The Tech-Spring project has enabled the technical performance of springs to be improved. This was accomplished through a scientific understanding of residual and applied stress profiles. The improvements have been incorporated into a Toolkit which is being used by project partners.

In order to acquire an improved understanding of the stresses in springs, the project partners devised a series of case studies, investigating real life scenarios which required explanation. These case studies were accepted into the project providing that they involved using one or more of the stress analysis methods that were to be studied. In this way the stress analysis methods were applied systematically to solve problems, and this enabled an assessment of each method.

Some stress analysis methods were found to be universally useful – load/torque testing, use of classical mechanical stress formulae, CAD programs. Other stress analysis methods were found to be useful on a case by case basis – use of strain gauges for verification of applied stresses, use of X-ray methods for residual stress measurement, use of a high speed camera (often in conjunction with strain gauges) to indicate the actual dynamic deflection of springs on test or in use. Finally there were stress analysis methods that did not bring technical or commercial advantages to SME spring manufacturers, like finite element analysis (which worked well on occasions, but was too slow and expensive, and better ways were identified), MKS, photo-elastic films.

The technical performance improvements that have been included in the Toolkit include:

The partners in Tech-Spring agree that the results have been extremely interesting and informative. The project has highlighted which investigative methods should be used to solve the problems that arise with springs. For more information, visit the Tech-Spring website at