Steam Theory 1. Basics of Steam What is Steam? Principal Applications for Steam Types of Steam Flash Steam How to Read a Steam Table 2. Steam Heating Heating with Steam Steam Heating Mechanism Overall Heat Transfer Coefficient What is Vacuum Steam? Tracing the Causes of Heat Maintenance Issues 3. Basics of Steam Traps What is a Steam Trap? The History of Steam Traps #1 The History of Steam Traps #2 How Mechanical Traps Work: A Look at their Mechanism and Merits How Disc Traps Work: A Look at their Mechanism and Merits How Bimetal-Type Thermostatic Steam Traps Work: A Look at their Mechanisms and Merits 4. Steam Trap Selection Steam Trap Selection: How Application Affects Selection Steam Trap Selection: Understanding Specifications Steam Trap Selection: Safety Factor and Life Cycle Cost Traps and Orifices Part 1 Traps and Orifices Part 2 Casting vs. Forging Applications of Different Types of Steam Traps Don't Get Steamed : Selecting Steam Trap Design Understanding Steam Traps Compare Two Fixed Orifice Venturi Products to a Variable Orifice Free Float Steam Trap 5. Steam Trap Problems Is My Trap Leaking Live Steam? Temperature Control Trap Precautions Trap Installation Orientation Trap Back Pressure Double Trapping Group Trapping Steam Locking Air Binding My Steam Trap Is Good - Why Doesn't It Work? 6. Steam Trap Management Introduction to Steam Trap Management Steam Trap Losses - what it costs you A Guide to Steam Trap Testing Implement a Sustainable Steam Trap Management Program Impact Plant Performance by Improving the Steam System 7. Water Hammer Water Hammer: What is it? Water Hammer: The Mechanism Water Hammer: Cause and Location Water Hammer: In Steam Distribution Lines Water Hammer: In Equipment Water Hammer: In Condensate Transport Piping Identifying Water Hammer Using a Thermal Camera Mitigation of Water Hammer in Vertical Flashing Condensate Transport Piping Stop Knocking Your Condensate Return Steam Trap Management: Do Something; Anything. Please! 8. Risk Mitigation Steam System Optimization and Risk Mitigation Risk Based Methodology for Industrial Steam Systems Why Bad Things Happen to Good Steam Equipment Beware of the Dangers of Cold Traps Steam System Winterization: How to Protect Your Plant 9. Steam Quality Wet Steam vs. Dry Steam: The Importance of the Steam Dryness Fraction Separators and their Role in the Steam System Clean & Pure Steam Temperature Problems Caused by Air Removing Air from Steam Equipment Air Vents for Steam Steam Quality Considerations 10. Steam Distribution Best Practices for Condensate Removal on Steam Lines Installation Tips for Steam Traps on Steam Mains Erosion in Steam and Condensate Piping Corrosion in Steam and Condensate Piping Allocate New Plant Focus to Steam System Design—Part 1 11. Condensate Recovery Introduction to Condensate Recovery Returning Condensate and When to Use Condensate Pumps Condensate Recovery: Vented vs. Pressurized Systems Condensate Recovery Piping What is Stall? Methods of Preventing Stall Cavitation in Condensate Pumps Steam Heat Exchangers are Underworked and Over-Surfaced Allocate New Plant Focus to Steam System Design—Part 2 Optimize Reboiler Performance via Effective Condensate Drainage Vent Away Condensate Pump Frustrations in a Flash 12. Energy Efficiency Tips to improve steam plant efficiency Advice on Winter Preparation for Steam Systems Insulating Traps Steam Compressors Why Save Energy? Management Strategies for Conserving Energy Recovering Steam Clouds and Waste Heat Waste Heat Recovery Boiler Energy Saving Tips Steam Line Energy Saving Tips Steam-Using Equipment Energy Saving Tips Preventing Steam Leaks Handle Steam More Intelligently Optimize the Entire Steam System Use Available Data to Lower System Cost 13. Compressed Air / Gas Removing Condensate from Compressed Air Preventing Clogging of Air Traps Air Compressor Energy Saving Tips Improving Compressed Air Quality and Countermeasures Against Leaks 14. Other Valves Types of Manual Valves Bypass Valves Check Valve Installation and Benefits Pressure Reducing Valves for Steam Traps and Orifices Part 2 Contents: The discussion on orifices in Traps and Orifices Part 1 focused on why the diameter of a trap orifice (valve seat) is much smaller than the diameter of the connected piping. In Part 2, we will discuss the significance of the trap orifice number. What is an Orifice No.? The higher the trap orifice number, the smaller the diameter of the orifice. At first glance, this may seem counter-intuitive, but a closer look reveals the reasoning behind this system. In TLV steam traps, the orifice number indicates the maximum differential pressure in kg/cm² (bar) at which the steam trap will discharge condensate. For example, a No. 10 orifice is rated for 10 kg/cm² (10 bar, 150 psi). The higher this number is, the higher the pressure at which the orifice can be used to drive condensate through it. However, in order to achieve higher operating pressure differentials, a smaller opening is required, which results in a lower discharge capacity for a given operating differential pressure. Forces Acting to Close and Open the Valve When we think about the size of an orifice, we must consider two of the forces at work inside the Free Float® trap, namely the force that acts to open the valve and the force that acts to close the valve. The mechanism that causes the Free Float® trap to operate is the force of buoyancy.Buoyancy causes the float (which is also the valve itself) to rise, and after the float rises up off the valve seat, the valve is in the open position. In other words, the force of buoyancy is the force that acts to open the valve. If we assume that the specific weight of condensate is a constant, then the buoyancy of the float is determined by the volume of the submerged part of the float. The force of buoyancy is therefore at its highest value when the float is completely submerged, and given that the same float is being used, it is not possible to achieve a stronger force acting to open the valve than this. In contrast, the force acting to close the valve is a force that is created by the diameter of the orifice and the difference between the pressures in front of and behind the orifice. An example of this that is familiar to many of us is when the water is draining out of a bathtub that uses a drain plug. If the plug gets too close to the drain as water is being drained out, the plug is sometimes sucked back into place on the drain, closing off the flow of water. A force identical to this is at play inside a Free Float® trap.The force is represented as pressure differential x surface area, so if the orifice diameter is a constant, then the larger the difference in pressures in front of and behind the orifice (the differential pressure), the stronger the force acting to close the valve. Conversely, if the differential pressure is fixed, then the larger the orifice diameter, the stronger the force acting to close the valve. Fig. 1 If the orifice diameter is constant, then the larger the operating differential pressure, the stronger the force acting to close the valve. Fig. 2 If the differential pressure is constant, then the larger the orifice diameter, the stronger the force acting to close the valve. Orifice No. Selection While the force acting to open the valve has a maximum value (determined by the size of the float), the force acting to close the valve can vary depending on the operating pressure. Condensate cannot be evacuated if this force is too great, which can cause the valve to remain in the closed position. In order to overcome this limitation imposed by the operating pressure, a variety of orifice no.’s are offered for use with different maximum operating pressures. Summary Objective To Increase the Discharge Capacity To Increase the Maximum Operating Pressure Method Increase the orifice diameter (smaller orifice number) Decrease the orifice diameter (larger orifice number) Consequence Reduced maximum operating pressure Reduced discharge capacity In short, even for the same trap model, there are selection options to be made between maximum operating differential pressure and discharge capacity. Reducing the maximum operating pressure allows us to achieve a greater discharge capacity at any given differential pressure, while reducing the maximum discharge capacity provides a higher maximum operating pressure. Traps and Orifices Part 1 Casting vs. Forging Also on TLV.com Free Float® Steam Traps for Process Use Free Float® Steam Traps for Steam Mains and Tracer Lines Steam and Condensate Training Seminars Engineering Calculator