tie- in procedure

8/9/2019 Tie- In Procedure

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Questions on this subject have come up on other Piping related forums before. The following

is my answer to them. Others out there are invited to add other items that may have beenfound to be of importance their individual projects.

Piping Tie-Ins (Revision #!"

Cold Tie-In Procedure

The question

I have a Piping Fabrication and Installation Procedure. Is this procedure the same as tie-in procedure? If they are different, does anybody have a cold tie-in procedure?

y answer$

There are a number of %uestions that come up as a result of your %uestion.

&'ample$

• hat is covered in the Piping )abrication and *nstallation Procedure+

• ,re you sure you will be doing a -cold- tiein+

• ho are you in the overall picture of this Tiein+ ,re you the /lient+ The primary

engineering company planning the Tiein+ Or are you the echanical /ontractor who

will be overseeing the actual Tiein+ Or are you someone else in the grand scheme of

things+

•

hat is the line si0e and wall schedule of the tie*n+

• hat is the commodity normally in the line+

• 1ow far to the closest valves up stream and downstream of the Tiein Point+

• /an the upstream and downstream piping be drained and steamed out+

Tie-In Planning

. *dentify each Tie*n(s" schematic location on P2*3 Process &ngineer

4. Review with Piping Process 2 Piping 3esign

5. /reate a Tie*n *nde' (or 6ist" with 7ey information about each Tie*n Piping 3esign

2 Process &ngineer

!. Review with /lient Process &ngineer

8. 9o to the )ield to locate physical point of Tie*n Piping 3esign:Process



;. eet with plant personnel and review Tie*n re%uirements Piping 3esign< Process<Plant Operations< =afety

>. 3iscuss different types and configurations of Tie*ns Piping 3esign< Process and

Plant personnel

?. &stablish physical Tie*n location point and type Piping 3esign 2 Plant Personnel

@. 3efine if the line can be shut Adown< when< how long< draining< depressuring< steam

out and other safety issues ,ll personnel

B.Cisually inspect the e'isting pipe. ,re more e'tensive tests needed to determine

condition and suitability for the Tie*n Piping 3esign and Plant personnel

.ar7 or tag the selected Tie*n point Piping 3esign 2 Plant Personnel

4. Photograph the Tie*n point Piping 3esign

5.3raw s7etch and ta7e all re%uired measurements Piping 3esign

!.3etermine locations of all e'isting bloc7 valves< vents and drains Piping 3esign

8.3etermine the location of all e'isting anchors and guides Piping 3esign

;.Dased on selected Tie*n location and type determine if additional vents or drains will

now be re%uired Piping 3esign< Plant Operations

>. *nclude new vents or drains (if any" on s7etch Piping 3esign

?. *nsure that this process is followed for all Tie*ns ,ll participants

@.9et plant personnel to sign off on all data collected in the field Piping 3esign 2Process &ngineering

4B. *n the office modify the P2*3 as re%uired Process &ngineer

4./onvert all field s7etches into appropriate production drawings (*sometrics" Piping

3esign

44.Prepare a Plot Plan style -Tie*n 6ocation Eey Plan-

45.Fpdate the Tie*n 6ist as re%uired Piping 3esign

4!.Review all Tie*ns with Pipe =tress for effect on e'isting system piping and new

system piping Piping 3esign

48. )inali0e (chec7< correct and approve" all Tie*n isometric drawings Piping 3esign

, -Tie*n- 6ist will normally have a Title Dloc7 area and a Tie*n 6ist -3ata- area.Gote$ HpipingI indicates responsibility



The Title Dloc7 area should have the following$

Title (&'ample -Piping Tie*n 6ist-" 3ocument Gumber

=heet Go. Project Game

Project Gumber Fnit Gumber *ssue 3ate

*ssue 3escription

Prepared Dy (name" /hec7ed Dy (name"

,pproved Dy (Game"

, Tie*n 6ist 3ata area should (or may" have the following$)or the new line$ Hindicates responsibilityI

Tie*n Go. HpipingI P2*3 Go. HpipingI

Piping Plan Go. (new" HpipingI

Tie*n *so. Go. (if different than 6ine Gumber"HpipingI 6ine Go. HpipingI /onn. Type HpipingI

/ommodity Hpiping or processI Oper. Press. (this should be the same as the e'isting line so you do not need it twice"

Hpiping or processI Oper. Temp. (this should be the same as the e'isting line so you do not need it twice"

Hpiping or processI Test edia HpipingI

Test Press. HpipingI G3& Re%Jd. HpipingI

)or e'isting line being tied into$ &'ist. Piping Plan HpipingI

&'ist. 6ine Go. HpipingI &'ist P2*3 HpipingI

Gorth /oord. HpipingI &ast (or est" /oord. HpipingI

/enter line &lev. HpipingI

/onstruction$

Preweld *nspection Hwelding engineerI elding /omp:tested HconstructionI

=chedule 3ata$

Re%Jd /omplete 3ate H/lientI =chedule =hutdown H/lientI

/ompletion /lient =ignOff H/lientI

Other$ Remar7s Hall groupsI

How to do a Tie-In



The question:

hat methods and techniques are used to brea! into pipelines? I !no" that the easiest "ay "ould be to a blind flanged tie-in point or if a line is to be modified post a flange#valve then

it is easiest to ma!e a ne" spool bet"een t"o flanges. $y question relates to "hen youhave to put a ne" tie-in into a pipeline and the above isn%t viable, i.e. there is no option but

to brea! into the line. I told one option on a gravity drain line for e&ample "ould be to cutthe line then put a bung into the pipe to stop drains bac!ing up, ma!e up the ne" spoolthen "eld them bac! together. ith piping I am a"are it isn%t al"ays as simple as this as

sometimes "elding isn%t an option either. I !no" you could also use an o%let for branching.

y answer$

To start< letJs correct the terminology. The term you used -to brea7 into (a" pipeline- iscalled a -Tie*n- by more than @8K of the piping profession. The balance of the people use

-TiePoint- or some other term. Regardless of which of these terms you use they mean thesame.

There are two basic conditions that e'ist when doing a -Tie*n.- The first condition is when aTie*n must be made and the line can be shutdown and made safe for welding or otherwor7. This is called a -/old- tiein. The second condition is when a Tie*n must be made and

the line cannot be shutdown. This is called a -1otTap- tiein.

=ome 1otTap tieins also re%uire a procedure called -=topple-. This is where a second 1otTap is made downstream of the first one. The flow is routed through the first tiein while an

articulated plug is inserted into the second 1otTap to blan7 off the flow. Carious 7inds ofwor7 can then be done to the remaining pipe.

The -/old- tiein is simple to design and install. ith only a few e'ceptions you can handlethem the same as you would for any new piping. The e'ceptions include$

L a7e a proper survey of the condition of the e'isting pipe material. *s it too corroded to join the new pipe to+

L The e'isting line can be shut down but can the environment around the e'isting pipe be

made safe for any re%uired welding+

The -1otTap- tiein is more complicated. There are many< many %uestions and issues thatneed to be resolved. These include$

L ill the tiein be a plain tiein or a more comple' -=topple- tiein+

L ill this be a single tiein point or a multiple tiein point+

L ill the tiein be made with a -splitTee- branch or an -O6et- branch+

L *s there proper space available for the piping fittings and the valve+

L *s there proper space for the 1otTap machine and the 1otTap operators+

L hat is the commodity+ *s this commodity safe for doing a 1otTap+



L hat is the operating pressure+ /an the 1otTap machinery handle this pressure safely+

L hat is the operating temperature+ /an the 1otTap machinery handle this temperaturesafely+

L /an flow be maintained (re%uired for cooling" during the cutting part of the 1otTap

process+

L hat is downstream (direction of flow" of the 1otTap that might be damaged by the

cuttings from the 1otTap process+

L 1as there been proper consultation with one or more -1otTap- =pecialty /ontractors+

*ssues for all tieins$

L 1as Process &ngineering reviewed and approved the location and type of tiein+

L 1as Plant Operations reviewed and approved the location and type of tiein+

L 1as the *nstallation /onstructor reviewed and approved the location and type of tiein+

L 1as the tiein location been tagged for easy and proper identification+

L 1ave the proper drawings been prepared and chec7ed+

L 1as the proper material been ordered+

tie- in procedure

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