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  1. rneill

    Nozzle Reinforcement (MAWP or Design Pressure)

    Normally, Client specifications have a conflict resolution process specified and if so, that process would define how to resolve conflicts in their requirements. If the conflict resolution process was not followed then they would be within their rights to require the change. If the process was...
  2. rneill

    900# Weld neck flange design

    I am not an expert but I think the limitation is just for hubbed flanges - my interpretation is the same as your's. Int. 92-37: Question: Is it permissible to fabricate a flange per Appendix 2, Fig. 2-4 sketch (7), by welding a 1" plate conforming to SA-36 to a 3/8" thick nozzle neck...
  3. rneill

    900# Weld neck flange design

    There were not a lot of details around the flange design in your post but I would refer you to ASME Section VIII Appendix 2-2 as there are some specific rules for flanges manufactured from plate. Also applicable is Interpretation VIII-1-92-37.
  4. rneill

    ASME B31.3 piping, hydrostatic pressure test, loose blind flanges

    I agree with the inspector. I do believe it is the intent of code that all components used in a piping system are to be properly tested in accordance with code requirements. I don't really see basis for exempting blind flanges. Note: I routinely apply the same criteria to flanged valves as...
  5. rneill

    Min spacing between 2 welds

    I'd have to go digging but I think there might be something addressing this subject for piping in one of the Pipe Fabrication Institute Standards (ES-7 is minimum spacing between branch connections and it may be mentioned in there else it may be in one of their other standards) and I think it is...
  6. rneill

    Weldolet/Threadolet Trimming

    Quality2479, I'm curious, what is the approximate gap at the skirt of the fitting? Is it within the 1/16" permitted by MSS SP-97?
  7. rneill

    Fullbored or Restricted bored ball vave?

    David, I think you are talking about pipelines predominantly and my experience is predominantly plant piping and it is from that perspective that I responded. I agree that full port may be a more logical choice on pipeline projects. To answer your question about my background, I have worked...
  8. rneill

    Weldolet/Threadolet Trimming

    There are a wide range of manufacturers out there and design / dimensions of weldolets is up to the manufacturer. MSS SP-97 provides design criteria and does not provide dimensions. Consequently, you are trusting that the manufacturer knows what they are doing and that the fitting really is...
  9. rneill

    ISO 15590 Flange Ratings

    I'm pretty sure there is a SNAFU in the standard but the standard has been out for a long time ( 8 or 9 years ) and I can't find any evidense of a correction being published. Regarding ANSI ratings, I'm not sure ... ANSI starts to derate at 38 C whereas pipeline flange ratings in many pipeline...
  10. rneill

    Is stamping heat numbers onto pipe the pipefitters responsibility?

    I would assume that received materials are properly marked (usually stencilled) by the manufacturer and that as bits and pieces are used, these markings are transfered by the workers so that all bits and pieces remain traceable. I would also assume that if full traceability was required, as...
  11. rneill

    Gasket failure in compression

    ASME B16.20 currently requires that spiral wound gaskets (graphite filled) have inner rings unless specified otherwise by the purchaser. In my experience, most purchasers have accepted this change and now purchase with inner rings.
  12. rneill

    Weldolet/Threadolet Trimming

    In Canada, you would invalidate the CRN on the fitting and thus render it unfit for service if you modified it in this way.
  13. rneill

    Fullbored or Restricted bored ball vave?

    there are a number of situations where it would be common to require full bore valves (e.g., relief valve flowpaths - in and out, meter runs, pigging). Many operators have specifications where they list the situations in which they require the use of full port valves. However, if this is not a...
  14. rneill

    ISO 15590 Flange Ratings

    Has anyone looked at the flange rating table in Part 3 of ISO 15590 ... Can anyone explain the high temperature ratings of Class 1500 and 2500 ... Questions: 1. The 250 C rating (225 bar) of Class 1500 is higher than both the 175 and 200 C ratings which are 219 and 225 bar respectively. 2. The...
  15. rneill

    Mating RFWN Flange Joints of Unequal Thickness

    Hmmm, we don't specify the flange bore on the valves we buy and install and we use the same ASME Class 600 flanged valve regardless of whether the attached pipe has a Sch 40 bore or a Sch 160 bore ... we've never worried about it for valves so I'm not sure that this is a real problem ... Of...
  16. rneill

    14" stainless steel pipe thickness

    I think the supplier is basing his sizing on the fact that all the way up to NPS 12, Sch 80S is the same as Sch XS rather than being the same as Sch 80. He is extrapolating this and then assuming that for NPS 14 pipe, Sch 80S would be the same as Sch XS (which is 0.500" thick). Note: Sch 40S...
  17. rneill

    Ring Joint Flange to RF Flange

    You might want to look at the Pikotek VCS gasket. This gasket is designed to be used with either RF or RTJ flanges and can be used to mate RF to RTJ. The sealing element sits on the flange face inside of the ring groove so the groove becomes a redundant feature. The VCS is not fire safe but...
  18. rneill

    Aluminum in CNG Service (NFPA 52)

    Does anyone have any idea why Clause 4.8.4(4) of NFPA 52 specifically prohibits the use of aluminum for pipe, tubing and fittings in CNG service ? I don't have any experience with CNG service but from what research I have conducted, aluminum is a good choice for product compatibility, it has...
  19. rneill

    HIC

    You might want to look at NACE MR0175/ISO 15156 Part 2 Clause 8.5 and NACE Report 8X194. Both documents provide some informal guidance on chemistry criteria that might typically be provided by end users to increase the likelihood of the steel being able to pass the HIC tests. Having said that...
  20. rneill

    visual inspection during hydrotest

    What code are you working to ? Most buried pipelines (pipeline design codes) are tested after they are backfilled. The test is of much longer duration in order for leaks to become noticeable.
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