Analyze gasket compression, seating load, and sealing readiness. Switch units, losses, and bolt inputs easily. Visualize actual versus required stress before final assembly checks.
Use this sample set to test the calculator and compare trends before entering field values.
| Parameter | Example Value | Notes |
|---|---|---|
| Unit system | Metric | Lengths in mm, pressures in MPa, loads in kN. |
| Outer diameter | 180 mm | Outer contact boundary of the gasket ring. |
| Inner diameter | 140 mm | Inner contact boundary near the flow path. |
| Seating stress y | 68.9 MPa | Minimum assembly stress needed to seat the gasket. |
| Gasket factor m | 3.0 | Represents the pressure-retention demand in service. |
| Pressure | 2.5 MPa | Internal operating pressure across the joint. |
| Bolt preload | 8 bolts × 45 kN | Primary clamping force before service losses. |
| Load loss | 12% | Models relaxation, embedment, and thermal effects. |
This calculator uses a practical flange-joint screening model centered on contact area, assembly compression, and service retention.
Radial Width, w = (Do − Di) / 2 Effective Width, b = w × Width Factor Mean Diameter, G = (Do + Di) / 2 Contact Area, A = π × G × b Initial Bolt Load, Wi = (Number of Bolts × Preload per Bolt) + Additional Load Residual Bolt Load, Wr = Wi × (1 − Load Loss % / 100) Required Seating Stress = y × Safety Factor Required Seating Load, Wseat = A × Required Seating Stress Actual Seating Stress, qactual = Wi / A Hydrostatic End Force, H = P × π × G² / 4 Required Operating Load, Wop = (P × π × b × G × m) + H Operating Reserve Factor = Residual Bolt Load / Required Operating LoadThese equations provide a useful engineering estimate. Final flange, bolt, and gasket verification should still follow the governing design code and material data.
Gasket seating stress is the compressive contact stress needed during assembly so the gasket conforms to flange surfaces and forms an initial seal.
Bolt preload supplies the compression that creates gasket contact pressure. If preload is too low, the joint may leak before or during operation.
The y value is the minimum gasket seating stress required to seat the gasket properly under assembly conditions. It usually comes from gasket data.
The m factor estimates how much additional gasket load is needed to maintain sealing while internal pressure tries to separate the joint.
Preload can drop because of embedment, creep, gasket relaxation, and thermal cycling. Modeling loss helps judge whether sealing force remains after startup.
It is the ratio of residual bolt load to required operating load. Values above one suggest the remaining clamp load exceeds the estimated service demand.
No. It is best for screening, comparisons, and early design checks. Final decisions should use the applicable flange design code and manufacturer data.
Yes. Adjust the effective width factor below 1.0 when only part of the radial width is expected to carry contact stress.
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.