Calculation Software for Mechanical, Structural, Hobbyist Designers

Free! Bolt Stress Calculator


Our Features

Digitool offers web based calculation software for mechanical, structural and hobbyist designers. Currently we offer free bolt design software for tension, moment and torsion resisting joints. The software is able to accept combined load conditions for user specified bolt positions. The next release will be a weld design tool for combined load connections, which will enable the designer to size the leg length of the weld.

When analysing components which contain bolted and welded connections using Finite Element Analysis (FEA) software it is common practice to assume these connections are fully bonded. The forces and moments experienced by the connection can then be extrapolated from the analysis and a separate side study can be conducted. The reason for this is that in order to correctly define the connections in a FEA, a set of non-linear contact conditions need to be set up, which could potentially increase the processing time and complexity of the analysis. With the Digitool suite of software tools these connections can be analysed quickly and efficiently thus reducing the processing time overhead.

It is common practice in industry to assume that full penetration welds give the same strength as the parent metal and subsequently can be analysed as a fully bonded connection. However, the ability of a partial penetration or fillet weld to resist loads and moments depends on their effective throat length. A separate calculation can be performed using the extrapolated forces and moments from the FEA to avoid the need for a non-linear analysis.

Designed to supplement commercial FEA software

Reduce processing time by separating out more rudimentary calculations such as bolted and welded connections.

Visual Stress Plots

Visual indications highlighting components with the highest stress levels


Designed using responsive web technology so the software will look as good on a mobile phone as it does on your desktop.

Reduces the need for repetitive hand calculations

Eliminates potential errors in creating hand calculations. Just check the inputs not the workings.