Mr. Richard Ay,

Please confirm which option is correct to override the SIF,

We calculated the SIF for 45 deg lateral tee through FEM and compared with french code and found to be same (approx.).

Case-1: I defined the SIF in the following way,

Node: 100
Type - Blank
SIF(i) - 5
SIF (o) - 6

Case-2:

Node: 100
Type - Reinforced
SIF(i) - 5
SIF (o) - 6
Pad Thk. - 10

The stress values in both case-1 and case-2 are different. Please clarify which method is applicable.

Sillyman,

I guess you'd like to look into this too!!!It describes both the simple as well as complex methods for incoroporating user defined SIFs.

By the way, you've not mentioned the type of branch connection for which you've calculated SIF.

Mr. SJ,

Thankyou very much for your valuable reply. So from your information, it is seen that Case-2 as i mentioned earlier is the valid process to define the override SIF value.

I calculated the SIF for 45 deg lateral tee with RF pad of 10mm thick.

Please correct me, if am wrong.

Mate,

You're right now because if you don't specify the type of branch connection,CII can't calculate the SIFs for neither the header nor the branch (in case,if a code defined connection).By omitting the type of connection, you'll omit Header SIF which can be calculated in your case (since its code recognised one).Your case two is valid.

Hope this helps!!!

And I like your tag line "Knowledge is nothing unless shared"!!!

My final query is,

In the finite element analysis, as i provide the RF pad with 10mm thick, the SIF value is reduced compared to connection without RF pad. Again when i increase the thickness of RF pad to 15mm, the SIF value is reduced. So in calculating the SIF through FEA software, it considers the RF pad thickness in calculating the SIF.

The SIF from FEA is then input in the Caesar-II spreadsheet. Where am i have to put only the SIF values calculated from the FEA by leaving the "Type" as blank or i have to mention the "Type" of intersection.

Why because, when i leave "Type" as blank, the stresses are more than the allowable and when i fill the "type" the stresses are reduced. if i use the later option, it seems to me that apart from the FEA SIF value calculation (which consider the RF pad thickness), we are again making the advantage of RF pad in Caesar-II by inputing it in the "Type".

Please clarify....

Mr. SJ,

Thanks for your reply and comment on my tag....

Sorry..I just mixed it up!!!My mistake!!!

Well, since you're defining a connection which is not defined in Code (App D).The method I quoted above applies for the one which are defined by code (like if you want to use more accurate SIF values).

Just check your SIF reports in output? It will read different values than what you've entered!!

I initially thought that you're using a welding tee with RF pad!!(Sorry..was busy with work ...so couldn't go thru your entire post).

Mr. Richard Ay, Mr. Dave and forum members,

I am waiting for the reply !!!!

You should specify the proper Tee Type, so CAESAR II can properly determine "in-plane" versus "out-of-plane" directions. If you leave the type blank, you're counting on CAESAR II guessing which is which. Sometimes that won't be right.

Mr. Richard Ay,

I think i did not explain my query in an understandable way.

Let me try to explain with reference to Caesar-II version 5.1, Technical reference manual, stress intensification factor details, in example it is shown that the SIF for header (ii = 4.5, io = 3.75) and branch (ii = 6.7, io = 5.58) connection are different.

Firstly, the query is, How the SIF values for header and branch are different (in which code or which case)!!!

Secondly, In overriding the code-calculated SIF, it is shown that the header SIF have to modified as:

35 to 40 Node 40
Type:
SIF(i): 2.3
SIF(o):1.87

40 to 45 Node 40
Type:
SIF(i): 2.3
SIF(o):1.87

Query is what will happen if I mention the type of branch in the "Type" field above (in the technical reference manual the type of branch is unreinforced branch connection, in my case, say for ex. 45 deg lateral tee). Also it is shown that for overriding we need to enter the SIF in all three node common junction (Node 40, to reflect in the stress calculation). Is it so!!!!

If there are some SIF due to torsion where i can input in caesar-II spreadsheet?


Kindly reply and clarify...

Yes you have to specify the over-riding SIF values on all three pipes framing into the tee. You should specify a tee type, so that CAESAR II knows it is a tee (as opposed to some point you're applying an SIF to), which enables the software to determine the "in-plane" versus "out-of-plane" directions.

At this time, CAESAR II does not apply SIFs to torsional moments (unless you're implementing a Code like B31.1 which performs an SRSS on all 3 moments before applying the SIF).

As to your question on the Technical Reference Manual, what page are you talking about?

Mr. Richard Ay,

Thanks for your reply and please find attached file in which i shown as much detail as i can and please confirm the requirement.

The attachment contains the following,

Caesar SIF input and Stress report is provided
Three cases are shown
1st case - Type is left blank - Stress value "PASS"
2nd case - Type is indicated (Un-reinforced) - Stress value "FAIL"
3rd case - Type is indicated (Reinforced 14mm thk RF pad) - Stress value "FAIL"
Summary of each case provided
Queries are listed in the 3rd case

As to your question on the Technical Reference Manual, the page # is 3-28 & 3-29.

Please correct me, if i am wrong.

I don't have the 5.1 mannual with me. However the 5.30 manual states:

If the node is not at an intersection or a joint then the
Type field should be left BLANK and the "USER DEFINED" SIFs entered in the SIF(i) and SIF(o) fields. User entries in the SIF(i) and SIF(o) fields only apply to the element on which they are defined.

The key here for you is the phrase "not at an intersection". You do have an intersection so you should enter the tee type. Because you're entering both SIFs, and since the Code defines tee flexibilities as 1.0, it doesn't matter what tee type you select - you'll get the same result.

Mr. Richard Ay,

Thanks for your reply. Again my requirement is not reached you clearly. Small mismatch happened, the pages i mentioned in Technical Reference Manual of 5.1 are the page # is 3-28 & 3-29 and it is not same in the 5.3 manual. In 5.3, the equivalent page # are 3-32 & 3-33. Please find attached Technical Reference Manual of 5.3 of the SIF/tee topic in which i marked the requirements.

Please clarify it...

Referencing your PDF:

1) The SIFs for header and branch can be different if: (a) the applicable code employs a "branch equation" and your geometry meets the criteria, or (b) the Schneider option is turned on in the Configuration, or (c) you've performed an FEA analysis.

As to what was used in this particular example in the manual, I don't know. The intent here was to show how to manually over-ride the Code SIFs.

2) The clouded sentence never said to leave the "type" field blank - all though the example does leave this field empty. As I've stated above - DON'T DO THIS! You need to specify the type, otherwise CAESAR II can't tell in-plane from out-of-plane.

3) How can you define your lateral? This is not a Code fitting, which is why "lateral" isn't one of the typs you can select. Just select "unreinforced" and define the SIF values. As I said above, "because you're entering both SIFs, and since the Code defines tee flexibilities as 1.0, it doesn't matter what tee type you select - you'll get the same result."

4) You last clouded sentence is saying that if you over-ride the SIFs for one element framing into an intersection your really need to over-ride the values for the other two elements also. If you don't do this, then the standard Code computed SIFs will be applied to those elements you didn't over-ride.

Mr. Richard Ay,

Thanks for your reply.

Reference to your points,

1. Agreed.

2. Is the same shall be updated in the Technical reference manual of next revision.

3. Agreed.

4. Agreed.