Coiled Tubing Glossary...

Waiting On Cement: pertaining to or during the time when drilling or completion operations are suspended so that the cement in a well can harden sufficiently; often abbreviated WOC.

Water: The standard fluid to which all others are compared.

Weak Link: A description of the shear sub utilized to pull off the tool string when stuck downhole. Two types are utilized in Stiff Wireline, either the shear pin type in the SWBPV or the collet release used in the TRT. See above.

Weight Bar: A heavy weight or bar placed near the BHA. The bar provides weight so that the tools will lower properly into the well. Also called sinker bars or stem.

Weight Indicator: An instrument that shows the weight of a string of pipe suspended from the elevators.

Weighted Slurry: slurry to which a weighting material, such as hematite has been added to the blend to make the slurry heavier than normal.

Weighting Materials: A material with a specific gravity greater than that of cement, used to increase the density of drilling fluids or cement slurries.

Well Control Component, Annular Type: A device which can form a seal in the annular space around any object in the wellbore or upon itself. Compression of a reinforced elastomer packing element by hydraulic pressure effects the seal.

Well Control Component, Ram Type: A device designed to form a seal on the well bore with or without coiled tubing in the well. The equipment can use one set of blind rams, shear rams, slip rams or pipe rams to effect the required seal arrangement of the equipment, an/or existing well conditions. Combination shear/seal and pipe/slip rams are available.

Well Control Equipment Drill: A training procedure to ensure that coiled tubing personnel are familiar with correct operating practices to be followed in the use of well control equipment for blowout prevention.

Well Control Stack: An integral body or an assembly of well control components including ram-type BOPs, annular type BOPs, spools, valves, and nipples connected to the top of the wellbore to control well fluids.

Wellbore: The hole that makes up the well. A wellbore may be cased, open or a combination of both.

Wellhead: The equipment used to maintain surface control of the well.

Wettability: The relative affinity between individual grains of rock and each fluid that is present in the spaces between the grains. If oil and water are both present, most often the water is in contact with the surface of each grain, and the rock is called water wet. However if the oil contacts the surface, the rock is oil wet.

Wetting: The adhesion of a liquid to the surface of a solid.

Whipstock: a long, steel casing that uses an inclined place to cause the bit to deflect from the original borehole at a slight angle.

Wiper Plug: A rubber-bodied, plastic or aluminum cored device used to separate cement and drilling fluid. Also serves to wipe drilling mud and cement from the inside of casing during cementing operations.

WOB: An abbreviation for Weight On Bit, i.e., the force transmitted to the bit through the CT weight and the injector head. Too little WOB leads to excessive bit wear per foot of penetration and excessive WOB will cause a Stall and/or cleaning problems. The optimum WOB is one that enables DMUR to take place keeping the CT pressure below the Stall pressure.

Please inform ICoTA to add a glossary term.