Thursday, June 7, 2007

Email notification

How would you like to get an email notifying you when I have posted another blog? You can! Just look for the subscription sign up on my blog page. When you subscribe, you will receive an email the morning after I make a post. It will give you a brief idea on the topic posted. This way you will know when a post has been made without having to constantly check to determine if there is one.

Tuesday, June 5, 2007

API-650 meeting

It has been too long since I did the first post. I need to catch you up on what is coming with regards to API-650.

An errata was issued in April following the committee meetings in Seattle. Most of the changes did not have an affect on our ITSdesign program as they were more notation in nature.
1) The changes to Equations E-18 and E-21 did affect the program and have been changed. They actually reduce the seismic load.
2) We had changed Equation E-20 and E. (second equation and fourth equation) quite a while ago.
3) There still seems to be a problem with what they have shown for Equation E-23a and E-23b. It would seem that E-23a should have a factor of 196 not 1.96 and that E-23b should either be 1.28 or 1.25 but not 1.96.
4) Equation E. (third equation) should still have a factor of 83 not 8 as shown.
5) Equation E.7.2 (second and fourth equations) where corrected to remove the I and replace it with 1.
6) There seems to be a problem with the equation changes in V.7.3.3, V.7.3.4, V. and V. For the first two equations, if the factor for the US units is correct then the factor for the SI units should be 19.0 and 13.4 respectively. The 13.4 factor corresponds to what is used elsewhere in the save appendix and elsewhere in the code. The latter two equations do not make any sense as they did not even show the original equation correctly to begin with. As such we have currently left all of these equations as in the orginal Addendum 4.
7) The change in V.8.2.3 from 32tb to 16tb was in our original program change as we did not feel this was correct to begin with.
8) The change in the example equation of V.10.2 corresponds to what we have built into our program except that according to the definition of fc, it does not have to be less than 15000 psi.

The 11th Edition of API-650 is about to be released. I just received an email stating that the final review was completed today and it will be released (I assume to the printers). I would expect to see something in the next few weeks. At the meeting they indicated it would be released sometime in June and it appears that is going to happen. Once that is released we will see what changes they have made. Along with that I would expect an addendum to the 11th Edition to be coming out by the end of the year.

There were many interesting things discussed at the meeting in Seattle. Some where just for discussion and some are going to be coming sometime in the near (??) future. A few of the items being discussed are:
1) They are looking at adding 201 and 201LN material to Appendix S.
2) They are working on an appendix that would add duplex stainless to the code.
3) They are workng on an appendix that would add mixed materials (carbon steel, duplex stainless, and austenitic stainless). You would then be able to use these materials in various combinations in one tank. You could then have a duplex stainless bottom and first ring and the rest carbon steel or other combinations.
4) There are modifications to the safety factors for Appendix V being worked on.
5) The problem of using narrow plates shop welded to make shell plates is being addressed along with the extent and location of x-rays required.
6) Shell nozzles larger than 48" are being worked on.

It will be interesting to see how much of this is included in the 11th Edition or the first addendum when it comes out. I will keep you posted.