The Thermo-Dynamic Traps is designed to hold up against water hammer, condensate that usually corrodes a trap and it keep the system from freezing in cold winter months. When your application calls for condensate removal from the steam systems, the thermo-dynamic trap is the first choice. They come in a variety of sizes ranging from 3/8 inches and 1 inch. They can hold up to 4,700 pounds of pressure and they are constructed of carbon steel, stainless steel and alloy steel. One of the Thermo-Dynamic Steam Traps is model BDT52L. These are constructed with 316L stainless steel and they come in 3 sizes, 1/4″, 3/8 and 1/2″ inches. They operate under a minimum operating pressure (PMO) of 3.5 psi and a maximum of 150 psig. The maximum operating temperature of these traps are 850 degrees Fahrenheit. These traps can operate under a PMA, max pressure of 230 psig and 0-850 degrees.
They are a good choice for a more powerful and more aggressive systems. The most common commercial applications for this style trap are chemical industries, the food and beverage industry and for WFI Systems. There are 3 main components for a Spirax Sarco Thermo-Dynamic Steam Trap. They are the body, the cap and the disc. They are all made in stainless steel for the BDT52L trap. There is an option to purchase a Insulcap, this cap is a chafing fit cover design that will help lower the effects of extreme heat loss that may the result from low temperatures or weather elements such as wind or rain. These traps have an install instruction that is simple once you get the hang of it. These traps are horizontal traps, meaning they are installed closely to the pipes or the system that they are being used on. If these traps are being used to prevent freezing or for self-draining systems, they can be installed vertically. You will need an NPT 0.065″ O.D Tubing used with 1/2″ inch traps only and they are Tri Clamp friendly but only in 1/2″ inch traps.
Maintenance on these traps can be performed without interrupting the flow of the system. You can perform the trap isolating from the supply and return lines. Then take apart the trap and remove any debris in the trap. Then reinstall and secure properly. To prevent total trap shutdown, where the traps have top be replaced, maintenance should be done every three months or so. Some other Spirax Sarco Thermo-Dynamic Steam Traps Models are the TD120, TD42, TD45, TD52, TD62 and the TDC. You can purchase these traps through your local heating product shop or through a HVAC location. Use the traps that are best designed for your systems. If you have any questions, ask your local HVAC expert.
Thanks for your kind discription of steam traps.
I have a question about disposal of steam condensate after trapping.
In case of a thermo-dynamic steam trap and steam pressure of 2kgf/cm2, how highly(m) can it lift up condensate vertically to the return line ?
Basecally, the return line of steam condensate should be located above the trap and heat exchangers.
Reply to Steam Kim
Every 28 inches (.71 meters) of vertical height creates 1 psi of back pressure (.0703 kg/cm2). With 2kg/cm2 (28.44 psi) you could theoretically lift 19.88 meters (65.65 ft). That would leave no differential across the trap and would not be realistic. The back tolerance of that type is 80 % of the inlet pressure but I would never recomend more than 50 % back pressure. So in your case the lift should never exceed 9.94 meters (32.30 ft). It is never good the have the return line above the trap especially on heat exchangers and process equipment where a modulating control valve will throttle the steam to control temperature as the pressure can drop to zero when the steam demand drops. Heat exchange equipment never has a guaranteed pressure after the control. Gravity drainage is always best.