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Glossary and Standards

What each term means and what each standard that appears on faufena regulates. When a standard appears in a category or on a profile, tap it and it brings you here.

Valves

API 600: Steel gate valves, with bolted bonnet and flanged or butt-weld ends. It is the typical standard for plant and refinery gate valves, for example a 4″ series 150 gate valve.
API 602: Compact steel gate, globe and check valves, normally forged, of 4″ or smaller (in practice, up to 2″). Socket weld, threaded or flanged ends.
API 603: Thin-wall stainless steel or corrosion-resistant gate valves, classes 150 to 600.
API 623: Steel globe valves with bolted bonnet, flanged or butt-weld.
API 594: Wafer, lug, dual-plate and swing check valves with flanged or weld ends.
API 608: Metal ball valves for plant and refinery use, with flanged, threaded, socket weld or butt-weld ends.
API 609: Butterfly valves: concentric with elastomeric seat and high-performance (double and triple offset).
API 599: Metal plug valves, lubricated and non-lubricated.
API 6D: Pipeline valves: ball, gate, check and plug valves for gas and oil pipelines, with design, testing and documentation requirements. It is the standard for gas ball valves.
API 6A: Wellhead and Christmas tree equipment: valves, heads, hangers and chokes, in pressure classes from 2,000 to 20,000 psi.
API 607: Fire resistance test (fire safe) for quarter-turn valves with non-metallic seats.
ASME B16.34: Flanged, threaded and weld-end valves: pressure-temperature ratings by class, minimum wall thickness, materials and testing. It is the basis of almost all valve standards.
ASME B16.10: Face-to-face and end-to-end dimensions of valves: allows replacing one valve with another from a different manufacturer without touching the piping.
MSS SP-99: Instrumentation valves: needle and block valves for connecting pressure gauges, transmitters and other instruments.
API 526: Flanged steel pressure relief valves: dimensions, orifice sizes (letters D to T) and pressure ranges. Allows valves from different manufacturers to be interchanged.
API 520: Sizing, selection and installation of safety and relief valves and other pressure relief devices.
API 527: Seat tightness of relief valves: how much leakage is allowed before the opening pressure.
API 2000: Venting of atmospheric and low-pressure storage tanks: pressure-vacuum valves and emergency vents.
Safety and relief valve (PSV): A valve that opens by itself when pressure exceeds a set value, to protect equipment or piping. It is sized per API 520, its dimensions follow API 526 and it carries the UV stamp (ASME VIII) or V (boilers).

Pipe, flanges and fittings

ASME B31.3: Process piping: treatment plants, refineries, petrochemical plants and batteries. Defines design, materials, fabrication, testing and inspection.
ASME B31.4: Pipeline transportation systems for liquid hydrocarbons (oil and products pipelines).
ASME B31.8: Pipeline systems for gas transportation and distribution (gas pipelines). In Argentina it is complemented by ENARGAS's NAG standards.
ASME B36.10M: Dimensions and wall thicknesses (schedules) of carbon and alloy steel pipe, welded and seamless.
ASME B36.19M: Dimensions and wall thicknesses of stainless steel pipe.
ASTM A106: Seamless carbon steel pipe for high-temperature service, grades A, B and C. A106 Gr. B is the most widely used pipe in plant piping.
ASTM A53: Black or galvanized carbon steel pipe, seamless or welded, for general use.
API 5L: Line pipe for gas and oil pipelines. Grades B, X42, X52, X60, X65, X70 and others, at PSL1 and PSL2 (more demanding) levels.
API 5CT: Casing and tubing for oil and gas wells (OCTG).
ASTM A333: Seamless and welded steel pipe for low-temperature service (grade 6 is the most common).
ASTM A312: Austenitic stainless steel pipe, seamless and welded (TP304L, TP316L and others).
ASME B16.5: Flanges and flanged fittings from ½″ to 24″, classes 150, 300, 600, 900, 1500 and 2500. Defines dimensions, materials and pressure-temperature.
ASME B16.47: Large-diameter flanges, from 26″ to 60″ (series A and B).
ASTM A105: Carbon steel forgings for piping components: flanges, forged fittings and valve bodies.
ASTM A350: Carbon and low-alloy steel forgings for low temperature (grade LF2).
ASTM A182: Alloy and stainless steel forgings for flanges, fittings and valves (F11, F22, F304L, F316L, F51 duplex).
ASME B16.9: Butt-weld fittings (butt weld): elbows, tees, reducers and caps. Typically used in piping larger than 2″.
ASTM A234: Butt-weld fittings in carbon and alloy steel (WPB is the most common).
ASTM A403: Butt-weld fittings in austenitic stainless steel (WP304L, WP316L).
ASME B16.11: Forged socket weld and threaded fittings: elbows, tees, couplings, plugs, in classes 2000, 3000, 6000 and 9000. Used in piping of 2″ or smaller.
MSS SP-97: Integrally reinforced forged branch connections: weldolet, sockolet and threadolet.
MSS SP-95: Swage nipples (reducing) and bull plugs.
MSS SP-83: Steel unions class 3000, socket weld and threaded.
Socket weld (SW): Joint in which the pipe fits into a socket in the fitting and is joined with a fillet weld. Used in piping of 2″ or smaller (ASME B16.11).
Butt weld (BW): Butt welding: the beveled ends of the pipe and the fitting are welded with full penetration. It is the standard joint above 2″ (ASME B16.9).
NPT: National Pipe Thread: tapered thread for threaded pipe and fittings (ASME B1.20.1).
Spool: Section of piping prefabricated in a shop (pipe, fittings and flanges already welded) and taken to site for erection. A prefabrication shop's capacity is measured in inch-diameters of welding per month.

Stud bolts and gaskets

ASTM A193: Alloy and stainless steel stud bolts for high temperature or pressure. The B7 is the most widely used; the B7M is for sour service and the B8/B8M are stainless.
ASTM A194: Nuts for high-pressure, high-temperature stud bolts. The 2H is the one that goes with the B7 stud.
ASTM A320: Stud bolts for low-temperature service (grade L7).
ASME B16.20: Metallic gaskets for flanges: spiral-wound, RTJ (ring joint) and camprofile.
ASME B16.21: Flat non-metallic gaskets for flanges: fiber, graphite and PTFE.
ASME PCC-1: Guide for assembling bolted flanged joints: tightening sequence and torque.
RTJ (Ring Type Joint): Metallic ring gasket seated in a groove in the flange; used in high-pressure service and at the wellhead.

Pressure equipment and ASME stamps

ASME Section VIII: ASME pressure vessel code. Division 1 is the most widely used (separators, vessels, heat exchangers); Division 2 allows more optimized designs with more demanding rules and analysis.
ASME Section I: ASME code for power boilers.
ASME Section IX: Qualification of welding procedures (WPS and PQR) and welders (WPQ). Required by ASME VIII and ASME B31.3.
WPS / PQR / WPQ: WPS: welding procedure specification. PQR: record of the test that qualified it. WPQ: qualification of each welder. Done according to ASME IX (or API 1104 for pipelines).
ASME stamp: Certification granted by ASME after auditing the shop's quality system. It authorizes stamping the equipment the shop fabricates to the code. The most common are U, U2, S and T; the R is granted by the National Board.
U stamp: Pressure vessels according to ASME Section VIII Division 1.
U2 stamp: Pressure vessels according to ASME Section VIII Division 2.
S stamp: Power boilers according to ASME Section I.
T stamp: Transport tanks according to ASME Section XII.
UV / V stamp: Safety and relief valves certified according to ASME Section VIII (UV) or Section I (V, boilers).
National Board (NB) and R stamp: The National Board of Boiler and Pressure Vessel Inspectors registers stamped equipment and grants the R stamp, which authorizes repair and alteration of pressure equipment.
TEMA: Tubular Exchanger Manufacturers Association: design and fabrication standard for shell-and-tube heat exchangers (classes R, C and B).
API 660: Shell-and-tube heat exchangers for refinery, petrochemical and gas service.
API 661: Air coolers (air-cooled heat exchangers).
API 12J: Oil and gas field separators (two-phase and three-phase).
API 12K: Field indirect heaters (water or glycol bath).
API 560: Direct-fired furnaces for refinery and petrochemical service.
API 521: Pressure relief and depressuring systems: how to size headers and flares.
API 537: Flare design details for refinery, petrochemical and gas use.
FWKO (Free Water Knock Out): Separator that removes free water from the well fluid before it is treated.
Slug catcher: Equipment at a plant inlet that receives and dampens the liquid slugs arriving through a gas pipeline. It can be a vessel type (ASME VIII) or a pipe-finger type (fingers, ASME B31.8 or B31.4).
TEG (glycol dehydration): Triethylene glycol: a liquid that absorbs water from natural gas in a contactor tower; it is then regenerated by heating.
Electrostatic desalter: Equipment that separates emulsified salt water from crude oil using an electric field.

Tanks

API 650: Welded, atmospheric steel storage tanks, field-erected (in situ). It is the standard for almost all oil, water and fuel tanks.
API 653: Inspection, repair, alteration and reconstruction of existing tanks built according to API 650.
API 620: Large low-pressure storage tanks (for example, cryogenic).
API 12F: Shop-welded tanks for storing production liquids in the field (small capacities).

Rotating equipment

API 610: Centrifugal pumps for oil, petrochemical and gas service. Classifies pumps into OH (overhung), BB (between bearings) and VS (vertically suspended) types.
API 674: Reciprocating positive displacement pumps (simplex, duplex, triplex, quintuplex).
API 675: Positive displacement metering pumps (diaphragm and piston).
API 676: Rotary positive displacement pumps (screw, gear, vane, lobe).
API 617: Centrifugal and axial compressors for oil, gas and petrochemical service.
API 618: Reciprocating (piston) compressors for process service.
API 619: Rotary positive displacement (screw) compressors.
API 672: Packaged centrifugal air compressors with integral gears.
ATEX / IECEx: Certifications for electrical and mechanical equipment operating in explosive atmospheres (classified areas).

Metering and skids

LACT / ULACT: Lease Automatic Custody Transfer: unit that measures and transfers crude oil for fiscal purposes, with meter, sampler, prover and quality control (API MPMS).
API MPMS: Manual of Petroleum Measurement Standards: set of hydrocarbon measurement standards (meters, provers, sampling, calculations).
AGA 3: Natural gas measurement with orifice plates.
AGA 9: Natural gas measurement with multipath ultrasonic meters.
VRU (Vapor Recovery Unit): Unit that recovers vapors from tanks (which would otherwise be vented or flared) and compresses them for use.
Skid: Structural base on which equipment or a complete unit (vessels, piping, instruments, panel) is assembled in a shop, tested and ready to connect in the field.
EPF / TPF: Early / Temporary Production Facility: early or temporary production plant, generally rented and operated by the supplier.

Welding, testing and quality

API 1104: Welding of pipelines and related facilities: qualification of procedures, welders and inspection.
AWS D1.1: Structural steel welding code.
NDT (non-destructive testing): Tests that check welds and materials without damaging them: radiography (RT), ultrasonic (UT), magnetic particle (MT), liquid penetrant (PT), visual (VT) and positive material identification (PMI).
NACE MR0175 / ISO 15156: Materials suitable for sour service (with H2S), where ordinary steels can crack.
ISO 9001: Quality management system.
ISO 14001: Environmental management system.
ISO 45001: Occupational health and safety management system.
API Q1: Quality management system specific to manufacturers in the oil and gas industry; a requirement for using the API monogram.
API Monogram: License granted by API to mark products manufactured to an API specification (for example 6A, 6D or 5L) under an API Q1 system.

Standards are cited as a general reference; the edition and requirements that apply to each purchase are set by the customer's technical specification.