ToolJoltTools

Stress Concentration Factor Calculator (Hole)

Kt for a circular hole in a finite-width plate under tension (Howland).

0
K_t (on net section)
0
Peak stress at hole edge (MPa)

An infinite plate gives the famous Kt = 3. Fatigue cracks are born at these peaks โ€” which is why every failure investigation starts at a hole, keyway or fillet.

Formula

K_t = 3 โˆ’ 3.14(d/W) + 3.667(d/W)ยฒ โˆ’ 1.527(d/W)ยณ (Howland fit)
References: Peterson's Stress Concentration Factors

Stress Concentration Factor Calculator (Hole) is a free stress concentration for design engineers, metallurgists and QA inspectors โ€” instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.

About Stress Concentration Factor Calculator (Hole)

Kt for a circular hole in a finite-width plate under tension (Howland). The calculation implements K_t = 3 โˆ’ 3.14(d/W) + 3.667(d/W)ยฒ โˆ’ 1.527(d/W)ยณ (Howland fit) (Peterson's Stress Concentration Factors). An infinite plate gives the famous Kt = 3. Fatigue cracks are born at these peaks โ€” which is why every failure investigation starts at a hole, keyway or fillet.

How to use Stress Concentration Factor Calculator (Hole)

  1. 1Enter Hole diameter in mm.
  2. 2Enter Plate width in mm.
  3. 3Enter Nominal (gross) stress in MPa.
  4. 4Read K_t (on net section), Peak stress at hole edge instantly โ€” no submit button needed.
  5. 5Need US units? Flip the SI/Imperial toggle and every field converts.

Why use Stress Concentration Factor Calculator (Hole)?

  • โœ“Implements the standard formula โ€” K_t = 3 โˆ’ 3.14(d/W) + 3.667(d/W)ยฒ โˆ’ 1.527(d/W)ยณ (Howland fit)
  • โœ“Reference cited on-page: Peterson's Stress Concentration Factors
  • โœ“One-click SI โ‡„ Imperial toggle โ€” values convert in place, physics stays in SI
  • โœ“Live worked example: the substitution recomputes from your numbers
  • โœ“Runs entirely in your browser โ€” nothing uploaded, free forever

Frequently asked questions

What formula does the Stress Concentration Factor Calculator (Hole) use?+

It computes K_t = 3 โˆ’ 3.14(d/W) + 3.667(d/W)ยฒ โˆ’ 1.527(d/W)ยณ (Howland fit), per Peterson's Stress Concentration Factors. The formula is displayed under the result along with a worked example substituted with your own inputs.

What should I keep in mind when using this calculator?+

An infinite plate gives the famous Kt = 3. Fatigue cracks are born at these peaks โ€” which is why every failure investigation starts at a hole, keyway or fillet.

Where do the material property defaults come from?+

Defaults are standard handbook values (ASM, manufacturer datasheets, the cited standard). Always substitute certified values from your material's test certificate for critical work.

Is the Stress Concentration Factor Calculator (Hole) free to use?+

Yes โ€” completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.

Related tools

Related Engineering tools

Sponsored