SUPERSEDED (click for Active standard)
1.1 This specification covers forged carbon and alloy steel flanges intended primarily for petroleum and gas pipelines in areas subject to low ambient temperatures. Included are flanges to specified dimensions or to dimensional standards such as those MSS, ASME, and API specifications that are referenced in Section 2.
1.2 Supplementary requirements are provided for use when additional requirements are desired. These shall apply only when specified individually by the purchaser in the order.
1.3 Eight grades, four yield-strength classes, and three different notch toughness levels are included.
1.4 The availability of a particular size of flange of a specific grade and class is limited only by the capability of the composition to meet the specified mechanical property requirements. However, current practice normally limits the following:
|(a) (a) Grade L1 to Classes 1 and 2,|
|(b) (b) Grade L2 to Classes 1, 2, and 3,|
|(c) (c) Grade L3 to Classes 1, 2, and 3,|
|(d) (d)Grade L4 to Classes 1, 2, and 3,|
|(e) (e) Grade L7 to Classes 1 and 2, and|
|(f) (f)Grades L5, L6, and L8 are generally available in any class.|
1.5 This specification is expressed in both inch-pound units and in SI units. However, unless the order specifies the applicable "M" specification designation (SI units), the material shall be furnished to inch-pound units.
1.6 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
AWS StandardsA 5.5 Low-Alloy Steel Covered Arc-Welding Electrodes Available from American Welding Society (AWS), 550 NW LeJeune Rd., Miami, FL 33126, http://www.aws.org.
A388/A388M Practice for Ultrasonic Examination of Steel Forgings
A788/A788M Specification for Steel Forgings, General Requirements
A961/A961M Specification for Common Requirements for Steel Flanges, Forged Fittings, Valves, and Parts for Piping Applications
API Standard605 Large Diameter Carbon Steel Flanges Available from American Petroleum Institute (API), 1220 L. St., NW, Washington, DC 20005-4070, http://api-ec.api.org.
ASME Boiler and Pressure Vessel CodeSection IX Section VIII Division I, Part UG-84 Available from American Society of Mechanical Engineers (ASME), ASME International Headquarters, Two Park Ave., New York, NY 10016-5990, http://www.asme.org.
ASME StandardB 16.5 Dimensional Standards for Steel Pipe Flanges and Flanged Fittings
ICS Number Code 23.040.60 (Flanges, couplings and joints)
UNSPSC Code 40170000(Pipe piping and pipe fittings)
ASTM A707 / A707M-00a, Standard Specification for Forged Carbon and Alloy Steel Flanges for Low-Temperature Service, ASTM International, West Conshohocken, PA, 2000, www.astm.orgBack to Top