Model contact patch geometry, peak pressure, and creepage behavior. Test wheelset scenarios with confidence easily. Turn measured inputs into practical rail interaction insights fast.
The calculator uses a white, single-page layout with a responsive input grid. Large screens show three columns, smaller screens show two, and mobile shows one.
This calculator uses a simplified Hertzian elliptical contact model for normal pressure and a traction-limited stiffness estimate for creepage forces. It is useful for screening studies, comparisons, and maintenance planning.
| Step | Formula | Meaning |
|---|---|---|
| Effective load | W = Wstatic × dynamic factor |
Converts static wheel load into a screened operating load. |
| Equivalent modulus | 1/E' = (1-νw²)/Ew + (1-νr²)/Er |
Combines wheel and rail elastic response. |
| Equivalent radii | 1/Rx = 1/Rw,x + 1/Rr,x1/Ry = 1/Rw,y + 1/Rr,y |
Combines curvature in rolling and transverse directions. |
| Contact ellipse | a ≈ [(3WRx)/(4E')]^(1/3)b ≈ [(3WRy)/(4E')]^(1/3) |
Approximates Hertzian semi-axes of the contact patch. |
| Contact area | A = πab |
Gives the ellipse area. |
| Pressures | pmean = W/Ap0 = 3W / (2πab) |
Returns mean and peak contact pressure. |
| Tangential force | Q ≈ min(μW, Kξ) |
Limits creepage demand by available traction. |
| Wear power | Pwear = Q × v × √(ξx² + ξy²) |
Estimates slip energy rate at the contact. |
| Safety factor | SF = allowable stress / peak pressure |
Shows screening margin against the chosen limit. |
Because true wheel and rail geometry is highly profile dependent, field validation and specialist simulation are still required for certification decisions.
This sample case uses the default values loaded into the calculator.
| Static Load (kN) | Dynamic Factor | Wheel Radius (mm) | Wheel Profile Radius (mm) | Rail Long Radius (mm) | Rail Crown Radius (mm) | Peak Pressure (MPa) | Patch Size (mm) | Resultant Force (kN) | Wear Power (kW) | Safety Factor |
|---|---|---|---|---|---|---|---|---|---|---|
| 90.000 | 1.150 | 460.000 | 330.000 | 300,000.000 | 300.000 | 1,545.908 | 13.521 × 9.457 | 36.225 | 3.439 | 0.906 |
It estimates wheel rail contact patch dimensions, mean and peak pressure, tangential force demand, slip velocity, wear power, and a simple screening safety factor.
No. It is a screening calculator. Profile-specific geometry, plasticity, thermal effects, contamination, suspension dynamics, and track irregularities still need detailed specialist analysis.
Contact curvature differs along rolling and transverse directions. Using two equivalent radii helps approximate an elliptical contact patch instead of a purely circular one.
Creepage is a small relative slip between wheel and rail caused by traction, steering, or lateral motion. It drives tangential forces and wear energy.
Use an engineering limit aligned with your material grade, maintenance standard, and project method. Many teams use internal limits tied to shakedown or allowable fatigue practice.
Wear power is a slip-energy screening metric. Higher values usually suggest more severe rubbing conditions and potentially faster surface damage progression.
Contact area grows nonlinearly with load, modulus, and curvature. Small geometry or load changes can significantly shift peak pressure and margin.
It can support early comparison studies, but flange contact often involves stronger geometry effects and should be checked with dedicated contact models.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.