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

A laboratory device used to indicate miscibility between reservoir oil and injection gas. A gas bubble is injected into an oil-filled visual cell at a given temperature and test pressure. The change in shape of the… Read more →

An aggregate of minerals or organic matter (in the case of coal, which is not composed of minerals because of its organic origin), or volcanic glass (obsidian, which forms a rock but is not considered a mineral because… Read more →

The study of the physical characteristics and behavior of rock. Rock mechanics can include analysis of and relationships between properties such as velocity, density, porosity, permeability, shear strength, and bending… Read more →

The physical characteristics of reservoir rocks that enable them to store fluids and to allow fluids to flow through them. The main properties of interest are rock porosities and permeabilities. Read more →

A set of characteristics that several rocks have in common. The characteristics of interest are usually those pertaining to fluid movement and fluid storage capacity. Read more →

Lightweight elevators designed for running and retrieving the sucker-rod string in wells equipped with a rod pump. Rod elevators can be used on a workoverrig or a rod unit specifically designed for running and… 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 lightweight workover unit specifically designed for running and retrieving rod strings and rod pumps. Rod units are generally truck-mounted and configured to suit the relatively light work associated with rod-pump… Read more →

To agitate a tanks contents with gas or air injected through a roll line. This procedure is performed to settle out impurities or obtain a more homogeneous mixture of the chemicals added to oil, such as when chemicals… Read more →

A thin, perforated pipe placed around the internal circumference of a tank. The purpose of the roll line is to agitate the contents of a tank. 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 downhole tool used on slickline operations conducted on a deviated wellbore to provide additional mass to the tool string. Incorporated in the assembly, rollers reduce the friction encountered as the roller stem is… Read more →

A tool designed to crush rock efficiently while incurring a minimal amount of wear on the cutting surfaces. Invented by Howard Hughes, the roller-cone bit has conical cutters or cones that have spiked teeth around them.… Read more →

A mud test in which the mud sample is mildly agitated by rolling (or tumbling) for the duration of the test, usually performed at a selected high temperature. Typically, the mud sample is sealed in a mud-aging cell and… Read more →

A mud test in which the mud sample is mildly agitated by rolling (or tumbling) for the duration of the test, usually performed at a selected high temperature. Typically, the mud sample is sealed in a mud-aging cell and… Read more →

The value of the square root of the sum of the squares of the velocity values divided by the number of values, symbolized by vrms. The root-mean-square velocity is that of a wave through subsurface layers of different… Read more →

A method of making hole that relies on continuous circular motion of the bit to break rock at the bottom of the hole. This method, made popular after the discovery of the East Texas Field by "Dad" Joiner in 1930, is… Read more →

A tool designed to drill directionally with continuous rotation from the surface, eliminating the need to slide a steerable motor.Rotary steerable systems typically are deployed when drilling directional, horizontal, or… 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 →

A gas-lift system that recycles the injected gas using compressors. This closed system does not require an external source of gas for operating the gas-lift system. Read more →

Generically, any member of the drilling crew. In conversational use, one might claim to have "roughnecked" in one's youth. This might actually refer to roughneck duties, or to one of the other crew positions, such as… Read more →

A basic threadform commonly found in oilfield applications. The thread profile of a round thread is designed to provide both mechanical strength and a hydraulic seal when made up to the correct torque. Read more →

What Is a Round Trip? A round trip (also called a pipe trip ) is the operation of pulling the entire drillstring out of the wellbore (POOH — pulling out of hole) and then running it back in (RIH — running in hole).… Read more →

Any unskilled manual laborer on the rigsite. A roustabout may be part of the drilling contractor's employee workforce, or may be on location temporarily for special operations. Roustabouts are commonly hired to ensure… Read more →

The set of measurements normally carried out on core plugs or whole core. These generally include porosity, grain density, horizontal permeability, fluid saturation and a lithologic description. Routine core analyses… 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 →

Ownership of a percentage of production or production revenues, produced from leased acreage. The owner of this share of production does not bear any of the cost of exploration, drilling, producing, operating, marketing… Read more →

Pertaining to a borehole wall that is rough. Read more →

A qualitative description of the roughness of a borehole wall. Alternatively, the term pertains to a borehole whose diameter changes rapidly with depth. The term usually refers to changes at the scale of logging… Read more →