equipment maintenance functions is

transferred from maintenance mechan-

ics or technicians to the operators who

run the machines on a day-to-day basis

These operators are the people who are

most familiar with the equipment and

how it runs They are best positioned

to detect abnormalities, correct small

ones, continue operation, and set and

maintain optimal conditions The goal

is not to eliminate the need for main-

tenance personnel, but to have people

most intimately familiar with the equip-

ment to be the first line of defense

against problems

The entire focus of a TPM program is

to keep equipment effectiveness on lev-

els that allow for smooth flow with min-

imal inventories through production

Waiting or downtime on machines is

much more costly ina lean environment

TPM rolls predictive maintenance, pre-

ventive maintenance, and autonomous

maintenance (operators being responsible

for basic maintenance activities on their

machines) into one program focusing

on having no unplanned downtime This

creates well-defined capacity numbers for

planners and schedulers Machine reli-

LEAN MANUFACTURING

ability allows management to remain aware of capacity levels and more accu- rately plan and react to variations in sales Improved impacts on the bottom line come from on-time deliveries to

customers, reduced inventory costs, and

lower scrap numbers

Single minute exchange of dies

Single minute exchange of dies (SMED) was developed by Shigeo Shingo in 1950s Japan in response to the emerging needs

of increasingly smaller production lot sizes required to meet the needed flex-

ibility for customer demand It was originally developed through the study of a die change process The die changeover was monitored and evaluated to deter- mine what could be done to increase the

speed and accuracy of the changeover

SMED more generally seeks to stan-

dardize and simplify so that the need for

specially skilled workers is minimized

SMED has now been expanded to vir- tually any changeover of equipment

The definition of a changeover on a process is the amount of time from the

last good piece of production of item A,

MAY/JUNE 2008 COST MANAGEMENT 21

Trang 7

( Exhibit 3 Shingo’s Three-Stage Concept

Convert internal steps into external and

Stage 3:

Shorten the internal steps Improve the external steps Standardize the new changeover procedure

Ko

to the first good piece of production of

item B Today’s SMED practices target

changeovers of ten minutes or less Some

companies that have fully embraced lean

teachings are targeting “zero changeover,”

which is considered three minutes or

less As suggested in the TPM section, if

a machine is not producing product dur-

ing changeover it affects the flow of prod-

uct through the plant As a company

becomes more sensitive to customers’

needs and more flexible, the need for an

effective SMED program increases due

to smaller and smaller production lot

sizes VSM helps to point the way to areas

in the plant where SMED needs to be

applied for increased overall throughput

Shingo’s plan for improvement involved

three stages, illustrated in Exhibit 3

It is important to define the differ-

ences between internal and external

steps of a changeover The easiest way

to do this is with an analogy In any form, automobile racing pit crews are

often tasked with changing tires on a race- car as fast as possible When a car comes

into the pits for tires, the crew removes

the wheels with the old tires from the

car They then mount another set of

wheels with new tires already mounted

and pressurized onto the car They do not take the time to remove the worn tires

Before/After During Machine

Measure the total changeover time hanøs6ø68685660656660060081ã60600666666666600S06B/)

|

move external steps outside of the changeover

L1 External

a2

from the wheel, put a new tire onto the

same wheel, air it, and balance it before

then remounting it back onto the race car What they have done is to convert

the process of mounting the new tire

from an internal step to an external step,

by having it already done on another wheel This is an example of a practice

that takes place in stage two of the SMED

process

Continuing the pit stop analogy, consider the air guns used to remove and

tighten the lug nuts of the wheel and the

lug nuts themselves NASCAR teams use glue to mate new lug nuts onto the

wheels that will be going onto the car

This way they do not have to place new

lug nuts onto each stud by hand They are already there and only have to be tight- ened with the air gun Similarly, crews

do not use one air gun to perform the work on all four wheels Each tire changer has its own air gun Both of these instances are examples of short-

ening or improving internal steps that

take place in stage three of the SMED process There is no practical way to eliminate something, lug nuts or in some series a single lug nut, that hold the

wheel on the car There is also no way

to eliminate the need for a tool to perform the change They therefore remain

LEAN MANUFACTURING

Trang 8

internal to the changeover, but are short-

ened as much as possible

An example of improving an external step in our analogy would be having the

four wheels with new tires clearly marked

so that the people performing the

changeover know exactly where they are

to be used This also takes place in stage

three of SMED Finally, the changeover

procedure must be documented and stan-

dardized so that it takes place the same

way every time no matter who performs

it A baseline should be taken before any

SMED activities so that a benchmark for

measuring improvement can be estab-

lished Pit crews constantly make video

recordings of pit stops and measure their

times, looking for additional opportu-

nities for improvement

The benefits to the bottom line of SMED are similar to that of TPM: im-

proved flow, lower inventories, and bet-

ter quality Whereas TPM focuses on

reducing unplanned downtime, SMED

focuses on reducing planned downtime

due to changeovers The less time that it

takes to change a machine from one prod-

uct to another, the more time there is

for production, resulting in greater capac-

ity for throughput

Six Sigma

At its core, the objective of Six Sigma is

zero defect processes The Six Sigma

name refers to the shape of a normally

distributed bell curve in statistics The

goal of Six Sigma is to design and develop

products and processes that produce 100

percent of parts within this Six Sigma dis-

tribution

Every process has variation in it Six

Sigma helps to define those character-

istics that are most critical to not only

the function of the part, but the run-

ability of the part in subsequent

processes The peak of the normal dis-

tribution is the optimum desired mea-

surement of the characteristic The

distribution of measurements from that

optimum will then fall within three sigma

deviation to either side of the optimum,

thus the name Six Sigma The tools used

to accomplish this are evaluation of

gauging methods including repeatabil-

LEAN MANUFACTURING

ity and reproducibility studies, design

of experiments practices, and statisti- cal process control

Many companies have started to blend their Six Sigma programs into their lean manufacturing programs The impact of

Six Sigma on lean is the production of : fewer defects with less stoppage and

adjustment of machines due to varia-

tions in the incoming parts Six Sigma focuses on reducing over-processing, overproducing, and defects Having

processes that are in control statistically and produce products exactly as they

are needed increases productivity

Kaizen culture

Another tool of a lean enterprise is the cultural tool of Kaizen It is the ongoing attitude that continuous improvement can be made The history of Kaizen again comes from Japan, but this time it was planted there by General Douglas

MacArthur following World War II Dur- ing the war, factories in the United States did not have extensive amounts of time

to shut down, retool, and rework plant layouts to produce war materials They :

had to begin production as best they could Out of necessity U.S manufacturing created the attitude of always

making small incremental improvements

After WWII, MacArthur promoted this

philosophy in rebuilding Japanese fac-

tories The Japanese took the philosophy,

refined it, and made it their own The

Kaizen culture is based on the five elements shown in Exhibit 4

Kaizen is more an attitude of the work force than it is a specific tool of lean manufacturing However, it is

an absolutely necessary shift from traditional Western attitudes that lead

us to “If it ain't broke, don’t fix it.”

A strong Kaizen culture must be in

place for all aspects of a lean enter-

prise to succeed Some of the prob-

lem solving tools utilized in an effective Kaizen culture are: fishbone diagrams,

five why analysis, Pareto charts, and fail-

ure mode and effects analysis (FMEA)

The benefits of a Kaizen culture to a

company’s bottom line are clear When

a workforce is focused and thinking of ;

Trang 9

24 :

: (Exhibit 4 Kaizen is Based on Five Elements

aspects of a company’s running

: improvement opportunities every day,

: the problem is not initiating continu-

: ous improvement, but prioritizing and

: allocating resources to effect the most : important improvements Reduction of : costs is an area hugely affected by a

: Kaizen culture In fact, Kaizen improve- : ments have been proven to have such a

: profound affect on costs that some domes-

- tic companies have been able to avoid

- outsourcing or relocating overseas to

: low-cost labor regions such as China and : Mexico and remain competitive."

Again, like VSM, Kaizen culture does : not have a direct effect on the bottom

: line of a company It is more the culture : of training everyone to continuously

: look for small incremental improve- : ments The collection of these improve-

> ments will affect every waste and

: therefore affect throughput, efficiency,

- and costs

: Hoshin Kanri planning

: Another tool made use of by a lean enter-

: prise is Hoshin Kanri planning, or Hoshin

: for short Kaizen is more of a cultural atti-

: tude and methodology for plant opera-

: tions; Hoshin planning is more a me-

: thodology for management to set forth

- a plan for the future Like Kaizen, it too

Quality Circles: Groups that meet to discuss quality levels concerning all

Improved Morale: Strong morale in the workforce is a crucial step to achieving long-term efficiency and productivity, and kaizen sets it as a foundational task to keep constant contact with employee morale

Teamwork: Kaizen aims to help employees and management look at themselves as members of a team, rather than competitors

Personal Discipline: A team cannot succeed without each member of the team being strong in themselves A commitment to personal discipline by each employee ensures that the team will remain strong

Suggestions for Improvement: By requesting feedback from each member

of the team, the management ensures that all problems are looked at and addressed before they become significant

`

was originally presented to the Japanese through an American after World War

II Hoshin is a more formalized version

of Edward Demming’s plan-do-check- act methodology It is the tool with which management communicates goals all the

way down through the different levels

of management

With Hoshin each staff member with responsibilities in every plant has annual goals Each of these goals can be tied directly to the goals of the superior to whom

he or she reports, and the same holds

true for the level above that This is the

case all the way through the chain of command All goals should directly support the company’s vision as set forth by

the CEO The process of developing these goals, communicating them, and measuring status is Hoshin planning Exhibit

5 shows how Deming’s plan-do-check-act

is applied in the Hoshin planning process

Another distinction between Kaizen

and Hoshin is the size of the improve-

ments or gains Kaizen focuses on small

incremental improvements that can be

made every day While these are a vital

part of the overall improvement plan of

a company and add up to be very sig-

nificant, they are not necessarily the

focus of Hoshin Hoshin is more focused

on the larger gains or step improvements

LEAN MANUFACTURING

Trang 10

( Exhibit 5 Process of Developing and Managing a Plan >

External Data Internal Data Customers Corporate goals |g

nè Ỷ

identify key Issues, develop objectives, goals, and implementation plans

2 Ỷ

lẽ

| Analysis of deviation | | Analysis of results |

eat

=

that require more planning and resources

Items that would typically fall into cap-

ital budget planning are ideal Hoshin

items That being said, the benefits of

Hoshin to a company’s bottom line are

similar to that of a Kaizen culture with

cost reduction being the largest area

impacted It helps to focus efforts of

resources to areas that are directly tied

to overall business objectives It also

helps to drive step improvements or

“breakthrough” improvements as opposed

to continuous incremental improvements

of Kaizen

Mistake proofing, standardized work,

d[T/Kanban/Heijunka

Another tool used within a lean enter-

prise is that of mistake proofing, some-

times called poka yoke, which means

error avoidance in Japanese It means

that quality is designed into the process

or product It guarantees the product

that goes to the consumer will be 100

percent defect free The truest form of

LEAN MANUFACTURING

sử

mistake proofing is done in product design If products are designed in such

a way that assembly processes cannot be done incorrectly, then true mistake proofing has taken place If, on the other hand, mistake proofing cannot be built into

the product, it is still beneficial to build

it into the process Automatic in-line quality checks are an example Sensors

checking part orientation in feed lines

are another example The benefit of uti- lizing mistake proofing in product or

process design is getting as close to zero

defects as possible, which is practically : perfect quality This pretty clearly reduces possibilities for scrap and thus reduces

costs and improves efficiencies directly :

impacting the bottom line

Standardized work is the tool that

helps to maintain lean achievements and

set the stage for continued improvement

It is what enforces and documents the results of the application of VSM, 5S, TPM, and SMED to increase flow By : having all who perform a job function

do it the same way every time, managers

Tiêu đề	Lean Manufacturing Principles And Their Application
Tác giả	Mehmet C Kocakiilah, Jason F Brown, Joshua W Thomson
Người hướng dẫn	Ph.D. Mehmet C Kocakulah
Trường học	University of Southern Indiana
Chuyên ngành	Cost Management
Thể loại	Bài luận
Năm xuất bản	2008
Thành phố	Evansville

Định dạng
Số trang	12
Dung lượng	1,87 MB