Petroleum, also known as crude oil, is a naturally occurring fossil fuel that is found beneath the earth's surface. It is formed from the remains of dead plants and animals that have been buried and subjected to high pressure and temperature over millions of years. Petroleum is a complex mixture of hydrocarbons, which are molecules made up of hydrogen and carbon atoms. It is a valuable resource that is used to produce a wide range of products, including gasoline, diesel fuel, jet fuel, lubricants, plastics, and chemicals.
The extraction and processing of petroleum involve drilling wells into underground reservoirs and pumping the crude oil to the surface. The crude oil is then transported to refineries, where it is processed into various products using techniques such as distillation, cracking, and reforming. The refining process involves separating the different hydrocarbons in the crude oil and converting them into more useful products.
Nomenclature & Symbols
Petroleum Engineering Index
- EPA Types of Crude Oil
- Oil & Gas Upstream, Midstream, and Downstream
- Oil & Gas Extraction
- Drilling Rig Design Classification
- Oil & Gas Facilities
- Drilling Rig Equipment
- Petroleum Equipment
- Petroleum Abbreviations
- Petroleum Engineering Glossary
- Class A: Light, Volatile Oils - These oils are highly fluid, often clear, spread rapidly on solid or water surfaces, have a strong odor, high evaporation rate, and is usually flammable. They penetrate porous surfaces such as dirt and sand, and may be persistent in such a matrix. They do not tend to adhere to surfaces. Flushing with water generally removes them. Class A oils may be highly toxic to humans, fish, and other organisms. Most refined products and many of the highest quality light crudes can be included in this class.
- Class B: Non-sticky Oils - These oils have a waxy or oily feel. Class B oils are less toxic and adhere more firmly to surfaces than Class A oils, although they can be removed from surfaces by vigorous flushing. As temperatures rise, their tendency to penetrate porous substrates increases and they can be persistent. Evaporation of volatiles may lead to a Class C or D residue. Medium to heavy paraffin-based oils fall into this class.
- Class C: Heavy, Sticky Oils - These oils are viscous, sticky or tarry, and brown or black. Flushing with water will not readily remove this material from surfaces, but the oil does not readily penetrate porous surfaces. The density of Class C oils may be near that of water and they often sink. Weathering or evaporation of volatiles may produce solid or tarry Class D oil. Toxicity is low, but wildlife can be smothered or drowned when contaminated. This class includes residual fuel oils and medium to heavy crudes.
- Class D: Nonfluid Oils - These oils are relatively non-toxic, do not penetrate porous substrates, and are usually black or dark brown in color. When heated, Class D oils may melt and coat surfaces making cleanup very difficult. Residual oils, heavy crude oils, some high paraffin oils, and some weathered oils fall into this class.
- Upstream - Anything having to do with the exploration and production of oil and natural gas.
- Midstream - Anything required to transport and store crude oil and natural gas before they are refined and processed into fuels and key elements.
- Field Processing
- Downstream - This includes everything involved in turning crude oil and natural gas into thousands of finished products.
- Well Site Selection
- Preparation of the Rig Sight
- Well Drilling
- Cementing and Testing
- Well Completion
- Hydraulic Fracturing
- Production and Fracking Fluid Recycling
- Well abandonment and Land Restoration
- Onshore - An onshore drilling operation can take place in two categories. One of the ways is mobile, which features a truck or trailer mounted rig. The other category is a conventional rig, which is stationary.
- Land Rig - These rigs are based on the drilling depths.
- Light Rig - depth 3,000 to 5,000 feet, 650 Hp
- Medium Rig - depth 4,000 to 10,000 feet, 1,300 Hp
- Heavy Rig - depth 12,000 to 16,000 feet, 2,000 Hp
- Ultraheavy Rig - depth 18,000 to 25,000 feet or more, 3,000 Hp or more
- Offshore - An offshore drilling rig has to create the same working conditions as for onshore rigs which can move from one point to another without any difficulty, and they have several additional features to adapt them to the marine environment, including a helaport, living quarters, cranes, and risers.
- Barge Rig - A drill barge is simple a barge equipped for oil and gas drilling, but compared to a drill ship it does not have its own propulsion system and must be towed to the drilling site by other vessels. The drill barge is used in inland, shallow or smooth offshore areas where the water depth is typically less than 20 feet.
- Jackup Rig - These rigs are well suited for shallow waters of 400 feet or less. As they are move into deeper waters, a mobile platform is needed. The rig can be self-elevated, with three or four movable legs that can be extended above or below the drilling deck, or hull. When the rig reaches the drill site, the crew jacks the legs downward through the water and into the sea floor. This anchors the rig and holds the drilling deck well above the waves.
- Platform Rig - These are normally located on the continental shelf in deep water up to 1,700 feet. They are made of steel or cement and intended to be permanent structures housing large facilities, heavy equipment, and big crews.
- Submersible Rig - They are barge that are designed to work in deeper water up to 50 feet deep. They have extensions that allow them to raise its upper hull above the water level.
- Semi-submersible Rig - These rigs are floating offshore drilling units with pontoons and columns that, when flooded with water, cause the unit to partially submerge to a predetermined depth. Most semi-submersibles are anchored to the sea bottom with mooring chains, but some use dynamic positioning, which allows the vessels to be held in position by computer-controlled propellers, known as thrusters.
- Drill Ship - They are much more like a traditional ship than jack-ups or semi-submersibles. They have a ship shape, run under their own power, and are able to operate in waters at 3,000 feet, while for greater depths dynamic positioning systems must be used, and with these the ship is capable of operating in 10,000 feet of water. Drill ships have a derrick mounted on deck with drilling equipment that passes through a moonpool in the bottom of the hull. The moonpool is a hole in the bottom of the hull that is covered during transit and uncovered for drilling, allowing drilling equipment to be mounted in the middle of the vessel and passed straight through the hull into the water.
- Oil & Natural Gas Well Site
- Oil Dehydration Facility
- Water Treatment Facility
- Waste Disposal
- Produced Water Injection Facility
- Oil Pipeline Breakout Facility / Truck Station
- Oil Refinery
- Oil Tank Farm / Storage Facility
- Pipeline Pumping Station / Oil & Natural Gas Refined Petroleum Pipeline Pump Station
- Refined Petroleum Product Terminal
- Natural Gas Gathering Compressor Station
- Natural Gas Plant - NGL Extraction and / or Fractionation
- Natural Gas Transmission Compressor Station
- Natural Gas Underground Storage Facility
- Bell Nipple
- Crown Block
- Drill Bit
- Drill Floor
- Drill Line
- Drill Pipe Stand
- Drill String
- Kelly Drive
- Kelly Hose
- Motor or power source
- Mud Pump
- Mud Pump Discharge Line
- Mud Pump Suction Line
- Mud Tank
- Racking Board (also called Monkey Board)
- Rotary Table
- Setback (Stand sets on Floor)
- Shale Shakers
- Stand (group of Drill Pipe)
- Swivel (Top Drive)
- Traveling Block
- Blowout Preventer
- Casing Head or Wellhead
- Casing Tool
- Cementing Unit
- Coil Tubing Unit
- Drilling Mud Pump
- Drilling Rig
- Fishing Tool
- Flow Line
- Frac Tank
- Fracture Pump
- Fracturing Unit
- Kelly Spinner
- Logging System
- Pipe Fitting
- Pipe Flange
- Pump Jack
- Pumping Unit
- Shale Shaker
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- Abandoned Pipeline - A transmission pipeline that has been permanently removed from service and left in place.
- Abandoned Well - A well permanently plugged in the drilling phase for technical reasons.
- Acid Gas - Hydrogen sulfide and carbon dioxide contained in natural gas and refinery streams; so named because they can cause corrosion
- Amine - Chemical used as a solvent to remove hydrogen sulfide and carbon dioxide from hydrocarbon streams
- API Gravity - The standard by which all crude oils are measured. API gravity is used to determine the specific gravity of crude oil and thus its density. Lighter crudes are more valuable because they are more easily refined into gasoline. Crude with an API gravity of 10 is equivalent in density to water.
- Appraisal Well - A well drilled as part of an appraisal drilling program which is carried out to determine the physical extent, reserves and likely production rate of a field.
- Area Classification Drawing - A hazardous area classification drawing (also known as an area classification drawing) outlines the classifications of areas where flammable liquids, gasses or vapors are handed, processed or stored.
- Associated Gas - A well drilled as part of an appraisal drilling program which is carried out to determine the physical extent, reserves and likely production rate of a field.
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- Bacdkfill - The filling in of a void in a utility ditch that was created by excavation, usually by replacing the soils that were removed.
- Barlow's Formula - The point just before or at when a pipe or tubing fails under pressure.
- Base Gas - Gas in a storage reservoir which provides the pressure necessary for designed withdrawals of working gas.
- Batch - A shipment of one type of product through a pipeline.
Batching Sequence - The order in which specific volumes of petroleum product are sent through a pipeline.
Battery Site - A gas or oil facility with product separation and multiphase delivery point measurement for one or more wells.
Benchmark Crude - A reference crude oil with whom the prices of other crudes are compared with.
- Biodiesel - An alternative renewable and biodegradable fuel, obtained from the chemical reaction of animal or vegetable oils mixed with alcohol and a catalyst (reaction known as transesterification). This fuel can also be obtained by the cracking and esterification processes.
- Biofuel - Any fuel derived by a variety of processes from an organic source that is renewable, capable of being replenished naturally.
- Bleed Ring - A ring section with one or more radial pipe connections designed to fit between standard flanges within the bolt circle, using conventional gasket material.
Blending - One of the final operations in refining, in which two or more different components are mixed together to obtain the desired range of properties in the final product.
Blending Plant - A facility which has no refining capability but is either capable of producing finished motor gasoline through mechanical blending or blends oxygenates with motor gasoline.
- Block Flow Diagram - A block schematic diagram is a simplified representation of a Process Flow Diagram (PFD).
- Blowdown - Condensate and gas is produced simultaneously from the outset of production.
- Blowout - When well pressure exceeds the ability of the wellhead valves to control it.
- Blowout Prevention - Casinghead equipment that prevents the uncontrolled flow of oil, gas and mud from the well by closing around the drillpipe or sealing the hole.
- Boiler Rating - The total heat transferred by the heating surfaces in Btu per hour.
- Bore - Trenchless stream crossing method by which a hole is drilled horizontally from bell hole to bell hole (with or without casing) to allow the installation of a pipeline.
- Borehole - The hole made by drilling or boring a well.
- Borrow Pit - An area where clay, gravel, rock, sand or soil has been removed/excavated and used for the construction of oil and gas infrastructure.
- Bottom Sediment Water - Water, being heavier than oil, will collect in the bottom of tanks if water is being produced with the oil. This water will contain some sediment material produced out of the well.
- Bottoms - Residue remaining in a distillation unit after the highest boiling point material to be distilled has been removed.
Brackish Water - Indefinite term meaning water with small amounts of salt. Saltier than fresh water.
Bridge Plug - A downhole tool (composed primarily of slips, a plug mandrel, and a rubber sealing element) that is run and set in casing to isolate a lower casing interval while testing an upper section.
- Brine Well - A well used for injecting fresh water into geologic formation comprised mainly of salt. The injected freshwater dissolves the salt and is pumped back to the surface as a saturated sodium chloride brine solution used as a feedstock in petrochemical refineries and in oil and gas well drilling and workover operations.
- Bulk Station - A facility used primarily for the storage and/or marketing of petroleum products which has a total bulk storage capacity of less than 50,000 barrels and receives its petroleum products by tank car or truck.
- Bulk Terminal - A facility used primarily for the storage and/or marketing of petroleum products which has a total bulk storage capacity of 50,000 barrels or more and/or receives petroleum products by tanker, barge or pipeline.
- Byproduct - Substances that are coincidentally created, without a separate commercial intent, in the course of producing another substance. Usually of lesser volume or value than primary or co-products.
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- Carbon Black - Finely divided particles of carbon in powder form used in the manufacture of tires and other rubber articles, plastics, inks and many other applications. Made by the incomplete combustion of oil, acetylene or natural gas.
- Casing - A hollow steel pipe cemented into position that is used to line a wellbore.
Casinghead Gas - Gas found naturally in oil and produced with the oil.
- Catalyst - A substance that accelerates or delays a chemical reaction, but does not undergo any permanent chemical change in this process.
- Cathodic Protection - A method used to control corrosion on the surface of a metal which can be above or below ground pipes, tanks, vessels, etc. This process is accomplished by placing a sacrificial anode (material) connected to the protected metal.
- Christmas Tree - The assembly of fittings and valves on the top of the casing which control the production rate of oil.
- Co-generation - The simultaneous generation of electricity and thermal energy (heat/steam process), through the sequential and efficient use of energy volumes from the same source. This increases the thermal efficiency of the thermodynamic system as a whole.
- Coal - A readily combustible black or brownish-black rock whose composition, including inherent moisture, consists of more than 50 percent by weight and more than 70 percent by volume of carbonaceous material. It is formed from plant remains that have been compacted, hardened, chemically altered, and metamorphosed by heat and pressure over geologic time.
- Coke - Solid carbon fuel derived from oil refinery cracking processes such as delayed coking.
- Commercial Field - An oil and/or gas field judged to be capable of producing enough net income, at sufficiently low risk, to make it economic for development.
- Compressor - A device that forces air or gas into a smaller area increasing the volume and creating a usable force of energy.
- Compressed Natural Gas - Methane stored at a high pressure that can be used in place of gasoline, diesel fuel, and propane.
- Corrosion - The thinning of a pipe wall that is typically caused by a chemical reaction from a corroding fluid or agent and is limited almost exclusively to metal products.
- Corrosion Allowance - The amount of material in a pipe or vessel that is available for corrosion without affecting the pressure containing integrity.
- Crack Spread - The difference in value between crude oil and the product or products refined from it, a reflection of Refining Margin.
- Crude Oil - A mixture of hydrocarbons that exists in liquid phase in natural underground reservoirs and remains liquid at atmospheric pressure after passing through surface separating facilities.
- Cushion Gas - The amount of gas required in a storage pool to maintain sufficient pressure to keep the working gas recoverable.
- Daisy Chain - The process by which a cargo of oil or oil products is sold many times before being delivered to the customer.
- Derrick - Steel structure mounted over the bore hole to support the drill pipe and other equipment which is lowered and raised during drilling operations.
- Developer - An individual or group of individuals who imply for permits to alter, construct and install buildings or improvements or change the grade on a specific piece of property.
- Direct Heater - Is designed such that the transfer of heat is accomplished by direct contact of the fluid with the firebox/ fire-tube.
- Direct Gas-fired Heater - The burner fires directly in the air stream being heated, rather than through a heat exchanger.
- Discovery Well - An exploratory well that encounters a previously untapped oil or gas deposit.
Dissolved Gas - Commonly referred to as solution gas.
- Distillate - Generic name for kerosene, diesel fuel and heating oil.
- Distillation - A common manufacturing process for separation/purification in which a liquid is converted to a vapor and the vapor is then condensed to a liquid.
- Distillation Pipeline - A natural gas pipeline other than a gathering or transmission line. A distribution pipeline is generally used to supply natural gas to the consumer and is found in a network of piping located downstream of a natural gas transmission line.
- Domestic Crude Oil - Crude oil produced in the United States including the outer continental shelf.
- Downhole - A term used to describe tools, equipment, and instruments used in the wellbore, or conditions or techniques applying to the wellbore.
- Downstream - A sector of the petroleum industry that refers to the refining of crude oil, and the products derived from crude oil
- Drill Mud - Drilling fluid used to clean and lubricate the drilling process, recover samples of the sub-surface formations to surface and to counteract the natural pressure of the formation.
- Drill Pipe Protector - A rubber or ball bearing steel ring attached to each joint of drill pipe to reduce the friction and subsequent wear between the drill pipe and casing.
- Drill String - Steel pipes roughly 10m long joined together to form a pipe from the drill bit to the drilling platform. It is rotated during drilling and is also the conduit for the drilling mud.
- Dry Gas - Almost pure methane gas, lacking water and with few heavy components.
- Dry Hole - A well which has proved to be non-productive.
- Dry Sand - Nonproductive sand encountered in drilling.
- Equipment Location Plan - A Plot General Arrangement Drawing or Equipment Location Plan is a drawing created to show the location of equipment relative to other pieces of equipment.
- Enhanced Oil Recovery - Various methods used to enhance production from an oil reservoir.
- Equipment Index - After the major process design has been completed, an equipment index (also known as an equipment list or equipment schedule) is created.
- Ethanol - Flammable liquid, also known as ethyl alcohol or grain alcohol, derived from plants and often added to gasoline as an oxygenate to boost octane, enhance combustion and reduce carbon monoxide emissions.
- Ethylene - A two carbon building block in the petrochemical industry, used to produce a variety of finished products, including plastics, fibers and resins.
- Expansion Joint - Heat and cold causes piping systems to expand and contract. This expansion and contraction can put enormous stresses on the pipe causing it to buckle or fail.
- Exploration Well - Drilling carried out to determine whether hydrocarbons are present in a particular area or structure. Sometimes known as a ‘wildcat well’, particularly in areas where little drilling has taken place previously.
- Facility - A buried or underground conductor, pipe, or structure used to provide utility services, such as electricity, natural gas, liquids refined from oil, oil, sewage, storm drains, telecommunications, or water.
- Facility Operator - Any person, utility, municipality, authority, political subdivision or other person or entity who operates or controls the operation of an underground line or facility.
- Flash Tank - A vessel used to separate the gas created from liquid when it is flashed from a high pressure to a low pressure.
- Fluid Coking - A thermal cracking process utilizing the fluidized-solids technique to remove carbon (coke) for continuous conversion of heavy, low-grade oils into lighter products.
- Foaming - A method of extinguishing oil fires by spraying with a foaming liquid.
Formation - A separate layer of rock or group of intermingled beds.
Frac - High pressure or explosive method of fracturing rock formations.
- Gasohol - A blend of finished motor gasoline containing alcohol (generally ethanol but sometimes methanol) at a concentration between 5.7 percent and 10 percent by volume.
- Gasoline - A lightweight material that flows easily, spreads quickly, and may evaporate completely in a few hours under temperate conditions. It poses a risk of fire and explosion because of its high volatility and flammability, and is more toxic than crude oil. Gasoline is amenable to biodegradation, but the use of dispersants is not appropriate unless the vapors pose a significant human health or safety hazard.
- Gas - Natural gas, flammable gas, or gas which is toxic or corrosive. Gasses are normally compared to air in terms of density.
- Gas Field - A field containing natural gas but no oil.
- Gas Injection - The process whereby separated associated gas is pumped back into a reservoir for conservation purposes or to maintain the reservoir pressure.
- Gas Lift - A system of pumping petroleum by gas instead of air.
- Gas Oil - A liquid petroleum distillate having a viscosity intermediate between that of kerosene and lubricating oil. It derives its name from having originally been used in the manufacture of illuminating gas. It is now used to produce distillate fuel oils and gasoline.
- Gas Transmission Line - A pipeline or other than a gathering line, that transports gas from a gathering line or storage facility to a distribution center, storage facility, or large volume customer that is downstream from a distribution center.
Gathering Line - A pipeline that transports oil or gas from a central point of production to a transmission line or mainline.
- Guy Anchor - The support to which derrick guys are attached.
- Guy Ring - Rings on the head block of a derrick mast to which the guy ropes are attached.
- Hazardous Liquid - Includes petroleum, petroleum products, anhydrous ammonia, and carbon dioxide.
- Hazardous Liquid Pipeline - All parts of a pipeline facility through which a hazardous liquids move in transportation, including, but not limited to, line pipe, valves, and other appurtenances connected to line pipe, pumping units, fabricated assemblies associated with pumping units, metering and delivery stations and fabricated assemblies therein, and breakout tanks.
- Heat Exchanger - A device used to transer heat from one medium to another at different temperatures. The heat transfer can be air or a liquid such as water or oil.
- Heater Treater - A pressure vessel that uses heat and residence time to separate clean, dry oil from incoming fluids. It usually is located immediately downstream of the Free Water Knockout during the oil dehydration process.
Heavy Crude - Crude oil of 20° API gravity or less; often very thick and viscous.
- Heavy Gas Oil - Petroleum distillates with an approximate boiling range from 651 degrees Fahrenheit to 1000 degrees Fahrenheit.
Heavy Oil - Lower gravity, often higher viscosity oils. Normally less than 28° API gravity.
- High Consequence Area - A location that is specifically defined in pipeline safety regulations as an area where pipeline releases could have greater consequences to the health and safety or the environment.
High-sulfur Distillate Fuel Oil - Distillate fuel oil having sulfur content greater than 500 ppm.
- Horizontal Directional Drilling - Also known as directional boring, this is a method of installing pipelines underground, where a whole is bored through a surface launched drilling rig.
Hub - A location where several pipelines interconnect.
- Hydrocarbon - Chemical compound containing hydrogen and carbon used as a fuel, e.g., petroleum, methane, butane.
Independent Producer - An energy company, usually in the exploration and production segment of the industry and generally, with no marketing, transportation or refining operations. A non-integrated producing company in the oil industry.
- Indirect Heater - Is where the heating element heats the water or another heating medium and the heating medium is then used to transfer heat to the process stream.
- Inhibitor - An additive that retards or stops an undesired chemical reaction such as spontaneous polymerization.
- Injection Well - A well used for pumping water or gas into the reservoir.
- Intelligent Well - A well equipped with monitoring equipment and completion components that can be adjusted to optimize production, either automatically or with some operator intervention.
- Intermediate Casing - A casing string set in place after the surface casing and before the production casing. The intermediate casing string provides protection against caving of weak or abnormally pressured formations and enables the use of drilling fluids of different density necessary for the control of lower formations.
Isobutylene - An olefinic hydrocarbon recovered from refinery processes or petrochemical processes.
Isohexane - A saturated branch-chain hydrocarbon. It is a colorless liquid that boils at a temperature of 156.2 degrees Fahrenheit.
Isoprene Feedstock - A byproduct of ethylene production, isoprene feedstock is used to make isoprene, which in turn is used to produce polyisoprene rubber for tires.
- Jack - Mechanism installed at the mouth of a petroleum well for transmitting mechanical power from a central pumping station.
- Jack Lines - Lines used to transmit motion from a pumping power to well pumping jacks.
- Jack Posts - Posts which support the band wheel shaft in a derrick.
- Jerk Line - A short cable connected to the crank pin and to a spudding pole to enable drilling tools to be operated without the use of the walking beam.
- Kelly Drive - A type of well drilling device using a section of pipe with a (three-, four-, six-, or eight-sided) or splined outer surface, which passes through the matching bushing and rotary table.
- Kerosene - A lightweight material that flows easily, spreads rapidly, and evaporates quickly. Kerosene is easily dispersed, but is also relatively persistent in the environment.
- Kill - The act of stopping a well from flowing.
- Kinetic Energy - The energy an object possesses by virtue of its motion. If it moves, it has kinetic energy.
- Knockout - A separator used to remove excess gas or water from the produced fluid stream.
- Knockout Drum - A vessel wherein suspended liq- uid is separated from gas or vapor.
- Lease - Legal document giving an operator the right to drill for or produce oil or gas; also, the land on which a lease has been obtained.
- Lifting Costs - The operating costs of producing oil or gas from a well, licence or lease.
Light Gas Oil - Liquid petroleum distillates heavier than naphtha, with an approximate boiling range from 401 degrees to 650 degrees Fahrenheit.
- Line Pipe - The length of a pipe comprising the main part of transmission pipeline segments. Line pipe is identified as only the pipe, excluding ancillary facilities and structures that are located on company property adjacent to the pipeline right-of-way.
- Lined Pit - Dugouts excavated next to drilling rigs that are lined with impermeable geosynthetic materials to safely store drilling fluids from natural gas or oil fields. In order to protect waterfowl and other wildlife from coming into contact with this water, wire fencing is often used to cover the pit and brightly coloured flagging on the fence perimeter acts as a deterrent.
- Liquefied Natural Gas - Natural gas that has been converted to a liquid form for ease and safety of non-pressurized storage or transport.
- Liquid Petroleum Gas - A group of hydrocarbon gases, primarily propane, normal butane, and isobutene, which is derived from crude oil refined or natural gas processing.
- Lubricating Oil - A medium-weight material that flows easily and is easily dispersed if treated promptly. This oil has a low volatility and moderate flash point, but is fairly persistent in the environment.
- Making Hole - The depth gained in drilling wells.
- Mass Flow Rate - The average velocity of a mass that passes by a point.
- Melting Point - A solid is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends (usually slightly) on pressure and is usually specified at standard pressure.
- Methane - The principal constituent of natural gas. The simplest hydrocarbon molecule, containing one carbon atom and four hydrogen atoms.
Methanol - A light, volatile alcohol intended for gasoline blending as described in Oxygenate definition.
- Midstream - The processing, storage and transportation, primarily pipelines, sector of the petroleum industry.
- Mud - A mixture of base substance and additives used to lubricate the drill bit and to counteract the natural pressure of the formation.
- Natural Gas Liquids - These gases belong to the same family of hydrocarbons as natural gas and crude oil, but are typically ethane, butane and isobutane.
Natural Gas Processing Plant - Facilities designed to recover natural gas liquids from a stream of natural gas that may or may not have passed through lease separators and/or field separation facilities. These facilities control the quality of the natural gas to be marketed. Cycling plants are classified as gas processing plants.
- No. 2 Fuel Oil - A lightweight material that flows easily, spreads quickly, and is easily dispersed. This fuel oil is neither volatile nor likely to form emulsions, and is relatively non-persistent in the environment.
- No. 4 Fuel Oil - A medium-weight material that flows easily, and is easily dispersed if treated promptly. This fuel oil has a low volatility and moderate flash point, and is fairly persistent in the environment.
- No. 5 Fuel Oil (Bunker B) - A medium-weight to heavyweight material with a low volatility and moderate flash point. Preheating may be necessary in cold climates, and this fuel oil is difficult, if not impossible, to disperse.
- No. 6 Fuel Oil (Bunker C) - A heavyweight material that is difficult to pump and requires preheating for use. This fuel oil may be heavier than water, is not likely to dissolve, is difficult or impossible to disperse, and is likely to form tar balls, lumps, and emulsions. It has a low volatility and moderate flash point.
- Nozzle - An opening in a tank or vessel for a flanged connection. To strengthen nozzles a reinforcing pad is used.
- Octane Rating - A number used to indicate gasoline's antiknock performance in motor vehicle engines.
- Offset Well - Well location adjoining another well site.
- Oil Pool - A term applied to a productive oil field, an accumulation of liquid hydrocarbons in sedimentary rock that yields petroleum on drilling.
- Oil String - The string of casing or tubing which is let down to the oil sand and through which the oil flows to the surface.
Operator - A person, acting for himself or as an agent for others and designated to the Commission as the one who has the primary responsibility for complying with its rules and regulations in any and all acts subject to the jurisdiction of the Commission.
- Orifice Plate - Measures the flow of a liquid or gas by the difference in pressure from the upstream to the downstream.
- Orphan Well - A well or associated site that does not have a legally responsible and/or financially viable party to deal with its decommissioning and reclamation.
Overproduction - Production in excess of the well's monthly allowable.
Oxidation - Oxidation is the addition of oxygen, removal of hydrogen, or the removal of electrons from an element or compound. In the environment, organic matter is oxidized to more stable substances.
- Ozone - Ground-level ozone is a colourless gas that forms just above the earth’s surface.
- Packing Assembly - The arrangement of the downhole tools used in running and setting a packer.
- Packing Elements - The set of dense rubber, washer-shaped pieces encircling a packer, which are designed to expand against casing or formation face to seal off the annulus.
- Parallel Strings - A multiple completion, the arrangement of a separate tubing string for each zone produced, with all zones isolated by packers.
- pH - Is how basic or acidic something is. pH range is from 0 to 14, where 0 is most acidic, 14 most basic, and 7 is neutral.
- Perforated Pipe - Sections of pipe (such as casing, liner, and tail pipe) in which holes or slots have been cut before it is set.
- Perforating Gun - A device fitted with shaped charges or bullets that is lowered to the desired depth in a well and fired to create penetrating holes in casing, cement, and formation.
- Perforation - A hole made in the casing, cement, and formation through which formation fluids enter a wellbore. Usually several perforations are made at a time.
- Permeability - The quality of the soil to enable water to move downward through the soil.
Petroleum Coke - A residue high in carbon content and low in hydrogen that is the final product of thermal decomposition in the condensation process in cracking. This product is reported as marketable coke or catalyst coke. Coke from petroleum has a heating value of 6.024 million Btu per barrel.
- Petroleum Jelly - A semi-solid oily product produced from de-waxing lubricating oil basestocks.
- Petroleum Products - Flammable, toxic, or corrosive products obtained from distilling and processing of crude oil, unfinished oils, natural gas liquids, blend stocks and other miscellaneous hydrocarbon compounds.
- Pig - Devices that are inserted into and travel throughout the length of a pipeline driven by a product flow. They were originally developed to remove deposits which could obstruct or retard flow through a pipeline.
- Pipeline - Pipelines include all parts of those physical facilities through which gas, hazordous liquids, or carbon dioxide moves in transportation.
- Pipeline Pigging - A pig is a Pipeline Inspection Gauge. Pig's scrape the inside of the pipeline and perform various maintenance jobs like cleaning, clearing, maintenance, inspection, dimensioning, process and pipeline testing operations on new and existing pipelines.
- Pipe - A hollow tube that can carry products such as fluid, gas, granular and more. Pipe is identified by nominal pipe size and the wall thickness identified by schedule number.
- Pipe Dog - A hand tool that is used to rotate a pipe whose end is accessible, consisting of a small, short steel bar the end of which is bent at a right angle to the handle, and then quickly returned, leaving only enough space between the jaws to slip over the wall of pipe.
- Pipe Fitting - A piping component that is used to join piping, change the direction or diameter of piping or end the pipe. They are a versatile piping component which are necessary in modern piping system.
- Pipe Flange - A bolted connection where two pieces of pipe, equipment, fittings or valves are connected together to form a piping system. Flanges provide access for when equipment (or piping) needs to be cleaned, inspected or reconfigured.
- Pipe Rack - Used to support piping, instrumentation, cable tray and other components in a process facility.
- Pipe Tongs - Tool for screwing or unscrewing pipe joints. A band tool for gripping or rotating pipe.
Plug - Seal off formations to stop open communication of formation fluids within a well.
- Pool - A natural underground reservoir containing an accumulation of petroleum.
- Porosity - The ratio between the pore volume of a substance and its total volume. Porosity of a measure of a rocks capacity to store fluids.
- Pressure - It is the force exerted perpendicular to the surface of an object and is expressed as force per unit area.
- Pressure Loss - The difference in upstream and downstream pressure.
- Pressure Vessel - They can used for storage of high pressure gas, gas scrubbers, two and three phase separators and other functions. They can have various internals depending on the process.
- Process Flow Diagram - Shows the relationships between the major components of a system or process plant.
Processing Gain - The volumetric amount by which total output is greater than input for a given period of time. This difference is due to the processing of crude oil into products which, in total, have a lower specific gravity than the crude oil processed.
- Processing Loss - The volumetric amount by which total refinery output is less than input for a given period of time. This difference is due to the processing of crude oil into products which, in total, have a higher specific gravity than the crude oil processed.
- Propane - A normally gaseous straight-chain hydrocarbon. It is a colorless paraffinic gas that boils at a temperature of –43.67 degrees Fahrenheit. It is extracted from natural gas or refinery gas streams.
- Proven Field - An oil and/or gas field whose physical extent and estimated reserves have been effectively determined.
Reactor - The vessel in which chemical reactions takes place.
- Reclamation - The process of restoring the surface area of a well site, access road and related facilities to original conditions.
- Reduced Crude - The product obtained after removal, by atmospheric distillation, of the light components of crude oil.
- Refining - The process of separating crude oil into useful components including gasoline, diesel fuel, jet fuel, fuel oil, and other products.
Refinery Margins - The difference in value between the products produced by a refinery and the value of the crude oil used to produce them. Refining margins will thus vary from refinery to refinery and depend on the price and characteristics of the crude used.
- Refinery Production - Petroleum products produced at a refinery or blending plant.
- Refinery Yield - Represents the percentage of finished product produced from input of crude oil, hydrogen, and other hydrocarbons and the net input of unfinished oils.
Regasification - The process by which LNG is heated, converting it into its gaseous state.
- Reseller - A firm (other than a refiner) that is engaged in a trade or business that buys refined petroleum products and then sells them to a purchaser who is not the ultimate consumer of those refined products.
Residue - The bottoms from a crude oil distilling unit, vacuum flasher, thermal cracker or visbreaker.
Residue Gas - Gas remaining after processing and extraction of NGL.
Residual Fuel Oil - A general classification for the heavier oils, known as No. 5 and No. 6 fuel oils, that remain after the distillate fuel oils and lighter hydrocarbons are distilled away in refinery operations.
- Reservoir - A porous and permeable underground formation containing a natural accumulation of producible oil and/or gas that is confined by impermeable rock or water barriers and is individual and separate from other reservoirs.
- Reynolds Number - Measures the ratio of inertial forces (forces that remain at rest or in uniform motion) to viscosity forces (the resistance to flow).
- Roustabout - Any unskilled manual labourer on the oil rig who carries out work that would otherwise distract more skilled workers.
- Saturated Steam - The point (temperature and pressure) when steam is in contact with the liquid water (boiling) it came from. This steam contains small quanities of water and is considered to be wet steam.
- Screen Pipe Pipe perforated to permit oil and fine sand to be pumped from the well, but which excludes all large matter such as gravel which might choke up the pump valves.
- Sea Star - A semi-submersible type of oil rig used for depths of up to 3500 feet. The oil rig rests on hollow barges in a star configuration which is attached to the sea bed with tension legs that allow for a bit of movement due to rough weather.
- Shot Drill - A boring drill using chilled steel shot as an abrasive after the manner of a diamond drill; an earth-boring drill using steel shot as an abrasive.
- Sour Crude - Has a sulfur content of greater than 0.5% by weight.
- Sour Gas - Sour gas is natural gas or any other gas containing significant amounts of hydrogen sulphide (H2S). It is extremely poisonous, highly corrosive, explosive, colourless, and foul smelling. The higher the sulphide content, the more the processing steps required during refining. Sweet crude generally has very little or trace amounts of the sulphide, although sour crude has higher sulphide content.
- Specific Gravity - The density or ratio of any substance to another substance. It sometimes may be called just gravity or relative density. When calculating the specific gravity of a liquid or solid, water is normally the comparison (water has a specific gravity of 1).
- Specific Heat - The amount of energy required to increase one gram of a substance by 1 degree celsius.
- Splash Plate - A splash plate, inlet diverter or inlet deflector takes the inlet flow and causes it to change direction suddenly.
Spot Market - Short term, non-regulated, arms length contract sales of natural gas, crude oil, refined products, or liquid petroleum gas.
- Stack Gas - Anything that comes out of a burner stack in gaseous form, usually consisting of mostly nitrogen and carbon dioxide.
- Steam - The invisible vapor (gas) when water is heated to its boiling point and passes from a liquid to a gaseous state.
- Steam Injection - An improved recovery technique in which steam is injected into a reservoir to reduce the viscosity of the crude oil.
- Storage Tank - Used to store volumes of fluids for storage or as part of a process.
- Strainer - Closed vessels that collect solid particles to be separated while passing a fluid through a removable screen.
- String - The drill string provides drilling fluid via the mud pumps to the drill bit. The fluid can be pumped down through the string and back up through the annulus which is the void between the drill string and casing.
Stripper Column - A loose designation applied to a distillation column in which light components are stripped from a heavier liquid product.
Stripping - The removal of the more volatile components from a cut or fraction.
Stripping Zone - The section of the column in which light components are stripped from a heavier liquid product. In conventional distillation columns, this is the portion of the column from the reboiler to the feed tray.
- Structural - Uses physics principles and materials to designs projects like bridges, buildigs, industrial facilities and tunnels. Structural engineers are responsible for the stability of the buildings and facilities, not the design or looks like an architect.
- Sulfur - A yellowish nonmetallic element, sometimes known as brimstone. It is present at various levels of concentration in many fossil fuels whose combustion releases sulfur compounds that are considered harmful to the environment.
- Sulfur Dioxide - A major component of a group of airborne contaminants termed acidifying emissions.
- Sweet Crude - Has a sulfur content of less than 0.5% by weight.
Sweet Gas - All natural gas except sour gas and casinghead gas.
- Synthetic Crude - Wide boiling range product of catalytic cracking, coking, hydrocracking, or some other chemical structure change operation.
- Synthesis Gas - The product of a reforming operation in which a hydrocarbon usually methane and water are chemically rearranged to produce carbon monoxide, carbon dioxide and hydrogen. The composition of the product stream can be varied to fit the needs of hydrogen and carbon monoxide at refineries or chemical plant.
Tail Ends - Small amounts of hydrocarbon in a cut that vaporizes slightly outside the effective initial boiling point and the effective end point.
- Tail Gas - The lightest hydrocarbon gas released from a refining process.
- Tail Gas Treating Unit - Refinery process unit used to control emissions of sulfur compounds; generally integrated with a sulfur recovery unit.
- Tank Farm - A term applied to a battery of storage tanks.
- Tank Station - A tank farm located alongside of a pipeline.
- Temporary Strainer - A startup strainer, also known as a witch’s hat or conical strainer, in installed in a system to remove unwanted debris from the process stream. It can be installed to protect a flow meter, pump, control or relief valves or other pieces of equipment during startup.
- Tank Battery - A group of tanks at a well site used to store oil prior to sale to a pipeline company.
- Tar Sands - Mixture of sand, water, and heavy hydrocarbons, where the petroleum which can be extracted requires expensive processing.
- Thermal Conductivity - The ability to transfer heat within a material without any motion of the material. Depending on the material, the transfer rate will vary. The lower the conductivity, the slower the transfer. The higher the conductivity, the faster the transfer.
- Thermal Cracking - Conversion of heavy oil molecules into lighter fractions by the use of high temperatures without the aid of catalysts.
- Thermal Expansion - The increase in length, area or volume due to the increase (in some cased decrease) in temperature.
- 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.
- Topsides - Facilities designed for the production of oil & gas in an offshore environment. Topsides are designed to sit on a fixed or floating base. Topsides may include equipment or facilities for drilling, production, and/or accommodation of offshore personnel.
- Tot Tap - Tapping into a pipeline to add a new section of pipe, a branch, valve or pump.
- Transmission Pipeline - When not specified includes both hazardous liquids and natural gas transmission pipelines. These pipelines carry oil, petroleum products, natural gas, natural gas liquids, anhydrous ammoia and carbon diozide from producing regions of the country to markets.
- Transmission Pipeline Corridor - A linear area where pipeline systems are closely grouped in a single right-of-way.
Treat Gas - Light gases, usually high in hydrogen content, which are required for refinery hydrotreating processes such as hydrodesulfurization. The treat gas for hydrodesulfurization is usually the tail gas from catalytic reforming or the product from a hydrogen unit.
- Turbine Oil - A well refined, selected petroleum distillate, or mixture of such with a bright stock, used for lubricating steam turbines. These oils show high resistance to emulsification with water and to oxidation under conditions of use.
- Turnaround - A planned complete shutdown of an entire process or section of a refinery, or of an entire refinery to perform major maintenance, overhaul, and repair operations and to inspect, test, and replace pro- cess materials and equipment.
- Unlined Pit - The ground is excavated to create a dugout to store fresh water.
- Upstream - A sector of the petroleum industry referring to the searching for, recovery and production of crude oil and natural gas. Also known as the exploration and production sector.
- Vacuun Distillation - Distillation of petroleum under vacuum, which reduces the boiling temperature sufficiently to prevent cracking or decomposition of the feedstock.
- Valve - A mechanism used to stop or open and regulate flow.
- Vapor - The gas state of a liquid or solid. Both vapor and gas are basically the same thing. Gas just happens to be the term normally used.
- Vapor Pressure - The pressure at a certain temperature when the liquid and vapor are in equilibrium. Liquid vapor pressure is measured in the laboratory at 100 degrees fahrenheit and is referred to as the Reed Vapor Pressure. As the temperature of a liquid increases, the vapor pressure also increases.
Vapor Lock - Is the phenomenon of insufficient gas- oline flow from a fuel pump due to its inability to pump the mixture that results from low pressure or high tem- perature, which has high volatility.
- Vessel Internals - Vessels have internals to help them effectively process the fluids go through it.
Virgin Stock - Petroleum oils that have not been cracked or otherwise subjected to any treatment that would produce appreciable chemical change in their components.
- Viscosity - The measure of the internal friction/resistance to the flow of a liquid. Lower viscosity fluids flow easily in pipes where high viscosity fluids have a have a higher pressure drop.
- Vortex Breaker - This is a vortex breaker installed on the outlet nozzle of a new tank. It is in the process of being coated and being sandblasted.
- Waterflood - An improved oil recovery technique that involves injecting water into a producing reservoir to enhance movement of oil to producing wells.
- Water Gas - A gas made by forcing steam over incandescent carbon (coke) whereby there results a mixture of hydrogen and carbon monoxide.
- Water Packer - A device to cut off water from the lower levels of an oil well, or to separate two distinct flows of oil from different strata.
- Wave Breaker - In long horizontal vessels it is necessary to install wave breakers or stilling baffles, which are nothing more than vertical baffles spanning the gas-liquid interface and perpendicular to the flow.
- Weir - In liquid-liquid separation, the lighter of two liquids might have an overflow weir. Using residence time, chemicals or heat, two immiscible liquids are allowed to separate.
- Well - A hole drilled to find or delimit a petroleum deposit and/or produce petroleum or water for injection purposes, inject gas, water or another medium, or map or monitor well parameters. A well may consist of one or more well paths and may have one or more terminal points.
- Wellbore - A hole drilled or bored into the earth, usually cased with metal pipe, for the production of gas or oil.
- Wellhead - The control equipment fitted to the top of the well consisting of outlets, valves, blowout preventors, etc.
- Wet Gas - Produced gas that contains natural gas liquids.
- Well Logging - Making a detailed record of the geologic formations penetrated by a borehole.
- Wildcat Well - An exploration well drilled to find out whether petroleum exists in a prospect.
Wire Rope - A rope whose strands are made of wires and twisted or woven together.
- Working Pressure - The normal pressure that a system operates at.
- Workovers - Major repairs or modifications which restore or enhance production from a well.
- Worm - A coil of pipe for condensing vapors.