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Discover the IHRDC Energy Glossarybeta

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T

TC

The abbreviation often used to represent time constant

TCF

Trillion cubic feet; a unit of measurement for natural gas volumes.

TCP/IP

Transmission Control Protocol/Internet Protocol. A common communication protocol used to configure networks on Ethernet and on the Internet.

TDA

TDA - time domain analysis

THD

Total Harmonic Distortion. A measure of the extent to which an electrical system's current draw is out of phase with the applied voltage.

Table

A type of chart used in the NEC to provide detailed information explaining code content

Tachometer

A feedback device in which a rotor shaft generates a voltage indicating its speed; commonly called a tach.

Tag

The name given to a device to identify it in a ladder diagram; synonym for alias, label, or symbol

Tag Number

The identification number assigned to a specific process instrument or field device, often tied to a process loop or plant location

Tag line

A tine, often made of fiber rope, that is used to help prevent a load from swaying or spinning during a lift and to help guide the load to its final position

Tagout

A procedure that uses tags on points of control to warn personnel, employees, and contractors not to operate equipment or activate switches and valves.

Tail gas

Leftover gas that leaves the catalytic reaction section of a sulfur recovery unit.

Take-off

The removal of either overhead product or bottoms product from a distillation system

Take-up

A value used to determine where to start a conduit bend

Tangent

A trigonometric function expressing the ratio between the lengths of the opposite and adjacent sides of a right triangle.

Tangential

Relating to a line or direction perpendicular to the radial direction.

Tank Battery

A system of two or more storage tanks located together at the same facility, connected by pipelines and used to store produced water, natural gas, and crude oil.

Tank Bottoms

The settlings in the bottom of a lease tank.

Tank Circuit

A tuned circuit in which current flow changes direction as a result of the charging and discharging of a capacitor and the expanding and collapsing of a magnetic field around a coil.

Tank Table

A table giving barrels of oil for any depth of oil in a lease tank.

Tank farm

A collection of storage tanks in one area of a facility.

Tankerman

An operator who is trained and certified to work on barges and handle marine vapor recovery equipment.

Tap

A connection at some point between the ends of a winding.

Taper gauge

A wedge-shaped gauge used to measure spaces between parallel surfaces. Also called a wedge gauge

Tar Sands

More technically called bituminous sands, a type of unconventional petroleum deposit.

Tare Weight

The empty weight of a vessel or the weight of a vessel with all air reĀ¬moved.

Target Octane

The desired octane number for a product.

Target Organ Hazards

Chemicals that target and create effects in specific body organs, including the liver, the kidneys, and the nervous system

Target Temperature Range

A temperature range including the temperature at which a fraction is separated.

Target organ effect

The characteristic of a hazardous substance that causes it to affect a specific organ.

Tau

Tau is the neutron decay time (in microseconds).

Techlog

Techlog is a Schlumberger owned Windows based software platform intended to aggregate all the wellbore information. It allows the user to interpret any log and core data.

Technical Data

Data collected from seismic surveys and the drilling of wells together with their technical interpretation.

Tectonic

Relating to the structure of the Earth's crust and the large-scale processes that control its properties and evolution over geological time.

Tectonic Event

A tectonic event is a physical occurrence resulting from the movement of the Earth's crust.

Tectonics

Tectonics is concerned with the processes which control the structure and properties of the Earth's crust, and its evolution through time.

Tectonics and Structure

Tectonics is concerned with the processes which control the structure and properties of the Earth's crust, and its evolution through time.

Telemetry

The highly automated communications process by which measurements are made and other data collected at remote or inaccessible points and transmitted to receiving equipment for monitoring and usage.

Telescoping gauge

A non-graduated precision measurement tool used to measure inside diameters and the distances between parallel surfaces. Also called a snap gauge

Temperature

The degree of hotness or coldness of a substance, as measured on a scale; the average molecular kinetic energy of a substance.

Temperature rise

The increase above ambient temperature of a transformer winding due to energizing and loading the transformer.

Temperature-compensated Flow Control Valve

A flow control valve that compensates for system temperature changes by changing orifice size

Tendinitis

An inflammation of a tendon that causes soreness, pain and restriction of movement. Tendinitis usually results from repetitious, forceful exertions, oftentimes when there is an awkward posture like a bent wrist or reaching overhead. It commonly occurs at the wrist, elbow and shoulder.

Tenosynovitis

Inflammation of the sheath within which a tendon slides back and forth. It usually occurs at the wrist and hand area and results in soreness, pain and a reduction of movement.

Tension Device

A tension device measures strain on the logging cable.

Tension Fracture

A tension fracture is the result of tensional stress in a rock.

Tension Load

The load (or force) on the piston rod as it travels toward the crank end of the cylinder.

Tension Loaded Disc

A pressure relief device that ruptures when pressure under the dome of the disc exceeds the disc design strength.

Tension Loading

The forces acting on a sucker rod during the upstroke because of the weight of the rods below it plus the weight of the fluid being lifted. Tension loading causes the rod to stretch along its vertical axis.

Tensor

A tensor method is a mathematical entity with components that change in a particular way in a transformation from one coordinate system to another. Tensor methods are used in "upscaling" reservoir parameters for use in reservoir simulation studies.

Terminal

A component that forms the end of an electrical circuit

Terminal Lugs

Certain types of larger terminals

Terminal Stud

The screw or bolt used to attach a terminal to a device

Terminal Temperature Difference (TTD)

The difference between a feedwater heater's feedwater outlet temperature and the saturation temperature of the steam in the condensing section

Terminating Resistor

A resistor used to close a communications link

Termination

A connection between a conductor and a piece of electrical equipment

Tertiary Recovery

Tertiary recovery, or enhanced oil recovery (EOR), is a process for extracting oil that has not already been retrieved through the primary or secondary oil recovery techniques.

Testing

The process by which the hazards that may confront entrants of a permit space are identified and evaluated. Testing includes specifying the tests that are to be performed in the permit space.

Tethyan Trend

The Tethyan Trend refers to an expansive area of fold belts that range from Western Europe to the Australian coast. Formation of this area began with the separation of Eurasia from Gondwana in post-Paleozoic times, resulting in the creation of the Tethys Ocean. Subsequent convergence and collision of the Africa and Eurasia tectonic plates, which began at the start of the Late Cretaceous, caused subsequent uplift and folding. Additional plate convergences of the Philippine, Pacific and Australia plates caused additional deformation in this area (De Graciansky et al., 2011).

Thalweg

Thalweg is the line of lowest elevation within a river valley or water course.

The Hydraulic Principle

The principle that pressure applied to a confined fluid is transmitted throughout the fluid and the confining vessel or system

Thermal Conductivity

A measurement of how easily heat is conducted through a substance; the ability of a substance to conduct heat.

Thermal Decay Time Log

A thermal decay time log is a record of the rate of capture of thermal neutrons in a formation after it is bombarded with a burst of neutrons.

Thermal Decay Time Logging Tools

Thermal Decay Time (TDT) tools are Schlumberger's early series of pulsed neutron capture logging tools.

Thermal Decomposition

Breaking down the chemical composition of glycol due to high temperature.

Thermal Energy

A form of energy related to the amount of heat in a fluid that can be stored or transferred.

Thermal Expansion

The expansion of a liquid that occurs when temperature increases.

Thermal Neutron Porosity

Thermal neutron porosity tools measure the slowing down and capture of neutrons between a source and one, or more, thermal neutron detectors.

Thermal Neutron Porosity Measurement

The thermal neutron porosity is a measurement of the slowing down and capture of neutrons between a source and one, or more, thermal neutron detectors. The neutron source emits high energy neutrons that are slowed mainly by elastic scattering to near thermal levels. Thermal neutrons have about the same energy as the surrounding matter, typically less than 0.4 eV. The slowing down process is dominated by hydrogen.

Thermal Neutrons

Free neutrons whose energies have a Maxwellā€“Boltzmann distribution with kT = 0.0253 eV (4.0 Ɨ 10ā»Ā²Ā¹ J) at room temperature.

Thermal Overload Device

A type of overload device that operates on the heat generated by current

Thermal degradation

A condition in which the temperatures used for distillation degrade, or decompose, the feed.

Thermal reaction section

The section of a sulfur recovery unit in which H2S is burned to produce SO2 and some sulfur is condensed and removed.

Thermistor

A temperature transducer that may be used as a temperature compensator in a measurement circuit

Thermocouple

A temperature measurement device consisting primarily of two wires of dissimilar metals that produce a small voltage proportional to temperature.

Thermocouple thermometer

A device that may be used to check the temperature of bearings in rotating equipment.

Thermometer

A device or instrument used to measure and indicate temperature.

Thermosiphon

A type of reboiler in which the process vapor and liquid are not separated before leaving the reboiler. Flow through the unit is created by a difference in densities

Thermosiphon Reboiler

A type of reboiler in which the process vapour and liquid are not separated before leaving the reboiler. Flow through the unit is created by a difference in densities

Thermostat

A pilot device that responds to temperature changes based on set point

Thief

A device that is pushed down into solid materials to obtain samples, or lowered into a lease tank to collect an oil sample for testing.

Thimble

A metal insert that is placed inside a loop of wire rope to prevent kinking and deformation of the loop

Thin Section, Petrographic Thin Section

A thin section, or petrographic thin section, is a laboratory preparation of a rock or mineral sample for use with a polarizing petrographic microscope, electron microscope and electron microprobe.

Thirty-two-bit Word

A digital expression of 32 bits; for example, 0100 0111 0100 0111 0100 0111 0100 0111.

Thorium

A chemical element with symbol Th and atomic number 90. A radioactive actinide metal, thorium is one of only four radioactive elements that still occur in quantity in nature as a primordial element. In sedimentary rocks, thorium is essentially resistate in character, as its major host minerals (monazite and zircon) are highly resistant to both chemical and physical breakdown. Because it is radioactive, thorium is identified in gamma ray logging tools, useful for correlating with offset wells during drilling.

Threading

A condition that Leaves fine tines on the surface of a commutator

Three-Phase

Separation into gas, oil and water.

Three-Phase Separation

Separating gas, oil, and water.

Three-phase Alternating Current

Three separate alternating currents that flow through three separate conductors

Three-phase Generator

A generator that has three sets of stator windings and produces three output voltages

Three-second rule

A defensive driving technique that keeps three seconds between vehicles and gives you enough time to react in the event of an unexpected event. When the vehicle in front of you passes a fixed object, you should be able to count to three seconds before your vehicle reaches the object.

Three-way Valve

A multiport valve with three ports

Threshold Limit Value (TLV)

The time-weighted average concentration for a normal eight-hour workday to which nearly all workers may be repeatedly exposed without adverse effect.

Throat Bushing

A bushing at the end of a pump's stuffing box that prevents packing from being pushed out of the stuffing box into the suction eye of the impeller

Throttling

The regulation of fluid flow by positioning a flow control valve somewhere between fully open and fully closed. In compressors, partially opening the suction valve to control the volume of gas entering the cylinder, though this increases discharge temperature and horsepower requirements and is used only as a temporary control measure.

Thrust Bearing

A bearing that prevents shaft movements in the same direction as the centerline of the shaft

Thyristor

The thyristor is a solid-state semiconductor device with four layers of alternating N and P-type material.

Tie wrap

A length of material, usually nylon, that has a self-locking device at one end

Tight Emulsion

An emulsion which is difficult to break.

Tight Formation

A tight formation is a relatively impermeable reservoir rock from which hydrocarbon production is difficult.

Tight Rocks, Tight

Tight rocks are those formations with lo permeability.

Tight gas

Natural gas produced from relatively impermeable rock. Getting tight gas out usually requires enhanced technology applications like hydraulic fracturing. The term is generally used for reservoirs other than shale.

Time Base

The interval in which a timer counts elapsed time

Time Base Accuracy

An indication of how accurately the horizontal system of an oscilloscope displays the timing of a signal; usually listed as a percentage error

Time Constant

The time between when a process variable begins to respond to a changed control output and when it has substantially re-stabilized. Also called lag.

Time domain analysis

Analysis of data and mathematical calculations in reference to time

Time-lapse Mode Logging

Time-lapse mode logging is the repeated acquisition with the same well logging tool at designated time intervals. Systematic time-lapse pulsed neutron capture logging gives a dynamic picture of the reservoir saturation response to production and water injection operations.

Timed Contacts

The contacts on a timer that become energized when the timer has timed out

Timer

A time-delay relay

Timing Relay

A relay that imposes a brief delay before sending signals that cause breakers to trip

Tip

The part of an oxy-fuel gas welding torch that supplies the oxygen and acetylene mixture to the flame. Also called a nozzle.

Tire concept

A defensive driving technique that involves being able to see the bottom of the tires of the vehicle in front of you when you stop.

Title Block

A block of information on a diagram that contains details such as the diagram's name, what system or unit it is for, an identification number, revision number, and other information.

Titration

A test that uses a chemical reaction to determine the concentration of a solution

Tongue

The part of a terminal that connects to the terminal stud

Tongue-and-groove ļ¬‚ange

A ļ¬‚ange with a raised area on one half that contains a groove into which the tongue from the opposite ļ¬‚ange half ļ¬ts.

Top Drive

A device that turns the drill string, consisting of one or more motors connected with appropriate gearing to a short section of pipe called a quill, which may be screwed into a saver sub or the drill string itself. The top drive is suspended from the hook, so the rotary mechanism is free to travel up and down the derrick.

Top Reflux

Straight run gasoline from the accumulator that is pumped back into the top of an atmospheric tower.

Topographic features

The physical features of an area

Topset, Topset Beds

Topset beds are the nearly level layers of sediment deposited on the top of a delta.

Torch

The component of an oxy-fuel gas welding rig that mixes the oxygen and acetylene to create a flame

Torch soldering

A joining process for copper, where the tube and ļ¬tting are properly heated, and solder (a solid wire) touched to the joint melts and is drawn in between the tube and the ļ¬tting, sealing the joint.

Tornado Chart

A tornado chart is a plot representing the effect of invasion on resistivity measurements that have different depths of investigation. The plot assumes a step-profile model of invasion and determines true resistivity, flushed zone resistivity and diameter of invasion from ratios of deep, medium and shallow resistivity measurements.

Torque

A force that produces, or tends to produce, rotation; the turning or twisting force applied to an object, such as a motor shaft.

Torque Switch

A device used in a motor operator to limit the torque that develops in the gear train, cutting off current to the motor when the turning force reaches a preset limit.

Torque Tube

A linkage mechanism that provides a high pressure seal and a twisting, or torquing, action used to convey motions that result from changes in level.

Torque Tube Displacer

A type of displacer mechanism that converts the slight vertical motion of a displacer, through a special mechanical linkage, into a rotational motion that can be used to move a suitable indicator or can be amplified into a proportional signal for a transmitter or controller.

Tortuosity

Tortuosity is a measure of the geometric complexity of a porous medium. Tortuosity is a ratio that characterizes the convoluted pathways of fluid diffusion and electrical conduction through porous media.

Tortuosity of a Rock Formation

The severity of curvature and size of pore necks in the pore network of a rock formation.

Total Condenser

A condenser that condenses all of the vapors from a distillation tower

Total Flow

The amount of fluid that has passed a designated point

Total Organic Carbon

Total organic carbon (TOC) is the amount of organic carbon in a geological formation.

Total Organic Carbon (TOC)

Total organic carbon (TOC) is the amount of organic carbon in a geological formation. TOC is significant to oil and gas exploration because in sedimentary rock, it is a direct indicator for the rock's potential as a source rock in a petroleum system.

Total Petroleum Initially-In-Place

The quantity of petroleum estimated to exist originally in the naturally occurring accumulations. It includes the estimated quantity of petroleum in known accumulations (before any production), together with the estimated quantities in yet to be discovered accumulations.

Total Recordable Rate (TRR)

The total recordable rate is a measure of the rate of recordable cases, normalized per 100 workers per year. The factor is derived by multiplying the number of recordable injuries in a calendar year by 200,000 (100 employees working 2,000 hours per year) and dividing this value by the total man hours actually worked in the year.

Total Residual Chlorine

The total amount of free chlorine that remains in a process stream after the stream has been treated with chlorine. Abbreviated as TRC

Total Shareholder Return (TSR)

Represents share price appreciation and dividends returned to shareholders over a period. It is calculated as follows: [(stock price at the end of the period) ā€“ (stock price at the start of the period) + (dividends paid during the calculation period) Ć· (stock price at the start of the period)].

Total current into VCC+

Maximum current that can be supplied to the positive power terminal of the op-amp. Usually specified as an absolute maximum.

Total harmonic distortion

The ratio of the RMS voltage of the first nine harmonics of the fundamental signal to the total RMS voltage at the output.

Total power dissipation

The total dc power supplied to the device less any power delivered from the device to a load.

Total pressure

The sum of the static pressure and the velocity pressure in a fan system.

Totalizer

Either a mechanical or electronic device which counts pulses.

Toxic chemicals

Chemicals that are poisonous

Toxicity

A reference to how poisonous, or toxic, a material is.

Trace

The visible shapes drawn on an oscilloscope screen by the movement of an electron beam

Trace Element

An element in a sample that has an average concentration of less than 100 parts per million measured in atomic count.

Tracer

A chemical, radioactive, or other material placed in the borehole fluid and later detected to infer information about the borehole or the drilled formations.

Tractor, Well Tractor.

A well tractor is an e-line, self-propelled robotic device used in highly deviated wells to drive tools down towards the toe of wellbores.

Tractor, Wireline Tractor

Tractors are electrical tools used to push the tool string into hole, overcoming wireline's disadvantage of being gravity dependent. These are used for in highly deviated and horizontal wells where gravity is insufficient, even with roller stem. They push against the side of the wellbore either through the use of wheels or through a wormlike motion.

Tractor, Wireline Tractor Conveyance

A tractor is a device for assisting a wireline logging tool to descend a deviated or irregular profile wellbore.

Training matchup

In order to create developments plans, SMEs align competency proficiency levels to identified training events that would close an employee competency gap in that area. Since the training matchup process links courses to specific levels of competency to close identified skill or knowledge gaps, it is important to consider the form of training selected, such as, e-Learning, instructor-led training, on-the-job training, etc. Other considerations include cost effectiveness, timeliness and whether the resource will deliver results that meet industry standards, statutory requirements and international acceptance (e.g., for accreditation or certification).

Transducer

A device that converts variations in a physical quantity (such as pressure, temperature, or brightness) into an electrical or mechanical signal, or vice versa. In gas measurement, any element or device that converts physical energy into mechanical or electrical energy.

Transducers

A device that converts pressure to an electrical impulse for transmitting to a recording device, e.g., mini-computer.

Transfer Pump

A pump that pressures the oil from the storage tank through the LACT unit.

Transfer Tripping

A method of providing high-speed protection for transmission lines by tripping the breakers in one substation and then sending a trip signal to the substation at the other end of a faulted line

Transformer

An electromagnetic device that transmits AC power from one circuit to another using electromagnetic induction, increasing or decreasing voltage to meet specific requirements.

Transgression, Marine Transgression

A marine transgression is a geologic event during which sea level rises relative to the land and the shoreline moves toward higher ground, resulting in flooding. Transgressions can be caused either by the land sinking or the ocean basins filling with water. Transgressions may be caused by tectonic events such as orogenies, severe climate change or isostatic adjustments following removal of ice or sediment load.

Transient Flow

Transient flow, is flow where the flow velocity and pressure are changing with time.

Transient Pressure Testing

Transient pressure testing records the pressure measurements as a function of time, in the wellbore at the productive interval, after the flow rate of the well is changed. They form the basis for well test analysis and are primarily used for determining the properties of the reservoir rock, skin effect and reservoir boundaries.

Transistor

A semiconductor device that transfers an electrical signal across a resistor.

Transit Time

The amount of time that it takes sound waves to travel from a transmitter to the surface of a liquid, reflect off the surface and return to a receiver.

Transition Zone

In reservoir engineering, the section of reservoir between the fully saturated hydrocarbon levels and the fully saturated water levels, where saturations grade from 100% water at the base to irreducible water saturation higher in the reservoir above the free water level. In seismic acquisition, an area between land and marine environments, typically comprised of marsh, lagoon, or shallow water zones.

Translational Slide

In translational slides, the mass displaces along a planar or undulating surface of rupture, sliding out over the original ground surface.

Transmission Line

Two conductors arranged in such a way as to have constant physical parameters such as characteristic impedance. The cable used for PLC network connections is a transmission line.

Transmission Path

The means by which the fluid in a system is transported from one place to another

Transmitter

In process control, a device containing a sensing element that measures a process variable (pressure, temperature, flow, etc.), translates it into an output signal, and sends the signal to a controller or DCS. In sonic level measurement, the device that converts electrical energy into sound waves.

Transmitter/Receiver

A device used to send and receive transfer trip signals

Transparent Tubing

A flexible, non-shrinkable tubing that is used basically as an insulating sleeve. Also called spaghetti tubing.

Transport Layer

The network protocol level that defines the data packets that transmitting and receiving devices pass back and forth, data flow control procedures, and error response routines

Transverse Dune

Transverse dunes are sand dunes formed across the direction of the winds that prevail in a given area.

Transverse Relaxation Time

The transverse relaxation time (T2) is an indication of how fast the tipped protons in the fluids relax transversely, relative to the axis of the static magnetic field during nuclear magnetic resonance logging.

Trap, Hydrocarbon Trap

A trap consists of a geometric arrangement of porous and permeable, reservoir and impermeable seal rocks which, when combined with the physical and chemical properties of subsurface fluids, can allow hydrocarbons to accumulate.

Travel Time, Sonic Travel Time, Transit Time

Travel time is the duration of the passage of a signal from the source through the Earth and back to the receiver.

Traveling Valve

The valve in a rod pump that is on the part of the pump that moves up and down with the pumping cycle.

Tray

A plate holding bubble caps and downcomers in a contactor column. There are usually 5 to 7 trays in each contactor column.

Tray dryer

A dryer that uses heat transfer and hollow shelves to dry material that is placed on trays.

Treating section

The section in a amine treatment unit in which amine contacts the sour fuel gas stream and H2S is absorbed by the amine.

Trend

A consistent pattern, such as a gradual increase or decrease, in the value of a process variable over a period of time. On a control chart, a pattern of instability clearly showing a gradual upward or downward direction.

Triac

A three-terminal silicon device that functions as two SCRs configured in an inverse, parallel arrangement, providing a means of providing load current during both halves of the AC supply voltage. A TRIAC is generally used for motor speed control.

Triangle

A closed shape that has three sides and three angles

Triaxial Compression Test

A triaxial compression test is when a cylindrical specimen of rock encased in an impervious membrane is subjected to a confining pressure and then loaded axially to failure.

Tribolectric

Nuisance electrostatic charging, or Triboelectric charging, has become more and more common in the modern world, due primarily to widespread use of synthetic fabrics and plastics. These materials are good insulators and do not dissipate charge once it has been separated. Examples of such charging, such as those below, can be used effectively in electrostatic demonstrations.

Trigger

In oscilloscopy, the circuit that initiates a horizontal sweep and determines the beginning point of the waveform. In digital electronics, a momentary change in input signals that causes the state of a flip-flop to change.

Trigger Hold-off Control

A control that inhibits an oscilloscope's trigger circuit from looking for a trigger level for some specified time after the end of a waveform

Trigger Level

The voltage level that a trigger source signal must reach before the trigger circuit initiates a sweep

Trim Components

Selected blend components whose amounts are increased or decreased during blending to maintain the target octane number and RVP.

Trimming

Increasing or decreasing the amounts of selected components in a blend to maintain the target octane number and RVP.

Trip

The immediate stop of an operating piece of equipment, such as a pump or turbine. In metering, the movement of a displacer from a starting point to a stopping point.

Triple

Three joints (sections) of drill pipe (each approximately 30 ft / 9.1 m) screwed together.

Tripping Drill Pipe, Tripping

The act of pulling the drill string or bottom hole assembly out of the hole, or replacing it in the hole. A round trip includes pulling out and returning to the bottom of the borehole.

Trolley

A component that is mounted onto the bridge of an overhead crane and used to carry the hoist mechanism back and forth across the bridge

Troubleshoot

To locate and identify the cause of a problem

Troubleshooting

A process of detecting problems, determining their causes, and correcting the problems.

True Power

Power used to do useful work

Truth Table

A tabular description of a logic function that lists all possible combinations of input variables together with the corresponding output variables for each state, used for Boolean functions such as AND, OR, NOT, IMPLIES, XOR, NAND, and NOR.

Tube Side

The area within the tubes and heads of a shell and tube heat exchanger

Tube axial fan

A type of axial fan that is basically a propeller fan built inside a housing, which helps collect and direct the air.

Tube-Side Fluid

The fluid flowing through the inside of the tubes in a shell and tube heat exchanger.

Tuberculocidal disinfectant

A hospital disinfectant used on inanimate surfaces and objects to destroy the bacteria that causes tuberculosis and other pathogenic microorganisms.

Tubing

Tubing, or production tubing, is a wellbore tubular used to produce reservoir fluids. Production tubing is assembled with other completion components to make up the production string.

Tubing Pump

A rotary positive displacement pump that moves liquid by squeezing it through flexible tubing

Tubulence

The flow of a fluid in an erratic, nonlinear motion caused by pipe fittings, valves, rough surfaces, etc.

Tune

To set the parameters of a control algorithm

Tuned Circuit

A circuit that uses components to determine the frequency of the signal produced by an oscillator.

Tunnel diode

A specially designed diode that can be highly conductive in both directions because it is heavily doped and has a very thin P-N junction. It has a unique characteristic of having a negative resistance in the forward-biased direction. The negative resistance region makes it highly effective as a high-speed switch.

Turbidite

Turbidites are sand deposits that flow from shallow regions into deeper water following meandering channels, which are progressively stacked as deposition continues.

Turbidite, Turbidity Flows

A turbidite is the geologic deposit of a turbidity current, which is a type of sediment gravity flow responsible for distributing vast amounts of clastic sediment.

Turbidites

Turbidites are sedimentary rocks formed by a turbidity current, a subaqueous sediment gravity flow that transports sediment into deep-marine environments. They are characterized by distinct layering and grading as larger particles settle out first, followed by finer ones.

Turbidity

A measure of the cloudiness or concentration of suspended particles in a liquid or solution.

Turbidity Meter

An instrument that measures the concentration of suspended particles in a solution

Turbine

A machine for generating rotary mechanical power from the energy of a stream of fluid (such as water, steam, or hot gas), converting kinetic energy to mechanical energy through the principles of impulse and reaction, or a mixture of the two. In power plants, it converts energy stored in steam, water, or combustion gases into the mechanical energy needed to turn a generator.

Turbine Control Valves

Specially designed, hydraulic cylinder operated valves that determine the amount of steam entering the turbine.

Turbine Trip

A sudden shutdown of a turbine by quickly closing all steam supply valves, shutting off all steam flow. May also trip the generator and boiler, and may occur in response to an emergency situation.

Turbulence

The flow of a fluid in an erratic, nonlinear motion caused by pipe fittings, valves, rough surfaces, etc.

Turn-off time (shutdown)

The time from when the turn-off voltage is applied to the shutdown pin to when the supply current has reached half of its final value.

Turn-off voltage (shutdown)

The voltage required on the shutdown pin to turn the device off.

Turn-on time (shutdown)

The time from when the turn-on voltage is applied to the shutdown pin to when the supply current has reached half of its final value.

Turnbuckle

A rigging component or device used to make small adjustments in the length or tension of a wire rope, chain, or sling leg.

Turning Gear

A motor and gear arrangement that keeps the turbine rotor turning at a constant speed to maintain uniform cooling of the rotor and thus prevent it from warping, bowing, or sagging during turbine shutdown or prior to startup.

Turns Ratio

The ratio of the number of turns of wire in the primary winding of a transformer to the number of turns in the secondary winding.

Twisted Pair

A type of cable in which pairs of conductors are twisted together to minimize interference pickup

Two-Phase

Separation into gas and liquid.

Two-Phase Separation

Separating natural gas from liquids.

Two-Phase Sample

A sample which contains both gas and liquid; creates inaccurate sample analysis.

Two-Phase Separation

Separating natural gas from liquids.

Two-cycle Engine

Engines that perform intake, compression, power and exhaust in two strokes of the piston, providing one revolution of the crankshaft.

Two-holing

A method of installing ļ¬‚anges so that the bolt holes of each ļ¬‚ange half line up.

Two-pass Condenser

A type of condenser that has a partition to divide one waterbox into inlet and outlet sections so that circulating water can make two passes through the condenser

Two-slot Addressing

An I/O addressing scheme where a pair of slots in the I/O rack is defined as a 16-bit group

Type Curve Analysis

Type curve analysis is a method for quantifying well and reservoir parameters such as permeability, skin damage, fracture half-length, dual porosity parameters, by comparing the pressure change and its derivative of the acquired data to reservoir model curve families, called type curves.

talus

Talus forms when rocks are weathered and erode from a cliff or steep slope. The resulting debris, which can include anything from small pebbles to large boulders, accumulates at the base of the cliff or slope.

terrigenous

Refers to materials, particularly sediments such as mud, clay, sand, gravel, volcanic materials, and boulders, that originate on land through weathering and erosion and are transported to marine or other depositional environments by rivers, wind, glaciers, or other processes.

terrigenous (clastic) sediment

Terrigenous sediments are sediments that come from land and are the most abundant type of sediment. They are created when rocks on land are eroded by wind, rivers, and volcanism, and are then transported by waterways.

terrigenous sediments

Terrigenous sediments are derived from eroded rocks on land (including mud, clay, sand, gravel, volcanic materials and boulders) and are transported by rivers to the sea where they are deposited on continental slopes, shores or shelves.

tests

In this context, a test is the term for a foraminifera's shell. Foraminifera are a group of single-celled organisms that build a shell-like structure called a test, which is typically made of calcium carbonate or other materials.

texture

In geology, texture refers to the size, shape and arrangement of the grains, crystals or particles within a rock or soil.

thief zones

A formation encountered during drilling into which circulating fluids can be lost.

tight

A relatively impermeable reservoir rock formation that does not allow fluids to pass through easily, making hydrocarbon production extremely difficult.

toe

Toe refers to the bottom or base of a slope, specifically the point where the slope meets a flat structure, or the outermost margin of displaced material during a landslide.

toeset and foreset dips

Foreset dips are characterized by a depositional angle ranging between 25Ā° and 30Ā°, but they can reach 40Ā° if the sediment is sufficiently coarse. Toeset dips represent the transition between the steeply inclined foreset and the sub-horizontal bottomset beds.

tops

ā€œTopsā€ or ā€œpicksā€ are the common name for the top surface of a geologic layer.

township

A survey township is a geographic reference used to define property locations for deeds and grants.

traces

A trace is the seismic data recorded for one channel. Typically, this is the sum of the recordings of the receivers in a group, or, with wireless receiver units, a single receiver group.

traction

Traction is a process that moves larger sediment grains or rocks along a riverbed, shore or planar surface by rolling or sliding them. This usually involves moderate to high water or wind velocity.

transgressing

Transgression occurs when the sea level rises and the shoreline moves backward across the land, causing flooding.

trim

Trim is an object's floating angle in the water, with respect to its fore and aft components.

turbidity currents

A turbidity current is a dense, sediment-laden flow of water that moves downslope in a body of water. The added sediment makes the water denser and heavier than the surrounding clear water. These currents transport vast amounts of sediment from shallow areas to deeper regions and can erode the seafloor.