Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Recent content by sanshu1111

  1. sanshu1111

    Embrittlement of Duplex Stainless Steel (UNS 31803)

    Thanks for all your responses. Any idea about ASME Sec VIII Div 2 limit of 204 Deg C for UNS 31803 whereas limits in Div 1 and B31.3 are 316 Deg C. With best wishes for Christmas and a Very happy New Year.
  2. sanshu1111

    Embrittlement of Duplex Stainless Steel (UNS 31803)

    Impact values reported in MTC are in the range of 150 joule, is it possible to get so high values with no or incorrect heat treatment of flanges? Normal operating temperature for the heating cycle (heating cycle time duration is appx 1/ 4 of total cycle time) is appx 250 - 255 Deg C and there...
  3. sanshu1111

    Embrittlement of Duplex Stainless Steel (UNS 31803)

    One of our facility is operating under thermal cycle with temperature raging from 60 Dec C to 260 Dec C. After operating it for appx 5 years, we found some cracks on our piping system (flange and flange to elbow weld joint/ HAZ) which is in DSS UNS 31803 construction. We send this piping...
  4. sanshu1111

    Nozzle Reinforcement

    Terms RF pad and doubler plate are commonly used with same meaning. RF pad is however to provide reinforcement to any opening or a load bearing component where existing shell/ head thisckness is not sufficient. Double plate on the other hand is just a barrier/ pad plate which is of the same...
  5. sanshu1111

    Pass partition weld for Plug header type air cooler as per ISO 13705

    Dear JTE/ Duwe6, Thanks for your response. Yes this requirement is not properly written in ISO/ API and is leading to confusion. I wanted to check if I am missing any thing on this requirement. JTE, API 661/ ISO 13705 require full penetration weld for the stay plates and for partition plate if...
  6. sanshu1111

    Pass partition weld for Plug header type air cooler as per ISO 13705

    Not sure if I am reading it correctly as to why a full penetration weld joint preparation is required for the seal weld? In addition, seal weld from both the sides will not be possible if the air cooler is multi pass with more than one pass partition plates on the header or have stiffener...
  7. sanshu1111

    Use of Low Temp Carbon Steel piping material for 4500 kPa Super Heater Steam

    This practice of considering MDMT as -29 Deg C for CS and -46 Deg C for LTCS is commom. Some time it is due to ignorance and many times as engineering of convenience in order to limit and also standardize piping classes. This does not mean that we can blindly follow this practice, such cases to...
  8. sanshu1111

    PSV SET POINT and ASME standards

    As per the requirement of ASME Sec VIII Div 1, PSV set point (start opening) can not be more than MAWP in case of single relief device. It shall prevent pressure from rising more than 10% or 3 psi (which ever is greater) above the MAWP.
  9. sanshu1111

    Tubesheet/Separator Plate with nozzle

    Bayardwv, Isn't the tube plate design and construction remain the same even with the drain connection on it (except for the drain connection)? This plate will still see only the differential pressure within the filter housing. A sketch will be helpful to understand the construction of drain...
  10. sanshu1111

    MDMT versus Pressure

    UG-20(b) requires that for the marking on the nameplate, MDMT to be established for largest value of MAWP. This clause also allow us to report additional MDMT corresponding to other MAWP's. In case your process ensures that the MDMT of -238 Deg F can not occur at a higher MAWP, you can also...
  11. sanshu1111

    MDMT versus Pressure

    Please refer to UHA 51 (d)(1)(a) which exempt impact test requirements for austenitic steel having carbon content less than 0.1% at MDMT -196 Deg C (-320 Deg F) and warmer.
  12. sanshu1111

    316 SS support ring welded to clad vessel

    Jtseng, If I understand it correctly, your client wants you to weld load bearing support ring directly on the base metal and not on the clad or weld overlaid surface. In such case, you have to strip cladded section, weld the support ring, weld overlay stripped section and them PWHT. As per...
  13. sanshu1111

    Can I weld supports to repad after hydrotest?

    Lets take an example of a small PV where a simple support (a simple plate)is directly welded (without any pad) to the shell (pressure part). This support may be bolted or welded to another structural member for vessel mounting, is this weld or bolted connection within code scope? In my opinion...
  14. sanshu1111

    Can I weld supports to repad after hydrotest?

    U 1 (e)(2) -where non pressure parts are welded directly to either the internal or external pressure retaining surface of a pressure vessel, this scope shall include the design, fabrication, testing, and material requirements established for non pressure part attachments by the applicable...
  15. sanshu1111

    MAWP (LImited By)

    As per ASME Sec VIII (assume that this is the design code), calculation for MAWP is not mandatory and manufacturer can consider MAWP = design pressure unless calculation for MAWP is required as per the user specification/ contract. In case manufacturer has already indicated on GA that MAWP is...

Part and Inventory Search