Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations cowski 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: *

  • Users: trottiey
  • Content: Threads
  • Order by date
  1. trottiey

    Aid organizations working in radiological zones

    Some aid organizations are pulling out of Japan, citing a lack of training and equipment to work in a radiological zone. But Doctors without Borders has equipped their personnel with radiometers and expressed a willingness to rise to the challenge of the Fukushima incident, within limits...
  2. trottiey

    Radiation protection 101 for Fukushima

    There are two types of exposure to radiation: internal and external. External exposure refers to direct irradiation, like exposure to the sun. If you can shield it or walk away, the external exposure stops. Internal exposure refers to inhaling or ingesting radioactive contaminants, or otherwise...
  3. trottiey

    Japanese nuclear accident FAQ

    Since my other thread is getting a little unwieldy, I thought I would start this one to summarize frequently asked questions: 1) What type of reactors are these? Fukushima Dai-ichi Unit 1: BWR-3, 460 MW, activated 1970 Unit 2: BWR-4, 784 MW, activated 1974 Unit 3: BWR-4, 784 MW, activated 1976...
  4. trottiey

    Fukushima No. 1 loss of coolant due to earthquake

    I'm sure we're all anxiously waiting for some technically accurate news, so if you hear anything credible, please post it here. Latest report that I have says that the reactor is shutdown, but coolant pumps are not running because of the power outage and failure of their auxillary generator...
  5. trottiey

    Does B31.3 permit tube socket welds?

    Does B31.3 permit socket welds on thin-walled tube? Paragraph 311.2.5 says socket dimensions shall conform to B16.11 or SP-119, which only include pipe dimensions. So does that exclude any socket welds on 3/8" OD X .065" wall tubes? Does it exclude Swagelok TSW fittings, or is that fair use of...
  6. trottiey

    Section III Jacket penetration weld details

    I posted thread794-291562 on the Boiler and Pressure Vessel forum a couple of days ago. It hasn't received any reply on that forum, so I thought I would check here to see if I could raise any interest. Please post any replies over on that forum. Thanks.
  7. trottiey

    Section III, Jacket penetration weld details

    I'm a bit stumped as to how to design the weld joint for a nozzle penetration through a jacket wall under Section III Part ND. Under Section VIII, this would be straightforward: Appendix 9, preamble to 9-4 gives you exemptions from the basic code, and Figure 9-6(a) is pretty close to what I...
  8. trottiey

    Translation modifier versus MMB modifier

    I've been reading up on the new translation modifier in the 2009 version of ASME Y14.5. I'm trying to get a feel for when it should be used. At first reading, it sounded like it should be applied to any datum used for clocking. (i.e., on any tertiary or secondary datum used to constrain rotation...
  9. trottiey

    Voids in SB-550 zirc bar

    Machining uncovered some large internal flaws in SB-550 zirc bar, 4.5" diameter round. These flaws are several inches long and almost one-eighth inch in width. Is this normal? To my mind, "bar" implies hot-rolling which would squeeze out voids this size. The scary part is that I had planned on...
  10. trottiey

    Purpose of nonessential variables?

    Why does Section IX require nonessential variables to be recorded on the WPS, if they can be revised arbitrarily without requalification? I'm looking at WPS's where the nonessential variable ranges have been extended beyond what can realistically allow a good weld. That would seem to reduce the...
  11. trottiey

    Weld contour within tolerances

    Do welds have to meet the bulk dimensions and tolerances of the part? Intuitively, I thought that weld beads would only have to meet if the weld symbol indicates a flat or concave contour. If the weld symbol indicates a convex contour, which is the default, I'm used to seeing big rugged weld...
  12. trottiey

    Wire rope length change as it twists

    I'm looking for an equation or chart that could tell me how much a wire rope shortens if you twist it. I'm not talking about the length change of the strands during manufacture of the rope. If you take a finished rope and twist it further, how much will it shorten per turn? I've looked through...

Part and Inventory Search