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Clear steam traps/piping

Kev7s Member Posts: 1
I started teaching steam systems / steam systems maintenance, at are local. Are union just finished building new service training center. I would love to set up a steam system, with clear traps and piping so the apprentices can see how the the different traps operate. I know Armstrong and Spirax-Sarco mush have something like this, in there training centers due to the videos, I have seen on you tube. My question is how are they doing it very low pressure, Vacuum or gravity. Also would like to know what materiel they used glass, or Lexan. Is there any manufactures that my make clear traps. Thanks for any help.


  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 1,805
    edited August 2020
    The only clear steam system I'm familiar with is the one that Weil McLain used to truck around to trade shows.
    Not so much on how the emitters or traps work in this video. The steam is vented to the atmosphere.
    Edward Young
    Retired HVAC Contractor from So. Jersey Shore.
    Cleaned & services first oil heating system at age 16
    Specialized in Oil Heat and Hydronics where the competition did Gas Warm Air

    If you make an expensive repair and the same problem happens, What will you check next?
  • mattmia2
    mattmia2 Member Posts: 2,654
    You could potentially fit like a 5-10 gallon 120v water heater with steam trim, gauge glass, vaporstat, pressure relief valve, lwco and use it as a steam source for a small radiator. Getting a trap molded in plastic would be difficult, but you could use clear plastic or glass piping before and after the trap and the inlet so you could see what was going on. Could probably even find a clear tubing that would not soften at steam temps. It just needs to maintain its structure, it doesn't necessarily be code approved.

    You could maybe even scale it down mush smaller with maybe an electric kettle controlled with a microcontroller or similar.
    EBEBRATT-Ed Member Posts: 8,522
    I bet McMaster Carr would be a good source for some type of clear piping.

    You might make a few calls to some of the trap manufacturers. They would probably help you out with training equipment/ideas. Maybe @Sailah will comment or point you in the right direction
  • mattmia2
    mattmia2 Member Posts: 2,654
    I found some tubing that technically only had a rating up to 170, but probably would still stay relatively rigid at 212-220 or so at mcmaster-carr
  • Larry Weingarten
    Larry Weingarten Member Posts: 2,083
    Hi, Any way to run this at partial vacuum, to reduce the boiling point? Harder to melt plastics then :p

    Yours, Larry
  • izhadano
    izhadano Member Posts: 84
    Hello, Kev7s
    I was crazy enough to connect radiators in my house vacuum steam system to boiler by transparent plastic tubing, - Dan Holohan kindly described my endeavor in his article for PM Magazine.
    Actually, the main and branches were 3/4 copper tubing, rizers - 5/8" ID Teflon tubing  and return lines -high density 1/2" ID polypropylene (I boiled them for 1 hour to be sure that it's safe). Works fine. Used compression fittings/adapters  to connect copper to  plastic tubing. It's safer to use inserts on plastic tubing - otherwise leaks can develop with time.
    Polysulfone would be optimal material for future steam/vacuum plumbing - it's very strong plastic, already approved for use in low pressure steam up to 200C. transparent (amber colored).
    This is a picture of polysulfone supply line into radiator. 1"OD polusulfone tube is connected to metal pipe via clamped silicone sleeve . Works 4th season without any problems.

    BTW, silicone tubing might be a good choice as well - transparent, very good for high temperature steam, but not rigid at elevated temperatures.

    Making steam trap body of plastic to get complete transparency would be too expensive, but using transparent plastic tubing on steam trap entrance and exit would be very eye- opening. If you add infrared camera to visualize heat distribution, the picture would be complete.  

    Hope that will help. Please, let me know if you may have more questions.
  • retiredguy
    retiredguy Member Posts: 350
    edited August 2020
    You could contact "Ace Glass inc "at 800-223-4524 or just "GOOGLE" Ace Glass inc and check out what they have. Also, they have a web site ( The glass that you are looking for is called something like Boro Silicate
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