Steam Trap Selection Guide

Steam Trap Technology Overview by Application

This guide outlines the suitability of different steam trap technologies for various industrial applications. Blue cells in the original document indicated suitability.

• INSTRUMENT STEAM TRACING: Primarily suited for Thermodynamic traps.
• LINE STEAM TRACING: Suitable for Thermodynamic traps.
  • High Temperature: Condensate discharged as soon as it forms.
  • Low Temperature: Sub-cooled condensate discharged.
• MAIN STEAM SUPPLY LINES (DRIP): Suitable for Thermodynamic and some Thermostatic traps, covering various pressure ranges (High: >600 psi, Medium: 300-600 psi, Low: up to 300 psi).
• PROCESS STEAM EQUIPMENT: Suitable for both Thermodynamic and Thermostatic traps across diverse applications such as Sterilizer Drainage, Lift and Syphon Drainage, Autoclave Drainage, Platen Presses and Calenders Drainage, Variable Flow and Heat Exchangers, and Gravity Drainage (kettles, double jacket).
• TURBINES DRAINAGE: Suitable for both Thermodynamic and Thermostatic traps for Upstream (supply) and Downstream (drain) applications.
• AIR VENT: Primarily suited for Thermostatic traps.

For detailed model specifications and suitability, please refer to the 'Steam Trap Overview: Model Details' section below.

Sizing Parameters and Flow Rate Estimation

Proper steam trap selection requires understanding key sizing parameters:

• Operating inlet pressure
• Operating outlet pressure or back pressure
• Differential pressure (inlet pressure minus outlet pressure)
• Required condensate flow capacity (if unknown, estimation methods are provided)

Once these parameters are determined, specific trap models can be selected from product bulletins.

Estimation of Flow Rates for Various Applications (Rule-of-thumb estimates)

1. Instrument Steam Tracing

Flow rate typically does not exceed 60 lb/hr.

[Description: Schematic illustrating a steam line connected to a steam trap for instrument tracing.]

2. Line Steam Tracing

Flow rate typically does not exceed 100 lb/hr.

[Description: Schematic showing a steam line with a steam trap for line tracing, similar to instrument tracing but for longer runs.]

3. Main Steam Supply Line

Condensate flow rates for a properly insulated line are estimated in the table below:

Insulated Steam Mains Condensate Load per 100 Ft. Sch. 40 Pipe

Note: Table values are based on 70°F ambient temperature and 85% insulation efficiency. For 0°F ambient, multiply values by 1.5.

4. Steam Trapping for Turbines

Turbine steam is typically superheated, meaning condensate formation is minimal. Selection is based on operating pressure and superheat degree, with traps acting as safety devices during startup/shutdown.

[Description: Schematic showing a turbine steam inlet protected by a steam trap.]

5. Steam Trapping for Process Equipment

For unknown flow rates, estimate condensate flow using the heating apparatus's calorific power (BTU/hr) with the formula:

Condensate Flow (lb/hr) = BTU Rating (in millions) / 100

[Description: Schematic illustrating a process vessel with a steam trap for condensate removal from the steam inlet.]

Steam Trap Overview: Model Details

Thermodynamic Traps

Thermostatic Traps

Connection Types:

• T = Threaded
• F = Flanged
• SW = Socketweld