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Recent content by mechengr12

  1. mechengr12

    Code Requirements for section of shell replacement of A-286C to A516-70

    I have a 50% caustic storage tank designed per API650 that has a Ni repad on ID for a steam tube. The weld of theB162 Nickel plate to the A283C plate failed and the shell has buckled and there is some signs of Caustic SCC. I would like to have a tombstone shape cutout and replace the CS shell...
  2. mechengr12

    Pump shaft key measurements - typically measured from edge or center?

    On pump shaft drawings that list the depth of the key way is the depth measured on the sides or in the center. If measured in the center then the downward curvature would mean the edges would not be as deep. The drawing does not specify where the measurement is taken from. Is there a standard...
  3. mechengr12

    Detroit Diesel 92 Series Fire Water Pump Reliability Issues

    I have two Detroit Diesels Model #8064-7612 92 Series DDC Engine which are our emergency backup Fire Water Pump engines. They are run weekly per NFPA 25 standards and have exhibited poor reliability over the years. Part of the reliability issues have been turbos which develop leaks and catch...
  4. mechengr12

    Material Options for Cryogenic Nitrogen Seal Faces

    flexibox, Thanks for the response. I have ordered a John Crane seal, but was wondering if you had any recommendations on the rotating and non-rotating faces. Are there any good combinations for Tungsten Carbide paired with a harder material? Something like carbon or TC against TC?
  5. mechengr12

    Material Options for Cryogenic Nitrogen Seal Faces

    I am looking for some help and recommendations on cryogenic nitrogen service seal faces. I currently use a Tungsten Carbide to PPCF polymer faces as in the link below. http://www.ppcmechanicalseals.com/PDFs/Cryogenic-Brochure.pdf We have significant seal issues and typically get a few days to...
  6. mechengr12

    Pump Shaft Diameter dimensional tolerances

    I am having new pump shafts manufactured and was wondering where I would go for detailed information on the dimensional tolerances for the manufacturing of the shaft. What API standard list the requirements for the diameter tolerances?
  7. mechengr12

    Cutting permanent door sheet in API 650 Tank that is no longer in service

    I guess my concern is that if the tank was to remain outside in an area that can be prone to high wind speeds from hurricanes and the diameter of the tank is only 12' ID, 24' Tall, and 3/8" SA-283-C Plate would there be any long term concerns if a 6' tall by 3.5' wide "door sheet" was cut out.
  8. mechengr12

    Cutting permanent door sheet in API 650 Tank that is no longer in service

    My site has an existing tank that is no longer used and the HAZMAT team would like a small door sheet like cut out for training purposes. This would allow the HAZMAT responders to perform rescue attempts in confined spaces with supplied air. The question I have is how do I determine the...
  9. mechengr12

    Underground CS piping flange and bolt corrosion rates

    Long story short currently have a carbon steel pipe buried underground with two exposed flanges and flanged valve all underground. Carbon steel nuts and bolts were used. Plan was to leave the hole open until the next outage in 2-3 years and then redo the piping to remove the valve and add a...
  10. mechengr12

    Averaging thickness readings in a pitted exchanger shell

    I have a coded hair pin exchanger with general pitting. If certain pits are below tmin, what guidance should I follow for taking an average of the area? API 510 7.4.3? Can someone give me a quick understanding of general corrosion and pitting guidance that is a good practice to follow for...
  11. mechengr12

    Requirements for manufacturing flanges in shop for exchangers

    Thanks in advance for any answers to my questions. I have an exchanger with a machined flange that is used as a slip on with a groove for a split ring to connect the barrel of a hairpin exchanger. What requirements are there for a shop making this flange? Does it require a coded shop to make the...
  12. mechengr12

    Isolation blind thickness for hydro test

    During the shutdown I am planning on performing a hydro test on an exchanger and must install two blinds. These will be temporary and will not hold pressure for long. History reports noted that the spacing between flanges was to thin to meet ASME B31.3 blank calculations for thickness. The pipe...
  13. mechengr12

    Piping with possible thermal expansion loop needed to pump suctions

    This attachment is the run of pipe from the previous ISO to the pump suctions.http://files.engineering.com/getfile.aspx?folder=5d6a577c-4df6-4f9b-b9de-3135ef0ed58a&file=FMP_3.PNG
  14. mechengr12

    Piping with possible thermal expansion loop needed to pump suctions

    3D model of pipe.http://files.engineering.com/getfile.aspx?folder=b8fb9c1d-b793-4588-aa7f-ba298d20e907&file=FMP_1.PNG
  15. mechengr12

    Piping with possible thermal expansion loop needed to pump suctions

    Looking from a little advice from some piping engineers regarding a modification I would like to make to save labor and materials. During construction a feed line operating at 235degF and 30psig was designed with what appears to be a small expansion loop. I would like to remove the extra run and...

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