Free Engineering Tool
Stress Concentration Factor Calculator
Look up Kt for common geometries — hole in plate, shoulder fillet, U-notch — using simplified Peterson’s chart data.
Results
Stress Concentration Factor
Typical Kt Values
| Geometry | Kt Range |
|---|---|
| Central hole in wide plate | ~3.0 (small d/W) |
| Shoulder fillet (D/d=2, r/d=0.1) | ~1.8–2.5 |
| U-notch | ~1.5–3.5 |
| Circumferential groove | ~1.5–3.0 |
⚠️ Note: These are approximate values from simplified curve-fit equations. For precise values, consult Peterson’s Stress Concentration Factors or perform FEA. Kt is for elastic analysis only.
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Nikolai Shelkovenko
Nikolai Shelkovenko is a vibration analysis engineer and the founder and CEO of Vibromera. For more than 15 years he has balanced rotating equipment in the field rather than on a test bench: mulchers, industrial fans, crushers, centrifuges, shafts and spindles. That work is what the Balanset instruments grew out of — they were designed as a tool a specialist can carry to the machine and use alone, on site, not as laboratory equipment. Vibromera was founded in 2017 and has been based in Porto, Portugal, since 2023. Development, assembly and support of the Balanset line all happen here. The flagship instrument is the Balanset-1A, a portable analyser for single- and two-plane balancing and for vibration diagnostics. Nikolai is personally involved in customer support, in working through difficult balancing cases and in the development of the software. He works with customers worldwide, in any language.
