Tribology Series

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Synopsis
This introduction explains the nature of the various types of tribological components in machines, and categorises them according to the contact conditions and the way in which movement is accommodated. The fundamentals of friction and lubrication are explained, with an emphasis on the practical aspects and the way in which the theory applies to real machines

Index to Paper

• BEARING SURFACES
• CONTACT CONDITIONS
• FLUID FILMS
• BEARING APPLICATIONS

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Introduction - Basic Concepts in Tribology

Ref:	TRTN1-2
Author:	Neale Consulting Engineers Ltd.
Pages:	14
Tables:	2
Figures:	13

Synopsis
These notes explore the basis of tribological sliding interactions on a micro scale, covering the real nature of engineering surfaces, surface films, boundary lubrication and fluid film lubrication. The emphasis is on practical information, not on abstract theory.

Index to Paper

• INTRODUCTION
• THE NATURE OF SURFACES
  • PHYSICAL: SURFACE TEXTURE
  • CHEMICAL: SURFACE FILMS
• LUBRICATION
  • FLUID FILM LUBRICATION
  • BOUNDARY LUBRICATION
• SUMMARY

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Introduction - Basic Principles of Bearing Selection

Ref:	TRTN1-3
Author:	Neale Consulting Engineers Ltd.
Pages:	19
Tables:
Figures:	19

Synopsis
There are many types of bearing available, and the criteria for choosing one type over another are explained in simple terms. The fundamental speed and load limits of each type are explained, and practical charts and tables enable the best fundamental type for a given situation to be selected.

Index to Paper

• BEARING TYPES
• RUBBING BEARINGS
• POROUS METAL BEARINGS
• ROLLING ELEMENT BEARINGS
• FLUID FILM BEARINGS
• COMPARATIVE PERFORMANCE
  • SELECTION OF JOURNAL BEARINGS WITH OSCILLATING MOVEMENT FOR SPECIAL ENVIRONMENTS OR PERFORMANCE
  • SELECTION OF JOURNAL BEARINGS WITH CONTINUOUS ROTATION FOR SPECIAL ENVIRONMENTAL CONDITIONS
  • SELECTION OF JOURNAL BEARINGS WITH CONTINUOUS ROTATION FOR SPECIAL PERFORMANCE REQUIREMENTS

Introduction - Wear Mechanisms

Ref:	TRTN1-4
Author:	Neale Consulting Engineers Ltd.
Pages:	9
Tables:
Figures:	11

Synopsis
There are several different types of wear, including abrasive, adhesive, fretting wear etc., and one can also include material removal by surface fatigue, cavitation erosion and corrosion. In terms of machinery operation, all of these may be considered as wear. All these major mechanisms are explained, and methods of controlling them are explored.

Index to Paper

• WEAR MECHANISMS
  • ADHESIVE WEAR
  • FRETTING
  • FATIGUE
  • ABRASIVE WEAR
  • CAVITATION AND FLUID EROSION
  • CORROSION
• METHODS OF WEAR REDUCTION

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Plain Bearings: Bearing Materials

Synopsis
The fundamental requirements of a successful plain bearing material are described and explained, and examples are given for a range of types from soft whitemetals to relatively hard bronzes, and also cast-iron, and non metallic bearings, including typical strength and load ratings. Types of construction are described. Index to Paper

• MATERIAL REQUIREMENTS
  • MATERIAL TYPES
  • MATERIAL SELECTION
• BEARING TYPES
• LUBRICATED PLAIN BEARINGS
  • CHOICE OF BEARING METAL TYPE
  • WHITE METALS
  • COPPER ALLOYS

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Plain Bearings: Types & principles of lubricated bearings

Ref:	TRTN1-6
Author:	Neale Consulting Engineers Ltd.
Pages:	11
Tables:
Figures:	13

Synopsis
Hydrodynamic and hydrostatic (externally pressurised) bearings are explained in terms of the fundamental methods of generating the load-carrying oil film. This is a necessary precursor to using and understanding the calculation methods for analysing and designing fluid film bearings.

Index to Paper

• TYPES AND GENERAL PERFORMANCE
  • HYDROSTATIC BEARINGS
  • HYDRODYNAMIC BEARINGS

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Rolling Bearings: Types and Principles

Ref:	TRTN2-1
Author:	Neale Consulting Engineers Ltd.
Pages:	11
Tables:
Figures:	12

Synopsis
The various types of ball and roller bearing are shown, and the advantages and disadvantages of the various types are discussed. Guidance is given on which types are fundamentally more suited to particular conditions, such as high speeds, or high thrust loads. Misalignment, a common cause of failures, is discussed in relation to its affects on certain types of bearing.

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Synopsis
Rolling bearings are easily damaged by incorrect handling and installation, or by inadequate sealing. These notes give practical examples of how things go wrong in practice, and useful data and practical tips to help ensure good practice.

Index to Paper

• INTRODUCTION
• FITTING TOLERANCES
• AXIAL LOCATION
• PAIRED AND OPPOSED BEARINGS
• MOUNTING AND DISMOUNTING
• SEALING ARRANGEMENTS
• APPENDIX: BEARING FITTING CARDS

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Rolling Bearings: Lubrication

Ref:	TRTN2-3
Author:	Neale Consulting Engineers Ltd.
Pages:	20
Tables:
Figures:	10
References:	10

Synopsis
Grease lubrication and oil lubrication are both covered, with explanations of which is suitable for particular conditions. Types of grease and types and grades of oil are covered, and practical examples are given of failures due to inadequate lubrication arrangements.

Index to Paper

• NEED FOR LUBRICATION
• TYPE OF LUBRICANT
  • GREASE LUBRICATION
  • GREASE LIFE IN ROLLING BEARINGS
  • METHODS OF GREASE LUBRICATION
  • GREASE RELIEF VALVES
  • TYPE OF GREASE
  • OIL LUBRICATION
  • OIL LUBRICATION ARRANGEMENTS
  • EHD LUBRICATION IN ROLLING BEARINGS
  • EXAMPLES OF OIL-FILM FAILURES IN ROLLING BEARINGS
• REFERENCES

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Synopsis
These notes attempt to de-mystify the black art of lubricant selection. The viscosity grades for oil are explained, and charts give simple selection for certain machine types. The use of additives is discussed, and criteria given for when certain additives are required. Synthetic oils, greases, and solid lubricants are also covered.

Index to Paper

• INTRODUCTION
• SELECTION OF LUBRICANT VISCOSITY GRADE
  • JOURNAL BEARINGS
  • GEARS
  • ROLLING BEARINGS
• SELECTION OF OIL TYPE : QUALITY CHARACTERISTICS
  • VISCOSITY-TEMPERATURE CHARACTERISTICS
  • BOUNDARY LUBRICATION AND LOAD-CARRYING PROPERTIES
  • OXIDATION RESISTANCE
  • CORROSION PREVENTION PROPERTIES
  • POUR POINT
  • TOXICITY
• NON MINERAL OIL LUBRICANTS (SYNTHETIC LUBRICANTS)
  • GREASE
  • SOLID LUBRICANTS
  • CONCLUSION
• APPENDIX 1. VISCOSITY
  • DYNAMIC VISCOSITY
  • KINEMATIC VISCOSITY
• APPENDIX 2. GUIDE TO LUBRICANT SELECTION FOR INDUSTRIAL MACHINES

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Lubricants: Lubricating Oils in Service

Ref:	TRTN2-5
Author:	Neale Consulting Engineers Ltd.
Pages:	17
Tables:	4
Figures:	1

Synopsis
Deterioration of oils due to oxidation, loss of various properties, aeration, emulsification etc are all described. Recommendations on controlling these deterioration mechanisms, and pragmatic means monitoring and testing oil condition are given. Recommendations are given on filtration methods, and other means of maintaining oil systems in good condition and free from contamination.

Index to Paper

• INTRODUCTION
• DETERIORATION OF OILS
  • OXIDATION
  • LOSS OF CORROSION-PREVENTING ABILITY
  • AERATION AND FOAMING
  • CONTAMINATION
• SERVICE MONITORING
  • VISUAL ANALYSIS
  • LABORATORY ANALYSIS
  • VISCOSITY
  • ACIDITY
  • OTHER TESTS
• AIR ENTRAINMENT, FOAMING AND EMULSIFICATION OF LUBRICATING OILS IN SERVICE
  • AIR ENTRAINMENT AND FOAMING
  • EMULSIFICATION
• CONTAMINATION CONTROL
  • SELECTION OF FILTER RATING FOR LUBRICATION SYSTEMS
  • FILTERS
  • LUBRICANT CONTAMINATION
  • REQUIREMENTS OF LUBRICATED COMPONENTS
  • SELECTION OF FILTER RATING
  • RECOMMENDATIONS FOR THE SELECTION OF FILTER RATING
  • DESIGN OF FILTER ARRANGEMENTS
  • BYPASS CLEANING SYSTEMS
• RECOVERY OF USED OILS
  • RECLAMATION
  • RE-REFINING

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Gears - Lubrication

Ref:	TRTN2-6
Author:	Neale Consulting Engineers Ltd.
Pages:	17
Tables:	1
Figures:	11

Synopsis
The selection of the appropriate method of lubrication (manual, dip, or pumped circulation) is covered, together with recommendation for lubricant grade and lubricant type for various types of gears. Established scuffing criteria are also presented.

Index to Paper

• INTRODUCTION
• METHODS OF LUBRICANT APPLICATION
  • INTERMITTENT LUBRICATION
  • BATH LUBRICATION
  • OIL CIRCULATION
• LUBRICANT SELECTION FOR GEARS
  • SPUR AND HELICAL GEARS
  • WORM GEARS
• REQUIREMENT FOR LOAD-CARRYING ADDITIVES IN GEAR OILS
  • SPUR AND HELICAL GEARS
  • SCUFFING CRITERIA
• CONCLUSION

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Couplings: Types and Principles

Ref:	TRTN3-1
Author:	Neale Consulting Engineers Ltd.
Pages:	9
Tables:	2
Figures:	6

Synopsis
The multitude of different flexible coupling types are described and categorised according to their fundamental tribological and/or flexure characteristics, and the various types are compared in terms of their torque and speed limits. Since coupling mass can have a significant effect on the critical speed of a machine, a simplified calculation to make an approximate assessment of this is presented.

Index to Paper

• COUPLING TYPES
• EFFECT ON MACHINE VIBRATION

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Couplings: Selection

Ref:	TRTN3-2
Author:	Neale Consulting Engineers Ltd.
Pages:	11
Tables:	2
Figures:	3

Synopsis
Coupling selection for machines of high power and high speed is covered by these notes. Types covered include gear couplings, multiple membrane, contoured disc, and quill-shaft. The advantages and disadvantages of the different types are discussed, and practical performance boundaries are given.

Index to Paper

• INTRODUCTION
• COUPLING SELECTION
• RECOMMENDATIONS ON COUPLING SELECTION AND DESIGN

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Couplings: Lubrication

Ref:	TRTN3-3
Author:	Neale Consulting Engineers Ltd.
Pages:	9
Tables:
Figures:	4

Synopsis
These notes contain practical data on both grease and oil lubrication of gear couplings, including operational limits for various types of grease, and lubricant feed rates etc for oil lubrication. Features such as anti-sludge holes are described.

Index to Paper

• INTRODUCTION
• LUBRICATION MECHANISMS
• FILLED COUPLINGS
• CONTINUOUSLY-LUBRICATED COUPLINGS
  • METHOD OF LUBRICATION
  • TYPE OF LUBRICANT
  • AXIAL FORCE TRANSMISSION

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Seals: Types and Performance of Rotary Seals

Ref:	TRTN3-4
Author:	Neale Consulting Engineers Ltd.
Pages:	15
Tables:
Figures:	14

Synopsis
Sealing principles, and all the common types of rotary seal from packed glands to mechanical seals are described, with approximate performance in terms of speed, leakage rates etc. The less common types are also described briefly.

Index to Paper

• INTRODUCTION
• SEALING PRINCIPLES
• ROTARY SEALS
  • LIP SEALS
  • PACKED GLANDS
  • MECHANICAL SEALS
  • LIQUID BARRIER SEALS
  • LABYRINTH SEALS
  • THROTTLE BUSHES
  • SPECIAL SEALS
  • HYDROSTATIC SEALS
  • FERROFLUIDIC SEALS
  • HYDROKINETIC SEALS

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Seals: Mechanical Seals

Ref:	TRTN3-5
Author:	Neale Consulting Engineers Ltd.
Pages:	28
Tables:	6
Figures:	19

Synopsis
The mechanism of mechanical seals is described, and practical operating limits in terms of pressures, speeds, friction etc are given. Different seal materials are covered, and the variety of different installation methods are described, covering different cooling and flushing arrangements, and double seals etc.

Index to Paper

• INTRODUCTION
• BASIC PRINCIPLES
  • SEAL FACE LUBRICATION
• SEAL DESIGN AND OPERATING LIMITS
  • SPEED
  • FACE LOADING
  • FACE MATERIALS
• PRACTICAL EXPERIENCE
  • MECHANISM OF SEAL FACE LUBRICATION
  • SEAL ENVIRONMENT
• STATE OF THE ART
  • THE FUTURE
  • SEAL CHAMBER DESIGN
  • USE OF SPECIAL SEAL TYPES
  • GAS SEALS

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