upload
Schlumberger Limited
Industria: Oil & gas
Number of terms: 8814
Number of blossaries: 0
Company Profile:
To prevent, arrest or slow down any action. For example, one can inhibit a corrosion process, such as by coating drillpipe with amine films to arrest pipe corrosion in air. In drilling fluids, the terms inhibit, inhibition and inhibitive mud system refer to arresting or slowing the hydration, swelling and disintegration of clays and shales.
Industry:Oil & gas
To pump fluid through the whole active fluid system, including the borehole and all the surface tanks that constitute the primary system.
Industry:Oil & gas
To prepare a well to be closed permanently, usually after either logs determine there is insufficient hydrocarbon potential to complete the well, or after production operations have drained the reservoir. Different regulatory bodies have their own requirements for plugging operations. Most require that cement plugs be placed and tested across any open hydrocarbon-bearing formations, across all casing shoes, across freshwater aquifers, and perhaps several other areas near the surface, including the top 20 to 50 ft (6 to 15 m) of the wellbore. The well designer may choose to set bridge plugs in conjunction with cement slurries to ensure that higher density cement does not fall in the wellbore. In that case, the bridge plug would be set and cement pumped on top of the plug through drillpipe, and then the drillpipe withdrawn before the slurry thickened.
Industry:Oil & gas
To plug the wellbore around a drillstring. This can happen for a variety of reasons, the most common being that either the drilling fluid is not properly transporting cuttings and cavings out of the annulus or portions of the wellbore wall collapse around the drillstring. When the well packs off, there is a sudden reduction or loss of the ability to circulate, and high pump pressures follow. If prompt remedial action is not successful, an expensive episode of stuck pipe can result. The term is also used in gravel packing to describe the act of placing all the sand or gravel in the annulus.
Industry:Oil & gas
To place the male threads of a piece of the drillstring, such as a joint of drillpipe, into the mating female threads, prior to making up tight.
Industry:Oil & gas
To mix with water and allow to react or yield in the water before use. Prehydrating is a common technique for incorporating bentonite in cement slurry or drilling mud. Prehydration may also be done for convenience in cementing operations to allow mixing of water containing the additives with powdered neat cement. Additives also may be prehydrated with mix water to avoid dry-blending the additives with cement.
Industry:Oil & gas
To part or break the drillstring downhole due to either fatigue or excessive torque.
Industry:Oil & gas
To place a stand of drillpipe in the derrick when coming out of the hole on a trip. The rig crew racks back pipe after the stand is unscrewed from the rest of the drillstring. The floor crew then pushes the lower part of the stand away from the rotary table to a position on one side of the vee-door. While the floor crew is pushing the pipe, the derrickman gets ready to pull the top of the stand over into the fingerboards. Once the rig crew has the pipe in the correct location, the driller slacks off on the drawworks, allowing the stand to rest on the drillfloor. This takes weight off of the elevators previously supporting the pipe at the top, so the derrickman can then unlatch the elevators and pull the top of the pipe into the fingerboards for storage. Modern rig designs have automated pipe-handling equipment that moves the pipe. When tripping the pipe out of the hole, racking back pipe may occur every two to five minutes for hours at a time.
Industry:Oil & gas
To make ready for use. Equipment must typically be moved onto the rig floor, assembled and connected to power sources or pressurized piping systems.
Industry:Oil & gas
To forcibly pump fluids into a formation, usually formation fluids that have entered the wellbore during a well control event. Though bullheading is intrinsically risky, it is performed if the formation fluids are suspected to contain hydrogen sulfide gas to prevent the toxic gas from reaching the surface. Bullheading is also performed if normal circulation cannot occur, such as after a borehole collapse. The primary risk in bullheading is that the drilling crew has no control over where the fluid goes and the fluid being pumped downhole usually enters the weakest formation. In addition, if only shallow casing is cemented in the well, the bullheading operation can cause wellbore fluids to broach around the casing shoe and reach the surface. This broaching to the surface has the effect of fluidizing and destabilizing the soil (or the subsea floor), and can lead to the formation of a crater and loss of equipment and life.
Industry:Oil & gas