Eric Summer carrying the DART repair tool in its compact, portable case.
We are thrilled to celebrate Eric Summer’s tenth work anniversary at Hill Engineering! Since joining the team in July 2014, Eric has made invaluable contributions to our design and automation efforts. His journey began in a technical role, and while his core responsibilities have remained the same, Eric has become the go-to person for fixing “random stuff” around the office and tackling odd jobs that fall outside traditional roles.
The incremental hole drilling method is one of the most common residual stress measurement techniques employed at Hill Engineering. A reliable and rapid process, it’s the subject of our latest Residual Stress 101 episode.
In the ever-evolving landscape of materials science and engineering, on-site solutions are an important component of residual stress testing. That’s why we at Hill Engineering have a dedicated residual stress field team, capable of traveling directly to customers’ locations in order to deliver the same precision and data quality of our in-house residual stress measurements.
Hill Engineering has been recently issued its second US patent for the DART™ measurement system. This updated device offers improved residual stress measurements within small-diameter pipe applications, allowing for more accurate analysis in both in-laboratory and non-laboratory settings.
TrueSlot® is an innovative technique for measuring near-surface residual stress that is more reliable than conventional techniques.
TrueSlot® is a residual stress measurement technique for generating a profile of residual stress versus depth from the material surface. The stress computation is similar to slitting but offers more sensitivity near the surface due to the proximity of the strain gage.
Additionally, TrueSlot® is globally less invasive than slitting because the volume of removed material is localized to the surface and does not typically extend through most of the specimen thickness.
A model of a completed TrueSlot® method measurement.
The physical application of TrueSlot® is like hole drilling, however instead of a shallow hole being milled into the body of a specimen containing residual stress, the material removed is a shallow slot. The strain released with each incremental slot depth is measured near the slot using a strain gage.
TrueSlot® is useful for
Production quality control applications
Applications requiring in-field measurements with portable equipment
Near-surface residual stress determination
Parts with large or complex geometry
Applications with challenging measurement access
Applications requiring rapid turn time
TrueSlot® was found to have better repeatability when compared with conventional x-ray diffraction.
Results from the method repeatability study which found TrueSlot® to be a more repeatable measurement method than XRD
Eric Summer and I recently packed up the DART repair tool for a trip down to Naval Base Ventura County in Port Hueneme, CA. There, we participated in the Navy’s Repair Technology Exercise, or REPTX 2022. Onboard the Navy’s Self Defense Test Ship (SDTS), Hill Engineering demonstrated how the DART repair tool can be applied as an industrial maintenance solution.