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HOT TAP 9
- Thread starter MB2010
- Start date
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8
- #2
"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]
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]
MiketheEngineer
Structural
Ditto that --- does Pennpiper need a job?? I bet I can find him one!! Or write a book or teach a class!!
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
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
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1
- #7
I was curious after reading the above so I looked and found this video explaining hot tapping. Neat stuff.
- Thread starter
- #13
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