Machinery Component Maintenance and Repair ppt

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Practical Machinery Management for Process Plants
Volume 3, Third Edition
Machinery Component
Maintenance and Repair
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Practical Machinery Management for Process Plants
Volume 3, Third Edition
Machinery Component
Maintenance and Repair
AMSTERDAM
•
BOSTON
•
HEIDELBERG
•
LONDON
•
NEW YORK
OXFORD
•
PARIS

•
SAN DIEGO
•
SAN FRANCISCO
•
SINGAPORE
SYDNEY
•
TOKYO
Gulf Professional Publishing is an imprint of Elsevier
Heinz P. Bloch and
Fred K. Geitner
Gulf Professional Publishing is an imprint of Elsevier
30 Corporate Drive, Suite 400, Burlington, MA 01803, USA
Linacre House, Jordan Hill, Oxford OX2 8DP, UK
Copyright © 2005, Elsevier Inc. 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.
Permissions may be sought directly from Elsevier’s Science & Technology Rights
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You may also complete your request on-line via the Elsevier
homepage (), by selecting “Customer Support” and then “Obtaining
Permissions.”
Recognizing the importance of preserving what has been written, Elsevier prints its books on acid-
free paper whenever possible.
Library of Congress Cataloging-in-Publication Data
Application submitted
British Library Cataloguing-in-Publication Data
A catalogue record for this book is available from the British Library.

ISBN: 0-7506-7726-0
For information on all Gulf Professional Publishing publications visit our Web site at
www.books.elsevier.com
04050607080910987654321
Printed in the United States of America
v
Contents
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii
Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
Part I: Background to Process Machinery Maintenance
Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1 Machinery Maintenance: An Overview . . . . . . . . . . . . . . . . . 3
2 Maintenance Organization and Control for Multi-Plant
Corporations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Type of Operation. Manager’s Role. Maintenance. Central Control System.
Incentives for Computer Systems. Setting Up an Effective System. Machinery
Maintenance on the Plant Level. Assignment of Qualified Personnel. Timing and
Basic Definition of Critical Pre-Turnaround Tasks. Specific Preparation and
Planning. Documenting What You’ve Done.
3 Machinery Foundations and Grouting . . . . . . . . . . . . . . . . . . 61
What’s an Epoxy? Epoxy Grouts. Proper Grout Mixing Is Important. Job
Planning. Conventional Grouting. Methods of Installing Machinery. Pressure-
Injection Regrouting. Prefilled Equipment Baseplates: How to Get a Superior
Equipment Installation for Less Money. Appendix 3-A—Detailed Checklist for
Rotating Equipment: Horizontal Pump Baseplate Checklist. Appendix 3-B—
Specification for Portland Cement Grouting of Rotating Equipment. Appendix
3-C—Detailed Checklist for Rotating Equipment: Baseplate Grouting. Appen-
dix 3-D—Specifications for Epoxy Grouting of Rotating Equipment. Appendix
3-E—Specification and Installation of Pregrouted Pump Baseplates.
v

4 Process Machinery Piping . . . . . . . . . . . . . . . . . . . . . . . . . . 148
Fundamentals of Piping Design Criteria. Piping Design Procedure. The When,
Who, What, and How of Removing Spring Hanger Stops Associated with
Machinery. Flange Jointing Practices. Primary Causes of Flange Leakage. The
Importance of Proper Gasket Selection. Flange Types and Flange Bolt-Up.
Controlled Torque Bolt-Up of Flanged Connections. Recommendations for the
Installation, Fabrication, Testing, and Cleaning of Air, Gas, or Steam Piping.
Pickling Procedure for Reciprocating Compressor Suction Piping: Method I.
Cleaning of Large Compressor Piping: Method II. Appendix 4-A—Detailed
Checklist for Rotating Equipment: Machinery Piping. Appendix 4-B—Specifi-
cations for Cleaning Mechanical Seal Pots and Piping for Centrifugal Pumps.
Appendix 4-C—Detailed Checklist for Rotating Equipment: Pump Piping.
Part II: Alignment and Balancing . . . . . . . . . . . . . . . . . . . . . . . . . 197
5 Machinery Alignment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199
Prealignment Requirements. Choosing an Alignment Measurement Setup.
Checking for Bracket Sag. Face Sag Effect—Examples. Interpretation and Data
Recording. The Graphical Procedure for Reverse Alignment. Thermal Growth—
Twelve Ways to Correct for It. Thermal Growth Estimation by Rules of Thumb.
6 Balancing of Machinery Components . . . . . . . . . . . . . . . . . . . 258
Definition of Terms. Purpose of Balancing. Types of Unbalance. Motions of
Unbalanced Rotors. Balancing Machines. Centrifugal Balancing Machines.
Measurement of Amount and Angle of Unbalance. Classification of Centrifugal
Balancing Machines. Maintenance and Production Balancing Machines. Estab-
lishing a Purchase Specification. Supporting the Rotor in the Balancing
Machine. End-Drive Adapters. Balancing Keyed End-Drive Adapters. Balanc-
ing Arbors. Testing Balancing Machines. Inboard Proving Rotors for Horizontal
Machines. Test Procedures. Balance Tolerances. Special Conditions to Achieve
Quality Grades G1 and G0.4. Balance Errors Due to Rotor Support Elements.
Recommended Margins Between Balance and Inspection Tolerances. Computer-
Aided Balancing. Field Balancing Overview. Field Balancing Examples.

Appendix 6-A—Balancing Terminology. Appendix 6-B—Balancing Machine
Nomenclature. Appendix 6-C—Balancing and Vibration Standards. Appendix 6-
D—Critical Speeds of Solid and Hollow Shafts.
Part III: Maintenance and Repair of Machinery Components . . . . . 367
7 Ball Bearing Maintenance and Replacement . . . . . . . . . . . . . . 369
Engineering and Interchangeability Data. Cleanliness and Working Conditions
in Assembly Area. Removal of Shaft and Bearings from Housing. Cleaning the
vi
Bearing. Shaft and Housing Preparation. Checking Shaft and Housing
Measurements. Basic Mounting Methods. Hints on Mounting Duplex Bearings.
Preloading of Duplex Bearings. Importance of the Correct Amount of Preload.
Assembly of Bearings on Shaft. Cautions to Observe During Assembly of
Bearings into Units. Mounting with Heat. Checking Bearings and Shaft After
Installation. Assembly of Shaft and Bearings into Housing. Testing of Finished
Spindle. Maintain Service Records on All Spindles.
8 Repair and Maintenance of Rotating Equipment
Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447
Pump Repair and Maintenance. Installation of Stuffing Box Packing. Welded
Repairs to Pump Shafts and Other Rotating Equipment Components. How to
Decide if Welded Repairs Are Feasible. Case Histories. High Speed Shaft Repair.
Shaft Straightening. Straightening Carbon Steel Shafts. Casting Salvaging
Methods. OEM vs. Non-OEM Machinery Repairs.
9 Centrifugal Compressor Rotor Repair . . . . . . . . . . . . . . . . . . 501
Compressor Rotor Repairs. Impeller Manufacture. Compressor Impeller Design
Problems. Impeller Balancing Procedure. Rotor Bows in Compressors and
Steam Turbines. Clean-Up and Inspection of Rotor. Disassembly of Rotor for
Shaft Repair. Shaft Design. Rotor Assembly. Shaft Balancing. Rotor Thrust in
Centrifugal Compressors. Managing Rotor Repairs at Outside Shops. Mounting
of Hydraulically Fitted Hubs. Dismounting of Hydraulically Fitted Hubs.
10 Protecting Machinery Parts Against Loss of Surface . . . . . . . 536

Basic Wear Mechanisms. Hard-Surfacing Techniques. Special Purpose Mate-
rials. The Detonation Gun Process. Selection and Application of O-Rings.
Appendix 10-A—Part Documentation Record. Procedures and Materials Used
for Hard-Surfacing.
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 617
vii
Foreword
A machinery engineer’s job was accurately described by this ad, which ap-
peared in the classified section of the New York Times on January 2, 1972:
Personable, well-educated, literate individual with college degree
in any form of engineering or physics to work Job requires wide
knowledge and experience in physical sciences, materials, con-
struction techniques, mathematics and drafting. Competence in the
use of spoken and written English is required. Must be willing to
suffer personal indignities from clients, professional derision from
peers in more conventional jobs, and slanderous insults from
colleagues.
Job involves frequent physical danger, trips to inaccessible loca-
tions throughout the world, manual labor and extreme frustration
from lack of data on which to base decisions.
Applicant must be willing to risk personal and professional
future on decisions based on inadequate information and complete
lack of control over acceptance of recommendations
The situation has not changed. As this third edition goes to press, there is an
even greater need to seek guidelines, procedures, and techniques that have worked
for our colleagues elsewhere. Collecting these guidelines for every machinery
category, size, type, or model would be almost impossible, and the resulting ency-
clopedia would be voluminous and outrageously expensive. Therefore, the only
reasonable course of action has been to be selective and assemble the most impor-
tant, most frequently misapplied or perhaps even some of the most cost-effective

maintenance, repair, installation, and field verification procedures needed by
machinery engineers serving the refining and petrochemical process industries.
This is what my colleagues, Heinz P. Bloch and Fred K. Geitner, have suc-
ceeded in doing. Volume 3 of this series on machinery management brings us the
know-how of some of the most knowledgeable individuals in the field. Engineers
and supervisors concerned with machinery and component selection, installation,
and maintenance will find this an indispensable guide.
Here, then, is an updated source of practical reference information which the
reader can readily adapt to similar machinery or installations in his particular
plant environment.
Uri Sela
Walnut Creek, California
viii
Acknowledgments
It would have been quite impossible to write this text without the help and
cooperation of many individuals and companies. These contributors have earned
our respect and gratitude for allowing us to use, adapt, paraphrase, or otherwise
incorporate their work in Volume 3: W. J. Scharle (Multi-Plant Maintenance),
J. D. Houghton (Planning Turbomachinery Overhauls), E. M. Renfro/Adhesive
Services Company (Major Machinery Grouting and Foundation Repair), M. G.
Murray (Grouting Checklists, Machinery Alignment), Prueftechnik A. G. (Laser
Alignment), P. C. and Todd Monroe (Machinery Installation Checklists and Pre-
Grouted Baseplates), J. W. Dufour (Machinery Installation Guidelines), W.
Schmidt (Piping Connection Guidelines), Garlock Sealing Technologies and Flex-
itallic, Inc. (Gasket Selection and Flange Torque Requirements), D. C. Stadel-
bauer, Schenk Trebel Corporation (Balancing of Machinery Components), MRC
Division of SKF Industries (Bearing Installation and Maintenance), Flowserve
Corporation (Metallic Seal Installation, Repair, Maintenance), H. A. Scheller
(Pump Packing), T. Doody (Welded Repairs to Pump Shafts, etc.), H. A. Erb
(Repair Techniques for Machinery Rotor and Case Damage), Byron Jackson,

Division of Flowserve Corporation (Field Machining Procedures), Terry Wash-
ington, In-Place Machining Company (Metal Stitching Techniques), Tony Casillo
(OEM vs. NON-OEM Machinery Repairs), Barney McLaughlin, Hickham Indus-
tries, Inc., and W. E. Nelson (Compressor Rotor and Component Repairs, Sealing
Compounds, etc.), M. Calistrat/Koppers Company (Mounting Hydraulically
Fitted Hubs), Larry Ross, C. R. McKinsey and K. G. Budinski (Hard Surfacing),
C. R. Cooper, Van Der Horst Corporation (Chrome Plating), Turbine Metal Tech-
nology (Diffusion Alloys) and National O-Ring Company (O-Ring Selection and
Application).
We also appreciate our close personal friend Uri Sela who devoted so much of
his personal time to a detailed review of the entire draft, galleys, and page proofs.
Uri counseled us on technical relevance, spelling, syntax, and other concerns.
More than ever before, we are reminded of some important remarks made by
Exxon Chemical Technology Vice President W. J. Porter, Jr. in early 1984. Mr.
Porter expressed the belief that through judicious use of outside contacts, partic-
ipation in relevant activities of technical societies, and publication of pertinent
material, we can be sure that our technical productivity will continue to improve.
The technical person will thus be updated on the availability of “state-of-the-art”
tools and individual creativity encouraged.
We hope this revised text will allow readers to find new and better ways to do
their jobs, broaden their perspective as engineers, and contribute to a fund of
knowledge which—if properly tapped—will bring benefits to everyone.
Heinz P. Bloch
Fred K. Geitner
ix
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Part I
Background to
Process Machinery
Maintenance

Programming
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Chapter 1
Machinery Maintenance:
An Overview
Maintenance and repair of machinery in a petrochemical process plant
was defined in a preceding volume as simply “defending machinery
equipment against deterioration.”
1
Four strategies within the failure-
fighting role of maintenance were defined:
•
Preventive
•
Predictive
•
Breakdown or demand based
•
“Bad actor” or weak spot management
Machinery maintenance can often be quite costly in a petrochemical
plant operation. Prior to the publication of the first two volumes of this
series, very few studies were available describing quantitative or objective
methods for arriving at the optimization of the four strategies
2
. Though
our readers should not expect detailed contributions to those subjects in
this volume, we did opt to include an overview section describing the
maintenance philosophy practiced in a large multi-plant corporation which
makes effective use of centralized staff and computerized planning and
tracking methods.

What, then, can our readers expect? After a short definition of the
machinery maintenance problem we will highlight centralized main-
tenance planning. We will then guide our readers through the world of
machinery maintenance procedures by identifying the What, When,
Where, Why, How—and sometimes Who—of most maintenance and
repair activities around petrochemical process machinery. We ask,
however, that our readers never lose sight of the total picture. What, then,
is the total picture?
3
It is the awareness that true cost savings and profitability can only be
achieved by combining machinery reliability, safety, availability, and
maintainability into a cost-effective total—consistent with the intent of
our series of volumes on process machinery management. Figure 1-1
illustrates this concept. Consequently, machinery maintenance cannot be
looked at in isolation. It will have to be governed by equipment failure
experience, by our effectiveness in failure analysis and troubleshooting
1
,
and by built-in reliability
3
.
Maintenance in a broad definition is concerned with controlling the
condition of equipment. Figure 1-2 is a classification of most machinery
maintenance problems.
Deterministic or predictive component life problems are those where
no uncertainty is associated with the timing or consequence of the main-
tenance action. For example, we may have equipment whose components
are not subject to actual failure but whose operating cost increases with
time. A good illustration would be labyrinths in a centrifugal process com-
pressor. To reduce operating cost caused by increasing leakage rate, some

form of maintenance work can be done—usually in the form of replace-
ment or overhaul. After maintenance the future trend in operating cost is
known or at least anticipated. Such a deterministic situation is illustrated
in Figure 1-3.
4 Machinery Component Maintenance and Repair
Figure 1-1. The total picture: Possible goals of process machinery management.
Machinery Maintenance: An Overview 5
Figure 1-2.
Classification of machinery maintenance problems.
In probabilistic or indeterminate component life problems, the timing
and result of maintenance may depend on chance. In the simplest situa-
tion a piece of machinery can be described as being “good” or “failed.”
From a frequency distribution of the time elapsed between maintenance
activity and failure it is possible to determine the variations in the proba-
bility of failure with elapsed time. These relationships are thoroughly dealt
with in Reference 1.
We saw from Figure 1-2 that inspection, overhaul, repair and finally
replacement are common to all maintenance strategies. The basic purpose
of inspection is to determine the condition of our equipment. All machin-
ery inspection should be based on these considerations:
1. Expected failure experience:
•
Deterministic
•
Probabilistic
2. Inspection cost.
3. Probability and risk of failure.
4. Probable consequences of failure, i.e., safety-health and business
loss.
5. The risk that inspection will cause a problem

4
.
6. The quality of on-stream condition monitoring results.
The terms overhaul and repair are often reserved for maintenance
actions that improve the conditions of an item, but may or may not establish
“good as new” condition. In fact, overhaul is often interpreted as a preven-
tive maintenance action while repair is strictly reserved for maintenance of
an item that has reached a defined failed state or defect limit
5
. Replacement
should be understood in our context as a broad term that includes the
replacement of components, operating fluids and charges, as well as of
complex machinery and systems. Finally, we understand organizational
structure problems in machinery maintenance as those concerns that deal
with maintainability parameters such as facilities, manpower, training, and
tools. Figure 1-4 illustrates this point.
6 Machinery Component Maintenance and Repair
Figure 1-3. Deterministic trend in costs.
Most petrochemical process plants have a preventive maintenance (PM)
system. The authors know of a plant where 95 percent of the maintenance
work orders are turned in by the PM crews and not the operators. While
this is an extreme—and probably not a very cost effective—way of failure
fighting, we can support a moderate approach to machinery PM. This
moderate approach begins with an attempt to plan all PM actions by
following this pattern:
1. Determine what defect, failure, or deterioration mode it is you want
to prevent from occurring.
2. Determine whether the defect, failure, or deterioration mode can be
prevented by periodic actions. If not, determine how it can be pre-
dicted and its consequence reduced by perhaps continuous or daily

surveillance.
3. Select PM task.
4. Determine normal life span before defect, failure, or deterioration
mode will develop.
5. Choose PM interval within normal life span.
6. Determine who should do the job—operating crew or maintenance
personnel.
More often than not we will find that machinery failure modes are prob-
abilistic and indeterminate. PM will therefore not help and predictive
strategies are indicated: By continuously looking for problems, we expect
not to reduce the deterioration rate of machinery components, but to
control the consequences of unexpected defect or failure. This mainte-
nance strategy is often referred to as predictive- or condition-based main-
tenance. Together with “post mortem” failure analysis, this strategy is the
Machinery Maintenance: An Overview 7
Figure 1-4. Process machinery maintainability components.
most powerful weapon in the arsenal of the machinery maintenance
person. Figure 1-5 shows how predictive maintenance works in connec-
tion with large petrochemical process machinery such as turbocompres-
sors, reciprocating compressors, and their drivers.
8 Machinery Component Maintenance and Repair
Figure 1-5. Machinery predictive maintenance routine (adapted from Ref. 6).
Machinery Maintenance: An Overview 9
Table 1-1
State-of-the-Art Instrumentation and Monitoring Methods
The fundamental difference between preventive maintenance and
predictive- or condition-based maintenance strategies is that PM is carried
out as soon as a predetermined interval has elapsed, while condition-based
maintenance requires checking at predetermined intervals, with the main-
tenance action carried out only if inspection shows that it is required. The

main factors in a predictive machinery maintenance program are:
•
State-of-the-art instrumentation and monitoring methods as shown in
Table 1-1
•
Skilled analysts
•
Information system allowing easy data retrieval
•
Flexible maintenance organization allowing for an easy operations/
maintenance interface
•
Ability to perform on-line analysis
7
In the following chapters we will further deal with predictive main-
tenance tools.
References
1. Bloch, H. P and Geitner, F. K., Machinery Failure Analysis and Trou-
bleshooting, Gulf Publishing Company, Houston, Texas, third edition,
1997, Pages 484–488.
2. Jardine, A. K. S., The Use of Mathematical Models in Industrial Main-
tenance, The Institute of Mathematics and its Applications, U.K.,
August/September 1976, Pages 232–235.
3. Bloch, H. P., Improving Machinery Reliability, Gulf Publishing
Company, Houston, Texas, third edition, 1998, Pages 1–667.
4. Grothus, H., Die Total Vorbeugende Instandhaltung, Grothus Verlag,
Dorsten, W. Germany, 1974, Pages 63–66.
5. Reference 2, Page 232.
6. Fucini, G. M., Maintenance Shops, Quaderni Pignone, Nuovo Pignone,
Firenze, Italy, Number 27, 1983, Page 30.

7. Baldin, A. E., “Condition-Based Maintenance,” Chemical Engineering,
August 10, 1981, Pages 89–95.
Bibliography
Whittaker, G. A., Shives, T. R., and Philips, Technology Advances in
Engineering and Their Impact on Detection, Diagnosis and Prognosis
Methods, Cambridge University Press, New York, New York, 1983,
Pages 11–286.
10 Machinery Component Maintenance and Repair
Chapter 2
Maintenance Organization
and Control for Multi-Plant
Corporations*
There are many approaches to performing maintenance and engineer-
ing activities at an operating facility. The type of process, plant size, loca-
tion, and business conditions at a particular time are all variables that can
affect this approach. The system must fit the basic overall corporate goals.
The final evaluation of success, however, for whichever system selected,
is achieving the lowest possible product cost over extended periods of time
at varying business conditions.
This segment of our text will concentrate on plant maintenance and
engineering service in a multi-plant corporation operated on a combina-
tion centralized-decentralized basis. However, the reader will quickly
discern the applicability of this approach to many aspects of equipment
maintenance in “stand-alone” plants. Organizational control methods are
all planned for an optimum approach to cost economy. Basically, then, we
are presenting corporate management’s approach to an overall mainte-
nance strategy. This approach is as valid in 2004 as it has been in the
1965–1970 time period.
11
* Based on articles by W. J. Scharle (“Multi-Plant Maintenance and Engineering Control,”

Chemical Engineering Progress, January 1969) and J. A. Trotter (“Reduce Maintenance
Cost with Computers,” Hydrocarbon Processing, January 1979). By permission of the
authors. Updated in 2004.
Type of Operation
To understand the organizational approach to maintenance and engi-
neering described here, it is first necessary to understand the size and type
of operations involved. We should assume that the facilities would fall into
virtually all size categories. The plants are quite autonomous and may
select maintenance organizations to fit their particular needs. Through
their own unique experiences of plant maintenance and engineering
problems and studying alternative approaches used by others, a mature
organization will have gradually formulated an operations control system,
including plant maintenance and engineering services, which best serves
its type of operation and is flexible for future needs.
This implies that large plants, which have the technical and maintenance
support resources to be totally self-sufficient, may opt to deviate from
the organizational and implementation-oriented setups we are about to
describe. However, for best results, the deviation should not be very drastic
because the basic principles of effective maintenance organization and
control hold true for any plant environment.
Before discussing plant maintenance specifics and engineering
functions, we will discuss why this multi-plant corporation went to the
present approach. Like many companies, the corporation started with
an approach wherein the plant manager was autonomous in his respon-
sibility for production, maintenance, and most engineering services.
He depended largely on the equipment manufacturer to help solve
problems.
As more plants were added to the network and more significant opera-
tional and mechanical problems were encountered, it was gradually
recognized that the most economical solution to critical problems was

to quickly interject the best technical specialists within the company,
regardless of location. However, it was not possible or economical to
have these highly skilled specialists at each facility or to adequately
train the plant manager in all areas when the facility normally operated
at an extremely high onstream factor. Again, as a higher degree of tech-
nical knowledge was gained, equipment improvements made, and sophis-
ticated process and machinery monitoring devices introduced, it was
found that the periods between major equipment maintenance could be
significantly extended without risking costly equipment failures. The use
of a relatively small group of mobile, technical specialists from within
the company was the key to better plant performance and lower costs.
Equipment manufacturers and vendors’ representatives have neither the
incentive nor the responsibility to provide the prompt technical services
required.
12 Machinery Component Maintenance and Repair
Manager’s Role
Yet, it was strongly desired to have these specialists report to and work
solely under the guidance of the individual plant manager in order not to
confuse the chain of command. Thus, a decentralized system of giving the
plant manager responsibility for general operations, cost performance, and
maintenance performance, but with a strong centralized approach to all
aspects of monitoring plant performance and providing specific mainte-
nance and engineering services as required, was evolved as the funda-
mental organizational concept. Once this basic concept was reached,
efforts were then devoted to understanding and establishing specific
methods of accomplishing plant maintenance and engineering services
under the general system concept.
Since the plant managers’ responsibilities on a decentralized basis rep-
resented a rather conventional approach to day-to-day operation, we will
dwell on considerations relative to the centralized aspect of plant mainte-

nance and engineering services and the monitoring function. These cen-
tralized services were provided by a group of specialists located for the
most part at the home office or at the location of the largest affiliated plant.
Some advantages of this centralized approach to plant maintenance and
engineering services are:
1. Better solutions to important technical problems. With the varied
plant problems, the ability to use key specialists will normally result
in the best technical solution.
2. More efficient use of talent. With extremely high onstream factors,
chemical and mechanical engineering specialists at each facility
cannot be fully justified, since the rate of problems and/or severity
would not normally warrant their continuous presence. Minimum
staffing at each plant to handle normal day-to-day problems, plus a
mobile technical and maintenance organization will result in lower
overall costs. The question of overstaffing at a particular facility to
take care of “first year” startup problems is a very real one. The
ability to have this same mobile specialist group help in quickly
solving first year operation problems allows a flexible and easy
method of reducing a facility to its minimum labor cost at the earli-
est time.
3. Better communication. Technical solutions, procedures, and other
important factors which have a direct and immediate effect on
on-stream factors and costs can be more readily transmitted from
one plant to another. The use of plant shutdown and maintenance
reports prepared by the plant manager allows the central technical
Maintenance Organization and Control for Multi-Plant Corporations 13
organization to evaluate and disseminate information pertinent to
other facilities.
4. Better response to management and business outlook. Constantly
varying market conditions change product demand and value. These

important factors often become the overriding consideration in
scheduling maintenance work and turnarounds. Centralized overall
maintenance planning can more readily assimilate these factors in
considering a large number of plants at different locations. This is
an important consideration in minimizing peaks and valleys in major
maintenance work and allowing a smaller specialist group to handle
a broader scope of activities.
5. More consistent organizational policies, procedures, and better
methods of making comparisons on general performance, cost, pro-
duction, prompt action, and managerial talent.
To keep the centralized organization current on the facts of life at plant
facilities, a program of specialist and management visits to each facility
must be established. These visits, coupled with careful production moni-
toring, normal maintenance, and general cost performance are necessary
prerequisites for the system discussed herein. The extra travel and com-
munication costs are far outweighed by better personnel utilization.
Maintenance
Total plant profitability is obviously affected both by onstream factors
and maintenance costs. One cannot be separated from the other. Any
system, therefore, must account for how cheaply maintenance can be
performed from an organizational setup, and also what must be done and
how often. The ability to update maintenance requirements and improved
planning based on experience at a group of plants has a large bearing on
overall maintenance costs.
Other than breakdown maintenance, all maintenance work is planned.
Some can be done while the plant is operating and the rest during shut-
down. The effectiveness of this planned or preventive maintenance (PM)
program to reduce breakdowns and the organizational methods used to
accomplish the planned major maintenance work will determine mainte-
nance costs. Preventive maintenance as discussed here covers all planned

maintenance work, whether major or minor, regardless of whether the
plant is running or shut down. The selection of what shall be done as part
of the PM program and how often it shall be done is one of the most
important factors affecting corporate maintenance costs and the realiza-
tion of an optimum onstream factor.
14 Machinery Component Maintenance and Repair