UA-69298255-1 UA-69298255-2 CSA Z662 Definitions

CSA Z662 Definitions

June 13, 2020

2.2 Definitions
     There is a commentary available for this Clause.
The following definitions shall apply in this Standard.
Above-grade installation — installation of a pipeline above the surface of the ground on supports or in 
an embankment constructed from earth or other materials.
Allowable stress — see Stress, allowable.
Ambient temperature — see Temperature, ambient.
Applicator — the company responsible for the actual application of the coating systems.
Arc burn — a localized condition or deposit that is caused by an electric arc and consists of remelted metal, heat-affected metal, a change in the surface profile, or a combination thereof.
Axial stress — see Stress, axial.
Bar-hole survey — see Survey, bar hole.
Bond — a metallic connection that provides electrical continuity.
Bond, interference — a metallic connection designed to control electrical current interchange between metallic systems.
Bottle — a gas-tight vessel that is completely fabricated from pipe with integral drawn, forged, or spun end closures and tested in the manufacturer’s plant.
Bottle-type holder — see Holder, bottle-type.
Buckle — a diamond-shaped inward and outward deformation of a pipe wall caused by any combination of bending, axial, and torsional loads.
Buckle arrester — a device or element that acts to stop the advance of a propagating buckle.
Carbon dioxide (CO2) pipeline — a pipeline conveying carbon dioxide or predominantly carbon dioxide mixtures as a liquid or in its dense phase.
Note: Dense phase refers to the physical state of a fluid above the critical pressure, including the supercritical 
Cast iron — all forms and types of cast iron, including ductile cast iron.
Cast iron, ductile — a cast iron in which the graphite present is substantially spheroidal or nodular in shape and the iron is essentially free from other forms of graphite.
Note: Also known as spheroidal graphite or nodular cast iron.
Cathodic protection — a technique to prevent the corrosion of a metal surface by making that surface the cathode of an electrochemical cell.
Cement-mortar lining — a mixture composed primarily of cement, sand, and water, shop-applied on the internal surface of line pipe or fittings.

Class location — a geographical area classified according to its approximate population density and other characteristics that are considered when designing and pressure testing piping to be located in the area.
Class location assessment area — a geographical area that extends 200 m on both sides of the 
centreline of the pipeline.
Class location assessment area, undeveloped — a class location assessment area that is
a) at least 400 m long;
b) free of dwelling units, other buildings intended for human occupancy, places of public assembly, and industrial installations; and
c) unlikely to be developed.
Class location end boundary — the demarcation between different class locations.
Cold-spring factor — the amount of cold spring that is provided, divided by the total computed thermal expansion.
Cold-springing — the fabrication of piping to an actual length shorter than its nominal length so that it is stressed in the installed condition, thus compensating partially for the effects produced by expansion due to an increase in temperature.
Collapse — cross-sectional instability of pipe resulting from combinations of bending, axial loads, and 
external pressure.
Company — the individual, partnership, corporation, or other entity that is in charge of design, materials, or construction, whichever is applicable.
Note: The company may act through an authorized representative.
Company, operating — the individual, partnership, corporation, or other entity that operates the pipeline system.
Competent — qualified, trained, and experienced to perform the required duties.
Component — a pressure-retaining member of the piping, other than pipe.
Compressor station — a facility used primarily to increase the pressure in a gas pipeline system, including
a) piping;
b) auxiliary devices (e.g., compressors, drivers, control instruments, enclosures, ventilating equipment, and utilities); and
c) any associated buildings other than residences.
Construction — all activities required for the field fabrication, installation, pressure testing, and commissioning of piping.
Contractor — the prime contractor and any subcontractors engaged in work covered by this Standard.
Control piping — see Piping, control.
Corrosion, stray current — corrosion resulting from direct current flow through paths other than the intended circuit.
Crossing, water — the crossing by an onshore pipeline of a bay, lake, river, or major stream.

Current, impressed — direct current supplied by a device employing a power source external to the electrode system.
Current, interference — see Current, stray direct.
Current, stray direct — current flowing through paths other than the intended circuit.
Customer’s meter — see Meter, customer’s.
Damage incident — an event that results in damage to a pipe, component, tank, or coating without release of service fluid.
Deactivated piping — see Piping, deactivated.
Defect — an imperfection of sufficient magnitude to warrant rejection based upon the requirements of this Standard.
Demonstrate — verify, or describe and explain, by the use of records, measurements, tests, comparison of specimens, experiments, or analysis by a competent person, supported by documentation.
Dent — a depression caused by mechanical damage that produces a visible disturbance in the curvature of the wall of the pipe or component without reducing the wall thickness.
Design operating stress — see Stress, design operating.
Diameter, outside — the specified outside diameter (OD) of the pipe, excluding the manufacturing tolerance provided in the applicable pipe specification or standard.
Distribution line — see Line, distribution.
Distribution system, gas — the main and service lines, and their associated control devices, through which gas is conveyed from transmission lines or from local sources of supply to the termination of the operating company installation as illustrated in Figure 12.1.
Distribution system, low-pressure — a gas distribution system in which the operating pressure does not exceed 14 kPa.
Ductile cast iron — see Cast iron, ductile.
Effective pipe stiffness — the effective stiffness of a pipe, taking into account localized deformations, weight-coating, field joints, and attachments.
Electrical isolation — the condition of being electrically isolated from other metallic structures and the environment.
Engineering assessment — a documented assessment of the effect of relevant variables upon fitness for service or integrity of a pipeline system, using engineering principles, conducted by, or under the direct supervision of, a competent person with demonstrated understanding and experience in the application of the engineering and risk management principles related to the issue being assessed.
Note: General requirements for engineering assessment are specified in Clause 3.3.
Engineering critical assessment — an analytical procedure, based upon fracture mechanics principles that allows determination of the maximum tolerable sizes for imperfections in fusion welds.

Fabricated assembly — an arrangement of piping that is joined together prior to installation in the pipeline system and contains at least two components that are separated by a distance of less than 10 pipe diameters.
Failure incident — an unplanned release of service fluid.
Fluid, service — the fluid contained, for the purpose of transportation, in an in-service pipeline system.
Foreign structure — any structure that is not part of the operating company’s pipeline system.
Gas detector survey — see Survey, gas detector.
Gas distribution system — see Distribution system, gas. 
Gathering line — see Line, gathering.
Gouge — a surface imperfection caused by mechanical removal or displacement of metal that reduces the wall thickness of a pipe or component.
Grade installation — installation of a pipeline on the surface of the ground or in a shallow ditch.
Note: The pipeline may be covered with earth or other materials in the form of a berm.
Ground temperature — the temperature of the earth, river bottom, or lake bottom at pipe depth.
Hazard — a condition or event that might cause a failure or damage incident or anything that has the potential to cause harm to people, property, or the environment.
Heat-affected zone (HAZ) — that portion of a weld consisting of base metal that has not been melted but whose microstructure or mechanical properties have been altered by the heat of welding.
Heat fusion joint — see Joint, heat fusion.
High energy joining (HEJ) — explosion welding of aluminum piping.
High-vapour-pressure (HVP) pipeline system — a pipeline system conveying hydrocarbons or hydrocarbon mixtures in the liquid or quasi-liquid state with a vapour pressure greater than 110 kPa absolute at 38 °C, as determined using the Reid method (see ASTM D323).
Holder, bottle-type — any bottle or group of interconnected bottles installed at one location and used for the sole purpose of storing gas.
Holder, pipe-type — any pipe or group of interconnected pipes installed at one location and used for the sole purpose of storing gas.
Holiday — a discontinuity of the protective coating that exposes the metal surface.
Hoop stress — see Stress, hoop.
Horizontal directional drilling (HDD) — a trenchless method of installing pipe in the ground at variable angles using a guidable drill head.
Hot tap — a branch connection made to piping while it is under pressure.
Hyperbaric dry chamber welding — see Welding, hyperbaric dry chamber.

Imperfection — a material discontinuity or irregularity that is detectable by inspection as specified in this Standard.
Impressed current — see Current, impressed.
Indication — evidence obtained by nondestructive inspection.
Inspection, non-destructive — the inspection of piping to reveal imperfections, using radiographic, ultrasonic, or other methods that do not involve disturbance, stressing, or breaking of the materials. 
Note: Direct visual inspection is not considered a form of non-destructive inspection.
Instrument piping — see Piping, instrument.
Integrity management program — a documented program that specifies the practices used by the operating company to ensure the safe, environmentally responsible, and reliable service of a pipeline system.
Note: An example of items to be included in an integrity management program is provided in Annex N.
Interference bond — see Bond, interference. 
Interference current — see Current, stray direct. 
Isolating valve — see Valve, isolating.
Joint, electrofusion — a joint made in thermoplastic piping using electrical energy where the heating element is an integral part of the fitting, such that when electric current is applied, the heat produced melts the mating surfaces, causing them to fuse together. The heating element is moulded into the fitting or is inserted as part of a multi-stage manufacturing process, or employs a plastic material that is an electrical semiconductor.
Joint, heat fusion — a joint made in thermoplastic piping by heating the parts sufficiently to enable fusion of the materials when the parts are pressed together.
Joint, mechanical interference fit — a non-threaded joint for metallic pipe involving the controlled plastic deformation and subsequent mating of the pipe ends, or the mating of the pipe ends with a coupling; the resultant joint is achieved through the interference fit between the mated parts.
Leakage survey — see Survey, leakage. 
Leak test — see Test, leak.
Life cycle — in a pipeline system, the period of time including design, procurement, construction, operation, and abandonment.
Line, distribution — a pipeline in a gas distribution system that conveys gas to individual service lines or other distribution lines.
Line, gathering — a pipeline that conveys gas from a wellhead assembly to a treatment plant, transmission line, distribution line, or service line.
Line, service — a pipeline in a gas distribution system that conveys gas from a gathering line, transmission line, distribution line, or another service line to the customer.

Line, transmission — a pipeline in a gas transmission system that conveys gas from a gathering line, treatment plant, storage facility, or field collection point in a gas field to a distribution line, service line, storage facility, or another transmission line.
Liner — a tubular product that is inserted into buried piping to form a corrosion-resistant barrier or separate, free-standing, pressure-retaining piping.
Longitudinal stress — see Stress, longitudinal.
Long-term hydrostatic strength — see Strength, long-term hydrostatic.
Lower explosive limit (LEL) — the smallest proportion of flammable gas mixed with air that would result in combustion when exposed to a source of ignition.
Low-pressure distribution system — see Distribution system, low-pressure.
Low-vapour-pressure (LVP) pipeline system — a pipeline system conveying
a) hydrocarbons or hydrocarbon mixture in the liquid or quasi-liquid state with a vapour pressure of 110 kPa absolute or less at 38 °C, as determined using the Reid method (see ASTM D323);
b) multiphase fluids; or
c) oilfield water.
Maximum combined effective stress — see Stress, maximum combined effective. 
Maximum operating pressure — see Pressure, maximum operating.
Measuring station — a facility used to measure the quantity of service fluid flowing through piping, including meters, controls, piping, buildings, and other appurtenances.
Mechanical connector — a device or element, other than a threaded joint, used to join pipe ends by a mechanical process.
Mechanical interference fit joint — see Joint, mechanical interference fit.
Mechanical repair sleeve — equipment that can be installed over a leak to reduce or stop the leak.
Meter, customer’s — a meter that measures gas delivered to a customer.
Monitor regulator — see Regulator, monitor.
Multiphase fluid — oil, gas, and water (in liquid and/or vapour form) in any combination produced from one or more oil wells, or recombined oil well fluids that possibly have been separated in passing  through surface facilities.
Nominal wall thickness — see Wall thickness, nominal. 
Nondestructive inspection — see Inspection, nondestructive.
NPS — nominal pipe size, a dimensionless abbreviation followed by the numerical portion of the previously used inch nominal size of the matching pipe to designate the nominal size of components.
Offshore pipeline — see Pipeline, offshore.

Oilfield water — fresh or salt water transported by pipeline, regardless of purity or quality, from wells or surface locations for the purpose of
a) providing water injection to underground reservoirs;
b) disposing of waste water from hydrocarbon production, processing, or storage facilities; or
c) transporting water to or between production facilities, process facilities, or terminals.
One-atmosphere welding — see Welding, one-atmosphere. 
Operating company — see Company, operating.
Operating stress — see Stress, operating. 
Outside diameter — see Diameter, outside.
Overpressure protection — the use of pressure-limiting systems or pressure-relieving systems, or both, to continuously and automatically protect piping from fluid pressures in excess of a predetermined value.
Permafrost — the thermal condition in soil or rock at temperatures below 0 °C persisting over at least two consecutive winters and the intervening summer, whether or not moisture in the form of water or ground ice is present.
Pipe — a tubular product made to a pipe specification or standard, or tubing that is allowed by this Standard to be used as pipe.
Pipeline — those items through which oil or gas industry fluids are conveyed, including pipe, components, and any appurtenances attached thereto, up to and including the isolating valves used at stations and other facilities.
Pipeline emergency — an event involving a pipeline system, such as an uncontrolled release of service fluid, that endangers one or more of the following:
a) life;
b) the well-being and health of people;
c) property; and
d) the environment.
Pipeline, high temperature — a pipeline with a design temperature exceeding 230 °C
Pipeline, offshore — a pipeline that is installed seaward of the ordinary high water mark or from a similar point on the shoreline of major inland water.
Pipeline, steam distribution — a pipeline with a design temperature exceeding 120 °C in an oilfield thermal recovery scheme that conveys steam from a steam generation facility to steam injection wells / well pad facilities.
Pipeline system — pipelines, stations, and other facilities required for the measurement, processing, storage, gathering, transportation, and distribution of oil or gas industry fluids.
Note: See Figures 1.1, 1.2, and 12.1.
Pipe-type holder — see Holder, pipe-type.
Piping — a portion of a pipeline system, consisting of pipe or pipe and components.
Piping, abandoned — piping that is permanently taken out of service.

Piping, control — the piping used to interconnect air-, gas-, or hydraulic-operated control apparatus, or instrument transmitters and receivers.
Piping, deactivated — piping that is taken out of service and maintained for potential return to service.
Piping, instrument — the piping used to connect instruments to main piping, to other instruments and apparatus, or to measuring equipment.
Piping, pretested — piping that has been subjected, prior to being installed, to a pressure test as specified in this Standard.
Piping, sample — the piping used for the collection of samples of gas, steam, water, or oil.
Position welding — see Welding, position.
Pressure — gauge pressure, unless absolute pressure is specifically stated.
Pressure-containment repair sleeve — a full-encirclement repair sleeve that has the ability to contain pipeline pressure within the sleeve.
Pressure-control system — a device or system installed for the purpose of regulating or limiting the pressure in piping, either automatically or by continuous monitoring with manual intervention (e.g., systems that use pressure regulators, pressure-control valves, or speed control of a pump or compressor).
Pressure-limiting system — a device or system that will automatically act to reduce, restrict, or shut off the supply of fluid flowing into piping in order to prevent the fluid pressure from exceeding a predetermined value (e.g., systems that use pressure-activated on/off control of a pump or compressor, pressure-limit override on a control valve, automated pressure-activated isolation valves, or monitoring regulators).
Pressure, maximum operating (MOP) — the maximum pressure at which piping is qualified to be 
Pressure-regulating station — a facility used to control or limit the pressure within piping, including controls, piping, buildings, and other appurtenances.
Pressure-relieving system — a device or system that automatically operates to actively limit or lower the piping pressure by dumping, flaring, or blowing down the pressurized fluid into containment or the atmosphere (e.g., systems that use pressure-activated blowdown valves, pressure-relief valves, or rupture discs).
Pressure, standard service — the gas pressure to be maintained at the inlet of a domestic customer’s meter under normal operating conditions.
Pretested piping — see Piping, pretested. 
Production welding — see Welding, production.
Pump station — a facility used to pump oil industry fluids, including pumps, drivers, controls, piping, and other appurtenances.

Regulator, monitor — a pressure regulator set in series with the working-pressure regulator, for the purpose of taking over the control of the downstream pressure in the case of malfunction of the working-pressure regulator.
Regulator, service — a regulator installed on a service line to control the pressure of the gas delivered to the customer.
Reverse current switch — a device that prevents the reversal of direct current through a metallic conductor.
Ripple — a permanent localized deformation of a pipe wall characterized by several alternating low- amplitude inward/outward lobes.
Riser — the section of piping, together with its supports, integrated components, and corrosion protection system, commencing at a point 100 m from any offshore structure and ending above the water-line on the structure.
Risk management — the integrated process of risk assessment and risk control.
Road — a generic term denoting a highway, road, or street.
Roll welding — see Welding, roll.
Root bead — the weld bead that extends into, or includes part or all of, the region where two or more parts to be welded are closest.
Safety and loss management system — a systematic, comprehensive, and proactive process for the management of safety and loss control associated with design, construction, operation, and maintenance activities.
Sample piping — see Piping, sample.
Sea-bottom — the bottom of a body of water (sea water or fresh water) in which an offshore pipeline is situated.
Secondary stress — see Stress, secondary. 
Sectionalizing valve — see Valve, sectionalizing. 
Service fluid — see Fluid, service.
Service line — see Line, service.
Service regulator — see Regulator, service. 
Service shutoff — see Shutoff, service.
Shutoff, service — a valve or cock located in a service line between the gas distribution line and the meter.
Source of ignition — any mechanical, electrical, or other device that can produce sufficient energy and temperature to start combustion of a flammable mixture.
Specified minimum tensile strength — see Strength, specified minimum tensile. 
Specified minimum yield strength — see Strength, specified minimum yield.

Splash zone — the portion of an offshore pipeline subject to periodic wetting.
Standard service pressure — see Pressure, standard service.
Steel compression reinforcement repair sleeve — a steel reinforcement repair sleeve that produces a compressive hoop stress in the run pipe under operating conditions.
Storage vessel, pipe-type — pipe or group of interconnected pipes installed at one location and used for the primary purpose of storage.
Stray current corrosion — see Corrosion, stray current. 
Stray direct current — see Current, stray direct.
Strength, long-term hydrostatic — the estimated hoop stress in a plastic pipe wall that causes failure at an average of 100 000 h when the pipe is subjected to a constant hydrostatic pressure.
Note: The determination of this value is specified in CSA B137.0.
Strength, specified minimum tensile — the minimum tensile strength prescribed by the specification or standard to which a material is manufactured.
Strength, specified minimum yield (SMYS) — the minimum yield strength prescribed by the specification or standard to which a material is manufactured.
Strength, tensile — the stress obtained by dividing the maximum load attained in a conventional tensile test by the original cross-sectional area of the test specimen.
Note: Tensile strength is also known as ultimate tensile strength.
Strength test — see Test, strength.
Strength, yield — the stress at which a material exhibits the specified limiting offset or specified total elongation under load in a tensile test as prescribed by the specification or standard to which the material is manufactured.
Stress, allowable — the maximum combined stress allowed for the design of piping.
Stress, axial — the uniform stress component acting over the pipe cross-section in the longitudinal direction.
Note: This component is often referred to as membrane, average, or direct stress.
Stress, design operating — the calculated hoop stress developed in a pipe by the maximum expected operating pressure, based upon nominal dimensions.
Stress, hoop — the stress in the wall of a pipe or component that is produced by the pressure of the fluid in the piping, any external hydrostatic pressure, or both, and that acts in the circumferential direction.
Stress, longitudinal — the stress at any point on the pipe cross-section acting in the longitudinal direction.
Note: Longitudinal stress includes the effects of both bending moments and axial forces.
Stress, maximum combined effective — the maximum combined stress value obtained when all applicable longitudinal, circumferential, and tangential shear stresses are acting simultaneously.

Stress, operating — the stress in a pipe or structural member under normal operating conditions.
Stress relieving — the heating of a completed weldment in order to reduce stresses produced during the welding process.
Stress, secondary — the stress created in the wall of a pipe or component by loads other than internal or external fluid pressure.
Stress, tangential shear — the shear stress in the wall of a pipe or component acting in the circumferential direction on a plane perpendicular to the longitudinal axis of the piping.
Surge — a transient pressure change due to sudden variations in flow conditions.
Survey, bar hole — a gas leakage survey made by driving or boring holes at regular intervals along the route of buried piping and testing the atmosphere in the holes with a combustible-gas detector or other suitable device.
Survey, gas detector — a gas leakage survey made by testing with a combustible-gas detector the atmosphere in water valve boxes, street vaults, cracks in pavements, and other available locations where access to the soil under the pavement is provided.
Survey, leakage — a systematic survey made for the purpose of locating leaks in a pipeline system.
Survey, vegetation — a leakage survey made by observing vegetation above buried piping. 
Tank, aboveground — a tank that sits on or above the ground and is installed in a fixed location. 
Tank farm — tank facilities for the storage of liquids.
Tank, relief — a tank that provides containment for fluids released during pressure relief.
Tank, underground — a tank that is partially or completely buried.
Temperature, ambient — the temperature of the surrounding medium in which piping is situated or a device is operated.
Tensile strength — see Strength, tensile.
Test-head assembly — an assembly of pipe and components that forms a temporary facility used for pressure testing of piping.
Test, leak — a pressure test to determine whether piping leaks.
Test, strength — a pressure test to confirm the pressure-retaining capability of piping and establish the maximum operating pressure.
Tie-in — a connection between
a) two pressure test sections;
b) pretested piping and other piping;
c) new facilities and existing piping; or
d) two lengths of piping that are fixed at their opposite ends or are long enough to act as though they are so fixed.
Transmission line — see Line, transmission.

Trenchless installation — any technique, including augering, boring, directional drilling, and tunnelling, whereby pipe is installed without a continuous trench.
Tubing (tube) — a tubular product made to a tubing (tube) specification or standard.
Underwater welding — see Welding, underwater.
Undeveloped class location assessment area — see Class location assessment area, undeveloped.
Upgrading — qualifying an existing pipeline system, or portion thereof, for a higher maximum operating pressure or for a changed class location.
Utility — an irrigation system, drain, drainage ditch, sewer, underground communications cable or power line, or foreign pipeline.
Valve, isolating — a valve for isolating laterals, stations, pressure-relieving installations, and other facilities.
Valve, sectionalizing — a valve for isolating a segment of a pipeline.
Vegetation survey — see Survey, vegetation.
Ventilated space — a space where there is an effective air change by means of natural ventilation or mechanical means.
Wall thickness, nominal — the specified wall thickness of the pipe purchased.
Water crossing — see Crossing, water.
Weld — a localized coalescence of metals produced by heating the materials to the welding temperature, with or without filler metal.
Welding, direct deposition — welding performed directly on the surface of pipe for the purpose of 
restoring wall thickness and strength.
Welding, hyperbaric dry chamber — welding underwater in a dry environment provided by a chamber fitted over the items to be welded; water is displaced from the chamber by gas at ambient pressure.
Welding, one-atmosphere — welding underwater in a pressure vessel in which the absolute pressure is maintained at approximately one atmosphere, regardless of depth.
Welding, position — welding with the items being welded held stationary while the weld metal is deposited.
Welding procedure specification — a document providing, in detail, the required parameters for welding.
Welding, production — the execution of welds that are covered by this Standard and are to be part of a pipeline system.
Welding, roll — welding with the items being rotated while the weld metal is deposited at or near the top centre.
Welding, underwater — welding performed below the water surface.

Welding, wet — welding with the items being welded in the water and with no physical barrier around the welding arc.
Wet welding — see Welding, wet.
Wrinkle — a smooth, sinusoidal-shaped (i.e., continuous wave) outward and inward deformation of the pipe diameter, over a finite arc of the pipe circumference.
Note: Wrinkles are formed due to pipe wall compression caused by axial or bending loads and are typically more 
severe than a ripple.
Yield strength — see Strength, yield.

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CSA Z662 (Oil and gas pipeline systems)                                                 Piping Acronyms and Abbreviations

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