Calculator
Steam Trap Sizing Calculator
Calculate the required steam trap capacity and orifice size based on condensate load, safety factor, and differential pressure. Select the right steam trap for your application.
Interactive toolUpdated July 2026
Inputs
Calculated from the heat duty
Typical: 2× for F&T, 3× for thermodynamic
Condensate return line pressure
Results
Required Capacity
1,000 kg/hr
Condensate load × safety factor
Differential Pressure
9 bar
Inlet − outlet pressure
Estimated Orifice Diameter
0.1 mm
For sizing reference
Sizing Principles
- The safety factor accounts for startup conditions — condensate load is much higher when the system is cold
- Float & Thermostatic traps: use 2× safety factor
- Thermodynamic (disc) traps: use 3× safety factor
- Inverted bucket traps: use 2–3× safety factor
- Thermostatic traps: use 2–3× safety factor
- Select a trap with a rated capacity at least equal to the required capacity at the operating differential pressure
- Never oversize by more than 3× — oversized traps short-cycle and wear faster
Calculating Condensate Load
The condensate load depends on the heat duty of the equipment:
Condensate (kg/hr) = Heat Duty (kW) / Latent Heat (kJ/kg) × 3600
At 10 bar(g), latent heat is approximately 2,000 kJ/kg. So a 500 kW heat exchanger produces approximately 900 kg/hr of condensate.