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Below is a brief description of many of the terms used in the Steel Pipe and Energy Industries.

    Below is a brief description of many of the terms used in the Steel Pipe and Energy Industries.

    AGA - American Gas Association.

    AISI - American Iron and Steel Institute.

    ANSI - American National Standards Institute. Administers and coordinates voluntary standardization and conformity assessment systems. Was formerly the ASA.

    API - American Petrolium Institute - Issues specifications for the manufacturing of oil field equipment.

    ASTM - American Society of Testing Materials.

    A53A, A53B, A53F, A106 - ASTM-specified grades of carbon-steel pipe.

    Bale - Banded lifts of pipe.

    Barlow's Formula - Used to estimate burst pressure of pipes or tubes. Useful in determining the wall thickness required for pipe.

    Barrel - The standard unit of measure of liquids in the petroleum industry. Contains 42 U.S. standard gallons.

    BOE - Barrel of Oil Equivelant. The amount of energy resource (in this document, natural gas) that is equal to one barrel of oil on an energy basis.

    Bevel - Cutting or shaping on the edge of a pipe to form an angle that is not perpendicular to the length of the pipe to facilitate welding. The standard bevel for line pipe is 30°.

    Billet - A solid semi-finished round or square bar of steel that is heated and pierced to form a hollow tube for seamless pipe.

    Black Pipe - Steel pipe in which the Outer Diameter has been Lacquered (as opposed to bare or galvanized pipe).

    Box - Internal threaded end of a steel pipe.

    Brinell - A test which measures the hardness or indentation of pipe using a shaped point of specified weight.

    BTC - Buttress-threaded and coupled.

    Bundle - A number of pipe banded together for shipping. Amount per bundle vary depending upon pipe size.

    Burst - Internal pressure at which tube will yield.

    Burst Test - A hydraulic test used to determine actual yield and ultimate strength of seamless and welded steel pipe.

    Butt-weld - Joining two edges or ends of a strip of steel (Skelp) by placing one against the other and welding or fusing the edges (into a cylinder).

    Casing - Steel pipe used in oil wells to retain the walls of the drilled hole and to keep the environment and the oil from being contaminated.

    CFT - Hundred foot. Used in pricing (i.e. $520.15 / cft = $5.2015 / ft).

    Chamfer - To cut at an angle or bevel to eliminate an otherwise sharp corner. A finishing operation prior to threading.

    Chemical Properties - Normally associated with a limited number of chemical elements. Minimum or maximum limits are established in ASTM specifications.

    Cold-drawn - Pipe drawn in normal temperatures through a hardened steel or carbide die which produces closer tolerances and higher strength in the pipe.

    Coupling - A metal collar with internal threads used to join two sections of threaded pipe.

    Cut Lengths - Tubing ordered to a specified length, permitting a tolerance of a standardized fraction of an inch over but not under the specified length.

    CW - Continuous Weld. A sheet of steel is formed into a tubular shape while the steel is hot. When the two edges meet, they are fused or welded together. No additional weld material is necessary. (The tube is always further processed for C.W. tubing by cold drawing).

    CWT - Hundred weight. Used in handling and trucking pricing.

    Die Stamping - Permanent marking stamped onto pipe. Required by some specifications.

    Double Extra - Pipe weight designation (XXS). Sometimes referred to as XXH (double extra heavy).

    Drift - Minimum ID clearance of pipe is verified by pulling a mandrel of a known size through a length of pipe.

    DRL - Double Random Length. Minimum 35' average lenngth - or as defined in Specifications.

    DSAW - Double-Submerged Arc Weld.

    Ductility - The ability of steel to be deformed or altered permanently at normal temperatures without being damaged. Usually reported as elongation or reduction of area.

    Eddy Current Testing - Non-destructive testing method using eddy current flow to recognize a discontinuity in pipe.

    Elongation - The amount of permanent extension around the fracture area in a tension test. Listed as a percentage of the original gauge length (i.e. 25% in 2 inches). May also refer to the amount of extension at any stage in any process that continuously elongates steel, as in rolling.

    EMI - Electromagnetic inspection. A method used to determine wall thickness and detect imperfections in steel tubes.

    ERW - Electric Resistance Weld. A method used to manufacture electric resistance weld pipe. Typical radio frequency power for welding is supplied at 450,000 cycles/sec.

    EUE - External Upset Ends. Forging the ends of tubing and drill pipe to provide additional thickness for strengthening connections.

    EW - Electric Weld. (See ERW)

    Expanded Pipe - Pipe that has been enlarged circumferentially by mechanical or hydraulic pressure.

    Extra Strong - Standard pipe weight designation (XS). Sometimes referred to as as XH (extra heavy).

    Flattening Test - A test in which a pipe is flattened between parallel plates that are closed to a specified height.

    FLD - Full Length Drift. A test performed as part of used tubing or casing inspection. (See Drift above)

    Flush Joint - Connection with male and female threads cut directly into the pipe (as opposed to T&C). This provides the same ID and OD clearance as in the middle of the tube when lengths are joined.

    FOB - Freight On Board. The point in time at which the recipient of a shipment becomes legally responsible for the shipment. Also a common way of stating the terms of delivery for sales of goods.

    High Frequency Welding - A method used to manufacture electric resistance weld pipe. Typical radio frequency power for welding is supplied at 450,000 cycles/sec. (See ERW)

    Hot Stamp - Permanent marking placed on pipe by manufacturer per specification.

    Hydrostatic Test - A test in which the ends of a pipe are sealed and water is pumped inside to a predetermined pressure.

    I.D. - Inner Diameter or Inside Diameter of a pipe.

    Impact Test - A test to determine the behavior of materials when subjected to high rates of loading. The test may be in tension, bending, or torsion.

    Joint - A length of pipe.

    Kip - A term indicating 1000 pounds.

    Lifts - Separated segments of pipe (banded or unbanded for ease of handling).

    LS - Limited Service. Pipe that did not meet specification and is usually rejected at the mill.

    LT - Loaded Trucks. Indicates seller pays for handling.

    LTC - Long Thread and Coupling. A casing connection.

    Magnetic Particle - A non destructive method of inspection for determining the existence and extent of possible defects in steel.

    Magnetic Properties - The properties of a material that reveal its elastic and inelastic behavior when force is applied.

    Mid Weld - Two or more joints welded to form a longer joint.

    Nipple - A short length of pipe threaded on both ends (usually less than 12").

    Nominal, NOM - Specified pipe size or wall thickness. Refers to approximate ID or OD size or measurements. Wall thickness is also expressed as nominal.

    NUE - Non Upset End tubing

    O.D. - Outer Diameter of a pipe

    OCTG - Oil Country Tubular Goods

    Oiled - Pipe that has been protected with a varnish type oil on the OD for temporary corrosion protection during transit and for short term storage.

    PE - Plain End

    PEB - Plain End Beveled

    Pickling - Immersing pipe into an acid bath to remove oil and dirt.

    Pin - Threaded (male) end of pipe.

    Protector - A cap placed on the end of pipe to protect threads from handling damage

    PSI - Pounds per Square Inch

    Range, R1, R2, R3 - Lengths of casing and tubing:
    Casing Range 1: 16-25'
    Casing Range 2: 25-34'
    Casing Range 3: 34-48'
    Tubing Range 1: 20-24'
    Tubing Range 2: 28-32'

    Rockwell Hardness - Relative resistance of a steel to indentation by a diamond cone. Expressed in hardness scale units.

    SAW - Submerged Arc Weld. A method of manufacturing large diameter pipe.

    SC - Square Cut. Plain end pipe

    Schedule - Specifications of different wall thicknesses of pipe.

    SEA - Special End Area Inspection. Checking for defects at both ends of a steel tube which is being electronically inspected.

    Skelp - A piece or strip of steel with a specified thickness, width and edge from which welded pipe is made.

    SMLS - Seamless. Pipe made without welding.

    Spec - Specification

    SRL - Single Random Length. Standard weight pipe that is 16' - 22' in length or as defined in specifications.

    STC - Short Thread and Coupling

    STI - Steel Tube Institute

    STD - Standard pipe. Pipe weight designation. Normal wall thickness of line pipe (sch. 40 for 1/8 - 10" pipe).

    Stencil - Painted identification and specification markings on a pipe.

    Strip - A sheet of steel in which the length is many times its width.

    Sub - A short coupling with different types and/or sizes of ends.

    T&C - Threaded and Coupled.

    T&D - Tested and Drifted. A method of verifying the integrity of used pipe. 
    Test refers to a hydrostatic test in which the ends of a pipe are sealed and water is pumped inside to a predetermined pressure.
    Drifted - A mandrel of a known size has been pulled through the length of a pipe to verify the Inner Diameter clearance.

    TBE - Threaded Both Ends.

    Tensile Strength - The ratio of maximum load per square inch to original cross-sectional area. Also referred to as ultimate strength.

    TO - Threads only.

    Tolerance - Specified allowance in deviation of the given dimension of a finished pipe due to inaccuracies in manufacturing. As defined in ASTM or API standards.

    Tool Joint - Threaded tube, usually more thick and hard, welded onto pipe to provide joint strength and durability exceeding that of flush joint or T&C connections.

    Tube Round - A solid semi-finished round or square bar of steel that is heated and pierced to form a hollow tube for seamless pipe. (See Billet)

    Tubing - A relatively small-diameter pipe that is run into a well to serve as a conduit for the passage of oil and gas to the surface.

    Ultrasonic - A of non-destructive method testing pipe utilizing sound waves.

    Victaulic - A method of joining or coupling pipe. A groove is cut into the end of each pipe to allow a victaulic coupler to be attached.

    XH, XHY - Extra Heavy. Pipe weight designation. Pipe that is 1 ½ times as thick as standard pipe (sch. 80 for1/8 - 8" pipe ). Also referred to as as XS (Extra Strong).

    XXH, XXHY - Double Extra Heavy. Pipe weight designation. Pipe that is two times as thick as XH (for ½ - 6" pipe). Also referred to as XXS (Double Extra Strong).

    Yield Strength - The stress level at which steel exhibits permanent deformation.

Next page:
Steel designations and compositions


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