Proper documentation of the stress calculation performed using Caesar II or any other stress analysis software is very important as the report or documents are the final deliverables to the client. So one should incorporate each and every detail of the analysis, assumptions if any, the basis of design, etc. in the final report. Every organization must have its standard format of reporting but the same changes slightly from project to project depending on client requirements. In this article, I will try to highlight major points which must be included in the final report before sending it to the client for approval.
Pipe Stress Analysis Report Front Page
Each final report starts with a very nice front page. The front page normally includes the project name; project no, client name with logo, PMC name with logo, and the performing organization or EPC consultant name with logo. It should also include the name of the stress system and the system number for which the report is prepared.
Contents of Pipe Stress Analysis Report
On the 2nd page normally it is better to include a table with revision details, name of performer, checker, and approver along with signature and report issue date. It informs the client about the responsible persons who are performing the analysis.
The next sheet or page should include brief content of all the major points with page numbers that are included in the report. From this page, the client will be able to know whether all relevant points are incorporated and considered in the analysis or not.
From the next page onwards, the actual analysis report of each stress system starts. Broadly the report should include the following major points:
Project Background: The project background can be included in 3-4 sentences highlighting the major points of the project. Many organizations use this as the starting point for the introduction part of the report. However, I personally do not prefer to include it.
Document Scope and Purpose: Every document must start stating the objective/ scope and purpose of the document. In this part, you can include the major system description. A typical objective is included here for your reference: “The main objective of this document is to furnish the findings of stress analysis performed on SYS-001 (Line 42”-P-YYYY-YYYY line routed from Tie-in YYYY to Tank (T-YYYY) inlet nozzle.” In a similar way, you can describe the system for which you are preparing the report.
Next, you can include a list of all abbreviations that you are going to use in the report. If you are not using abbreviated terms then this part is not required.
Now you have to include the lines which are included in that specific stress system. After including the major system lines, you can include the reference lines with the suffix REF (Ex. 18”-P-1235-REF).
Next, you have to include the names and numbers of all reference documents which are used in the analysis. Reference documents mean you should include the P&ID number with revision, line list number with revision, PMS number with revision, Equipment TAG and GA drawing number with revision, Any datasheet (PSV, Control Valve, etc.) number with revision, etc.
Assumptions and Consideration: The next part of the report is very important. Here you should mention all the considerations and assumptions if any. In a few points, you should mention all major highlights which can impact the stress system. A typical example of assumptions is shown below:
- The ambient temperature considered is 21° C.
- All systems have been analyzed for maximum and minimum design temperature cases. The operating temperature from the line list is not used in the analysis.
- Caesar II configuration file “mm. fil” is used in the analysis.
- Rigid body weights (flanges, valves, strainers, etc. as applicable) are considered from Caesar II database / Pipe Data Pro.
- Control valve and PSV weights (wherever applicable) have been assumed suitably based on judgment where vendor data is not available.
- Based on the YYYYYY project, YYYY has considered the Post Hydro test tank settlement value is assumed as 25 mm. All piping flanges have to be connected with tank nozzle flanges only after the tank hydro testing activity is finished.
- Seismic Analysis has been ignored in this stress analysis.
- Wind Analysis has not been performed as most of the lines are below 10 m elevation.
- The existing part of lines has been modeled taking a reference from the existing PDMS 3D model. We have provided sufficient flexibility for a new line for arresting maximum thermal displacements where we could not find any guides/line stop in the existing line for proper boundary condition.
Conclusions: In this section, you should write in brief the conclusions which you have reached after the analysis. A typical example is shown in the below-mentioned bullet points:
- Pipe Stresses are within the allowable limits (Refer to the attached Stress Summary Report)
- Support loads are within the acceptable limits (Refer to attached Restraint Summary Extended Report)
- Thermal Displacements and Sustained Sagging is within the acceptable limit (Refer to attached Restraint Summary Extended and Sustained displacement Reports)
- Equipment nozzle loads are qualified with Vendor Allowable Loads in GA drawing/ relevant API standard (for pumps) as applicable (Refer to Nozzle Loading Details Sheet attached)
- Supports at nodes YYY, ZZZ, and PPP are lifting in design temperature conditions. However, a separate hot sustained/lift-off file has not been made as the system is qualifying under Appendix P operating code stress check of ASME B 31.3. (Refer to attached Stress Summary Report).
- Refer to marked-up stress isometrics for any stress recommendation.
- Refer attached spring datasheets and SPS drawings for reference.
Load Cases used in Analysis: In the next section you can mention the load cases that you have considered for analysis. However, as all load cases will appear in the stress summary or restraint summary you can skip this part here.
Detailed Report Appendices: Now you are required to include the following reports from Caesar II. It is better to use an appendix for the same for proper demarcation. A typical method is shown here.
- Appendix A: Pipe Stress Analysis input echo from Caesar II
- Appendix B: Stress Summary Report from Caesar II
- Appendix C: Restraint Summary Extended report from Caesar II
- Appendix D: Sustained Displacement Report from Caesar II
- Appendix E: Nozzle load qualification report (Normally in excel sheet, However, NEMA/WRC Caesar II reports can be attached)
- Appendix F: Trunnion calculation Report
- Appendix F: Spring datasheets if any
- Appendix G: SPS drawings if any
Attachments for Reference data: In the final part you should include the final marked-up stress isometrics and reference drawings in attachment form as shown below:
- Attachment A: Marked-up stress isometrics.
- Attachment B: P&ID drawing highlighting the system marked up
- Attachment C: LDT/ Line List drawing highlighting the specific lines.
- Attachment D: Equipment GA Drawings highlighting the nozzles and relevant data.
- Attachment E: PMS
- Attachment F: Caesar II plots for the overall system look.
Briefly, the above-mentioned points are sufficient for a complete report. However, if the client insists on any additional details you have to include the same along with the above-mentioned points. Hope now you will be able to prepare a complete report of the stress systems that you are performing.