kick_detection

Kick Detection n

Kick Detection Equipment.

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Kick Detection (while drilling and while tripping).

Kick Detection At the end of this section you should be able to: n n

Identify the minimum kick detection equipment. Describe practices to detect a kick.

Kick Detection Once a kick has occurred, the severity of the subsequent well control operations is dependent on the size of the influx and the degree of underbalance. Early recognition of an influx and rapid shut in are the key to effective well control.

Kick Detection Equipment: Every rig should have at a minimum the following equipment in good working order: n

Pit Volume Totalizer (PVT system).

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Delta Flow Meter.

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Trip Tank Indicator.

Kick Detection Equipment n

Pit Volume Totalizer (PVT system): electronic or analogue pit level indicator to measure mud tanks levels, a display for key information, and the ability to give visual and audible warnings. The display shall be visible to the driller.

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Delta Flow Meter: gain / loss measurements equipped with two adjustable alarm thresholds on the display module for visual an audible warning.

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Trip Tank: is a low volume (100 bbls max.) calibrated tank, which can be isolated from the remainder of the surface drilling fluid system and used to accurately monitor the amount of fluid going into or coming from the well. The primary use of the trip tank is to measure the amount of drilling fluid required to fill the hole while pulling pipe to determine if the drilling fluid volume matches pipe displacement.

Kick Detection while Drilling At all times while drilling, alertness is to be maintained in order to identify as early as possible any warning sign or evidence of a kick. The following indicators of potential formation fluid influx into the wellbore should be flow checked: Drilling Break: is a significant increase in the rate of penetration by the drill bit. All drilling breaks must be flow checked. It is recommended to carry out one bottom’s up circulation after a drilling break. Increase in Return Flow: the differential flow indicator should offer visual and audible alarms. An increase in return flow is often the first indication of an influx. Pit Level Increase: an increase in pit level can be an indicator that an influx of formation fluid has occurred. Pump Pressure Decrease / Pump Stroke Increase: when an influx enters the wellbore, the fluid column in the annulus becomes lighter, unless the influx is denser than the drilling fluid. The mud in the drill pipe begins to "U-Tube" and a slight pressure drop may be observe which may or may not be accompanied by an increase in pump strokes.

Kick Detection while Tripping Influx into the wellbore will cause inappropriate hole fill-up. The use of the trip tank and the trip sheets will highlight any deviation from expected hole fill volumes. Any deviation must be investigated and a flow check carried out. If the flow check is positive, the well must be shut-in immediately. A negative flow check does not mean that there is no influx: – Small influx swabbed in, not enough to create an underbalance situation. Although it may migrate, the volume changes are very small to be detected at surface while flow checking. – Horizontal well, a swabbed kick confined in the horizontal section will not cause any additional influx. – OBM used, the gas will go into solution in the OBM and the well may appear to be static.