All are usually confidential and will be the property of the
owner oil company. I can explain how I would approach putting a document together
if you require.
However it might be beneficial if you can go on one of Dave’s courses (DWOP etc) or alternately attend a SPE drilling programme training event where offset review is a discussion session.
Soft cuttings may agglomerate in the annulus to form a “doughnut” ring which impedes mud flow and cuttings transport. The ring of cuttings can migrate up or down depending upon mud flow, and may lead to blocked flow lines. Restriction of cuttings flow could ultimately lead to pack-off. Tends to occur only with WBM’s.
· Use sufficient mud inhibition to avoid sticky cuttings (e.g. KCl/polymer rather than lime or gyp/PAC mud, consider high KCl or KCl/glycol muds).
· Circulate annulus clean before trips.
· Use large diameter flowlines.
· Avoid excessive ROP’s.
· Ensure good hole cleaning to prevent cuttings build-up.
· Increase in pump pressures as the annulus partially blocks.
· Reduction in cuttings flow rate, seen at the shakers.
· Increase in torque due to braking effect of mud ring.
· Decrease in ROP and hook load as mud ring acts as piston to lift the drillpipe.
· Blocked flow line/plugged shaker screens.
· Circulate annulus clean by increasing flow rate (if EMW/ECD’s limits permit). Increase size of flow lines if possible to prevent blockage. If necessary, use viscous pill to circulate clean.
· If mud ring is severe, adding detergent may help to disperse the aggregated clay making it easier to remove. If detergent is successful, maintain this in the mud system to prevent recurrence