Oil and Gas Terms Beginning with “C” — Page 4

Casing hardware (also called casing accessories, running equipment, or shoe track assembly components in WCSB well construction and cementing engineering) is the collective term for the non-pipe mechanical components… Read more →

Casing joint (also called a joint of casing, a casing stick, or a single in WCSB well construction and casing running operations) is a single length of steel pipe with a threaded pin on one end and a threaded coupling… Read more →

A casing patch is a tubular steel liner section run inside a damaged, corroded, or perforated interval of production casing and set with mechanical or hydraulically expanded seals at both ends to bypass the compromised… Read more →

A casing point is the planned depth at which a casing string will be set and cemented during the drilling of a well, selected by the drilling engineer to provide structural support and zonal isolation at a depth where… Read more →

Casing pressure is the pressure measured at the wellhead on the annular space between the production tubing and the innermost casing string (the tubing-casing annulus, or A-annulus), or more broadly any pressure… Read more →

Casing reciprocation is the practice of moving the casing string up and down in the wellbore during primary cementing operations, with a controlled stroke of 1 to 3 metres applied repeatedly at a rate of 5 to 15 strokes… Read more →

A casing roller is a mechanical device fitted to a casing string that contacts the borehole wall, casing, or liner during running operations to reduce drag and torque, provide standoff between the casing OD and the… Read more →

A casing scraper is a downhole tool run on a workstring, coiled tubing, or drill string inside an existing casing string to mechanically remove scale, cement, corrosion products, paraffin, asphaltene deposits, and other… Read more →

A casing shoe is the steel fitting threaded onto the bottom joint of a casing string that guides the casing into the wellbore during running operations, provides a smooth rounded or tapered leading edge that prevents… Read more →

A casing shoe test is a pressure test performed on the open-hole formation immediately below a newly drilled-out casing shoe, conducted by closing the blowout preventer, pumping a measured volume of drilling fluid down… Read more →

A casing spool is a flanged steel wellhead component bolted between the casing head (the bottom wellhead component welded to the conductor or surface casing) and the next wellhead component above it, containing an… Read more →

A casing string is the full assembled length of steel pipe sections (joints) threaded together and run as a single continuous tubular string from the wellhead to the planned setting depth in the wellbore, where it is… Read more →

A casing swage is a solid steel mandrel with a tapered or rounded leading nose and a cylindrical body machined to a specific outside diameter that is run into a deformed, buckled, or collapsed casing string on a… Read more →

A casing test is a pressure test applied to a casing string after it has been run and cemented in the wellbore, designed to verify that the casing body, connections, and cement sheath provide a pressure-tight barrier… Read more →

A casing thread is the machined helical groove cut into the pin end (male) and box end (female) of casing pipe joints that, when made up to the correct torque, creates a pressure-tight mechanical connection between… Read more →

A casing valve is a manually operated or remotely actuated shut-off valve installed on the side outlet port of a casing head or casing spool at the wellhead, providing isolation of the casing annulus from the surface… Read more →

Casing inspection log (also called an electromagnetic inspection log, casing corrosion log, mechanical caliper survey, or downhole casing integrity survey in WCSB well integrity and abandonment engineering) is a suite… Read more →

A casing potential profile (also called a casing potential survey or pipe-to-soil potential log) is a wireline measurement of the electrochemical potential between the steel casing string and a reference electrode drawn… Read more →

A casinghead (also spelled casing head, and sometimes called a casing head spool or surface casing head) is the lowermost permanent wellhead component, welded or threaded to the top of the conductor casing or surface… Read more →

A cat line (also called a catline, and derived from the older term "cathead line") is a rope or wire line rigged from the rig floor to the cathead drum on the drawworks, used to hoist light loads on the rig floor such… Read more →

Cataclastic rock is any rock that has been mechanically deformed by brittle fracturing, grain crushing, and frictional sliding along a fault or shear zone without significant recrystallization or chemical alteration,… Read more →

Catagenesis is the stage of thermal maturation during which buried organic-rich sedimentary rock (source rock) undergoes thermally driven cracking reactions that convert solid kerogen into liquid petroleum and natural… Read more →

A cathead is the rotating drum or spool mounted on the end of the drawworks shaft on a drilling or workover rig that serves as the power source for auxiliary hoisting operations on the rig floor, rotating continuously… Read more →

Cathodic protection is an electrochemical corrosion control technique that suppresses the oxidation reactions on a metal structure by making the structure the cathode of an electrochemical cell, either by connecting it… Read more →

A cation is a positively charged ion formed when an atom or molecule loses one or more electrons, acquiring a net positive charge equal to the number of electrons lost, and in the context of Western Canada Sedimentary… Read more →

Cation exchange capacity (CEC) is the total quantity of positively charged ions that a clay mineral or organic matter surface can hold in an exchangeable form at a given pH, expressed in milliequivalents per 100 grams… Read more →

Cation exchange capacity of drilling fluid (CEC-2, also expressed as the mud methylene blue test or mud MBT value) is the measure of the total reactive clay and organic colloid content of a circulating drilling fluid,… Read more →

A catline is the rope or wire rope rigging system installed on a drilling or workover rig that uses the cathead drum as its power source to perform auxiliary hoisting and positioning tasks on the rig floor, consisting… Read more →

The catwalk is the inclined ramp or horizontal staging area on a drilling or workover rig that connects the pipe rack or pipe laydown area at ground level to the rig floor elevated on the substructure, serving as the… Read more →

The caustic extraction test is the standard analytical procedure used on oil-based and synthetic-based drilling fluid systems to measure the concentration of excess lime (calcium hydroxide, Ca(OH)2) dissolved in the… Read more →