Slot Recovery

24 September 2012 Slot recovery, Well is vertical We have the following:

• 30” conductor set at 300 ft MD (200 ft below sea bed) (ID of Conductor 28”)
• 13 â…œ” set at 4500 and cemented to surface. (13â…œ” 68 LB/FT)
  
• 9 ⅝” CSG set at 8500 ft MD, cemented to surface.
  

The plan to sidetrack the well below the 30” conductor shoe, drill new hole 17"” hole, set new 13â…œ”. In fact we did so far 8 wells by milling both casing (9⅝" and 13â…œ")from surface to 50 ft below the 30” conductor shoe, but we are still looking to improve the cost because each job of milling is costing us 2.5MM$ to clear enough room below the conductor shoe.

The milling also took 15 days to mill ±300 ft of 13â…œ” and 9 ⅝” casing. We found the above method is costly (money and days). Next year one of the wells will be vertical and we need to do some is different and we need your advice.

1. We will remove the well head after abandonment the old hole.
2. Cut all casing (9⅝” and 13â…œ”casing) to 50 ft below the conductor shoe.
3. the clearance between the 30” conductor and 13â…œ” CSG is enough to wash over the cement (drill the cement) ,we will use especial core head or special rotary wash pipe shoe
4. We will put 16” casing or 18⅝” as extension above the bit.
5. We will continue drilling to 10 ft below the conductor shoe.
6. run with 9⅝” CSG spear and latch into CSG and Pull the casing and L/D same.

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May be the Casing is not centric inside the 30” Conductor, so will make drilling the cement with rotary shoe  very difficult. Therefore Can we use 3â…›” bit with 3"” drill pipe or 2⅞” to clean the cement in the biggest side of the clearance between the 30” conductor & 13â…œ” casing.

7 Answer(s)

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