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Recent content by Thomasjl

  1. Thomasjl

    Does anyone recognize this P&ID Symbol?

    When I look to the symbol the first thing that comes up is an bellow with 2 rods to avoid overstretching. I agree with JJPellin and JohnGP – Further a few things to consider. Often bellows do appear on P&ID’s as they do effect the flow in the pipe. P&ID’s are also often used for a (bulk)...
  2. Thomasjl

    Selecting materials for piping systems

    Thanks MJC, My position is not that bad, it doesn't occur every day and I am not expected to know everything. I do have other people I can fall back on, but it takes time and efford. But above all: I hate black holes in my knowledge, specially when the answers seems to be within reach. MJC, it...
  3. Thomasjl

    Selecting materials for piping systems

    My position is Mechanical Piping Engineer in the (Bio, Petro) Chemical industry. My skills are running short with determining the composition of materials for piping and its components. For example: you have a pipe transporting a certain medium (sea water or chloride etc.), then my problem is...
  4. Thomasjl

    Use of Expansion Bellows

    Hi there, I presume we talk about a centrifugal pump. A bellow makes the flow turbulent and has possible air traps, one is even worse than the other. The only advantage of bellows is that there are no forces on the pump nozzle, which extends the life time. A proper running centrifugal pump...
  5. Thomasjl

    Welding Slip on Flange to Long Radius Elbow

    Theoretically you need a straight piece of pipe to weld the SO, true, an elbow section is unround and theoretically you can't slide the SO over the elbow. But in practice often you can. Then you don't have the (exact)required root openings but that is not a problem, not in strength and not in...
  6. Thomasjl

    Expansion joints and Anchors for steam distribution.

    No bellows in my piping systems, only piping expansion loops! Only use bellows in the ultimate case that you don't have room for expansion bellows. If you can avoid bellows, avoid it.
  7. Thomasjl

    Working on a flowing oil pipeline

    A bypass arround what? Can you give some more details?
  8. Thomasjl

    Hot Water System Piping Technique

    Pennpoint, This is not regarding a hot water supply system, which is normally soldered, but a heating system. A heating system is both hotter and temperature changes more often. I would not recommend CU piping anyway, but that is not Blutforts question. My concern is regarding the strength or...
  9. Thomasjl

    Hot Water System Piping Technique

    TBP It has nothing to do with the temperature, or at least not directly. It’s the mechanical working of the expansion and contraction that does the damage. I haven’t seen it happen it the field. I am just an engineer who does what a specification says. This spec appears trustworthy to me.
  10. Thomasjl

    Hot Water System Piping Technique

    In time the soft soldering cracks due to the expansion and contraction. Brazing doesn't. Simple as that. Good luck, Thomas
  11. Thomasjl

    BURIED FLANGES STANDAR

    anyan1, An underground flange connection has some disadvantages. The ones I can think off at this moment: 1. When leakage occur nobody notices 2. It acts as an anchor. Long straight underground lines (even for warm or hot service) don't move. Underground lines, for warm or hot service, near an...
  12. Thomasjl

    Static Discharge in Hoses

    Goldenspark Make sure the hose is kept away from any aerating possibility, keep it in the air, put rubber blocks underneath or something. Then the static electricity remains in the liquid until it is drained at the SS joints. Simple as that. Good luck Thomas.
  13. Thomasjl

    Tailings pipeline laing on the ground

    It looks like a very expensive line. How do you maintain the rubber lining at the (welded??) joints? What is the ground look like, sand, gravel, turf, soil??? What are tyhe min and max design temperatures?? What is the required life span? Supporting a heat traced and HDPE outsode line is very...
  14. Thomasjl

    Static Electric Discharge Hazard

    To my opinion this threat is getting very confused because it swerves away from the purpose. When talking about static electricity it is very important that we first distinguish whether we deal with an explosive mixture or not. If we do not deal with a vapour between LEL and UEL (see my threat...
  15. Thomasjl

    Static Electric Discharge Hazard

    MotoGP, As long it is within the liquid hydrocarbons there is nothing to worry about static electricity or any other electricity (e.g. lightning) because it can´t ignite anything. What is combustible is the vapour of your hydrocarbons mixed with a little oxygen, not too much and not too little...

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