MEL420: Total Quality Management

Total Productive Maintenance

S G Deshmukh

Contents..

Imperatives

Concepts of maintenance

OEE

Pillars of TPM

Examples

Case study

Closure

Concept of maintenance

A set of various maintenance interventions (corrective, preventive, condition based etc.) and the general structure in which these interventions are foreseen.

Source: Pintelon and Waeyenbergh, 1999

Done By

A B C D

Routine Inspection

38 % 62 %

Periodic Inspection

5 % 93 % 2 %

Minor Repair

1 % 85 % 4 % 10 %

Shutdown 2 % 83 % 4 % 11 %

Practice of Maintenance Function in India

A : Operator B : Maintenance

C : Project/Construction D : Sub-Contractor

Source: Survey 1998 ( of 139 companies)

Generation Characteristics of Equipment

Maintenance technique & Philosophy

I (Before Second World War)

Simple, over designed , easy-to-repair

Basic & Routine

Reactive breakdown service

II (II WW to late 70’s)

Complex, Higher main. Cost relative to other op costs

Planned Preventive Maintenance

Time tested approach

III

(80’s onwards)

Continued complexity

Costly downtime

JIT systems

Rising demand for standards

Safety

Condition monitoring

Reliability Centered Maintenance

Computer aided

Multi-skilled workers

Reliability & availability

Proactive & strategic

Time line…1.. 1950’s

Manpower (simple)

“Fix it when it breaks” Maintenance is a production task

“necessary evil”

1950-1974 Mechanization (complex)

“I operate – You fix” Availability/longevity and PM

Maintenance is a task of maintenance department

“ technical matter”

Time line…2.. > 1975

Automation (more complex)

Reliability , availability, maintainability with safety, quality & environment

CBM, Multi-skiling

Maintenance is NOT an isolated function

“Profit contribution”

2000 onwards Globalization

Trend towards outsourcing

IT and Technology based

Maintenance is external and internal partnerships

”partnership” concept

Types of Maintenance.. Breakdown maintenance:

It means that people wait until equipment fails and repair it. Such a thing could be

used when the equipment failure does not significantly affect the operation or

production or generate any significant loss other than repair cost.

Types of Maintenance.. Preventive maintenance

It is a daily maintenance (cleaning, inspection, oiling and re-tightening), design to retain the healthy condition of equipment and prevent failure through the prevention of deterioration, periodic inspection or equipment condition diagnosis, to measure deterioration. It is further divided into periodic maintenance and predictive maintenance

Types of Maintenance..

Periodic maintenance (Time based maintenance - TBM)

Time based maintenance consists of periodically inspecting, servicing and cleaning equipment and replacing parts to prevent sudden failure and process problems.

Predictive maintenance

Service life of important part is predicted based on inspection or diagnosis, in order to use the parts to the limit of their service life. Compared to periodic maintenance, predictive maintenance is condition based maintenance. It manages trend values, by measuring and analyzing data about deterioration and employs a surveillance system, designed to monitor conditions through an on-line system.

Types of Maintenance Maintenance prevention

It indicates the design of new equipment. Weaknesses of current machines are sufficiently studied (on site information leading to failure prevention, easier maintenance and prevents of defects, safety and ease of manufacturing) and are incorporated before commissioning new equipment.

Remarks.. With profit margins decreasing , need for

good maintenance planning is obvious

In traditional organizations, maintenance is NOT given due importance.

It is a support function, non-productive and a non-core function adding very little value to business or bottom-line

Lack of connection between Maintenance and Profitability

Remarks..

The concept has moved from failure based to use-based maintenance and increasingly towards condition based maintenance

Greater emphasis on availability, reliability, and safety of the production facilities to meet competitive priorities of cost, quality, delivery and service

Different perspectives on TPM General movement on the part of businesses to try

to do more with less

An integrated life-cycle approach to factory maintenance and support

A comprehensive productive-maintenance delivery system

Way of working together to improve equipment effectiveness

Production driven improvement methodology

Intended to bring both functions together by a

combination of good working practices , team

working and continuous improvement

Need to exploit synergy between operation and Equipment

Design of Equipment/Installation/ Tooling operation/QC

Operation Education and Training

Equipment Centered Maintenance system

Overall equipment effectiveness (OEE)

= Availability x Rating x Yield

TPM Implications for various functions - Design - Manufacturing - Distribution - Customer feedback Quality - Through Design - Through Service - Through Operations Top Management Support Examples: Photostat Machine, Mixer etc

TPM … Strives for maximum equipment effectiveness

Establishes a total system of preventive maintenance for the entire life of the equipment

Participation by all sectors of the organization that plan, use and maintain equipment

Participation from top management to the frontline staff

Execution based on small group activity (SGA): team approach

TPM … according to JIPM (Japanese Institute of Plant Maintenance )

Establishes a corporate culture that will maximize system effectiveness

Organizing a practical shop-floor system to prevent losses before they occur throughout the entire production system life cycle with a view of achieving zero accidents, zero defects, and zero breakdowns

Involving all functions of organization including production, development, sales and management

Achieving zero losses through the activities of overlapping small groups

Remarks..

TPM is a Low Cost People Intensive System for Maximizing Equipment Effectiveness by Involving entire Company in a Preventive maintenance program

Operators are Expected to :

Understand how machine operate

Perform all Routine PM (Lubrication, Cleaning etc)

Inspect machine daily

Handle all Basic Repairs

TPM.. TOTAL ALL Encompassing by maintenance, production Individuals working together.

PRODUCTIVE Production of Goods, Services that meet or exceed Customers Expectations.

MAINTENANCE Keeping equipment, Plant in as good or better than the Original conditions at all times.

Goals

•Maintaining & Improving Equipment Capacity

•Maintaining Equipment for Life

•Using Support from all areas of the operations

•Encouraging Input from all employees

•Using Teams for continuous improvement

Major Loss Areas in a Typical

Plant

Planned downtime loss

Unplanned downtime loss

Idling and minor stoppages

Slow down

Process non conformities

Scrap

Equipment Utilization

Fundamental Premise - All equipment is available to be run 7 X 24

Equipment Utilization

24 hours x 7 days

Unscheduled

Time

Scheduled

Downtime

Running Time

7 Major Losses

Unscheduled Time

Is the time the equipment is available to run more production. This measures how much more output is available from the current assets if needed

Holidays

Mid-Week idle time

Weekends

Rate is reduced due to lack of scheduled demand

Stopped or Off State

Scheduled Downtime

Is the time allocated to scheduled activities on the equipment

Planned Maintenance / Shutdowns

Meetings / Training / Breaks

Trials

Planned Cleaning

Stopped, Off or Standby State

Major Losses

Breakdowns

Major Stoppages (Stopped, Off, Standby)

Change Over (Stopped, Off, Standby)

Start Up / Shut Down (Starting, Stopping, Aborting)

Performance Losses

Minor Stoppages (Standby, Stopped)

Speed Losses (Producing)

Defects

Quality Losses (Producing)

Running Time

Is the time that is left (Producing)

Asset ( Capacity ) Utilization This defines how effective an asset is being utilized

The inverse reveals how much more output is

available from the current asset if needed today.

Graphically Presented :

Asset ( Capacity )

Utilization =

Minor Stoppages

These are all stoppages less than 10 minutes

For example - equipment jams

Minor stoppages, although short in duration, are often a significant total loss when summed up

Minor stops highlight the area of operator frustration and increasing trends can identify deterioration of the equipment

The actual # of minor stoppages are to be recorded and we will back into the minor stoppage time.

Be very accurate in capturing the time for the other equipment losses !

Major Stoppages

These are all stoppages 10 minutes or greater

Equipment Failures - Are failures due to

Electrical

Mechanical

Other Failures

Stoppages due to packaging defects

Supplier related downtime

Warehouse downtime

For each major stoppage, each individual event should be recorded noting the duration

Major Stoppages cont..

The stoppage time is the total time from the equipment stopping, until it starts again.

These stoppages should be grouped into Equipment and Other failures.

Equipment failures are stoppages resulting from equipment deterioration.

It is the major responsibility of planned maintenance to eliminate Equipment Failures.

Over time, effective planned maintenance will reduce the mean time between failures (MTBF).

Change Overs

Change Overs are defined as any “change process” that needs to be managed on the production floor.

Change overs include size change overs, washouts, deal changes, line Sanitizations, etc.

Change Overs are considered to be non-value added because they contribute a significant amount of lost time that should be available for running more demand.

“Running” Change Overs The running change over time begins when the line

is shut down to start the change and ends when the line is re-started and the hourly case count has reached 50% of its scheduled rate.

Quality ( Defect ) Losses Quality Losses occur when equipment is used to produce

product, which is not immediately available for distribution.

All product which is not immediately released for distribution is considered a loss, because of the delay created in the supply chain.

Often some of the material can be release after inspection, but this increases inventory costs and reduces customer service.

Quality Losses are normally calculated.

The quantity of material initially held divided by the design rate produces the equipment time used to generate Quality Losses.

Example:

Initial Hold 2300 units

Design Speed 100 units/min

Quality Loss 23 min.

Start Up and Shut Down Losses

These losses occur when equipment has been shutdown. Often there are delays in equipment or man power preventing immediate resumption of production.

Examples include:

Start up after annual shutdown

Start up after holidays or weekends

Start up after lunches and breaks

Startup losses include the “ramp up time”. Therefor, the time required to achieve 50% of the design rate. This is measured in the same way as Changeovers.

If the break or other scheduled event exceeds the scheduled

down time the excess time is considered part of the Shutdown

Loss.

Computing Speed Loss Time and Minor Stoppage Time

Example

Available Time: 8 hours

Actual Production: 1100 Units

Designed Speed: 300 Units / hr

Actual Speed: 250 Units / hr

Losses accounted for:

Change Over = 1 hour

S/U & S/D = .5 hours

Major Stoppages = 1 hour

Quality = .5 hours

Computing Speed Loss Time and Minor

Stoppage Time example cont..

Step 1. Subtract the known losses from the available time

8 – 1 - .5 –1 - .5 = 5 hours of Remaining Time

Step 2. Calculate Speed Loss assuming no minor stoppages.

Speed Loss Factor ( SLF ) = 1 – 250 / 300 = .167

Speed Loss Time = Remaining Time * SLF

Speed Loss Time = 5*.167 = .83 hours

Step3. Calculate the total time for Speed Loss & Minor Stoppages.

To produce 1100 Units at the design speed should have taken

1100 Units @ 300 Units / hour = 3.67 hours of Theoretical Production Time

Challenges: Provide Usable Data and Information to the Users to Make

decisions.

Ensure Flexible Standardization for the User to define what is being captured and how it is used.

Stratification - Factory, Department, Line, Machine Center, Component.

Clarification - What caused the change of state:

User Input

Blocked

Starved

Electrical or Mechanical Failure

Protocol for the Myriad of Possibilities, Definitions and local Environments.

Other way of computing OEE

Formulas and Abbreviations A = Availability = MTBF/(MTBF+MTTR) MTBF: Mean Time Between Failure MTTR: Mean Time to Repair OEE = Ax PE x Q OEE = Overall equipment Effectiveness PE= Performance Efficiency= RE x SE RE = Rate Efficiency = (Actual Production Vol.) x Actual CT/ Actual Running Time SE = Speed Efficiency = Design cycle Time (DCT)/Actual Cycle Time (ACT) Q= Quality Rate = (Actual Production Volume – Defective Volume)/ Actual Production Volume

Equipment Effectiveness = M/C Availability x Perf. Eff. x Quality

= (PT-DT/PT)x (TCT/ACT) x (QP-D/QP)

PT= Planned Time

DT= Down Time

TCT= Theor. Cycle Time

ACT= Actual Cycle Time

QP= Quantity Produced

D= No. of defects

OEE… To three measurable:

Availability (Time), Performance (Speed) & Yield (Quality).

When the losses from

Time X Speed X Quality are multiplied together, thus resulting in OEE

Example XYZ Plant runs TWO shifts (2x8 = 16 hours), during each shift, 2 Hours of planned down-time:

Planned Running Time = 16-2x2= 12 Hours

110 minutes for set ups + 75 min for breakdowns/ repairs

Actual running time = 12x60-(110+75)= 535 min

A = Availability = (535/12x60)= 0.7431

Average daily throughput of machine = 830 units Actual cycle time= 0.6 min/part In theory it should take 830x0.6 = 498 minutes/ days parts to produce RE= Rate Efficiency= (Actual Prod Vol. x Actual CT)/ Actual run time = 830x0.6/535= 498/535 = 0.9308 Suppose machine is designed to produce 2 parts/min

=0.5min/part SE = Speed Efficiency = Design CT/Actual CT = 0.5/0.6= 0.8333 PE = RE x SE= 0.9308x0.833 = 0.7756 The machine produces 800 good units Quality rate = 800/830 = 0.9639 OEE = A x PE x P=0.7431 x 0.7756 x 0.9639 =0.5555 OEE = 55.55%

Typical Losses

Downtime for equipment set-up or adjustments

Downtime from Sporadic/Chronic equipment Breakdown

Idling & Minor stoppages

Reduced speed of Operations

Defects Caused by variability in equipment Performance

Reduced Yield caused by Non-Optimal operation

PILLARS for TPM Autonomous Maintenance Continuous Improvement Planned Maintenance Quality Maintenance-

Material Planning & Design

Education & Training Office TPM Safety/ Hygiene of Environmental

Control

Good Housekeeping (5-S)

A place for everything

Everything in its place

Everything Visible

Everyone involved in cleaning, checking & anticipating Problems

Philosophy of 5-S

Based on Japanese words that begin with ‘S’, the 5S Philosophy focuses on effective work place organization and standardized work procedures. 5S simplifies work environment, reduces waste and non-value activity while improving quality efficiency and safety

5-S : Housekeeping Practices

Sort means to separate needed tools, parts, and instructions from unneeded materials and to remove the latter.

Systematize means to neatly arrange and identify parts and tools for ease of use.

Sweep means to conduct a cleanup campaign.

Standardize means to conduct Sort, Simplify, and Scrub at frequent, indeed daily, intervals to maintain a workplace in perfect condition

Self-discipline means to form the habit of always

following the first four Ss.

Observations.. Once fully implemented, the 5S process

can increase morale,

create positive impressions on customers, and increase efficiency and organization.

Not only will employees feel better about where they work, the effect on continuous improvement can lead to less waste, better quality and faster lead times. Any of which will make your organization more profitable and competitive in the market place.

JAPANESE

ENGLISH

MEANING

TYPICAL EXAMPLE

Seiri

Sort

Organization

Throw away rubbish

Seiton

Systematize

Neatness

30-second retrieval of document

Seiso

Sweep

Cleaning

Individual cleaning

responsibility

Seiketsu

Standardize

Standardization

Transparency of storage

Shitsuke

Self-discipline

Discipline

Do 5 “S” daily

5-S • SEIRI

- Identifying Unnecessaries ,Getting Rid of the Unnecessary , and Stratification Management • SEITON - Functional Layout ; Deciding Where to Put What?

- Promoting Neatness • SEISO - Workplace and Equipment Cleaning

- The “To Clean is to Inspect” Attitude • SEIKETSU - Visual Management and and Tools and Methods for Visual Control • SHITSUKE - Habit Formation and Discipline , and Personal

Responsibility

Seiri: Sort or Organization. This is about

separating things that are necessary for the job from those that are not.

After

Before

TQM and TPM

Category

TQM

TPM

Object

Quality (Output and effects)

Equipment

(Input and

cause)

Means of

attaining

goal

Systematize the management. It is software

oriented

Employees

participation and it

is hardware

oriented

Target

Quality for PPM

Elimination of losses and wastes.

TPM Starters

BIRLA TYRES

GABRIEL

BHARAT SEATS

BAJAJ AUTO

M&M

BPL SANYO

SUNDARAM

CLATTON

SONA

SUNDARAM

FASTNERS

CLUTCH AUTO

VIKRAM CEMENT

HLL

Observations..

TPM is a manufacturing led initiative that emphasizes the importance of people,

a 'can do' and 'continuous improvement' philosophy and the importance of production and maintenance staff working together.

TPM & Other concepts

The major difference between TPM and other concepts is that the operators are also made to involve in the maintenance process. The concept of "I ( Production operators ) Operate,

You ( Maintenance department ) fix" is not followed.

Example As an example, in one manufacturing plant, one

punch press was selected as a problem area. The machine was studied and evaluated in extreme

detail by the team. Production over an extended period of time was used to establish a record of productive time versus nonproductive time.

Some team members visited a plant several kms away which had a similar press but which was operating much more efficiently. This visit gave them ideas on how their situation could be improved.

A course of action to bring the machine into a "world class" manufacturing condition was soon designed and work was initiated.

Example .. contd The work involved taking the machine out of

service for cleaning, painting, adjustment, and replacement of worn parts, belts, hoses, etc.

As a part of this process, training in operation and maintenance of the machine was reviewed. A daily check list of maintenance duties to be performed by the operator was developed. A factory representative was called in to assist in some phases of the process

Example .. contd

After success has been demonstrated on one machine and records began to show how much the process had improved production, another machine was selected, then another, until the entire production area had been brought into a "world class" condition and is producing at a significantly higher rate

Learnings..

Note that in the example above, the operator was required to take an active part in the maintenance of the machine. This is one of the basic innovations of TPM.

The attitude of "I just operate it!" is no longer acceptable. Routine daily maintenance checks, minor adjustments, lubrication, and minor part change out become the responsibility of the operator.

Extensive overhauls and major breakdowns are handled by plant maintenance personnel with the operator assisting. Even if outside maintenance or factory experts have to be called in, the equipment operator must play a significant part in the repair process

Direct benefits of TPM

Increase productivity and OPE ( Overall Plant Efficiency ) by 1.5 or 2 times.

Rectify customer complaints.

Reduce the manufacturing cost

Satisfy the customers needs by Delivering the right quantity at the right time, in the required quality. )

Reduce accidents.

Follow pollution control measures.

Indirect benefits of TPM

Higher confidence level among the employees.

Keep the work place clean, neat and attractive.

Favorable change in the attitude of the operators.

Achieve goals by working as team.

Horizontal deployment of a new concept in all areas of the organization.

Share knowledge and experience.

The workers get a feeling of owning the machine.

Industry Practice Ford, Eastman Kodak, Dana Corp., Allen Bradley, Harley Davidson; these

are just a few of the companies that have implemented TPM successfully. All report an increase in productivity using TPM.

Kodak reported that a $5 million investment resulted in a $16 million increase in profits which could be traced and directly contributed to implementing a TPM program.

One appliance manufacturer reported the time required for die changes on a forming press went from several hours down to twenty minutes! This is the same as having two or three additional million dollar machines available for use on a daily basis without having to buy or lease them.

Texas Instruments reported increased production figures of up to 80% in some areas. Almost all the above named companies reported 50% or greater reduction in down time, reduced spare parts inventory, and increased on-time deliveries. The need for out-sourcing part or all of a product line was greatly reduced in many cases.

Birla Cement, TVS, HLL, Tata Steel, Rallis are some of the Indian companies going for TPM

Tata Steel conferred “The TPM Excellence Award – 2004” by Japan Institute of Plant Maintenance (JIPM)

-November 15, 2004

Four units of Tata Steel have been adjudged winners of the ‘TPM Excellence Award - 2004’ by Japan Institute of Plant Maintenance (JIPM). Every year the institute confers the TPM awards to applicants from all over the world, who are doing remarkably well in implementing TPM to increase plant efficiency. This is the first time in India, when a hot strip mill, a bearings plant or a precision tube mill has achieved the distinction of getting the JIPM TPM Excellence Award.

Press Release of Tata Steel (Contd)

Competitiveness, sustainability and the need to maintain its position as the lowest cost producer in the world had prompted Tata Steel to adopt various improvement initiatives which helped the company in achieving its goal of being the lowest cost producer of steel in the world. As part of this effort, in 1999-2000 the company undertook to implement “Total Productive Maintenance” or TPM at some of its critical units. These were the hot strip mill, precision tube mills (tubes division), bearings division (Kharagpur) and the Wire Rod Mill.

The prime objective of deployment of TPM at Tata Steel has been to achieve a status of “Zero Accident”, “Zero Breakdown”, “Zero Customer Complaint” and “Zero Defect”. The remarkable deployment results of TPM in the four units had encouraged Tata Steel to challenge the coveted ‘TPM Excellence Award - First category” of JIPM, for all these four units. Buoyed by the significant improvements achieved in these units, the deployment of this TPM philosophy has now been done at all the manufacturing and support service areas of the company including mines and collieries. As of now, more than 50 units of the company have initiated the TPM journey and are at various stage of its deployment.

Office TPM

Office TPM should be started after activating shop floor TPM

Office TPM must be followed to improve productivity, efficiency in the administrative functions and identify and eliminate losses. This includes analyzing processes and procedures towards increased office automation.

Major Losses in office Office TPM addresses twelve major losses. They are

Processing loss Cost loss including in areas such as procurement, accounts,

marketing, sales leading to high inventories Communication loss Idle loss Set-up loss Accuracy loss Office equipment breakdown Communication channel breakdown, telephone and fax lines Time spent on retrieval of information Non availability of correct on line stock status Customer complaints due to logistics Expenses on emergency dispatches/purchases

How to start Office TPM? Providing awareness about office TPM to all support

departments

Helping them to identify P, Q, C, D, S, M in each function in relation to plant performance

Identify the scope for improvement in each function

Collect relevant data

Help them to solve problems in their circles

Make up an activity board where progress is monitored on both sides – results and actions along with Kaizens.

Fan out to cover all employees and circles in all functions.

P Q C D S M in Office TPM

P – Production output lost due to want of material, Manpower productivity, Production output lost due to want of tools.

Q – Mistakes in preparation of cheques, bills, invoices, payroll, Customer returns/warranty, Rejection/rework in POs/job work, Office area rework.

C – Buying cost/unit produced, Cost of logistics – inbound/outbound, Cost of carrying inventory, Cost of communication, Demurrage costs.

D – Logistics losses (Delay in loading/unloading) Delay in delivery due to any of the support functions Delay in payments to suppliers Delay in information

S – Safety in material handling/stores/logistics, Safety of soft and hard data.

M – Number of kaizens in office areas.

TPM Part of Strategy Proactive to eliminate breakdowns Planned & Controlled expenses with specific measures Maintenance as a part of equipment selection & design Carefully Planned Inventory Everybody’s Job Generates & Implement Ideas Quality – Everybody’s Job! Part of manufacturing team TQC+TEI = TPM

Some Comments

Education and knowledge of TPM

Ignoring the yardstick

TPM is NOT a maintenance system documentation

Reset priorities

TPM cannot be implemented overnight

Address all human issues

Closure…

TPM is a people initiative

Involvement of all

Support from top management

It is NOT a maintenance program but to be treated as a plant wide philosophy in the spirit of continual improvement