A cycle, or down the hole and back, is the time required for the pump to move the drilling fluid in he hole.

The cycle in minutes equals the barrels of mud in the hole divided by barrels per minute.

1.

To remove with the drill bit the residual cement that normally remains in the lower section of casing and the wellbore after the casing has been cemented.

2.

To remove the settlings and cavings that are plugged inside a hollow fish (such as drill pipe) during a fishing operation.

A heavy, thick-walled tube, usually steel, used between the drill pipe and the bit in the drill stem to provide a pendulum effect to the drill stem and weight to the bit.

1.

The employee directly in charge of a drilling or workover rig and crew.

His main duty is operation of the drilling and hoisting equipment, but he is also responsible for downhole condition of the well, operation of downhole tools, and pipe measurements.

2. the supervisor of the rig crew.

The driller is responsible for the efficient operation of the rigsite as well as the safety of the crew and typically has many years of rigsite experience.

Most drillers have worked their way up from other rigsite jobs.

While the driller must know how to perform each of the jobs on the rig, his or her role is to supervise the work and control the major rig systems.

The driller operates the pumps, drawworks, and rotary table via the drillers console-a control room of gauges, control levers, rheostats, and other pneumatic, hydraulic and electronic instrumentation.

On older drilling installations, the driller also operates the drawworks brake using a long-handled lever.

Hence, the driller is sometimes referred to as the person who is “on the brake.”

A lease or a number of leases of adjoining tracts of land that constitute a unit of acreage sufficient to justify the expense of drilling a wildcat.

The cutting or boring element used for drilling.

See bit.

The operation during the drilling procedure at the point of drilling into the pay formation.

1.

Circulating fluid, one function of which is to force cuttings out of the wellbore and to the surface.

Other functions are to cool the bit and to counteract downhole formation pressure.

While a mixture of barite, clay, water, and chemical additives is the most common drilling fluid, wells can also be drilled by using air, gas, water, or oil-base mud as the drilling fluid.

2. any of a number of liquid and gaseous fluids and mixtures of fluids and solids (as solid suspensions, mixtures and emulsions of liquids, gases and solids) used in operations to drill boreholes into the earth.

Synonymous with “drilling mud” in general usage, although some prefer to reserve the term “drilling fluid” for more sophisticated and well-defined “muds.” classifications of drilling fluids has been attempted in many ways, often producing more confusion than insight.

One classification scheme, given here, is based only on the mud composition by singling out the component that clearly defines the function and performance of the fluid: (1) water-base, (2) non-water-base and (3) gaseous (pneumatic).

Each category has a variety of subcategories that overlap each other considerably.

synonyms: drilling mud, mud.

The supervisor of drilling or workover operations on a rig.

Also called a rig manager, rig supervisor, rig superintendent, or tool pusher.

A driller, a derrickman, and two or more helpers who operate a drilling or workover rig for one tour each day.

1.

A suspension of extremely fine particles in a liquid (such as colloids in a colloidal solution).

2.

Of aggregates, subdivision of aggregates.

Dispersion increases the specific surface of the particle; hence, it results in an increase in viscosity and gel strength.

The hoisting mechanism on a drilling rig.

It is essentially a large winch that spools off or takes in the drilling line and thus raises or lowers the drill stem and bit.

A tool employing tripping devices that limit tool movement from pressure either above or below the tool

A colloid or finely divided substance.

The angle at which a wellbore deviates from the vertical, expressed in degrees, as revealed by a directional survey.

Also called angle of deviation, angle of drift, and inclination.

See directional survey.