Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

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

Search results for query: *

  1. narenr

    Overage length laydown and expansion loops

    Zoomi, the overlength required is the the pull in though the J-tube, you could get the actual lenght from the J-tube lenght + the lenght required for tie-in + the slack required for laydown. Your pipeline engineering performing the J-tube pull-in analysis could provide this. Narendranath R...
  2. narenr

    Intelligent pigging - minimum velocity?

    The minimum velocity required for pigging is 0.5m/s, the optimal for MFL tools is 0.5~1m/s for liquid pipelines and 3~8m/s for gas pipeline. For liquid line, to achieve high pressure/velocity you could use water [off course treated and inhibited] with additional pump. The IP vendors data...
  3. narenr

    Bracelet Anode Length

    Contact the manufacturer for his tolerances, CP Tech & Alico will produce with a minimum of 300mm for bracelet anodes. The insert dimension and the anode thickness will govern the minimum length of anode with due consideration for shrinkage and cracking. If you are using DnV RP F103, you can...
  4. narenr

    Pipeline welding

    Specification normally ask for about 150mm of the weld bead will be ground with not more than 0.5mm projection. Narendranath R Pipeline engineering is made easy with state of the art computer software, visit www.narendranath.itgo.com.
  5. narenr

    Offshore pipeline installation start-up

    ekaputra, The installation analysis will take care of the stresses. Narendranath R Pipeline engineering is made easy with state of the art computer software, visit www.narendranath.itgo.com.
  6. narenr

    Offshore pipeline installation start-up

    Pros: 1] Easy to install 2] Flexible to manoveure the barge 3] Easy to connect the fuse soft rope Cons: 1] Too much load at one point on the jacket leg 2] Larger tolerance on the target point 3] Target point would much away from the jacket base requiring longer riser tie-in spool 4] Most...
  7. narenr

    subsea pipe in pipe insulation

    Just run a pipesim simulation with various insulation thickness till you arrive at your desired outlet temperature. Narendranath R Pipeline engineering is made easy with state of the art computer software, visit www.narendranath.itgo.com.
  8. narenr

    Intelligent Pigging

    IP tools will be configured to suit change in wall thickness along the pipeline, what you need to consider is the tapering of the wall thickness change (1:4 normally. IP tools [both MFL and UT] have a maximum wall thickness limitation for a particular diameter. I would suggest you consult IP...
  9. narenr

    Reinforced Wye

    I would presume the Wye is in the midline then B31.3 is not applicable at all. Use BPV for preliminary sizing and validate it with FEA. The key aspect is to fix the geometry for safe passage of the pig without being stalled or stuck. Rgds Naren Narendranath R Pipeline engineering is made...
  10. narenr

    Procedure for digging buried offshore pipeline

    Excavation for pipeline depends on the water depth, soil type and extent of excavation required. For excavation around an existing pipeline for tie-in of a new pipelinie, you could mostly likely adopt jetting if the soil is loose. Your procedure needs to take care not to damage or loose...
  11. narenr

    Trench and Natural Backfill

    This is partially addressed in DnVRPF109, the code for pipeline stability. Refer para 4.4 for seabed movement. You could also refer Shore protection manual for sheild's criteria. Rgds Naren Narendranath R Pipeline engineering is made easy with state of the art computer software, visit...
  12. narenr

    Handbook on Design and Operation of Flexible Pipes

    This is a JIP report, contact info@sintef.no for info Rgds Naren Narendranath R Pipeline engineering is made easy with state of the art computer software, visit www.narendranath.itgo.com.
  13. narenr

    Threaded hardware used at diver depths

    All coatings are prone for damage during torquing. For subsea applications, bolts are either PTFE or Teflon coated. The concern is not more on coating damage but more on slipping. Rgds Naren Narendranath R Pipeline engineering is made easy with state of the art computer software, visit...
  14. narenr

    Calculating weight of items in seawater

    You question is tricky, you have not indicated where all the component will be?? is it all exposed to water or inside a capsule?? If the components are all enclosed in a capsule [like in most ROVs], your total machine weight in water would be the total weight of all the components in air minus...
  15. narenr

    Offshore Pipeline Leak : Preservation Method

    Brinker platelets works only if there is a small leak not on parted pipes. Assuming there is diver access, the diver can insert an inflatable plug [http://www.inpipeproducts.com/products/testing_isolation/], but before that corrosion inhibitor has be be injected from the other end of the...
  16. narenr

    Offshore Riser Design

    Pigging loads are considered for large diameter risers bends. Particularly if the pig launcher is vertical, the pig will drop on to the bend [force = pig weight x velocity]. The riser bottom bend is also analysed for pig and slug loads. Narendranath R Pipeline engineering is made easy with...
  17. narenr

    Seismic design guideline

    Refer Guideline for design of buried pipelines issued by American Lifelines Alliance, you can download the document at www.americanlifelinesalliance.org. This documents explains the design principles for earthquake design of pipelines with an example. Rgds Naren Narendranath R Pipeline...
  18. narenr

    Vessel motions during pipelaying

    Yes Robert Mahalay is the developer of OFFPIPE software. It was the first commercial offshore pipelay and the most popular one. He had done a lot of work on pipelay analysis. His OTC papers are avialable. Narendranath R Pipeline engineering is made easy with state of the art computer software...
  19. narenr

    Does a stone sinking in ocean get crushed?!

    Yes, the external pressure crushes the stone (or any other material) as it sinks to a depth when the hydrostatic pressure is equal to the crushing strength. The crushing strength again depends on several factors such as porosity (water fill) and shape. The best examples are the lava and fine...
  20. narenr

    pipeline anode temp

    If you have made teh OHTC calculation, then just calculate the heat transfer across each layer till you get the anode surface temperature. See attached spreadsheet typically used for calculating the anode temperature. This process actually helps in reducing the anode quantity for long...

Part and Inventory Search