TIE-INs Method Statement 7

[ahassan86]

To Piping Experts: I'm new to piping industry, and I would like to learn about Tie-ins between new and existing piping system. How would you suggest a method statement for Tie-ins, both cold and hot tapping starting from spools fabrication at work shop all the way to hydrostatic pressure test after erection?

Thanks guys.

 

[pennpiper]

Issues affecting all Tie-Ins:

Tie-In Planning (With suggested primary responsibility)
1. Identify each Tie-In(s) schematic location on P&ID - Process Engineer
2. Review with Piping - Process & Piping Design
3. Create a Tie-In Index (or List) with key information about each Tie-In - Piping Design & Process Engineer
4. Review with Client - Process Engineer
5. Go to the Field to locate physical point of Tie-In - Piping Design/Process
6. Meet with plant personnel and review Tie-In requirements - Piping Design, Process, Plant Operations, Safety
7. Discuss different types and configurations of Tie-Ins - Piping Design, Process and Plant personnel
8. Establish physical Tie-In location point and type - Piping Design & Plant Personnel
9. Define if the line can be shut –down, when, how long, draining, depressurize, steam-out and other safety issues - All personnel
10. Visually inspect the existing pipe. Are more extensive tests needed to determine condition and suitability for the Tie-In? - Piping Design and Plant personnel
11. Mark or tag the selected Tie-In point - Piping Design & Plant Personnel
12. Photograph the Tie-In point - Piping Design
13. Draw sketch and take all required measurements - Piping Design
14. Determine locations of all existing block valves, vents and drains - Piping Design
15. Determine the location of all existing anchors and guides - Piping Design
16. Based on selected Tie-In location and type determine if additional vents or drains will now be required - Piping Design, Plant Operations
17. Include new vents or drains (if any) on sketch - Piping Design
18. Insure that this process is followed for all Tie-Ins - All participants
19. Get plant personnel to sign off on all data collected in the field - Piping Design & Process Engineering
20. In the office modify the P&ID as required - Process Engineer
21. Convert all field sketches into appropriate production drawings (Isometrics) - Piping Design
22. Prepare a Plot Plan style “Tie-In Location Key Plan”
23. Update the Tie-In List as required - Piping Design
24. Review all Tie-Ins with Pipe Stress for effect on existing system piping and new system piping - Piping Design
25. Finalize (check, correct and approve) all Tie-In isometric drawings - Piping Design


Additional issues related to Hot Tap Tie=Ins:

The “Hot-Tap” tie-in is more complicated. There are many, many questions and issues that need to be resolved. These include:
• Will the tie-in be a plain Hot-Tap or a more complex “Stopple” tie-in?
• Will this be a single tie-in point or a multiple tie-in point?
• Will the tie-in be made with a “split-Tee” branch or an “O-Let” branch?
• Is there proper space available for the piping fittings and the valve?
• Is there proper space for the Hot-Tap machine and the Hot-Tap operators?
• What is the commodity? Is this commodity safe for doing a Hot-Tap?
• What is the operating pressure? Can the Hot-Tap machinery handle this pressure safely?
• What is the operating temperature? Can the Hot-Tap machinery handle this temperature safely?
• Can flow be maintained (required for cooling) during the cutting part of the Hot-Tap process?
• What is downstream (direction of flow) of the Hot-Tap that might be damaged by the cuttings from the Hot-Tap process?
• Has there been proper consultation with one or more “Hot-Tap” Specialty Contractors?


prognosis: Lead or Lag

 

[ripaldee]

Considering tie-in design is in place - that is, location, piping material class and valve specifications are defined. The next step is to prepare the Method Statement which comprises of P&IDs, isometric drawings, SIS, procedures [isolation, depressurization, draining, cleaning, tie-in execution (important: determine min. pipe wall thickness at tie-in weld areas), hydrotest, leak testing] and job safety analysis. It is important that your team work closely with the plant engineers, inspectors and safety during the preparation of the Method Statement.

As for hot tap, you need to supply the hot tap unit information, like UT measurements at tie-in weld areas, header information, sticker information and header operating data, required by the unit to make the hot tap calculations. PENNPIPERs inputs for hot tap requirements is richer in details. I have experience with "hot tapping" but not with "hot tapping & stopple".

Good luck to you.

 

[ahassan86]

Guys.. Thank you so much for your help

I have all the data that I need.. now I'm preparing the Method Statement.

1- Scope
2- Equipment
3- References
4- Personnel Qualification
5- Responsibilities
6- Procedure "Step by Step"
7- Safety
8- Attachments "WPSs"

I'm stuck at "6-Procedure" because, as I mentioned before, I'm a bit new to piping industry.
Tie in description:
Remove 20" 900# blind flange at end of header (Header Name) and connect new pipe spool at (Tie-In point 01) and make connection to existing 20" at (Tie-in point 02).
Material: ASTM A790 Duplex St.St.

Would you suggest a step-by-step procedure, starting from pipe spool fabrication at workshop till installing it in a/m tie-in points, including all activities and hydrotest?

Thanks guys

 

[ahassan86]

I have a preliminary proposal:

1- UT Thickness readings at Tie-In points.
2- Preparing all required equipment prior to shutdown
3- Hot Bolting before shutdown
4- Fabricating pipe spools at workshop acc. to DWGs, P&IDs, ISO.
5- Welding at workshop
6- NDT and Hyrdo-Test at workshop
7- Spools transportation to site
8- Work Permit
9- Installing permanent and temporary supports
10- Fitup at Tie-in points "flanges, fitting..."
11- Welding on site
12- NDT and Hydro-Test on site
13- Golden welds inspection
14- Flushing and cleaning
15- Removing Tempo. supports
16- Reinstatement
17- end of shutdown and back to service

feed me back on this please.
Thanks