- Industry: Oil & gas
- Number of terms: 8814
- Number of blossaries: 0
- Company Profile:
A metal or plastic vessel used to store or measure a liquid. The three types of tanks in an oil field are drilling, production and storage tanks.
Industry:Oil & gas
A metal filter assembly used to support and retain the sand placed during gravel pack operations. A range of sizes and screen configurations is available to suit the characteristics of the wellbore, production fluid and the formation sand.
Industry:Oil & gas
A mechanical or electronic device used to detonate perforating charges conveyed by tubing, drillpipe, coiled tubing or slickline. This term thus connotes any such device that is not initiated electrically from surface by wireline. A mechanical firing head consists of a percussion detonator that is struck by a firing pin. An electronic firing head is battery powered, to initiate an electric detonator. Electronic firing head systems are used with slickline, coiled tubing and TCP.
Industry:Oil & gas
A mechanical device that permits fluid to flow or pressure to act in one direction only. Check valves are used in a variety of oil and gas industry applications as control or safety devices. Check valve designs are tailored to specific fluid types and operating conditions. Some designs are less tolerant of debris, while others may obstruct the bore of the conduit or tubing in which the check valve is fitted.
Industry:Oil & gas
A mechanical device attached to tool strings or flush surface tubulars as they are assembled or disassembled. The safety clamp prevents the tool string from being dropped downhole accidentally if the slips or elevators securing the string lose their grip.
Industry:Oil & gas
A measuring device for determining the gas-flow rate. It is composed of a 1/8-inch tube inserted horizontally along the axis of the gas flowline. The pressure at the end of the tube is compared with the static pressure to determine the final gas flow rate within the flow line.
Industry:Oil & gas
A measurement of the vertical thickness of reservoir formation that is open to flow. The reservoir height is used in calculations and mathematical models to assess reservoir performance or potential productivity.
Industry:Oil & gas
A measurement that uses a source of gamma rays and a detector of gamma rays. The term is synonymous with density log, and is just an older name.
Industry:Oil & gas
A measurements-while-drilling log of formation resistivity. The log normally contains at least one attenuation and one phase-shift resistivity reading. In many cases there will be multiple curves of both, the difference being the depth of investigation. For the same nominal depth of investigation, the attenuation resistivity reads deeper than the phase-shift resistivity and is less affected by invasion, but more affected by surrounding beds and apparent dip. The attenuation measurement has a poorer vertical resolution and is less affected by anisotropy. Depths of investigation and vertical resolution of both measurements vary with the average formation resistivity. <br><br>Although depths of investigation are less than with wireline resistivity logs, the invasion at the time of measurement is usually small and it is possible to derive the resistivity of the undisturbed zone.
Industry:Oil & gas
A measurement of the nuclear magnetic resonance (NMR) properties of hydrogen in the formation. There are two phases to the measurement: polarization and acquisition. First, the hydrogen atoms are aligned in the direction of a static magnetic field (B0). This polarization takes a characteristic time T<sub>1</sub>. Second, the hydrogen atoms are tipped by a short burst from an oscillating magnetic field that is designed so that they precess in resonance in a plane perpendicular to B0. The frequency of oscillation is the Larmor frequency. The precession of the hydrogen atoms induces a signal in the antenna. The decay of this signal with time is caused by transverse relaxation and is measured by the CPMG pulse sequence. The decay is the sum of different decay times, called T<sub>2</sub>. The T<sub>2</sub> distribution is the basic output of a NMR measurement. <br><br>The NMR measurement made by both a laboratory instrument and a logging tool follow the same principles very closely. An important feature of the NMR measurement is the time needed to acquire it. In the laboratory, time presents no difficulty. In a log, there is a trade-off between the time needed for polarization and acquisition, logging speed and frequency of sampling. The longer the polarization and acquisition, the more complete the measurement. However, the longer times require either lower logging speed or less frequent samples.
Industry:Oil & gas
