Oil and Gas Terms Beginning with “P” — Page 8

What Is Pour Point? The pour point is the lowest temperature at which a petroleum fluid will flow under its own weight when cooled under standardised conditions (ASTM D97 or IP 15). Below the pour point, the fluid has… Read more →

In hydraulic pumping, the crude oil that is pressurized at surface to energize the bottom pump. Read more →

Volume of fluid injected in a well during hydraulic pumping. Read more →

A power-law fluid is a non-Newtonian fluid whose viscosity varies with the applied shear rate according to a power-law relationship: the apparent viscosity equals the consistency index (K) multiplied by the shear rate… Read more →

A pozzolan (from the Italian town of Pozzuoli near Naples, where volcanic ash with cementitious properties was quarried by the ancient Romans) is a siliceous or siliceous and aluminous material that, by itself,… Read more →

Pozzolanic describes a material that has little or no cementing value on its own but that reacts chemically with calcium hydroxide, in the presence of water and at ordinary temperatures, to form compounds with… Read more →

Abbreviation for concentration, parts-per-billion. For example, lead in a water sample is 10 ppb. Read more →

Abbreviation for density, pounds-per-gallon, more correctly written lbm/gal. For example, the density of water is 8.33 ppg at 60°F [16°C]. Read more →

Parts per million (ppm) is a dimensionless concentration unit expressing the ratio of the amount of a specific component to the total amount of the mixture, where the ratio is scaled by one million — meaning 1 ppm… Read more →

A precipitate is a solid that forms from solution when a reaction or change in conditions causes a dissolved substance to exceed its solubility limit and drop out of solution as particles. In petroleum engineering, the… Read more →

Precipitation in drilling fluid chemistry is the formation of an insoluble solid material from previously dissolved species in a fluid system — occurring through one of two principal mechanisms: (1) chemical reaction of… Read more →

What Is Precision? Precision quantifies the closeness of agreement between repeated results from the same measurement procedure applied to identical material under prescribed conditions, per ISO 5725. In well logging ,… Read more →

The right that a party has reserved or acquired to operate a lease, well, unit and/or concession. Read more →

The right that nonselling participating parties have in a lease, well or unit to proportionately acquire the interest that a participating party proposes to sell to a third party. Read more →

A preflush in petroleum engineering is a fluid stage pumped ahead of the primary treatment fluid (cement slurry, acid, fracturing fluid, or polymer) to prepare the wellbore or formation for the main treatment —… Read more →

A water-soluble starch that has undergone irreversible changes by heating in water or steam. Read more →

Prehydration in drilling and completion engineering refers to the process of thoroughly hydrating bentonite clay, polymer additives, or other water-swelling materials in fresh water before they are added to the full… Read more →

Prehydrated bentonite is sodium bentonite clay that has been mixed with fresh water and allowed to fully swell and hydrate before being added to a saline or inhibited water-based drilling fluid — a technique used when… Read more →

Prehydration is the practice of mixing certain drilling-mud additives into fresh water before they get added to the main mud system. The most common products treated this way are bentonite clay and XC (xanthan) polymer.… Read more →

Premium thread is the class of high-performance threaded connections commonly used in modern oil and gas well completions to provide superior sealing and mechanical performance compared to conventional API threaded… Read more →

The phase of a petroleum system after hydrocarbons accumulate in a trap and are subject to degradation, remigration, tectonism or other unfavorable or destructive processes. Read more →

A preserved core (also called a native-state core or preservation core) is a whole-core or sidewall core sample that has been cut from the subsurface formation and handled in a manner specifically designed to retain the… Read more →

The force distributed over a surface, usually measured in pounds force per square inch, or lbf/ in.2, or psi, in US oilfield units. Read more →

What Is a Pressure Buildup Test? A pressure buildup test (BU or PBU) is a pressure transient analysis method in which a producing well is shut in and the rate of pressure recovery in the wellbore is measured over time.… Read more →

What Is Pressure Buildup Analysis? Pressure buildup analysis (also called a buildup test or PBU test) is a well testing technique in which a producing well is shut in after a stabilized production period and the… Read more →

Pressure capability is the maximum differential pressure that an electrical submersible pump (ESP) can develop and maintain without failing or losing efficiency. It is the single most important sizing number when… Read more →

Pressure depletion is the progressive decline in reservoir pore pressure that occurs as fluids (oil, gas, and water) are produced from a reservoir, caused by the removal of reservoir fluid volume faster than it can be… Read more →

A decline in well pressure with time due to production. Read more →

The pressure decline after halting or reducing fluid injection in a well. Pressure falloff tests in injection wells are analogous to pressure buildup tests in production wells. Read more →

A pressure gauge in petroleum engineering is an instrument that measures fluid pressure at a specific location in the wellbore, surface facility, or pipeline system — either as a surface analog instrument (Bourdon tube,… Read more →