Using a steam system requires not only ensuring steam is working properly but also managing the bi-product of that steam creation, steam condensate. If not safely removed, steam condensate can cause water hammer, and damage your piping and valves.
What is a steam trap?
An automatic valve that removes condensate from a steam system without wasting steam.
Choosing the right steam trap can be challenging, as there is no one-size-fits-all solution. Whether you are looking for new steam equipment or replacing an old trap model, selecting the right steam trap is necessary to prevent damage to your piping and time-consuming future maintenance.
The right steam trap will save energy and discharge condensate quickly from your system. The best steam trap for your operations will depend on the construction and operation principles that guide your steam system.
Three types of steam traps: mechanical, thermodynamic, and thermostatic
MECHANICAL STEAM TRAP
FREE FLOAT® STEAM TRAP
- First choice for steam-using equipment, steam distribution lines, and high-temperature tracing applications.
- Offers protection from external factors such as wind and rain.
- FF prevents condensate build-up and reduces the risk of water hammer in the steam distribution line.
- Highly energy efficient as a constant water seal covers the discharge orifice, preventing steam from leaving the trap body.
- Increased operating efficiency. Steam traps enable steam to contact the entire heat transfer surface area.
- Significantly reduced localized valve wear.
INVERTED BUCKET TRAP
- Removes a limited amount of air- the weep hole prevents significant steam loss but not air loss, which can hinder system startup or heat transfer on equipment.
- Responds slower than the Free Float®.
- Must maintain a suitable water seal at the bucket bottom to prevent freezing damage.
THERMODYNAMIC DISC STEAM TRAP
- Compact and suitable for a wide pressure range, ideal for a wide variety of tracing, drip, and specific light stream process applications.
- Commonly used for extreme high-pressure steam mains drainage service. Discs can be used at a pressure level of up to 26MPaG.
- Highly resistant to damage from freezing.
- Sensitive to environmental conditions. Rain and cold air can lead to no load actuation.
THERMOSTATIC STEAM TRAPS
BI-METAL, BALANCED PRESSURE, AND EXPANSION THERMOPLASTIC TRAPS
- Commonly used as air vents in steam systems.
- High operational efficiency.
- Helpful conserving energy in tracer lines.
- Reduced discharge temperature by sub-cooling and backing up condensate into the line preceding the trap.
How does a stream trap work?
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Mechanical traps change position in the presence of condensate.
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Thermostatic traps change position when they reach a set temperature.
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Thermodynamic traps operate based off Bernoulli’s principle: Steam vapor holds a disc shut. When those vapors condense, they exert less force and the disc can open.
“How do I know if my steam trap is bad?”
These are 3 tell-tale signs of a bad steam trap
- Pressure buildup in the condensate return line (also causes higher temp) indicates a trap has failed open.
- Water hammer in the condensate return line indicates a trap has failed open.
- A cold trap indicates a trap has failed closed, backing up condensate in steam lines or equipment and leading to inefficiencies or water hammer.
How to test your steam trap
Traps are tested via ultrasonic signature and temperature checks. The TLV trapman system can automatically categorize tested traps and quantify leakage rates using these parameters.
Steam traps are essential for your applications, and there are many options to choose from to meet your needs.
Contact an MCE specialist to help you discover which steam trap works best for you.