Hot tapping work is a critical work especially in process industry such as pharmaceutical plants, petrochemical plants, offshore platform and FPSO. Hot tapping work is the connection of branch line piping to existing piping that contains live products such as gas or oil under pressure. More information on hot tap operation and detail, refer to this site. In this post, I would suggest the WBS and activities for a hot tap detail construction schedule.
Sample WBS are as follows;
1 Area
1.1 Work pack
1.1.1 Tie-in No
1.1.1.1 Off site Fabrication
1.1.1.2 Preliminary Activities
1.1.1.3 Execution
1.1.1.4 Post Activities
Activities such as fabrication of hot tap (split tee type or stub type), blasting and painting, delivering to site are of off site fabrication WBS.The preliminary on site construction activities before hot tap operation are as follows;
- Erect spark containment habitat (to avoid fire hazards)
- Perform lamination check/UT test/MPI test (hot tap preparation work)
- Perform ovality on hot tap location
- Submitted UT test/MPI result to consultant/client for review
- Approved to weld on hot tap location
- Hydro test hot tap valve priority to drilling work
- Remove walkway/support for hot tap machine access (this activity may or may not exist, depends on nature of scope)
- Hot work permit received
On site execution activities and work steps are as below;
- Operation line check/gas test
- Crane and welding machine into position (crane is not required if the hot tap size is less than 6" and on above ground)
- Clamp split tee for 14” hot tap
- Check with operation on flow parameter
- Fit-up/tack weld split tee on existing pipe
- Fit-up inspection (contractor/consultant/client)
- Welding (root run on branch section)
- Welding (root run on longitudinal section)
- NDT for both roots (MPT test)
- Full fillet welding on circumstance existing pipe
- Cap butt welds
- Pneumatic test on comp pad
- Install hot tap valve/blind for hydro test
- Hydro test hot tap nozzle and valve
- Inspect hot tap machine prior to drilling operation
- Hot tap drilling by tapping contractor
- Close hot tap valve
- Depressurise and drain the tapping
- Remove hot tap cutter
- Install vented blind
Note : Welding type of activities 7,8 and 10 would be different if hot tap fitting is not a split tee. In this post, Hot tap fitting is split tee type.
Post activities after drilling operation are
- 1st PSSR by contractor/consultant/client clear punches items
- Touch-up painting on hot tap nozzle
- House keeping
Sample hot tap construction schedule is shown as below.
You can also download this schedule
thanks
ReplyDeleteCould you please post a sample WBS and Schedule for the Transportation and Load-out of WHP structures like topsides and jackets? thanks
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