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Recent content by SPDL310

  1. SPDL310

    Control Valve CFD Analysis

    This is question best posed in the CFD forum. You will be fighting convergence with the pressure inlet/pressure outlet configuration. You will see better convergence with mass flow inlet/pressure outlet.
  2. SPDL310

    Axial Control Valve Sizing

    The 10,000 sm3/h figure seems more reasonable for a low flow scenario, and if that is the case your valve might not be over sized. The point that you seem to be missing is that what people have been trying to tell you is that this inquiry is not how valves are typically supplied. Your customer...
  3. SPDL310

    Axial Control Valve Sizing

    The information you have is not appropriate for sizing a valve as LittleInch has already stated. The customer normally fills out a standard valve spec sheet. It will pair a specific stream condition temp/flow/fluid properties with a given P1/P2 condition or maximum drop. This is determined by...
  4. SPDL310

    Steam Application Valve Stem Material

    At over 1000°F you are probably getting into the creep range of 17-4 and are losing nearly half of your original yield strength. You will also see significant thermal expansion. Keep in mind you will see accelerated pitting and corrosion due to the elevated temperature. At those temperatures I...
  5. SPDL310

    Natural Gas Cavitation

    Please see the following on natural gas behavior. https://petrowiki.spe.org/Natural_gas_properties To fully asses the risks to the valve you should consult with your valve supplier, and process engineer do determine the valve requirements. As others have stated in general you are starting off...
  6. SPDL310

    Natural Gas Cavitation

    If your process modeling shows that your natural gas is 100% gas at the inlet conditions then there can be no cavitation. You are already in the gas region of your bubble-point curve additional pressure drops will not cause cavitation. You are more likely for generate droplets from condensed...
  7. SPDL310

    Closure and Stem Calculation

    There are multiple forces to consider when designing a valve stem, and there are no codified formulations for doing so. To answer your latest question, yes you should consider actuation forces when designing your stem, as well as any intentional or unintentional load that can be applied to the...
  8. SPDL310

    Stellite 6 over Alloy 625 weld overlay

    To answer your questions: 1.) This is typically what is called a butter pass. The alloy 625 is used as a buffer between two incompatible materials. Welding the Stellite directly to the F44 may cause cracking and non-boded material. 2.) for the correct procedure you would need to check with a...
  9. SPDL310

    Traditional FEM Method(ANSYS- ABAQUS) or New Approach (Boundary value Method) in ASME SEC VIII Div2

    If you are already using other FEM methods with regularity and success what is driving your desire to use different approach? Have you validated the accuracy of the method/software by reproducing the results of past analyses or example problems from the ASME PTB example problems manual? Can you...
  10. SPDL310

    API Q1 and R&D department (?)

    Q1 does not mandate any defined organizational structure. Where R&D is placed in the org would depend on the duties it performs, but in most cases I would assume it falls underneath the umbrella of the engineering department. If R&D is tasked with the development of of new products and...
  11. SPDL310

    How to change element type in ANSYS Workbench 2023 R1

    While using WB the element selection is somewhat limited. In order to use a shell element you would need to be meshing a surface geometry and not a volume. If you have defined a given thickness ie. defined the in and outer boundaries of your surface WB will mesh it with solid elements which is...
  12. SPDL310

    Fluorescent dye and Wetting agent for Hydro test medium (water)

    The acceptability of the proposed alternative procedure is at your client's discretion. I doubt the use of digital pressure transducers will be considered an acceptable alternative to the dye. I believe that the purpose of the dye test is to drive the dye into any surface cracks that may open...
  13. SPDL310

    PR(Performance Requirement) Requirement in API 6A Product

    For valves 1 test cycle is considered from full open to fully closed or fully closed to fully open under differential pressure for shut off valves. For static equipment it is generally considered from no pressure to full rated pressure for a designated hold period, and back to atmospheric...
  14. SPDL310

    Minimum Thickness with changing radius

    There are too many API standards to know which one you are talking about, but most of the valve codes do not prescribe a required wall calculation method. A corrosion allowance is normally applied to the calculations that I perform. For standards where a wall thickness calculation is given...
  15. SPDL310

    PR(Performance Requirement) Requirement in API 6A Product

    You may want to refer to API 6A Annex B for which PR and PSL levels are recommended for certain applications. As a rule of thumb a majority API valve products are sold as PR2. On to your questions. 1.) The manufacturer will label which of their products are PR1, PR2 or PR2F. 2.) My...

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