Can someone give me reference of any document( or paragraph of code etc.)which says what should be the intent of the applied loading( ie remain operational without repairing or remain operational with repairing or may not remain operational but there should not be any pressure boundary violation etc.)for pumps ( centrifugal , API 610 and Reciprocating, API674) in OBE and SSE level earthquakes.The project is a pipeline project and code of practice for piping is B31.3/B31.4.

I did not find anything specific in SEC III on this.

Thanks in advance

Regards

This information is available in your seismic design code. Generally, this is a Building Code like the IBC, but you need to know what your contractual obligations are, and also what the regulatory requirements are. This information may be difficult for you to obtain, but since it's required you'd better get busy on it.

Craig,

The seismic design code ( by this I understand you mean the project specific seismic design code)does not say anything specific on this.The seismic design for the piping system is as per ASCE-7.We have to specify this in our Piping dedesign code( Project specific).

One of the way is to go to the client on this question, which definitely I will do, but otherwise, is there anything in SEC III which says what should be the intent of the OBE/SSE level loading on Pumps ie should they remain operational w/o any repair in case of OBE and in case of SSE the pump need not remain operational but there should not be any pressure boundary violation? I understand this should be the philosophy based on what I understood from subsection NF for supports. I however did not find anything similar in case of pumps.

I am searching for this answer which will be the basis for my argument which I want to base on the code intent( although this is not a nuclear project, but a project with piping code B31.3/31.4)for the loading level in OBE and SSE.

I understand that OBE level is Service Level B ie upset and SSE level is Service level D ie Faulted.

Regards

DEAR ANINDYA,
I HAVE WORK WITH B31.1 AND B31.3 CODES AND ALSO HAVE AN EXPERIENCE OF WORKING ON SECTION III ALSO. ACTUALLY ON SECTION III THE PHILOSPHY OF STRESS ANALYSIS IS DIFFERENT. BUT PUPOSE IS SAME. U CAN CHECK FOR OBE AND SSE DIRECTLY FROM EQUATION 8,9,10 AND 11 OF SECTION III. BUT FOR ANYOTHER CODE U HAVE TO PERFORM DETAIL STRESS ANALYSIS WHICH ALSO INCORPORATE OBE AND SSE DEPENDING UPON UR LOADING AND LOAD COMBINATIONS. MOSTLY THE WORK IS DONE ON CEASAR AND DONT GO FOR EQUATIONS 8,9,10,11 MANULAY. SSE IS FAULTED CONDITION INWHCIH PLANT WILL SHUT AND CANNOT START WITHOUT REPAIR AND OBE OPERTIONAL REPAIR OF OPERTAIONAL NOT REPAIR CONDITIONS OF PLANT. THIS DEFINITION OF OBE AND SSE IS UNIVERSAL AND CAN APPLY TO ANY CODE U R WORKING ONLY STRESS LIMIT MAY VARY FROM CODE TO CODE U HAVE TO CONCENTRATE ON THESE STERSS LIMITS ONLY.
REGARDS

Dear Sameer,

Thanks for the input.

The problem is not with the pipe stress. The problem is with the definition of OBE and SSE Level on equipment loadings. Till now I could not find any specific paragraph in ASME SEC III saying what should be the criteria of equipment loading ( say on pumps) in OBE level.OBE level as I understand is service level B ( upset) and SSE service level D( faulted) and in faulted condition, ( this is what I understand from APPENDIX F and Appendix N and companion guide to ASME B&PV code vil 1 and 2)only the equipments pertaining to safety need be operational and there should not be any pressure boundary violation but other equipments may not remain operational. However when it is OBE should the loading on pump be such that there may be requirement for repair but the pump will stay operational( after repair)?

I could not find anything in SEC III ( or NFPA 59,although my project is neither nuclear nor LNG) which specifically says what should be the intent of OBE and SSE level loading on pumps.Can you or anybody throw some light on it?