Oil and Gas Terms Beginning with “R” — Page 6

What Is Ring Resistivity? Ring resistivity is a logging-while-drilling (LWD) resistivity measurement made by a toroidal coil antenna array oriented perpendicular to the tool axis, producing a measurement that averages… Read more →

Ringworm corrosion is a specific type of localized bimetallic (galvanic) corrosion that develops on oilfield tubular goods (drillpipe, casing, production tubing) in a distinctive ring-shaped pattern located several… Read more →

A rising bubble apparatus is a laboratory instrument that determines the minimum miscibility pressure (MMP) of a gas-oil system by injecting a small gas bubble into a sight glass capillary tube filled with crude oil at… Read more →

What Is Rock? Rock is a naturally occurring solid aggregate of one or more minerals, organic matter, or volcanic glass that forms the Earth's crust and provides the physical medium within which petroleum systems develop… Read more →

Rock mechanics is the branch of mechanics concerned with the mechanical behavior of rock and rock masses, including their deformation, failure, and response to applied stresses and pore fluid pressures, applied in… Read more →

Rock properties are the physical characteristics of reservoir rock that determine its ability to store hydrocarbons and to allow those hydrocarbons to flow through it toward a wellbore. The two master properties are… Read more →

In reservoir characterization, rock types are groupings of rock that share a common set of petrophysical characteristics, chiefly those governing how fluids move through the rock and how much fluid the rock can store.… Read more →

Rod elevators are lightweight steel tools designed to grip and lift the sucker rod string during workover operations on artificially lifted wells, primarily those producing through reciprocating beam pumps in WCSB heavy… Read more →

What Is a Rod Pump in Oil and Gas? A rod pump , formally called a sucker rod pump , is a reciprocating positive-displacement pump used to lift oil from a wellbore to surface by converting the up-and-down motion of a… Read more →

An assembled length of sucker rods used to connect and power a rod pump with the reciprocating power source at surface. Read more →

A rod unit is a lightweight, purpose-built well servicing rig engineered specifically for running and retrieving sucker rod strings and downhole rod pumps used in beam-pumping artificial lift systems. Rod units are… Read more →

To roll a tank in oilfield operations is to thoroughly mix or agitate the contents of a storage tank, production separator, or treating vessel by circulating fluid through the tank using a pump, jet mixer, or gas… Read more →

A roll line is a thin, perforated pipe installed around the inner circumference of a storage or treating tank whose job is to agitate the tank contents by discharging fluid in a controlled, sweeping pattern that sets… Read more →

What Is a Roller Cone Bit? A roller cone bit (also called a tricone bit) is a rotary drilling bit with three conical rolling cutters — the cones — that crush, chip, and gouge rock as the bit rotates and the cones roll… Read more →

A roller stem is a specialized drill string component used in directional drilling and horizontal well drilling that consists of a section of drill string fitted with roller centralizers or bearing-supported rollers… Read more →

What Is a Roller-Cone Bit? A roller-cone bit is a rotary drilling bit that cuts rock through the combined crushing, chipping, and scraping action of two or three conical steel or tungsten-carbide-insert cutters that… Read more →

The rolling aging test is a standard laboratory procedure used in drilling fluid evaluation that subjects a mud sample to simulated downhole temperature and time conditions by sealing the mud in a metal roller cell,… Read more →

The rolling aging test is a standard laboratory procedure used in drilling fluid evaluation that subjects a mud sample to simulated downhole temperature and time conditions by sealing the mud in a metal roller cell,… Read more →

Root-mean-square velocity (Vrms) is a velocity parameter used in seismic data processing and analysis, calculated as the square root of the average of the squared velocity values weighted by the corresponding interval… Read more →

Rotary drilling is the dominant method for drilling oil and gas wells in which a drill bit is rotated at the bottom of the hole by torque transmitted from surface through a drillstring of connected steel pipe,… Read more →

A rotary steerable system (RSS) is a downhole drilling tool that enables continuous directional steering of the drill bit while the entire drill string rotates, as opposed to conventional slide drilling where rotation… Read more →

What Is a Rotary Table? A rotary table transmits rotation from the rig's prime mover to the kelly and bottom hole assembly by gripping the kelly through a drive bushing seated in the master bushing, converting the… Read more →

Rotational gas lift, more commonly written as rotative or closed rotative gas lift, is a form of gas lift in which the injected lift gas is captured at the production separator, recompressed, and re-injected into the… Read more →

A roughneck is a member of a drilling rig crew who works on the rig floor and in the derrick during drilling operations, performing the physically demanding manual labor involved in making and breaking drill pipe… Read more →

A round thread is the basic tapered threadform used across most oil country tubular goods (OCTG), defined by a rounded crest and root profile cut at eight threads per inch on a 1 in 16 taper (3/4 inch per foot on… Read more →

A round trip is the complete operation of pulling the entire drill string out of the wellbore (trip out or pull out of hole, POOH) and running it back to bottom (trip in or run in hole, RIH), which is required whenever… Read more →

A roustabout is an entry-level unskilled or semi-skilled laborer on an oil and gas drilling rig or production facility who performs general manual work under the direction of more experienced rig personnel — including… Read more →

Routine core analysis (RCAL) in petroleum reservoir engineering is the standardized set of basic physical measurements performed on core plugs or whole core samples retrieved from a wellbore to characterize the… Read more →

What Is a Royalty in Oil and Gas? A royalty in oil and gas is a non-cost-bearing interest that entitles the holder to receive a fraction of gross production or production revenue without contributing to drilling,… Read more →

A royalty interest in oil and gas law is a property right to receive a specified fraction of the gross production from a well or lease, free of the costs of exploration, drilling, and production, vesting in the holder… Read more →