Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

Search results for query: *

  1. valleytank

    Double bevel on vertical seam

    It isn't really thick enough to warrant a double-v prep from the start. In my opinion keep the single-v, deposit your root and hot pass, go back inside and backgouge the square edge back to your original root and dress it up to the same V prep angle. VT/MT back gouged/ground surface. Deposit...
  2. valleytank

    Roundness and plumbness

    At that point 'not good enough' would result in the TPI getting a beat down. Ask him to provide you WHAT information would satisfy him THEN ask him to reference some or any tolerances for a tank built via this method. It's not black and white. At the end like previously stated the final result...
  3. valleytank

    banding measurement

    Its utilized in the fabrication to control out of line plates via periodic sweep / band checks. If you're doing this in service you're better off contacting a survey crew to give you a shell readout where you can see the out of round. At the end of the day even if it is out by certain...
  4. valleytank

    Replacing Floor Plate - Remove Rust Scale?

    You're replacing an entire floor and didn't anticipate having foundation rework in the process? Possibly some added drainage? If not, then it's obvious that the remnants of rust scale and possibly contaminated ones aren't a major concern. But.. id take it out. It's a shame to go through that...
  5. valleytank

    Telltale Hole Location API 650 Tank

    Never put them too close to the edge. You will get some deformed whatever-NPT hole after the welding is complete and the repad sucks back to the curvature of the tank. Do what IFRs suggested. If the repad is split along the centerline offset your weepholes down/up 2"/6t off that weld centerline.
  6. valleytank

    NDT for Annular plates for API 650 storage tanks

    1. It is acceptable to perform shearwave UT on annular ring radial joints. Very common on existing annular ring repairs. Remember this is very operator dependent so get someone who knows what they are seeing or you'll be hurting. 2. In regards to the RT requirements as Samm17 mentioned it...
  7. valleytank

    Repair of corrosion hole on nozzle

    How thick is the manway neck? Is it one continuous rolled plate with a butt-welded long seam? Or is it an older 12c style with the two press-formed halves with one big circ-seam joining them?
  8. valleytank

    Water Tank Strengthening

    Bimr hit the nail on the head with the first post. I actually started to reply about rolled plate, one long seam with two formed heads, combine nozzles into single repad, yada yada. Obviously this is for a hobby and doesn't follow code.
  9. valleytank

    API 650, Bottom Plate & Annular plate

    Not Required but I am assuming low stresses for that size of tank. See section 5.5 of 650 for more info.
  10. valleytank

    API 650, Bottom Plate & Annular plate

    What are your shell stresses and bottom course material?
  11. valleytank

    NOZZLE NECK MADE FROM PLATE

    I've done it on built-up manways but I'm just curious why in this situation you are requested to fabricate a nozzle neck out of rolled plate. Its perfectly fine but in most cases some seamless A106B will suffice.
  12. valleytank

    Qualified thickness of nozzle to shell with pad (ASME Sec IX)

    It's a corner weld, meaning its a single process from one side and you need to qualify your guy for that shell thickness which is easy to do at a 1/2" test. Should be good to backgouge and fill the remainder up with a heavy wall ticket.
  13. valleytank

    Vent-hole on the reinfrocement pad, wedding band (discussion)

    There is already a much better way to achieve this connection of yours that was already hinted at with the appropriate internal bevel that is easy to achieve and butt weld-out/xray/mag do what you need to do. Ditch the threaded plugs altogether like 11echo mentioned. They are always weak points...
  14. valleytank

    What level of material traceability ids required for API 650 tanks?

    Requirements for material traceability are not specified in the code other than every material must be identified and if it cannot be... to follow Appendix N and Purchaser specifications/requirements. Due to this plate being for cold service hence the impact requirements (350WT) this makes...
  15. valleytank

    Flush Type Clean out Door NDT Reqd.

    Duwe6, With your UT experience if you had a similar corner joint as seen in the above 'Detail 4'.. but with a full-penetration weld throughout the insert and repad thickness; Is this something a competent level II UT could handle in a shop environment or would you be leaning more towards PAUT...
  16. valleytank

    Actual thickness and stress relief

    You are permitted an under-run of not more than 0.3 mm (0.01 in.) from the computed design thickness or the minimum permitted thickness of plates ordered. Now this does not say anything about being over... Personally I would agree that Stress-Relieving is not required for this thickness. Both 11...
  17. valleytank

    API 650 -SECTION 5—DESIGN

    Even though 5t spacing is the bare minimum I suggest you increase this distance to space out your areas of residual stress in closely concentrated seam intersections.
  18. valleytank

    UT of in service tanks

    mmchugh2, These are very common inspections that should be no problem for the avarage NDE outfit...if they can deal with a rental but the bigger ones like Team Industrial or Acuren would provide you with a tank crawler Link with a probe on it that feeds back readings to the UT set below...
  19. valleytank

    Shell and roof manhole

    What Duwe6 said. Why in the world would you even consider the alternative originally posted? Anyone else getting tired of people doing everything and anything possible to cover their butts no matter what the cost and effort vs doing a little research, crunching some numbers if needed, and...
  20. valleytank

    Anchor bolts and grounding lugs

    You will find ground lugs much more effective as well as they are typically connected via heavy gauge wire to grounding rods which are driven a fair length into the ground while your anchors are only embedded into your concrete.
Back
Top