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A p p r o a c h T o H i g h V e l o c i t y M a n u f a c t u r i n g S y s t e m

Theory of Constraints andDrum-Buffer-Rope:

Presented by-

Wagh Sandeep Baburao

MTech 2nd Sem

Industrial Management

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The Theory of Constraints is based onthe premise that

Every real system, such as a business, must have

within it at least one constraint. If this were not the

case then the system could produce unlimited amounts

of whatever it was striving for, profit in the case of a

business..

Dr E Goldratt

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Constraints determine systemperformance

y A business having no constraintswould have infinite profit.

y Constraints may be-

Market

Capacity

Resources

Suppliers

Finance

Knowledge Or Competence

Policy

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Continue .

y Aconstraint is anything that prevents a system from

achieving higher performance relative to its goal (which for

a business is to make more money).

y Apolicy constraint is a policy, procedure, or even mindset

that prevents a company from making more money.

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Examples of Policy Constraints

y Salaries paid to workers are so low that the company cant keep

qualified workers.

y Buying raw materials strictly on the basis ofprice prevent getting

consistent good quality materials

y Repair of large portion ofHigh Way Road, the actual constraint

is Government acquisition policy - contract goes to lowest

bidder.

Policy constraints should be eliminated.

Drum-Buffer-Rope (DBR) applies to Market

and Resource Constraints.

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Finding the Constraint

y

What happens if A produces 5 per hour?

y What happens if A produces 1 per hour?

y So constraint is the weakest link in the system

WorkStation

A - 5B - 4 C - 3 D - 4

Market

2

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Finding the Resource Constraint(Assume the market exceeds productive capacity).

A- - - -

Constraint

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Identifying the Drum

A - 5 B - 4 C - 3 D - 4

Drum

C should be used as a drumbeating out a pace of

3 units per hour for the line to follow.

the physical constraint or the weakest link, which

will set the timing for the rest of the system may

called as a Capacity constraint resource (CCR).

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Locating the Buffers

A - 5 B - 4 C - 3 D - 4

DrumMaterial

(time) Buffer

SpaceBuffer

aterial release uration.he uffer rotects the ru , y ensuring that the

or -in- rocess arrives at the ell efore it is

sche ule to e rocesse .

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Tying the Rope from the Constraint toMaterial Release

Rope is the term used for the communication feedback to

the resources before the Drum, so that each of them

produces only the amount of inventory that the Drum can

complete.

A - 5 B - 4 C - 3 D - 4

DrumMaterial

(time) Buffer

SpaceBuffer

Rope

Shippingbuffer

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Materialrelease

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What if there is no Resource Constraint?

(The market demand is less than capacity)11

A - 5 B - 4 C - 3 D - 4

Rope Demand

Market- 2

Materialrelease

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TOC ProcessFive Focusing Steps

1. Identifythe constraint to the system.

2. Decide how to exploit the constraint to the system.

3. Subordinate all other resources to the constraint.

4. Elevate the system constraint.

5. If in any step, the constraint is broken, go to step 1. Don'tlet inertia set in.

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Identifythe Constraint to the system.

y Consider what is limiting the performance of the system,

whether the restraint is inside or outside the system

(resource, policy, market)

A - 5 B - 4 C - 3 D - 4

Constraint

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Decide how to exploit the constraint to thesystem.

y Exploit means to get most from the constraining element

without additional investment

y Find out the different possible ways to get maximum

benefit from constraint.

A - 5 B - 4 C - 3 D - 4

Drumt ri l

(tim ) Buff r

Sp cBuff r

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Subordinate all other resources to the constraint.

Local efficiency measures must be eliminated and

replaced by performance to schedule.

A - 5 B - 4 C - 3 D - 4

DrumMaterial

(time)Buffer

SpaceBuffer

Rope

Shippingbuffer

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Materialrelease

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Elevate the system constraint.

This might be a new worker or machine or it might be

offloading work to an existing machine.

A - 5 B - 4 C - 3 D - 4

DrumMaterial

(time)

Buffer

SpaceBuffer

Rope

Shipping buffer

C 3.5

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Materialrelease

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If in any step, the constraint is broken, go to step1. Don't let inertia set in.

y For example, change in market demand for a product, after

elevating the constraint one must not become complacent with

their action as there is an environmental (surrounding) change.

A - 5 B - 4 C 3.5 D - 4

DrumMaterial

(time)Buffer

SpaceBuffer

pe

Shipping buffer

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Materialrelease

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Conclusion

y TOC and DBR is helpful for identifying the core problem of

a complex system.

y TOC addresses the entire system as a chain or grid ofinterlinked chains.

y Result in continual improvement of the performance of the

entire system.

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THANK YOU

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