Bolt Static Analysis v1.2.0 – Comprehensive analysis
- Various changes to parameters notation, both in the user interface and in the report, to improve consistency between them
- Eliminated the bolt group parameters for Minimum distance of bolt hole to flange edge and Minimum distance of bolt hole to counterpart edge. This information was moved to become an individual parameter for each plate. When loading a BSA file generated with a previous version, it will automatically be updated as follows:
- The Minimum distance of bolt hole to flange edge will be assigned as Bolt hole to plate edge for all plates except the bottom one
- The Minimum distance of bolt hole to counterpart edge will be assigned as Bolt hole to plate edge for the last plate in the stack (the bottom plate)
- Updated the report to include the new parameter for Bolt hole to plate edge, for every plate
- Added a control to enable the user to override the number of contact areas between the plates. When set to 0 (default) the number of contact areas is automatically calculated as the number of plates - 1
- Added the possibility to specify the bolt preload either as:
- the fraction of bolt tensile yield stress to be reached when the bolt is loaded (also known as coefficient of utility) or
- the nominal installation torque at reference temperature
- Updated the pop-up message shown when the user loads a BSA file created with an older version. Now the message displays a detailed list of the changes made (if any) in order to update the file to the latest version
- Corrected the calculation of margin of safety for thread pull-out (
) to use maximum preload including thermal load instead of maximum preload without thermal load
Previous calculation : 
Current calculation : 
where
 |
Critical fastener load for failure of thread (minimum between male and female thread) |
 |
Maximum preload without thermal load |
 |
Maximum preload including thermal load |
 |
Joint stiffness ratio which accounts for bolt loading plane factor |
 |
Derived maximum external axial bolt load, when moments loads are considered |
 |
Ultimate safety factor |
- Corrected the calculation of necessary length of the engaged thread (
)
Previous calculation : 
Current calculation : 
where
|
Critical fastener load for failure of thread (minimum between male and female thread) |
 |
Axial load transmitted by the thread |
 |
Bolt thread pitch |
 |
Bolt major diameter |
 |
Bolt pitch diameter |
 |
Bolt thread angle |
 |
Minor diameter of the female thread |
 |
Empirical coefficient accounting for the depth of supporting material behind the female thread |
 |
Empirical coefficient accounting for the strength ratio of the two threads |
 |
Shear ultimate strength of the bolt material |
 |
Shear ultimate strength of the material forming the female thread. Equal to: Shear ultimate strength of nut material if counterpart is a nut Shear ultimate strength of last plate material if counterpart is threaded insert Shear yield strength of helicoil material if counterpart is threaded insert with helicoil |
- Corrected the calculation of margin of safety on fastener failure for combined loads, yield (
)
Previous calculation : 
Current calculation : 
where
 |
Fastener strength utilization ratio (axial, yield) |
 |
Fastener strength utilization ratio (shear, yield) |
- Corrected the calculation of margin of safety on fastener failure for combined loads, ultimate (
)
Previous calculation : 
Current calculation : 
where
 |
Fastener strength utilization ratio (axial, ultimate) |
 |
Fastener strength utilization ratio (shear, ultimate) |
- Corrected the calculation of margin of safety on plate hole bearing stress, yield (
) for every plate (i = plate index)
Previous calculation : 
Current calculation : 
where
 |
Bearing yield of plate i, linearly interpolated between |
 |
Nominal bolt hole diameter of plate i |
|
Bolt major diameter |
 |
Thickness of plate i |
 |
Derived maximum radial bolt load, when moments loads are considered |
 |
Yield safety factor |
 |
Joint fitting safety factor |
and 
- Corrected the calculation of margin of safety on plate hole bearing stress, ultimate (
) for every plate (i = plate index)
Previous calculation : 
Current calculation : 
where
 |
Bearing ultimate of plate i, linearly interpolated between  and  |
|
Nominal bolt hole diameter of plate i |
|
Bolt major diameter |
|
Thickness of plate i |
|
Derived maximum radial bolt load, when moments loads are considered |
|
Ultimate safety factor |
|
Joint fitting safety factor |
- Corrected a bug in the representation of the compression zone, in the bolted joint drawing, whereby when this was a full sleeve the compression zone would extend beyond the counterpart or nut. This bug only affected the visual representation of the compression zone and not the calculations.