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Applicability of Single Minute Exchange of Die (SMED) Philosophy for

Non- Manufacturing sectors.

*Vivek P. Nerurkar

Abstract:

Value Creation is a key word in every aspect of Business, be it Manufacturing or Service sectors.

It indirectly leads to practices which eliminate or reduce waste, during manufacturing and also

while delivering the product / service. Conventionally, Single Minute Exchange of Die (SMED)

is a popular tool confined to Lean Manufacturing that to Batch type production.

SMED empowers the user to distinguish and identify activities as Internal (Activities which can

be conducted when process under consideration, is stopped. E.g. the Press is stopped when die is

being adjusted and set on the bolster) and External (Activities which can be conducted when

process under consideration is on i.e. when previous batch is on or when next batch is being

produced. E.g. the Press is operating, when die required for next batch is being cleaned, lubricated

and prepared.)

This paper is an attempt to project SMED as a resourceful tool, which can go beyond

manufacturing. Examples from various industry Domains like Railways, Construction, Loan

Finance with particular emphasis on Supply Chain, Passenger Transport through Railway, Pre-

approved Loans are considered here. This may possibly lead to paradigm shift of looking at

SMED, more than just as Lean Manufacturing (that to Batch type Production) tool. This will also

open opportunities to extract benefits of SMED tool in other fields like Marketing, Financial

Services etc. with some local customisation or innovation.

Key words: Value Creation, Lean Manufacturing, Internal Activity (IA), External Activity (EA),

Innovation

*Prof. Vivek P. Nerurkar, Assistant Professor, Lala Lajpatrai Institute of Management, Mumbai.

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Introduction:

Conventional understanding of SMED

SMED stands for Single Minute Exchange of Die, a systematic approach to change-over and set-

up time reduction. SMED is an acronym that made its way into industrial term for decades now.

Its origins is in Japanese automotive industry of the 1950s when Toyota Production System

pioneers led by legendary Shigeo Shingo observed operations on shop floor.

Exchanging a die (weight in tons) of a huge press took hours, letting the machine – a valuable

resource – stopped and producing no added value. Diminishing the changeover time, allowed to

convert wasted time into value adding time. “Single Minute”, does not mean in less than a minute,

but in a time measured on a single digit, thus between 0 and 9 minutes, or put in the pioneers’

spirit in less than 10 minutes.

SMED is one of the Lean Manufacturing tool to reduce waste in manufacturing.

• Internal activities: Activities which can be conducted when process under consideration,

is stopped.

• External activities: Activities which can be conducted when process under consideration

is on i.e. when previous batch is on or when next batch is being produced.

After analysing the changeover process, the thorough elimination or reduction of unnecessary

tasks and better organization, cut the duration of a changeover from hours to minutes.

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Fig.1 Piggyback Transportation (RORO)

Fig.2 Push- Pull arrangement

Fig.3 Ready Mixed Concrete

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Existing applications – Perceived through SMED Paradigm

Classic Changeover

Most often, the changeover happens like the time chart below shows. It starts when the last part

from actual production batch is finished and ends when the first part from new production batch

is ready to be processed at normal pace.

Breakdown of changeover process:

(Machine stopped)

The machine is usually stopped and all changeover operations happen in sequence, while the

machine is stopped. The machine will start again only after completion of adjustments and trials.

Sometimes after quality check and when the appointed staff gives “it’s ok”.

Understanding of SMED for typical Press shop environment:

Consider a change over process, comprising of ten activities. It is represented diagrammatically

on time scale, as shown below-

Four steps to SMED

By hunting down all causes of time waste, the SMED team advices a sequence of four steps to

reduce change-overs.

Finishing

actual

batch

Dismount

tools

Change

tools Adjustments Trials

Process

new batch

Change over

steps

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The first obvious thing noticed by the engineers was that during changeovers and setup the

machine was stopped, even for operations that were totally independent of the machine itself, like

preparing tools, dies or various supplies.

This led to the first step of the SMED approach:

Step1- Discriminate operations that must be done while machine is stopped, called internal

activity (IA). Activities which are carried out while machine runs, are called external activity

(EA).

For a typical press shop set up environment, External Activities are related to following areas:

Tools, parts

Instructions

Lifting material

Pre-assemblies

Activities related to above areas, can be treated as E.A. This is addressed in Step 2.

Step 2- Convert IA into EA and suppress non-value adding operations. Here, apparently IA are

converted in to EA. It leads to immediate effect of reduced time, for which machine (or process)

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is stopped.

Step3- Simplify and standardise IA. Which further reduces process time, as shown below.

For a typical press shop set up environment, time required for IA can be reduced by simplifying

fittings and tightening, in ways mentioned below-

Suppress fittings and tightening partially or even totally

Minimize “turning” movements: they request several grasp-release motions!

Fit at once, in a single motion

Use blocks, jigs, templates

Standardize tools, types and size of screws, nuts

Go for ideal: use only one type of screwdriver or wrench, challenge to suppress all tools

Once the die, fixture or template for the new batch is set, it is usual to have several adjustments

to go through. These adjustments are also time-consuming and extending the duration of machine

stoppage. Adjustments are to be considered as waste. Would the setting be done properly, the

adjustments wouldn’t be necessary.

Set standard values

Find out adjustment-less methods through physical means, like stoppers, guides, blocks

Design custom-made tools if necessary

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Step 4- Simplify and standardise external activities (EA). Suppress adjustments and trials.

By improving and standardisation with respect to Tools and parts, Instructions, Lifting material,

Pre-assemblies we can reduce EA time.

(Following pages narrate various cases, related to SMED from Supply Chain, Finance, and

Transportation)

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Cases:

Process improvement cases perceived through SMED paradigm:

1. Truck loaded with goods Fig. 1, directly moved through railway flat wagons-

Piggyback transportation

Here moving of goods is “Process under consideration”.

In conventional mode, goods are moved through trucks (near source) to railway yard.

Then they are unloaded from trucks and loaded on railway wagons. As they reach

destination, goods are unloaded from wagons and loaded back on trucks (at destination)

there. (See block diagram below)

Conventional mode:

Modified mode: Piggyback transportation (RORO)

Loading and

unloading goods

from truck AT

SOURCE

Loading and

unloading goods

from Railway

wagon

Loading goods on

truck AT

DESTINATION

Loading goods on

truck AT

SOURCE

Loading truck on

Railway flat

wagon

Moving truck from

flat wagon TO

DESTINATION

Resource

Required

for Loading

and

unloading

Resource

required for

unloading

and loading

Resource

required for

unloading

and loading

Resource

Required

for Loading

and

unloading

Resource

required for

unloading

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From Supply chain point of view, as soon as goods/ consignment stop moving, cost

component is bound to increase.

Here, activities required for transporting goods, are classified as Internal and External,

based on goods movement. The activity which stops goods’ movement is Internal Activity.

And activities which can be continued, even when goods are moving towards destination,

are External Activities.

Loading and unloading activity is Internal. Practically, if any of the two is delayed by some

or other reason, core objective of efficient transportation is affected adversely.

In conventional mode, more of loading and unloading poses a challenge for efficient

transportation.

In modified mode, loading and unloading is reduced. That results in efficient transportation

and less resource requirements.

Advantage: The carriage of trucks on RORO (Roll On Roll Off -

Piggyback transportation) increases trucker earnings by improving turnaround time --the

transit time of trucks in the Mumbai–Goa section on RORO is 30% of that on road.

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2. Railway diesel engine is shunted in “Push –Pull” arrangement Fig. 2, to save time while,

changing direction of the train journey-

In this case, “changing direction of train journey” is process under consideration. Activity

which stops or delays direction of train’s journey, is Internal Activity. When the train

completes journey from destination 1 to destination 2, in normal arrangement, diesel engine is

loosened and taken to other end of the train. Here train is ready to move from destination 2 to

1.

This normal arrangement takes time for loosening and shunting the engine, moving it from

one end to another. It also requires clear line, for engine to move from one end to another.

New arrangement positions the diesel engine at the centre of train. Control cabins are provided

at either ends of the train. Here we avoid time loss in loosening, shunting and engine

movement. Corresponding saving of fuel is observed. Internal Activity is converted in to

External Activity.

Normal arrangement – Engine shunted at fore front of the train

Here, movement of the engine from End2 to End1 becomes Internal Activity (IA).

PUSH-PULL arrangement- Engine is shunted at the centre, with control cabins on either

sides of the train.

Engine movement (shunting) becomes External Activity (EA).

Journey

completed from

destination1 to

destination 2

Engine is

loosened

from End 2

Engine is

moved to

another

track

Engine is

moved to

End 1

Engine

shunted at

End 1, ready

for return

journey

Engine is

shunted at

the centre

Journey

completed from

destination1 to

destination 2

Ready for

return journey

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3. Ready-Mix Concrete (RMC):

The process of RMC Fig. 3 is offering many advantages to construction industry. Few of

its advantages are – Consistent quality, faster process, no wastage of material, storage of

materials at site is not required.

If we look at this application through paradigm of SMED, then we can compare RMC

against On-site concrete with the help of following block diagram-

On-site concrete

Here making of concrete is Internal Activity (IA).

RMC

Here making of concrete is External Activity (EA).

Advantage: 10 to 12 % reduction in cement consumption. Saving storage place.

Improved quality of mixture. Better quality control.

Raw material

storage at site

Raw material

taken in

proportion at site

Mixing is done Concrete is

used at location

Ready Mixed

concrete from

vendor

Concrete is used

at location

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4. Pre-approved loans- Company Bajaj Finserv offers financial service of pre-approved

loans for various personal needs. It can be perceived through SMED Paradigm.

Conventional procedure for loan sanctioning -

Internal Activity

Here activity of loan sanctioning is Internal Activity. It is initiated when client requires

loan for purchase of certain goods. Till loan is not sanctioned, purchasing activity gets

delayed.

Pre-approved Loan process –

Here activity of loan sanctioning is carried out at a convenient time, well ahead of actual

goods purchase. So it becomes External Activity (EA). When goods are to be purchased,

pre-approved loan is immediately disbursed.

External Activity

Advantage: Opportunity to purchase can be timed, Hassle-free loan disbursement,

Cycle time for loan sanctioning gets reduced.

Loan

application

from client

Documents

receiving and

verification

Loan

eligibility

decided

Loan

sanctioned

and ready to

be disbursed

Actual loan

disbursement

against goods

purchased

Loan

application

from client

Documents

receiving and

verification

Loan

eligibility

decided

Loan

sanctioned

and ready to

be disbursed

Actual loan

disbursement

against goods

purchased

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Conclusion:

From the discussion and various examples mentioned above, it will be very interesting to

understand and perceive SMED tool applicable to non-manufacturing sectors-

1. Wherever we can apply process approach, implementing SMED can lead to value addition.

2. Various scares resources like time, space, money are conserved.

3. Cycle time to deliver product/service gets reduced.

4. In all, benefits of SMED can prove boon to non-manufacturing sectors also, with some

local customisation or innovation.

Further scope for research:

In this paper, an attempt is made to use SMED tool for non-manufacturing sectors. SMED

philosophy can prove an avenue for bettering processes (value creation) in non-manufacturing

sectors. For this, a case/ issue from non-manufacturing sector can be studied in depth, to take this

concept further, benefiting non-manufacturing sectors.

Reference:

1. http://thinkinglean.com/Volume_3_Issue_2_icerik156.html

2. http://www.lafarge.in/wps/portal/in/3_A_2_2-Site_mix_vs_ready_mix

3. http://articles.economictimes.indiatimes.com/2003-05-09/news/27548322_1_freight-

container-traffic-railway-plan

4. Book- Title: Gemba Kaizen by Masaki Imai