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Industrial Machinery Repair: Best Maintenance Practices Pocket Guide... Industrial machinery repair : best maintenance practices pocket guide / Ricky Smith and Keith Mobley.. Maintenance

Industrial Machinery Repair: Best Maintenance Practices Pocket Guide

Amsterdam Boston London New York Oxford Paris San Diego

San Francisco Singapore Sydney Tokyo

Butterworth–Heinemann is an imprint of Elsevier Science.

Copyright © 2003, Elsevier Science (USA) All rights reserved.

No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher.

Recognizing the importance of preserving what has been written, Elsevier-Science prints its books on acid-free paper whenever possible.

Library of Congress Cataloging-in-Publication Data

Smith, Ricky.

Industrial machinery repair : best maintenance practices pocket guide / Ricky Smith and Keith Mobley.

p cm.

ISBN 0-7506-7621-3 (pbk : alk paper)

1 Machinery–Maintenance and repair 2 Industrial equipment–Maintenance and repair.

I Mobley, Keith II Title.

TJ153.S6355 2003

621.8
16–dc21

2003040435

British Library Cataloguing-in-Publication Data

A catalogue record for this book is available from the British Library.

The publisher offers special discounts on bulk orders of this book.

For information, please contact:

Elsevier Science

Manager of Special Sales

200 Wheeler Road, 6th Floor

Chapter 1 Introduction: Why Use Best Maintenance

Repair Practices? 1Chapter 2 Fundamental Requirements of Effective

Preventive/Predictive Maintenance 10Chapter 3 Maintenance Skills Assessment 26Chapter 4 Safety First, Safety Always 50Chapter 5 Rotor Balancing 57

Chapter 7 Chain Drives 120Chapter 8 Compressors 133Chapter 9 Control Valves 180Chapter 10 Conveyors 203Chapter 11 Couplings 215Chapter 12 Dust Collectors 245Chapter 13 Fans, Blowers, and Fluidizers 261Chapter 14 Gears and Gearboxes 283Chapter 15 Hydraulics 314Chapter 16 Lubrication 327Chapter 17 Machinery Installation 348Chapter 18 Mixers and Agitators 353Chapter 19 Packing and Seals 361

Ricky Smith wants to offer his thanks to the following individuals whocontributed to the writing of this book Bruce Hawkins, Life Cycle Engi-neering; Darryl Meyers, former U.S Army Warrant Officer; Steve Lindborg,Chemical Lime Company; Robby Smith (his brother), International PaperCorporation; and J.E Hinkel, Lincoln Electric Company Ricky also wants

to thank Life Cycle Engineering, where he is currently employed, forthe opportunity to write this book; Alumax–Mt Holly—currently Alcoa–

Mt Holly—where he worked as a maintenance technician, for all the trainingand the chance to expand his knowledge; and Dr John Williams, who alwaysbelieved in him

Industrial Machinery Repair: Best Maintenance Practices Pocket Guide

Amsterdam Boston London New York Oxford Paris San Diego

San Francisco Singapore Sydney Tokyo

Butterworth–Heinemann is an imprint of Elsevier Science.

Copyright © 2003, Elsevier Science (USA) All rights reserved.

No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher.

Recognizing the importance of preserving what has been written, Elsevier-Science prints its books on acid-free paper whenever possible.

Library of Congress Cataloging-in-Publication Data

Smith, Ricky.

Industrial machinery repair : best maintenance practices pocket guide / Ricky Smith and Keith Mobley.

p cm.

ISBN 0-7506-7621-3 (pbk : alk paper)

1 Machinery–Maintenance and repair 2 Industrial equipment–Maintenance and repair.

I Mobley, Keith II Title.

TJ153.S6355 2003

621.8
16–dc21

2003040435

British Library Cataloguing-in-Publication Data

A catalogue record for this book is available from the British Library.

The publisher offers special discounts on bulk orders of this book.

For information, please contact:

Elsevier Science

Manager of Special Sales

200 Wheeler Road, 6th Floor

Chapter 1 Introduction: Why Use Best Maintenance

Repair Practices? 1Chapter 2 Fundamental Requirements of Effective

Preventive/Predictive Maintenance 10Chapter 3 Maintenance Skills Assessment 26Chapter 4 Safety First, Safety Always 50Chapter 5 Rotor Balancing 57

Chapter 7 Chain Drives 120Chapter 8 Compressors 133Chapter 9 Control Valves 180Chapter 10 Conveyors 203Chapter 11 Couplings 215Chapter 12 Dust Collectors 245Chapter 13 Fans, Blowers, and Fluidizers 261Chapter 14 Gears and Gearboxes 283Chapter 15 Hydraulics 314Chapter 16 Lubrication 327Chapter 17 Machinery Installation 348Chapter 18 Mixers and Agitators 353Chapter 19 Packing and Seals 361

Ricky Smith wants to offer his thanks to the following individuals whocontributed to the writing of this book Bruce Hawkins, Life Cycle Engi-neering; Darryl Meyers, former U.S Army Warrant Officer; Steve Lindborg,Chemical Lime Company; Robby Smith (his brother), International PaperCorporation; and J.E Hinkel, Lincoln Electric Company Ricky also wants

to thank Life Cycle Engineering, where he is currently employed, forthe opportunity to write this book; Alumax–Mt Holly—currently Alcoa–

Mt Holly—where he worked as a maintenance technician, for all the trainingand the chance to expand his knowledge; and Dr John Williams, who alwaysbelieved in him

1 Introduction: Why Use Best

Maintenance Repair Practices?

“Only Permanent Repairs Made Here”

This book addresses, in a simplistic manner, the proper principles andtechniques in “Best Maintenance Practices—Mechanical.”

If these principles and techniques are followed, they will result in a seriousreduction in “self-induced failures.” This book is a tool that should be carriedand referenced by all mechanical maintenance personnel

A number of surveys conducted in industries throughout the United States have found that 70% of equipment failures are self-induced.

Maintenance personnel who are not following what are termed “BestMaintenance Repair Practices” substantially affect these failures Between30% and 50% of the self-induced failures are the result of maintenancepersonnel not knowing the basics of maintenance Maintenance personnelwho, although skilled, choose not to follow best maintenance repair prac-tices potentially cause another 20% to 30% of those failures The existence

of this problem has been further validated through the skills assessmentprocess performed in companies throughout the state of Georgia This pro-gram evaluated the knowledge of basic maintenance fundamentals through

a combination of written, identification, and performance assessments ofthousands of maintenance personnel from a wide variety of industries.The results indicated that over 90% lacked complete basic fundamentals

of mechanical maintenance This book focuses on the “Best MaintenanceRepair Practices” necessary for maintenance personnel to keep equip-ment operating at peak reliability and companies functioning more prof-itably through reduced maintenance costs and increased productivity andcapacity

The potential cost savings can often be beyond the understanding or prehension of management Many managers are in a denial state regardingmaintenance The result is that they do not believe that repair practicesdirectly impact an organization’s bottom line or profitability

com-2 Introduction: Why Use Best Maintenance Repair Practices?

More enlightened companies have demonstrated that, by reducing induced failures, they can increase production capacity by as much

self-as 20%.

Other managers accept lower reliability standards from maintenance effortsbecause they either do not understand the problem or they choose to ignorethis issue A good manager must be willing to admit to a maintenanceproblem and actively pursue a solution

You may be asking, what are the “Best Maintenance Repair Practices”? Here are a few that maintenance personnel must know (See Table 1.1.) Looking through this abbreviated Best Maintenance Repair Practices table, try to determine whether your company follows these guidelines.

The results will very likely surprise you You may find that the best practiceshave not been followed in your organization for a long time In order to fixthe problem you must understand that the culture of the organization is atthe bottom of the situation Everyone may claim to be a maintenance expertbut the conditions within a plant generally cannot often validate that this

is true In order to change the organization’s basic beliefs, the reasons why

an organization does not follow these best practices in the repair of theirequipment must be identified

“Only Permanent Repairs Made Here”

A few of the most common reasons that a plant does not follow best maintenance repair practices are:

1 Maintenance is totally reactive and does not follow the definition ofmaintenance, which is to protect, preserve, and prevent from decline(reactive plant culture)

2 Maintenance personnel do not have the requisite skills

3 The maintenance workforce lacks either the discipline or direction tofollow best maintenance repair practices

4 Management is not supportive, and/or does not understand the sequences of not following the best practices (real understandingmust involve a knowledge of how much money is lost to the bottomline)

con-Table 1.1 Best maintenance repair practices

Probability of future failures—number Consequences of self-induced fail- Maintenance Required best for not following ures vs following

2 Clean end of grease gun.

3 Lubricate with proper amount and right type of lubricant.

4 Lubricate within variance

Align motor couplings

utilizing dial indicator or

Premature coupling failure.

Premature bearing and seal failure in motor and driven unit.

Excessive energy loss.

100%
7 vs 1

V-Belts Measure the tension of

V-belts through tension

and deflection utilizing a

belt tension gauge.

1 Identify the proper tension and deflection for the belt.

2 Set tension to specifications.

Premature belt failures through rapid belt wear or total belt failure Premature bearing failure

of driven and driver unit Belt creeping or slipping causing speed variation without excessive noise.

Motor shaft breakage.

100%
20 vs 1

Continued

Table 1.1 continued

Probability of future failures—number Consequences of self-induced fail- Maintenance Required best for not following ures vs following

Hydraulic

Components

Hydraulic fluid must be conditioned to component specifications.

1 Hydraulic fluid must be input into the hydraulic reservoir utilizing a filter pumping system only.

2 Filters must be rated to meet the needs of the component reliability and not equipment

manufacturer’s specification.

3 Filters must be changed

on a timed basis based on filter condition.

4 Oil samples must be taken

on a set frequency, and all particles should be trended in order to understand the condition and wear of the hydraulic

Sticking hydraulic Premature or unknown hydraulic pump life.

Sustaining hydraulic competency

by maintenance personnel.

Length of equipment breakdown causes lost production.

100%
30 vs 1

Introduction: Why Use Best Maintenance Repair Practices? 5

Keep Preserve Protect

MAINTAIN

MAINTENANCE

The act of MAINTAINING.

KEEP in an existing state.

PRESERVE from failure or decline.

“The Maintenance Cost Iceberg.”)

Second, identify the source of the problem (this could be combination ofissues):

● Maintenance skill level: Perform skills assessment (written and mance based) to evaluate whether skill levels are adequate to meet “BestMaintenance Repair Practices” for your specific maintenance organization

perfor-● Maintenance culture: Provide training to all maintenance and ment relative to a change in maintenance strategy and how it will impactthem individually (e.g., increase in profit for the plant, less overtime

manage-6 Introduction: Why Use Best Maintenance Repair Practices?

Direct Maintenance Costs Indirect Maintenance Costs

Maintenance Budget

Operating Budget

Materials Overtime

Labor Contract Services

Overhead & Benefits

Complaints

Environment

Crisis Management

Lost Business Emergency Purchases

Product Liability

Fines

Waste

Disposal

Figure 1.2 The maintenance cost iceberg

resulting from fewer equipment breakdowns, etc.) Track and measurethe changes and display the results to everyone

● Maintenance strategy: Develop a plan to introduce a proactive tenance model with “Preventive and Planned Maintenance” at the top

main-of planned priorities This will provide more time for performingmaintenance utilizing the “Best Maintenance Repair Practices.”

Third, implement the changes needed to move toward following “BestMaintenance Repair Practices” and measure the financial gains

Everyone should be aware that financial rewards can be great but we must understand why they can also be hard to achieve.

Several of the reasons why implementing a program of change, such as theone discussed, can be doomed to failure include:

● Management not committed;

● Lack of discipline and direction;

Introduction: Why Use Best Maintenance Repair Practices? 7

● Lack of management commitment and accountability;

● Momentum becomes slowed or changes direction;

● Lack of an adequately skilled workforce;

● No gap analysis or specific action plan to guide the effort to closethe gaps;

● Conflict between emergencies and performing maintenance following

“Best Maintenance Repair Practices” (this does not mean all “emergent”repairs must be performed to “as built” specifications the first time, but

it does mean that the repair, especially a temporary fix, will be correctedduring the next outage of the equipment)

To conclude, as many as 90% of companies in the United States do not low “Best Maintenance Repair Practices.” The percent that do follow thesepractices are realizing the rewards of a well run, capacity-driven organiza-tion that can successfully compete in today’s and tomorrow’s marketplace.Remember that use of the “Best Maintenance Repair Practices” might justbecome a mandatory requirement for the future success of an organization

fol-in today’s economy

Utilize this book as a resource to:

1 Write corrective maintenance procedures to attach to specific work ordertasks in a computerized maintenance management system (CMMS)

2 Train personnel regarding new and existing maintenance repair dures

proce-3 Be used as a tool by a current maintenance staff Have all maintenancepersonnel use this book on the job site in order to follow “Best Mainte-nance Practices.” (This book can be set up in a storeroom in order to bereplaced as the book is worn and damaged on the job site.)

Preventive and Predictive

Maintenance (PPM)

PPM is more than the regular cleaning, inspection, tightening, lubrication,and other actions intended to keep durable equipment in good operat-ing condition and to avoid failures It is an investment in the future—afuture without major, disruptive breakdowns of critical equipment It is,

8 Introduction: Why Use Best Maintenance Repair Practices?

at times, an investment without an immediate return on that investment.Here the philosophy must be, “Pay me now or pay me later,” because that isexactly what happens when it comes to PPM If preventive maintenance isnot accomplished in the proper way and in a timely manner, then the pay-me-later clause will occur at the most inopportune time That is the premisethat must be established and promoted by management While the mainte-nance department has the day-to-day responsibility of plant PPM, the plantmanager is ultimately responsible for setting the expectations concerningplant preventive maintenance

In general, the preventive and predictive maintenance effort is not focused

To spotlight some of the weaknesses, review the following points:

1 Many of the components that make up a good predictive maintenanceprogram have not been developed;

1 No mobile equipment has written PMs

2 Logbooks are used, but it can’t be determined who was looking at andusing the data

3 All preventive maintenance regarding lubrication should be reviewedfor detail and accuracy

4 The forecasting and generation of PM tasks because of the state of theCMMS is not part of the normal maintenance routine

Recommendations

Review all lubrication-related task procedures for detail and content

● Provide training in effective plant lubrication procedures and techniques.The lubricator, maintenance personnel, and maintenance supervisorsshould attend