As we know steam is vapor form of water produced by adding heat energy. As steam is form of water only it tends to condensate when energy is removed, Heat loss can be formed due to various factors like environment, process use etc. In this article let us discuss about what is steam trap ? Purpose, types and usage.

What is Steam trap?
Steam traps is most common steam equipment installed in steam system used to discharge condensate, air and other incondensable gases from steam system without letting live steam to vent out. A steam trap is a mechanical device used in steam systems to remove condensate (the liquid formed when steam cools down) while preventing the loss of valuable steam. It plays a crucial role in maintaining the efficiency and functionality of steam systems in various industrial processes, heating systems, and steam-powered equipment.
The primary function of a steam trap is to allow condensate to be discharged from the steam system while blocking the passage of steam. Since steam carries a significant amount of heat energy, any loss of steam can lead to energy wastage and reduced system efficiency. Steam traps help conserve energy by ensuring that only condensate is removed, while steam is retained within the system.
Why it is important
Steam trap is important for smooth, efficient and smooth operation of steam system.
The importance of steam traps lies in their ability to:
- Energy Conservation: Steam traps help conserve energy by ensuring that only condensate is removed from the steam system, while retaining the valuable steam. If steam were to escape, it would lead to energy wastage and increased fuel consumption.
- Cost Savings: Effective steam traps prevent steam from being wasted, which directly translates into cost savings for industries. By efficiently removing condensate, steam traps contribute to lower fuel and water consumption.
- Process Efficiency: Properly functioning steam traps maintain the desired temperature and pressure in the steam system, which is crucial for the efficient operation of various industrial processes. Consistent steam supply enhances process productivity and reduces production downtime.
- Equipment Longevity: Steam traps prevent condensate from accumulating in steam-powered equipment. If condensate were to collect, it could lead to water hammer, corrosion, and other damage, reducing the lifespan of the equipment.
- Safety and Reliability: Steam traps contribute to a safe working environment by preventing the buildup of condensate, which can cause uneven heating and potentially hazardous conditions. They help ensure the reliability of steam systems and equipment.
- Quality of Steam: Steam traps help maintain the quality of steam by removing impurities and ensuring that only dry steam is delivered to the desired locations. Dry steam is essential for many industrial processes, as wet steam can lead to operational issues and reduced product quality.
- Regulate System Pressure: Steam traps assist in maintaining the appropriate pressure levels in the steam system. They help prevent pressure fluctuations and ensure that the system operates within the desired pressure range.
- Process Control: Steam traps aid in maintaining process control by regulating steam flow and removing condensate in a controlled manner.
Types of Steam Trap
Steam traps can be classified based on various factors, including their operating principle, design, and application.
The main types of steam traps are:
- Mechanical Steam Traps:
- Float Steam Trap: Utilizes a float that rises with the accumulation of condensate, opening the valve to discharge the condensate. When steam enters, the float sinks, closing the valve.
- Inverted Bucket Steam Trap: Uses an inverted bucket that floats on the condensate. When the bucket is full, it rises and opens the valve to discharge the condensate. When steam enters, the bucket sinks, closing the valve.
- Thermostatic Steam Traps:
- Bi-Metallic Steam Trap: Employs two dissimilar metals with different thermal expansion rates. When heated, the metals expand at different rates, causing the trap’s valve to open and discharge condensate. As the trap cools, the metals contract, closing the valve.
- Thermostatic Steam Trap: Operates based on temperature changes with a thermostatic element, like a bimetallic strip or an expansion element. It opens when condensate is present and closes when steam is present.
- Thermodynamic Steam Traps:
- Disc Steam Trap: Uses the principle of fluid dynamics to open and close the valve. Steam flows create a pressure drop that lifts the disc, allowing condensate to be discharged. When condensate fills the trap, the pressure equalizes, and the disc closes the valve.
- Compound Steam Traps:
- Float and Thermostatic (F&T) Steam Trap: Combines the functions of a float mechanism and a thermostatic element. The float rises with condensate accumulation, opening the valve. The thermostatic element ensures that the trap remains closed when steam is present.
- Bellows Steam Traps:
- Bellows Steam Trap: Uses a bellows element that expands and contracts with changes in temperature. When condensate is present, the bellows expands and opens the valve to discharge condensate. When steam enters, the bellows contracts, closing the valve.
- Orifice Steam Traps:
- Orifice Steam Trap: Utilizes an orifice plate to modulate the flow of condensate and steam. The orifice restricts the flow of steam, allowing condensate to be discharged at a controlled rate.
For understanding Stall in steam lines click here