Side outlets on Drilling spools are to be checked for stress in accordance with API 16A 4e, Refer Section 5.4 Design Methods, The Spec provides two methods ASME Method (ASME Sect VIII Div2, Appendix4) OR Distortion energy Method, The ASME method yields more conservative results and is a generally accepted method.
In case the loads are known you may want refer to API 6AF, this document provides good guidance on API flanges under combined loads.
The reference (ASME Sect VIII Div2, Appendix4) only appears in 2004 and earlier editions of ASME Sect VIII Div2.
In 2007, VIII-2 was re-written and the above mentioned reference you cannot find in 2007 and later editions.
Javed Nasir
Inspection Engineer
Technip-France Abu Dhabi
You are correct in that the post 2004 ASME Code lacks the reference mentioned in my email above. I apologize for the lack of detail in my earlier response and hope to clarify further.
I Refer API 16A 4e Section 4.4 Design Methods -> 4.4.2.2 Design Methodology, makes reference to API6X 1e (Design Calculations for Pressure Containing Equipment) released March 2014. Within API 6X I make reference to to Section 2 Normative References this states " No other document is identified as indispensable or required for the application of this standard " this means that no other specification/ Standard or document is absolutely necessary or required in applying this standard i.e it is a stand alone document.
Further More, API6X Sect.1 states the following: This standard is based on ASME Boiler and Pressure Vessel Code, Section VIII, Division 2, Appendix 4
(2004 edition with 2005 and 2006 addenda) but includes further limits established for oil and gas products as
determined by API standardization committees. It includes closed-form solutions and methods for elastic
analysis, elastic-plastic analysis, and guidance on finite element analysis methods. The methodology
assumes ductile metallic material behavior and has no provision for material defects.
Sect.4 of the standard provides further information on Elastic Analysis, application of the same should be performed by a qualified engineer, resulting stress check may be further verified using FEA.
