Information related to Bolted Joints
Presented below are links to pages on specific topics related
to bolted joint technology.We specialise in this subject and
have extensive knowledge and experience on the solution of
problems related to bolted joints. Please contact
us if you think we can be of assistance on a problem that
you are experiencing. Click on appropriate link for further
information on the subject.
Published
articles on bolting related matters
The Bolt Science Quiz on Bolting
Glossary
of fastener and related terms
Torque
Convertor - Conversion program for torque units
Methods
of Tightening Bolts
Bolt
Tightening and Quality Control
Case
Study - Torque Tightening
The
Jost Effect - Why nuts and bolts come loose!
Strength
of Threaded Fasteners
Bolted
Joints containing Gaskets
Frequently
Asked Questions
The
Importance of Preload - The Joint Decompression Point
Bolt
Crosstalk and the need for a Tightening Sequence
Tightening
the Nut or the Bolt Head
Use
of Two Nuts to Prevent Self Loosening
Untightening
of nuts and bolts
When is a back-up wrench needed?
Is a torque value really needed?
Should there be a tolerance on a torque value?
Is double clicking of a torque wrench, good or poor practice?
World Standards Day - The importance of standards to fasteners
What is the optimum value for the coefficient of friction of a threaded fastener?
The Reduced Loadability of DIN nuts
ISO68-1 The basic and design thread profiles
The Causes of Non-Linear Torque Tension Relationships during Tightening
Joint bearing pressure and the use of unsuitable washers
The Importance of Friction in Friction Grip Joints
The use of Friction Shims in Friction Grip Joints
Friction grip joints - A calculation study.
Loosening Characteristics of Prevailing Torque Nuts
Tutorial
on the theory of Bolted Joints Why
is a bolt's preload force vital? How
a bolted joint sustains an applied force What
is a Joint Diagram? Joint
Diagram with an external force applied The
effect of a high external force on a joint The
effect of a compressive external force on a joint The
Effect of Joint Deformation loss due to Embedding Bolt
Preload Variation due to the Tightening Method Bolted
Joint Analysis using Preload Requirement ChartsUsing a Design Margin or a Probability of Failure Approach to Bolted Joint Design
Why
nuts and bolts come loose
Poster
on why nuts and bolts can come loose
Video
- Junker Fastener Vibration Test
Tests
on the double nut system of locking
Tests
on helical spring washers
Vibrational Detachment
of Threaded Fasteners
Non-Rotational Loosening of Nuts and Bolts
Preload Loss from Embedding in Bolted Joints
Preload Loss from Stress Relaxation in Bolted Joints
Bolt Self-Loosening and the Critical Slip Distance
The importance of the grip length to bolt diameter ratio
Information
related to screw threads
Historical
background to screw threads
Basic
Thread Terminology
The
Whitworth Thread Form
The
British Association Thread Form
The
Unified and Metric Thread Forms
Basic
Profile of Unified and Metric Thread Forms
Bolt fatigue and a Bolt's Thread Root
Tolerancing
of Screw Threads
Miniature Screw Threads
Examples
of bolt failures
Which Types of Bolt Failure Are Most Common?
M24
Engine Mounting Bolt Failure
M16
Bolt Failure
M12
Bolt Fretting Failure
Wheel
Stud Failures
Short
Bolting - Ensuring sufficient thread engagement
The
Effect of Nut Face Angularity on Bolt Fatigue Life
The
Bolt Science Blog
Review
of a technical paper titled 'Self loosening of prestressed
bolts'
Review
of a technical paper titled 'Prevention of failures of high
strength fasteners in use in offshore and subsea applications'
Contributed
Articles
Talking
about Torque by George Lorimer
Smartools
for Fastening by George Lorimer
Tightening
Bolts & Relaxation by George Lorimer
When
in Rome by George Lorimer
More
on Relaxation by George Lorimer
More
Thoughts on Fastening by George Lorimer
Torque
versis Torque+Angle Tightening - a case study by George Lorimer
Video
and Other Material
Video
on a Junker Transverse Vibration Test on Fasteners
Newsletters
2025 August Newsletter -
The Silent Killer of Wheel Bolts
2025 July Newsletter -
Miniature Screw Threads
2025 June Newsletter -
Is double clicking of a torque wrench good or bad practice?
2025 May Newsletter -
Loosening Characteristics of Prevailing Torque Nuts
2025 April Newsletter -
Using a Design Margin or a Probability of Failure Approach. Part 2
2025 March Newsletter -
Using a Design Margin or a Probability of Failure Approach. Part 1
2025 February Newsletter -
Friction Grip Joint Calculation Example Study
2025 January Newsletter -
The use of friction shims in bolted joints
2024 December Newsletter -
The Importance of Friction in Friction Grip Joints
2024 November Newsletter -
Helical Spring Washers
2024 October Newsletter -
Joint bearing pressure and the use of unsuitable washers
2024 July Newsletter -
Bolt Fatigue and a Bolt's Thread Root
2024 April Newsletter -
Tightening Multiple Bolts and Elastic Interaction
2024 March Newsletter -
Which Types of Bolt Failure Are Most Common?
2024 January Newsletter - Non-Linear Torque-Tension Relationships during Tightening
2023 November Newsletter - ISO 68-1 The Basics of the Metric Thread Form
2023 September Newsletter - Recent Update to ISO Nuts
2023 August Newsletter - The
Reduced Loadability of DIN compared to ISO Nuts
2023 July Newsletter - The Goldilocks Zone and the Coefficient of Friction of Fasteners
2023 June Newsletter - The Joint Decompression Point - Why Bolt Preload is Important!
2023 May Newsletter - What is a Residual Torque Measurement.
2023 April Newsletter - Case study of fastener issues causing a rail accident
2023 March Newsletter - Is it okay to use a mild steel nut with a high tensile bolt?
2020 August - Vibrational Detachment of Threaded Fasteners
2020 July - How do we know what size of bolt to use?
2020 May - When is a back-up wrench needed?
2020 April - The use of two nuts to lock a fastener
2020 March - Fatigue Failure of an M16 Flanged Bolt
2020 January - A new approach to the tightness checking of bolts
2019 December - Problem with loose screws
2019 November - New Thoughts on Hydrogen Embrittlement of 10.9 Bolts