Part 2

Seven Wastes

This programme is funded by the European Union

under an Agreement with the Government of the Republic of Trinidad and Tobago

The essence of lean manufacturing is identifying and eliminating waste.

All processes either add value or waste.

Through waste elimination, opportunities

Lean Manufacturing Breakfast Seminar 

And The Tools to Fight Them 

Waste  

   to create competitive advantages. 

Value

Waste

MaterialTimeEquipmentFinished Goods

Reduced SpeedBreakdownsIdling and Minor StoppagesDefects, ReworkOverproduction

= what the customer is prepared to pay for 

Waste 

Hidden Costs 

Set  up and changeovers

1. Overproduction

2. Waiting

3. Transportation

4. Processing

5. Motion

6. Defects

(After Womack Jones Roos “The Machine That Changed The World: The

Story of Lean Production”, 1990; Womack Jones “Lean Thinking”, 2003)

Overproduction is the production of an item before it is actually required.

Overproduction drives high inventory levels and associated costs, long throughput times, and delays in identifying problems.

The ‘Seven Wastes’ in Manufacturing 

7. Inventory 

8. Underutilized People 

1. Overproduction 

Overproduction has a negative impact on the smooth flow of materials, thus on productivity, flexibility, quality and cost.

Overproduction leads to all other forms of waste.

“Just in Case production”

‘Turn off the tap’

Reveales underlying problems

Order-based scheduling

Improve setup/changeover capacities

Overproduction 

Countermeasures 

2. Waiting 

Waiting for the next process step is typical for batch-and-queue production.

Waiting is a major cause of production and sales bottlenecks and high inventory levels of raw material, parts, sub-assembly and finished goods storage not adding value to the business.

Waiting is mostly due to long runs, poor production flow, and long shopfloor distances.

Redesign production flow

Interfaces

Shorten production cycles

Kanban Scheduling

Teamwork

Waiting 

Countermeasures 

Unnecessary movement of materials, people and equipment has a negative impact on product quality and costs.

Excessive walking, bending, lifting and handling materials has a negative impact on staff’s health and safety.

Transportation is a cost factor, and excessive movements add no value to the business.

Process Mapping

Ergonomics

Workplace Redesign

Shorten distances and processes

3. Transportation and Excess Motion 

Transportation and Excess Motion 

Countermeasures 

Teamwork

Overprocessing is processing an item to a standard that exceeds customer requirements.

Overprocessing implies overkill in technologies, processes, and workforce utilisation.

Inappropriate technologies result in large space allocations, poor plant layouts , low machine efficiency rates, and high depreciation costs.

Overprocessing drives high asset utilisation to recover capital investments, hence inflexibility and overproduction.

Appropriate Technology

Appropriate Automation Levels

4. Processing 

Processing 

Countermeasures 

Flexible Options

Total Productive Maintenance

Teamwork

Defects result in rework, adaptations, and scrap.

Defects drive costs associated to material, production and capacity losses, rescheduling, quality control etc.

Defects are the primary metrics in Six Sigma strategies.

Quality Control

5. Defects 

Defects 

Countermeasures 

Benchmarking

Continuous Process Improvement

Teamwork

Inventory levels are a yardstick to measure the extent of waste in the production system.

6. Inventory 

Excess inventory utilises shop floor space,     obstructs production flows, increases throughput time, inhibits communication, complicates the tracing of defects.

Work in Progress inventory levels correspond   directly to the levels of overproduction and waiting.

Inventories devour capital, and inventory    reductions alone provide the returns on lean manufacturing investments.

Inventory 

Countermeasures 

Redesign production flow

Interfaces

Order-based scheduling

One-Piece-Flow

People are hired for specific jobs and functions, but beyond these, their know-how, experience and creativity are underutilised and generally misunderstood.

People’s motivation and problem-solving skills are not or not sufficiently encouraged.

The value of transparency, communication and training is mostly underestimated.

People’s involvement is key to any kind of improvement.

7. Underutilized People 

Underutilized People 

Management by Objectives

Performance Appraisal, Bonus System

Teambuilding

Training

Multiskilling

Lean manufacturing’s basics to eliminate

Value Stream Mapping

Flow

Countermeasures 

waste and focus on processes that add value 

Cellular Production

Pull Scheduling

Continuous Improvement

Typically, as much as 60% of operations in small and

medium sized enterprises does not add value to the

Value Stream Mapping helps to identify the current

flows of material and information in processes for a

range of products, highlighting the opportunities for

improvement that will most significantly impact

performance.

Value Stream Mapping 

final product and can be eliminated. 

Product C

Value Stream Mapping

Objectives:

Increase customer responsivenessIdentify opportunitiesSpecify added value

Process Mapping

Value Stream Products/Processes Matrix 

Products 

Processes 

Functional Focus 

Value Streams 

Product A 

Product B 

Broad perspective of value streams  

Objectives:

Identify wastesSpecify improvementsStreamline processesStandardize stepsBuild consensus

Process Mapping Example

Process Mapping - Current, Future State

Tools:

Takt Time Calculation

Sequential process charts  

Flow 

Key Objective:

Align processes to suit customer requirements 

Overall Equipment Effectiveness Set up reductionStandardised WorkLevelled ProductionWork BalancingPull Scheduling, KanbanError Proofing5 S, Visual Controls, FiFo

Monthly customer

demand translated

into a daily mix of

products

Flow - Cellular Production

Flow

Flow – Levelled Production 

Example

Customer Demand = 500 parts per week = 100 parts per day

Cycle Time = 1,400 seconds

Crew Size = 1,400 / 242 = 5.6 = 6 staff, strive for cycle time

reduction as to arrive at crew size of 5 staff

Takt Time 

Takt Time  =    Production Time Available

                     __________________________________

                              Customer Demand 

Crew Size           =   Sum of Manual Cycle Time

                     __________________________________

                                     Takt Time 

Production Time Available  = 420 mins per day

Takt Time = 420 / 100 = 4.2 minutes 

Overall Equipment Effectiveness 

OEE

Example

Availability 86%, Productivity 60%, Quality 96%

OEE = 0.86 x 0.6 x 0.96 x 100 = 49.5%

Little or no inventory

Supplying the production process with the right part, at the right time, in the right amount

First in, first out flow

When a preceding process does not receive a request, it does not make parts.

Small buffers accomodate minor fluctuations, yet allow continuous flow.

= Availability/Uptime x Productivity/Speed x Quality % Rates 

Typical:  50-60% 

World Class:  85% 

Just in Time 

Pull Scheduling

Seiri - Sort, HousekeepingSeiton - Set in order, Workplace organisationSeiso - Shine, CleanupSeiketsu - StandardizeShitsuke - Sustain

Clearout & Classify – clear up spaceConfigure – Standard layoutsClean & Check – ensuring equipment fit for purposeConformity – standardize, communicate new standardsCustom & Practice – make it a habit and review frequently

5 S / 5 C 

Metrics 

Primary Metrics Six Sigma: Defects

Primary Metrics Lean: Time 

Principles for Lean Metrics

Keep it simple. Use metrics that are easy to compile and update. Limit the metrics. Metrics only have to signal an alert; more than 3-6 daily or weekly metrics would not get monitored sufficiently. Use tripwires. Daily or weekly metrics only need to alert you that a problem exists; drill down as problems arise, then adjust where appropriate.

Adopting Best Industry PracticesSetting StandardsQuality ManagementContinuous Improvement

DefineMeasureAnalyzeImproveControl

Plan

Define a problem, an opportunityAnalyze the situation. Brainstorm on causes and possible solutions, determine best approach and best possible corrective actions. Prioritize.

Benchmarking 

Deming Cycle – Plan Do Check Act (Project Mgmt) 

DMAIC Process Variant (Six Sigma)

Develop an implementation plan

Do

Implement change/testDocument processesCollect data

Check

Analyze data/resultsMonitor trends/levelsCompare results against plan

Act

If results are as expected, conclude/adopt > benchmarkIf results are not as expected, revise planDocument processes

Continuous Improvement 

Establishing an environment that fosters continuous

definition, measurement and improvement of key

processes driving performance. 

Overproduction drives high inventory levels and associated costs, long throughput times, and delays in identifying problems.

Overproduction has a negative impact on the smooth flow of materials, thus on productivity, flexibility, quality and cost.

Waiting is a major cause of production and sales bottlenecks and high inventory levels of raw material, parts, sub-assembly and finished goods storage not adding value to the business.

Unnecessary movement of materials, people and equipment has a negative impact on product quality and costs.

Excessive walking, bending, lifting and handling materials has a negative impact on staff’s health and safety.

Inappropriate technologies result in large space allocations, poor plant layouts , low machine efficiency rates, and high depreciation costs.

Overprocessing drives high asset utilisation to recover capital investments, hence inflexibility and overproduction.

Defects drive costs associated to material, production and capacity losses, rescheduling, quality control etc.

Excess inventory utilises shop floor space,     obstructs production flows, increases throughput time, inhibits communication, complicates the tracing of defects.

Inventories devour capital, and inventory    reductions alone provide the returns on lean manufacturing investments.

People are hired for specific jobs and functions, but beyond these, their know-how, experience and creativity are underutilised and generally misunderstood.

Use tripwires. Daily or weekly metrics only need to alert you that a problem exists; drill down as problems arise, then adjust where appropriate.

Analyze the situation. Brainstorm on causes and possible solutions, determine best approach and best possible corrective actions. Prioritize.

Waiting is a major cause of production and sales bottlenecks and high inventory levels of raw material, parts, sub-assembly and finished goods storage not adding value to the business.

Excess inventory utilises shop floor space,     obstructs production flows, increases throughput time, inhibits communication, complicates the tracing of defects.

People are hired for specific jobs and functions, but beyond these, their know-how, experience and creativity are underutilised and generally misunderstood.

Waiting is a major cause of production and sales bottlenecks and high inventory levels of raw material, parts, sub-assembly and finished goods storage not adding value to the business.