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Practical Machinery Management for Process Plants

VOLUME d THIRD EDITION

Improving Machinery

Practical Machinery Management for Process Plants:

Volume 1: Improving Machinery Reliability, 3rd edition

Volume 2: Machinery Failure Analysis and Troubleshooting, 3rd edition

Volume 3: Machinery Component Maintenance and Repair, 2nd edition

Volume 4: Major Process Equipment Maintenance and Repair, 2nd edition

Other Machinery Engineering Texts from the Same Author:

Introduction to Machinery Reliability Assessment, 2nd edition

Reciprocating Compressors: Operation and Maintenance

I Practical Machinery Management for Process Plants I

Improving Machinery Reliability

Heinz P. Bloch

Gulf Professional Publishing is an imprint of Elsevier Science

Copyright 0 1982, 1988, 1998 by Elsevier Science (USA). All rights

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Library of Congress Cataloging-in-Publication Data

Bloch, Heinz P., 1933-

Improving machinery reliability / Heinz P. Bloch. - 3‘d ed.

Includes bibliographical references and index.

p. cm. -(Practical machinery management for process plants; v. 1)

ISBN 0-88415-661-3 (alk. paper)

1. Machinery-Reliability. I. Title. II. Series: Bloch, He& P., 1933-

Practical machinery management for process plants. 31d ed. ; v. 1.

TJ153.B58 1998

621.8’1-dc21 98-26184

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Printed in the United States of America.

Contents

Preface .......................................... x

Introduction ...................................... xx

1 Requirements Specification ..................... 1

Industry Standards Available for Major Machinery in Process Plants, 1;

How to Deal with the Typical API Data Sheet, 2; Narrative

Specifications Lead to Better Machinery, 15; Considering Uprateability

and Low Failure Risk, 21; Auxiliary Systems for Turbomachinery: The

Systematic Approach, 24; Dealing with Deviations from the

Specification, 34; Specifying Machinery Documentation Requirements,

37; Conclusion, 5 1

2 Vendor Selection and Bid Conditioning ............ 53

Selecting Major Machinery Vendors, 53; Applying and Reviewing

Machinery Reliability Improvements Derived from Modern

Electronics, 54; Selecting a Pump Vendor, 64; Bid Tabulation and Bid

Conditioning: An Overview, 76; Reference, 8 1

Audits Versus Reviews, 82; Where to Concentrate Audit and Review

Efforts, 82; Rotordynamic Design Audits, 83; Auditing and Reviewing

Centrifugal Compressors, 125; Auditing and Reviewing Steam Turbines,

135; Evaluating Major Reciprocating Compressors, 139; Reliability

Review for Centrifugal Pumps, 146; Significant Differences in Bearings

and Bearing Housings, 156; Marginal Lubrication: A Factor in Pump

Failures, 160; Applying Roller Bearings in Centrifugal Pumps, 168; How

Much Oil Is Enough?, 171; Bearing Selection Can Make a Difference,

172; Air Cooling Provisions for Bearing Housing-How Good? 173;

Stuffing Box Cooling Is Not Usually Effective, 174; Pumps for Handling

Entrained Gases, 176; Selection Criteria for Zero Emission Pumps, 178;

Design Appraisals for Special-Purpose Gearing, 18 1; Evaluating Cooling

Tower Fans and Their Drive Systems, 200; Reliability Reviews in Uprate

Situations, 203; Reliable Shaft-Hub Connections for Turbomachinery

Couplings, 213; How to Keep Track of Reliability Review Tasks, 224;

Machinery Reliability Audits for Existing Plants, 224; References, 238

3 Machinery Reliability Audits and Reviews .......... 82

V

4 Maintenance and Benchmarking Reliability . . . . . . . . 242

Maintenance Measurement, 242; Organize to Manage Reliability, 249;

Maintenance Cost vs. Replacement Asset Value: Another Maintenance

Spending Benchmark, 257

5 Life Cycle Cost Studies . . . . . . . . . . . . . , . . . . . . . . . . .259

Simplified Life Cycle Cost Estimating, 259; Life Cycle Cost

Assessment: The Rigorous Method, 272; Summary, 3 10;

References, 3 10

6 Extending Motor Life in the Process

Plant Environment . , . . . . . . . . . . . . . . . , . . . . . . . . . . ,313

Squirrel-cage Motors Are Most Prevalent, 3 14; Motor Insulation

Systems, 3 14; Insulation Classification, 3 15; Ambient Plus, 3 15; A

Bank of Motor Life, 3 17; Running Cooler-A Relative Term, 3 18;

Thermal Cushion, 3 19; Enclosures, 3 19; Standard, but Different, 3 19;

Learning from Failures, 320; More about Thermal Loading, 320;

Economics of Oversizing, 321; Keep Bearings in Mind, 323; Motor

Mounting Basics, 325; Motor System Tuneup, 326; Pumping and

Piping, 326; Power Points, 326; Over-Current Insurance, 327; Motor

Life Insurance Terms, 328; Notes, 328

7 Equipment Reliability Improvement through

Reduced Pipestress . . . . . . . , . . . , . . . . . , m.. . . . . . ,329

Allowable Load, 33 1 ; Excessive Flexibility, 333; Theoretical

Restraints, 334; Expansion Joints, 335; Other Practical Considerations,

337; References, 338

8 Startup Responsibilities . . . . . m.. . . . . . . . . . . . . . . . . .339

Summary of Startup Preparations for Process Plant Machinery, 339;

Machinery Startup Review Tasks, 342; Machinery Startup Reporting

Structure, 344; Documentation for Effective Tracking of Progress, 348;

Vendor Assistance and Outside Facilities, 359; Consultants and

Contract Assistance. 359

9 Spare Parts and Their Effect on Service Factors . . . . 361

Spare Parts Philosophies, 361; Spare Parts Storage and Retrieval, 361 ;

Spare Parts Documentation, 363

10 Maintenance for Continued Reliability . . . . . , . . . . . . . 365

Modern Maintenance Approaches and when to Apply Them, 365;

Maintenance Management Options, 374; Detailed Task Descriptions

vi

Improve Maintenance Effectiveness, 380; Machinery Turnaround

Planning, 394; Turnaround Scope Development through Reliability,

Availability, and Maintainability Analysis, 401 ; Effective Maintenance:

Preventive or Predictive?, 41 6; Preventive Versus Predictive

Maintenance for Typical Centrifugal Pumps, 421; How to Be a Better

Maintenance Engineer, 429; The Role of the Maintenance Engineer in

the Knowledge Age, 43 I; References, 432

11 Maintenance Cost Reduction ................... .434

Eliminating Cooling Water from General-Purpose Pumps and Drivers,

434; Economics of Dry-Sump Oil-Mist Lubrication for Anti-friction

Bearings, 440; Gear Couplings Versus Non-lubricated Couplings, 45 1 ;

Elastomeric Couplings, 457; Quantifying the Reliability Impact of

Laser Alignment Techniques, 461 ; Quantifying Impact, 470; Why and

How to Monitor Centrifugal Pump Condition, 477; References, 483

12 Lubrication and Reliability ...................... .485

Methods and Criteria for Lube-Oil Purification, 485; Cost Justification

and Latest Technology for the On-Stream Purification of

Turbomachinery Lube Oil, 49 1 ; Synthetic Lubricants and Reliability

Improvement, 503; Vibration Performance Improved with Synthetics,

5 15; Automatic Grease Lubrication as a Reliability Improvement

Strategy, 517; References, 525

13 Providing Safety and Reliability through Modern

Sealing Technology ............................ ,527

API Standard 682,528; Low-Emission Single Seal Design, 531; Dual

Seal Arrangements, 543; Compact Gas Seal Technology for Pumps,

550; The Reliability Impact of Special Seals for Non-Pump

Applications, 558; Specialty Seals for Non-Pump Applications, 565;

Dry Gas Compressor Seals, 58 1; Warding off Equipment Reliability

Setbacks: A Postscript, 593; References, 598

AppendixA ...................................... 600

Useful and Interesting Statistics

AppendixH ..................................... .609

Common Sense Reliability Models

Index ............................................ 668

vii

Most of today’s process plants proudly display a Company Vision

statement. Sadly, relatively few pursue the kinds of action needed to

reach their often lofty visions. Conversely, it should be clear to us that a

serious company will take steps today to identify and implement the sci￾ence and technology “investments” necessary for modern petrochemical

plants to remain competitive into the next decade and beyond.

Based on my observation or perception of trends among the trendset￾ters and the forward thinking of the “Best-of-Class” companies, I would

like to alert the reader to a few of the work processes, organizational

realities, lineups or interfaces, as well as hardware and software systems

that have been implemented by the most profitable process plants in my

career, dating from the 1960s to the present.

I will summarize by giving a few important explanations. First, none

of the items I highlighted in this third edition were concocted for the

sake of compiling a wish list of far-fetched goals. Every one of the vari￾ous observations and recommendations either reflects current practice or

has been implemented by one or more plants in the United States or

overseas.

Second, no single plant presently applies or implements all the recom￾mendations or practices given here. It is nevertheless of real importance

to acknowledge that some companies come surprisingly close to practic￾ing these reliability concepts or will soon implement them. The future

belongs to them.

Third, it may not be realistic to expect every company to have the

same priorities for implementing what is perceived to be the ideal path

toward high reliability and profitability. However, it would be equally

unrealistic to assume that a company can pick and choose from a smor￾gasbord of easy items and forget about the politically difficult ones. Mea￾suring up to tough competition will require an uncompromising and sin￾gle-minded desire to pursue excellence. Paying lip service to reliability

and profitability concepts without implementing the difficult and some￾times unpopular steps necessary to get there is a costly exercise in futility

and is doomed to failure.

viii

Finally, we should a11 recognize the interwoven relationship of so

many of the requirements and issues. It is important to realize that we

can logically hold someone accountable for quality and solid perfor￾mance only after training that person. Progress implies change. Change

implies risk and extra effort to manage the risk. We can better justify,

specify, purchase, install, operate, and maintain process plant machinery

only if we invest time and money up front in reading and learning about

best available practices. That, of course, is what this book is all about.

Many of my colleagues in process plants, machinery manufacturing

facilities, or in the consulting field are practitioners of the various relia￾bility improvement or assurance approaches. And for allowing me to

include some of their work in this revised and updated text, sincere

thanks go to Paul Barringer, whose work on life cycle costing and relia￾bility assessment is truly unique; Lou Bewig for some excellent work on

benchmarking; Gary Bostick (Woodward Governor) for a concise write￾up on modern turbomachinery controls; R. Ellis and M. Galley (Dow)

for documenting task descriptions used in best-of-class maintenance;

Galen Evans (Ludeca) for quantifying the reliability impact of laser￾optic alignment issues; s. Gupta and John Paisie (Sun Oil Company) for

groundbreaking work on the value-related definition of turnaround

scope; Bill Key (Flowserve), W. Schoepplein, and J. Nasowicz (Dich￾tungswerke Feodor Burgmann), Bill Adams, W. Binning, and R. Phillips

(Flowserve), Jim Netzel and P. Shah (John Crane) all of whom con￾tributed lucid material on modern sealing technology; John s. Mitchell

for his always authoritative and equally compelling summary of the

direction in which maintenance efforts must be channelled in the twen￾ty-first century; L. C. Peng for his contribution on pipe stress issues;

Jean Revelt (Lincoln Electric) for neatly explaining important reliability

aspects of electric motors; R. Ricketts (Solomon Associates) for shed￾ding considerable light on rigorous benchmarking; and to Paul Smith for

his observations on the “knowledge worker” who is certain to be needed

to deal with reliability issues from this day on.

Their contributions and those of others whose personal and/or compa￾ny names are mentioned in footnotes and captions are gratefully

acknowledged.

Heinz P Bloch, I? E.

ix

Introduction

The View of an Advocate for Change*

Machinery reliability management in the process industries can be

divided into three phases: equipment selection and pre-erection reliability

assurance, preparation for effective startup, and post-startup reliability

assurance and maintenance cost reduction. All of these phases are impor￾tant; they are intertwined and merit equal attention. The techniques and

procedures described in this text cover essential elements of each phase;

they have been critically examined and have led to substantially

improved reliability and maintenance efficiencies. Adoption of applica￾ble techniques and procedures at your plant is certain to result in similar

benefits.

In the quest for increased reliability, multiple dimensions must be con￾sidered.

The first is whether maximum profitability for a given enterprise and

maximum reliability are one and the same. Recent interviews with expe￾rienced individuals indicate a growing awareness that business-operating

and profit models often change dramatically with time and other factors.

The latter include status of product sales (sold out or not sold out), level

of inventory, alternative sources, and facility design life. The funds nec￾essary to maintain and improve reliability must fit profitably within the

enterprise business model.

Next are the methods and practices that must be established and main￾tained to assure optimum reliability. Good design and installation prac￾tices, improved components and materials, condition-directed mainte￾nance, root cause identification and correction are the subjects dealt with

in this book. All are vital and must be addressed. Success demands more

than awareness. Acceptance and top-down commitment to optimizing

reliability are mandatory.

*Contributed by John S. Mitchell, San Juan Capistrano, California. Adapted by permission.

X

Organizational and administrative aspects of every function must be

streamlined and optimized. In the reliability area this means bringing

maintenance and operations closer together in a supportive partner rela￾tionship rather than the common adversarial hierarchical organization.

Finally, information creation and effective communications are essen￾tial to measure performance, assure conformance to enterprise objectives

and best-of-class benchmarks. Within a typical enterprise there are at

least four classifications of information. Senior executives require infor￾mation such as costs-per-unit output and production availability. At the

MRP (manufacturing resource planning) level, long-term prediction of

equipment lifetime-the ability to meet contractual obligations-is

essential. Operations must have detailed, real-time knowledge of equip￾ment condition and any immediate threats to production. At the detail

level, condition assessment, maintenance management, and information

systems must function together. Tasks include gathering and managing

data, creating and exchanging information as well as directing appropri￾ate information to other levels in the organization. Accomplishing this

ambitious, crucial objective requires generically open systems and a

common method of communications.

In many industrial enterprises, senior management appears to be grow￾ing increasingly aware that maintenance and reliability improvement, or

more broadly, lifetime asset management, is the “final frontier” of maxi￾mizing profitability. Thus far, most of the focus seems to be on reducing

costs by re-engineering the administrative process and eliminating per￾sonnel. Requirements for real SUCC~SS include awareness that mainte￾nance and reliability improvement are strategic contributors to income

and profitability. Investment to optimize reliability and reduce the need

for maintenance is imperative. From a strategic perspective, maintenance

cost reduction is a result-not an action.

Optimized practices such as pre-procurement equipment reliability

audits, installation reviews, and condition-directed or predictive mainte￾nance have been in use since the 1960s. All have proven highly effective

toward improving availability and reducing unexpected failures and

costs. Unfortunately, results have not been communicated effectively in

financial terms to senior management. As a consequence, many SUCCCSS￾ful condition-directed maintenance programs are being curtailed or, in

some cases, terminated altogether as cost cutting measures.

Are arbitrary cost reductions and changes for change sake the way to

greater maintenance efficiency? In most cases the answer is no. Arbitrary

xi

downsizing, eliminating proven programs such as condition-directed

maintenance to end the ongoing operating cost may well have the oppo￾site effect-reduced availability, reduced efficiency, and increased main￾tenance costs.

The answers are in three areas: value, organization, and information.

These issues are addressed in the text.

Reliability improvement and maintenance activities must be reoriented

from a cost-centered to a value- or profit-centered mentality. Within a

cost-centered framework there are no incentives for improvement. In fact,

there are disincentives for improvement! Everyone knows what happens if

a maintenance budget is underspent and how those responsible for the

achievement are rewarded. “Spend it or lose it” is known to all. As a

result, many expenditures occur at year end-some unwise-to make cer￾tain budgeted funds are all spent. It would be far better to shift to a value

orientation that encourages continuous improvement and rewards

increased effectiveness.

Many leading enterprises are shifting to multi-functional team-based

organizations. Benefits include single-person accountability for a readily

identifiable process or area, pride of ownership, and elimination of coun￾terproductive trade mindsets.

Success with the necessary changes requires enabling technology.

Technology includes designing in reliability, designing out maintenance,

and implementation of productivity-improving information systems that

make the remaining maintenance tasks easier and more efficient. Plan￾ning, scheduling, tracking workflow, and providing time, materials, and

cost information are vital functions of computerized management and

information systems. Technology is indispensable for condition assess￾ment and for clearly conveying equipment status to operators, mainte￾nance, and production planners. Technology also plays a vital role in

assembling and communicating planning and performance information,

value and benefits to senior executives and financial managers.

There must be an overall vision or concept that unifies individual

changes into an optimized whole fabric. Profit-centered maintenance, the

first stage in the unification process, establishes value as the prime objec￾tive. Value is achieved by maximizing quality, efficiency, and commer￾cial availability while permanently reducing the need for maintenance.

Add an optimized organization and crucial information made available at

every level of the organization and the result is value-driven asset man￾xii