Free Engineering Tool
Steel Properties & Allowable Stress Calculator
Select a steel grade to view mechanical properties. Calculates ASME allowable stress, fatigue endurance limit, and safety factors for different load types.
Properties & Allowable Stress
ASME Allowable Stress
Per ASME BPVC Section VIII Division 1, the allowable stress at room temperature is:
For austenitic stainless steels (which have significant work hardening), ASME uses Rm/2.4 instead of Rm/3.5.
Fatigue Endurance Limit
For unnotched, polished steel specimens under rotating bending:
Actual fatigue strength requires modification factors for surface finish (ka), size (kb), reliability (kc), etc.:
Safety Factors by Load Type
| Load Type | Factor n | Design Stress |
|---|---|---|
| Static (yield) | 1.5 | Rp0.2 / 1.5 |
| Static (fracture) | 2.4–3.5 | Rm / 2.4 or Rm / 3.5 |
| Pulsating fatigue | 2.0 | Se / 2.0 |
| Fully reversed fatigue | 2.5 | Se / 2.5 |
| Impact / shock | 3.0–5.0 | Rp0.2 / n |
Practical Example
Properties: Rp0.2 = 900 MPa, Rm = 1100 MPa
σ_allow (ASME) = min(900/1.5, 1100/3.5) = min(600, 314) = 314 MPa
Se = 0.5 × 1100 = 550 MPa (unmodified)
Pulsating fatigue: 550/2.0 = 275 MPa
⚠️ Note: Properties shown are typical values. Actual properties depend on heat treatment, section size, and material test certificate. Always use certified values for design calculations.
The procedures described on this page were developed and field-tested by the Vibromera team using the Balanset-1A, a portable dual-channel balancer and vibration analyzer for on-site rotor balancing.
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.
