Ensure that a drill pipe strainer is ALWAYS in the pipe when pumping fluids into the well
Ensure 4 x ditch magnets are in place for extracting milled cuttings.
Prepare sweeps prior to milling operations to aid clean up.
Theoretical swarf weight estimation has been noted from whipstock supplier.
Consider inclusion of circulation sub in the string for increased hole cleaning capability (especially if milling 7” liner – position circulation at top of liner activate and sweep at high flow rate).
Include a non ported float in the BHA to prevent plugging the mill with swarf.
Include string magnets in any contingency clean up BHA (note: do not remove transit tape as it makes it easier to clean).
Ensure there is sufficient spaceout to allow milling operation to be performed without connection breaks.
Confirm maximum allowable torque according to drill pipe connections.
Highlight the safety practice of using correct PPE when handling metal cuttings and ensure all personnel are wearing suitable gloves when handling metal swarf.
Particular attention should be paid to ensuring that good hole cleaning practices are observed during the milling phase. These practices include regular sweeps and use of ditch magnets.
Maintaining effectiveness of ditch magnets is extremely important. Prior to removing a magnet from the ditch for swarf removal and weighing, first insert a clean magnet.
Clean magnets and collect swarf for weight measurement.
Record total weight of swarf retrieved (ditch magnets, junk basket & string magnets) since start of milling and compare with theoretical milled steel weight.
Sweeps should follow the Baroid Fluids recommendations for consistency, volume, and frequency. Record swarf weight for each sweep.
The Barolift pills should be caught at surface and disposed of to avoid mixing with new mud.
Barolift is mixed through the hopper into a separate volume of circulating fluid. After mixing, circulate (15-30 min) through the hopper’s venturi to disperse the product into the fluid and prevent clusters of product in the fluid.
Do not work mills in area of whipstock tip for any prolonged period (max 30 mins).
Do not sit in the same place on the whipstock face for prolonged period – mill may eat into whip face.
Estimate and record percentage of cement against formation from shakers.
Inspect and record mill wear.
When running follow up drilling assembly – orient to window exit and slide through without circulation
