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Re: [MW:5062] Piping Category

By Materials & Welding
Dear Dihnesh,
Based  on B31.3, OWNER SPECIFICES THE PIPING SYSTEM,
 Normal—ordinary process piping service
  • Category M—Lethal fluid service
  • High Pressure—Exceeds ASME B16.5 pressure limits for Class 2500 flanges
  • Severe Cyclic—Stress at a joint exceeds 80 percent of the allowable stress range and the number of thermal cycles will exceed 7,000
  • Category D—Innocuous fluid, low-pressure, and not very high-temperature service

    • B 31.3 FLUID SERVICE ,
    Category D: The fluid handled is nonflammable, nontoxic and not damaging to human tissue. The design pressure doen not exceed 150 psig ( 1035 kPa). The Design temperature is greater than -20deg F (-29 dec C) and does not exceed 186deg C. OFTEN CHARACTERIZED AS " UTILITY".
    Category M: A fluid service in which the potential for personnel exposure is judged to be significant and in which a single exposure to a very small quantity of a toxic fluid, caused by leakage, can produce serious irreversible harm to persons upon breathing or on bhodily contact, even when prompt restorative measures are taken. OFTEN CHARACTERIZED AS " LETHAL".
     
    Severe Cyclic conditions: Conditions applying to specific piping components or joints in which Se.... exceeds 0.8 Sa and the equivalent number of cycles exceeds 7000; or conditions which the designer determines will produce and equivalent effect.
    Regards,
    Yadav Shiva Chelliya,
    Inspection Engineer,
    Doha Qatar,
    +974-6166465
     
     
     
    On Tue, May 4, 2010 at 9:35 AM, dhinesh gnanadhas <dhineshlhmm@gmail.com> wrote:
    Hi

    Based on Which criteria the Piping services are being categorised as
    Category 'D',  'M', Normal & Sevier Cyclic fluid?

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