HOT TAP 9

[MB2010]

I am looking for a document that gives clear guidlines on Hot Tapping, I have reviewed API RP 2201 but didn't find much details as to where/which services to allow for Hot Tap and whether it should be considered a permanent or temporary solution,

 

[pennpiper]

"where/which services to allow for Hot Tap and whether it should be considered a permanent or temporary solution?
Where? In the information below there is some information on this but the simple answer is, anywhere you can get the Hot-Tap machine you can do a Hot-Tap.

Which services to allow Hot-Taps? Based on my own past experience you can "Hot-Tap" virtually any commodity subject to the approval of the facility (refinery, Chemical Plant, etc) Safety Department.

Permanent or temporary? This depends on the needs of the connection. Once you make a Hot-Tap it is there but at some point in the future during a full shut-down you could dismantle and blind off the connection.

How to do a Tie-In

There are two basic conditions that exist when doing a “Tie-In.” The first condition is when a Tie-In must be made and the line can be shutdown and made safe for welding or other work. This is called a “Cold” tie-in. The second condition is when a Tie-In must be made and the line cannot be shutdown. This is called a “Hot-Tap” tie-in.

Some Hot-Tap tie-ins also require a procedure called “Stopple”. This is where a second Hot-Tap is made downstream of the first one. The flow is routed through the first tie-in while an articulated plug is inserted into the second Hot-Tap to blank off the flow. Various kinds of work can then be done to the remaining pipe.

The “Cold” tie-in is simple to design and install. With only a few exceptions you can handle them the same as you would for any new piping. The exceptions include:
• Make a proper survey of the condition of the existing pipe material. Is it too corroded to join the new pipe to?
• The existing line can be shut down but can the environment around the existing pipe be made safe for any required welding?

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 tie-in 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?

Issues for all tie-ins:
• Has Process Engineering reviewed and approved the location and type of tie-in?
• Has Plant Operations reviewed and approved the location and type of tie-in?
• Has the Installation Constructor reviewed and approved the location and type of tie-in?
• Has the tie-in location been tagged for easy and proper identification?
• Have the proper drawings been prepared and checked?
• Has the proper material been ordered?

There are a number of issues that come up as a result of your question.
Example:
• Are you sure you will be doing a “Hot-Tap” or will you be doing a "Cold" tie-in?
• Who are you in the overall picture of this Tie-in? Are you the Client? The primary engineering company planning the Tie-in? Or are you the Mechanical Contractor who will be overseeing the actual Tie-in? Or are you someone else in the grand scheme of things?
• What is the line size and wall schedule of the tie-In?
• What is the commodity normally in the line?
• How far to the closest valves up stream and downstream of the Tie-in Point?
• Can the upstream and downstream piping be drained and steamed out?

Tie-In Planning Who is involved?
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 the 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

Tie-In List (For all multiple Tie-In Projects)
A "Tie-In" List will normally have a Title Block area and a Tie-In List “Data" area.
Note: [piping] indicates responsibility

The Title Block area should have the following:
- Title (Example- "Piping Tie-In List")
- Document Number
- Sheet No.
- Project Name
- Project Number
- Unit Number
- Issue Date
- Issue Description
- Prepared By (name)
- Checked By (name)
- Approved By (Name)

A Tie-In List Data area should (or may) have the following:
For the new line: [indicates responsibility]
- Tie-In No. [piping]
- P&ID No. [piping]
- Piping Plan No. (new) [piping]
- Tie-In Iso. No. (if different than Line Number)[piping]
- Line No. [piping]
- Conn. Type [piping]
- Commodity [piping or process]
- Oper. Press. (this should be the same as the existing line so you do not need it twice)[piping or process]
- Oper. Temp. (this should be the same as the existing line so you do not need it twice) [piping or process]
- Test Media [piping]
- Test Press. [piping]
- NDE Req'd. [piping]

For existing line being tied into:
- Exist. Piping Plan [piping]
- Exist. Line No. [piping]
- Exist P&ID [piping]
- North Coord. [piping]
- East (or West) Coord. [piping]
- Center line Elev. [piping]

Construction:
- Pre-weld Inspection [welding engineer]
- Welding Comp/tested [construction]

Schedule Data:
- Req'd Complete Date [Client]
- Schedule Shut-down [Client]
- Completion Client Sign-Off [Client]

Other:
- Remarks [all groups]

 

[zdas04]

Penpiper,
Dang I hope that was a cut and paste.

David

 

[MiketheEngineer]

Ditto that --- does Pennpiper need a job?? I bet I can find him one!! Or write a book or teach a class!!

 

[pennpiper]

zdas04,
Yes it was a "Cut & Paste" from a Hot-Tap question I had some time ago.

MiketheEngineer
No I do not "Need" a job but I am do consider and accept consulting situations when they arise.

Yes I did write a book,
"Piping Engineering Leadership for Process Plant Projects"
You can find it on amazon.com

and

Yes I have taught a lot of classes, From beginner, basic piping to Piping Leadership/Supervision

 

[gearguru]

A star for pennpiper

 

[flash3780]

I was curious after reading the above so I looked and found this video explaining hot tapping. Neat stuff.

http://www.youtube.com/watch?v=GXtBLjoirfs

 

[pennpiper]

flash3780,
Thank you for the fine video. It shows the process of the more complex "Stopple" & bypass for the addition of the new valve.

The common Hot-Tap for an ordinary branch does not need everything that the Stopple needs.

 

[Spud6414]

This is very neat topic and very nice video. Thanks to all on this.

Spud says; Meticulous effort and willingness to learn are honorable traits.

 

[IFRs]

API 653 also has a section on hot tapping

 

[pennpiper]

IFRs,

API 653, Tank Inspection, Repair, Alteration, and Reconstruction.

Does this "section" address the addition of a new nozzle to an API 650 Tank full of Crude Oil or Jet Fuel?

 

[IFRs]

PenniPiper - Section 9.14 is devoted to hot taps on an API 650 tank (regardless of the fluid), when it can and can not be done, procedure, minimum shell thicknesses, etc. It's only 4 pages and one page is a figure. It references API 2201 also.

 

[MB2010]

Thanks everyone for the info.