A Practical Guide to Implementing Operator Based...

A Practical Guide to Implementing Operator Based Reliability (OBR) Reliability

May, 2009

By:

Torbjorn Idhammar

IDCON, Inc. 7200 Falls of Neuse Road

Suite 200

Raleigh, NC 27615

http://www.idcon.com

1

A Practical Guide to Implementing Operator Based Reliability (OBR)


By Tor Idhammar,

President, IDCON, INC

– A Reliability and Maintenance Management Consulting firm.

Operator based Reliability can be implemented in many different

ways. This paper is meant to describe some of the key concepts

and implementation challenges for plant/ mill/ mine leaders

when endeavoring into OBR.

Involving operators in reliability is technically very simple, but it

can be very challenging from a people perspective. Meaning that

it is fairly easy to figure out what to do and how to do it, while it

in many cases it can be almost impossible to get people to

actually execute the tasks. It is therefore worthwhile to spend

considerable thinking time on the problem, “How can we, as a

company, get people to do, what we want them to do, with

regards to OBR”. The answer to that question will differ

between countries, industry, and local culture, but we (IDCON) will share some of our

experiences and hope those can help.

Involvement

People don’t mind change, but they do mind being changed by others. So one of the basic

concepts in implementing OBR is “involvement”. Involvement needs to be though through

before starting an OBR implementation because the more people involved the longer it takes to

decide what and how to do something. At the same time more involvement creates more

ownership and acceptance. As a leader, you therefore need to decide, when to involve people

and to what extent to get the right balance. In general, leadership should take decisions on

WHAT the right things to do are. For example, leadership should decide the scope and results

wanted from OBR, while smaller groups can be assigned to come up with exactly HOW certain

tasks are done, while many people can help building the data for the work system once the

design is done.

What will the OBR work system look like when it is complete?

Before people are assigned to tasks, it is really important to paint a picture of what the finished

product will look like. If you, as a leader, don’t paint a clear picture of what OBR will look like

when it is completed, how can you expect your organization to move in the right direction? The

sad truth is that most leaders just say they want OBR and each individual make up their own

version of what that looks like. Below are some practical examples listed of what to think of:

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There are many more

questions to consider, but

by answering questions

like the example ones

above will help paint a

picture for the

organization. Leaders

should paint the picture.

Leaders are responsible

for setting the direction

the plant/ mine/ mill is

going.

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*Continuing this article, we will talk about inspections, cleaning and operations practices since that usually is the key focus for OBR, however, we suggest your plant take plenty of time thinking about including operations involvement in: • Scheduling and prioritization of maintenance work • Root cause analysis

Once the picture is designed, don’t forget to communicate this future state to the organization.

Many organizations don’t have effective communication channels. The typical communication

is that top management communicate to middle management and it is then assumed that middle

management will spread it to lower management and so on. Both the content and the extent of

the message are almost always poorly communicated. Try to make sure the future vision is

clearly and professionally communicated.

Implementation Plan

The implementation plan will not describe what the

final product will look like. The implementation plan

will describe the tasks that are needed to get there.

Most implementation plans usually exist of many small

tasks, I have provided some important tasks to consider

in this paper.

A simple, yet structured documentation process

There is not enough room in this article to explain the

full documentation process, so, we have opted to list a

few key points. Feel free to email us

([email protected]) or call me (+1 919 723 2680) to

discuss if you have questions:

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http://www.idcon.com/pdf-doc/106R-COUPLING-GEAR-CMS-106R-Version-1.2.pdf

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IDCON has found it useful to base operator inspections on standard instructions for standard

components. Each instruction can consist of a number of key words. The standard instruction is

what the inspector carries in the field on a piece of paper or handheld computer. An electrical

motor standard inspection may be:

Air intake. Detailed cleaning. Water/ Humidity. Motor base. Electrical. Greasing.

Temperature. Noise. Vibration. CMS100R (each KEY is found in column 1 of CMS

document, what in column 2, why in column 3, see appendix)

The KEY WORDS are meant to be a

memory jogger only, not an instruction.

If the inspector doesn’t know how or

why to do the inspection, he/she will

refer to the CMS. The CMS will explain

exactly HOW and WHY each inspection

(KEY WORD) is done. The CMS can

be available in a notebook in the control

room or other general area, or they can

be stored on a common server as PDFs.

What about measuring points?

In our opinion the general rule is to only

collect measuring points that will be

used. It is common to se plants collect as many measuring points as they possibly can for each

component. When the OBR system is launched, no one ever looks at the data. Do not collect

more measuring points than the plant can handle and have time to analyze. Why not start with

25 measuring points in each area and see if people use the data. If they do, add more measuring

points. A good way to kill an OBR process is to ignore failure reports and collected data.

For the motor example, the data collected by an operator could be: Temp (inboard & center) /

Vibration Pen (inboard, outboard in horizontal plane) / Current.

5


Our Condition Monitoring Standards (CMS) is a collection of 100 standards for OBR and

maintenance inspections. You can find them as books or they are available as PDF’s for plant / corporate licenses.

Deal with the Resource Issue up Front

Before you launch any OBR process, you must be aware of what is going to happen to resources

and cost. The OBR process will save money increase production output (through reliable

equipment) and reduce the workload long term, but short term; it may do the opposite, why?

If X number of operators are sent out to do detailed inspections, they will find problems. The

whole idea of OBR is to find problems, then prioritize the repairs (hopefully through a work

order system) for the found problems (just like any maintenance jobs), plan them, schedule them,

and then execute them. So through logical reasoning, the backlog of maintenance work will

increase once OBR is started since we find more problems than we did before and it will cost

money to execute that backlog. Once the backlog is worked on, reliability starts to improve for

your equipment (assuming you prioritized correctly). Once the reliability starts to improve, costs

will go down since the plant will have less repairs, use less parts, and have fewer interruptions in

the production schedule.

Plant management and corporate management must understand the basics of any condition

monitoring program (This is true for any inspections; PM, OBR, Vibration, IR, Ultrasonic,

Electrical inspections, Instrumentation loop checks, etc)

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6


Figure. Cost and production throughput numbers from a plant in New Zealand for one of IDCON’s clients. Note

the cost increase early in the project. Also note the 35% reduction in maintenance cost and the 40% increase in

production after implementing operator basic care together with other reliability basics such as planning and

scheduling and root cause analysis. No major capital investment was used to achieve these results.

Most Operators don’t Know how to Inspect Equipment

Detailed inspections require the right type of person, with the right mindset, attitude, and

training. Most mills/ mines/ plants have some type of inspection program, but unfortunately the

inspections are often ineffective.

There may be many reasons why inspections often aren’t effective. But, one reason is that

inspections are not done detailed enough to find problems. Many inspectors simply walk by

equipment, making sure it wasn’t stolen last night, and if they are in a good mood, they may

make sure it hums.

To achieve an effective OBR system, you have to train your operators, both theoretically and

practically. The heart of a good OBR system is that operators understand equipment.

Let’s look at a few examples where deficiencies in inspection and component knowledge can

show up:

Example 1: A typical pump, motor coupling configuration in a paper mill.

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

F96 F97 F98 F99 F00 F01 F02 F03

Production Throughput (no capital investment) Vs. Cost – Plant in New Zealand

Production Throughput

Maintenance Costs

<.*$%D-1'(%

Time

7


This plant has an inspection

system in place, which means

Mr/ Mrs. X should have

checked it. I watched this

piece of equipment

intermittently for a whole week

and it looked pretty much the

same. Some questions would

immediately come up when an

experienced inspector look at

this equipment.

An experienced inspector would see:

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Example 2: A jacking bolt (push bolt) on a motor in a refinery

This is a close up of a jacking bolt on a motor

base. What would an experienced inspector

see? This photo was taken in the Southern USA

in March.

An experienced inspector would see:

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In the picture you see a typical solenoid valve on a

hydraulic system. An inexperienced inspector may just

look at it and confirm the valve is mounted and that the

electrical cable is undamaged.

An experienced inspector would:

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Example 4: Pneumatic Regulator in a surface mine

The picture illustrates a pneumatic regulator that has been in the

game for a while. Most inspectors would not look at the

instrument at all since mechanics feels it belongs to

instrumentation while instrumentation techs seldom do physical

checks of devices.

An experienced mechanic would put his/ her hand in front of

the weep hole and check if air is leaking out of the weep hole. If

he/ she would fee air, he/ she would know the membrane inside

the unit is broken

Leadership and Inspections

These four simple examples are just to illustrate that there is a

difference between walking by equipment and actually

understand how to inspect it. As leaders in operations and maintenance we shouldn’t just give

people a list of 40 equipment numbers and assume they know and are willing to inspect

equipment right.

9


Do your Mill/ Plant/ Mine need help with implementation and training in Operator Based Reliability or Preventive Maintenance. IDCON can help with:

• Advice • Customized training for your equipment • Classroom and hands-on training in how to set up a cost effective PM or OBR

system • Classroom and hands-on training in how to inspect equipment. • Implementation help in creating an implementation plan • Implementation help in setting up Key Performance Indicators (KPI’s) • Coach supervisors in how to manage an OBR and PM system • Train the trainers • IDCON books (click) are available


http://www.idcon.com/maintenance-books.htm

Appendix 1

Appendix 1 – Example Inspection Route

Appendix 1

Example Inspection Route

Notice the CMS reference to the left of the sheet. If the operator (or mechanic) doesn’t know how

to execute the inspection, they can refer to a CMS document that tells them WHAT and perhaps

more importantly WHY to do the inspection.

The inspection text is a standard instruction for a V-belt drive.

Appendix 2

Appendix 2 – Example CMS (V-Belt Drive)

Appendix 2

Example CMS (V-Belt Drive)

IDCON have a little over 100 CMS documents and the library keeps growing as we work more in

different types of industries. The CMS can be purchased on our web site, or by calling us in an

electronic site or corporate license. Some example of companied that use the electronic licenses are:

• International Paper

• Subaru

• Bp

• Tesoro Refining

• Syncrude

• Veyance

• Kimberly Clark

• Whirlpool

• Tarkett

• Swedish Steel

• Stora Enso

• Thilmany

• Norbord

• Meadwestvaco

• And many more.

www.idcon.com © IDCON, INC. 2006 CMS 107R Page 1 of 4

919-847-8764 Do Not Copy

V-Belt Drive CMS107R Condition Monitoring Standards

Basic Principle

A V-belt drive consists of two sheaves and a belt that usually are made of rubber material. The drive

uses friction force between the sheave and the belt to transfer the rotation from one sheave to the

other.


919-847-8764 Do Not Copy

KEY WHAT WHY G

en

era

l C

on

dit

ion

Check the drive for general condition, making sure the belts are

running without flutter and that the drive sheaves appear to be

aligned.

The sheaves sometimes move on the shaft, inspect sheave mounting

with stroboscope for loose attachment bolts or signs of moving

sheave hub. Check that there is no oil or grease dripping onto the

belts. Dust or other fine material that continually are falling onto

the belts can also affect belt performance.

Oil or grease in contact with

the belt will soften the rubber

and allow the belt cover to

wear rapidly. Oil also causes

the belt to slip, which

reduces the performance of

the drive and increases wear.

Foreign material lodged

between the belt and the

sheave wall can wear away

the belt covering and cause

slipping a well.

No

ise a

nd

Vib

rati

on

Belt squeak is an indication of a slipping belt, which may be due to

foreign material between the belt and the sheave or, more

commonly, overload conditions.

Check the belt tension at first opportunity. If belt is too loose, it can

be due to that the sheaves, shaft, motor or driven end has moved, or

that the belt has stretched. Change the belt if you think it is due to

belt stretch (should be seen on belt condition). A belt that once was

tight and then has become loose is a sign of wear. The belt can be

tightened as a “quick fix” if shutdown time is limited, but the belt

will soon become loose again since the wear process is developed at

this point. If you think a component has moved make an effort to

find out the root cause to the problem.

If belt squeal is due to overload condition, try to find the root cause

of the overload condition. Remember that bearings probably are

overloaded at this point. A double load on bearings will reduce

bearing life 8 times.

Belt manufacturers do not recommend the use of belt dressing

If the belt is too loose, the

friction created due to

slipping can burn the belt

fabric. Overload will

decrease belt life and bearing

life considerably.


919-847-8764 Do Not Copy

KEY WHAT WHY S

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elt

Po

sit

ion

Sheave grooves must be smooth, uniform in size, with straight

sidewalls. Dished sidewalls wear out the bottom corners of the belt

and allow the belt to ride lower in the groove. V-belts should ride in

the groove with the top of the belt just above the sheave. Belts

riding at different height indicate either a badly worn belt or worn

sheave grooves. If the belt guard permits, use a strobe to check

condition of belts. Check the belts for uneven wear on the sides,

cracks or tears in the outer covering. Also look for signs of wear on

the bottom of the belt.

If guard permits, check to see if belt has been making contact with

bottom of sheave

Worn belts or sheaves will

not transfer the drive’s

power efficiently and could

cause operating problems.

A shiny surface on the

bottom of the sheave would

indicate either belt or sheave

wear.

Check for shiny

groove bottoms


919-847-8764 Do Not Copy

KEY WHAT WHY S

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On the run inspections are usually more cost effective than

shutdown inspections, since downtime in most plants are costly.

Below are some examples that can enhance and enable on-the-run

inspections.

• Belt guard needs to be a “see-through” type, for example wire

mesh.

• Strike a line across belt when they are installed in order to see

if one or more belts are slipping.

• For critical equipment, use the hydraulic motors shelf that

continuously regulates the belt tension, and speeds up belt

changes.

Modify guards in order to

see sheaves, and belt with a

stroboscope. Make the “see-

through” guards a plant

standard and implement

necessary systems in

purchasing/ engineering.

Enables quick inspection by

looking on top of the belts.

To prolong belt life.

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