ASTM A350 LF2 Flanges Specification for Low Temperature Service

Grade LF2 to ASTM A350 is the most popular grade of Carbon and Low-Alloy Steel for forged fittings,flanges.

Our Flanges availability according to ASTM A350 LF2.

Grades: ASTM A350/ ASME SA350 Grade LF2, LF1, LF3, LF5, LF6, LF9, Class 1, 2, 3
Outer Diameters: 1/2” to 24” in ASME B16.5, up to 60” in ASME B16.47 Series A &B
Wall Thickness Schedule: SCH 10, SCH 40, SCH 160
Pressure Class: Class 150, 300, 600, 900, 1500, 2500
Manufacturing Standards: ASME B16.5, ASME B16.47 A, B,NACE MR 1075

Flange type:Weld neck flange,Slip on flange,Blind,Thread etc

ASTM A350  is the Standard Specification for Carbon and Low-Alloy Steel Forgings, Requiring Notch Toughness Testing for Piping Components

This specification  covers several grades of carbon and low-alloy steel forged or ring-rolled flanges, forged fittings and valves intended primarily for low-temperature service and requiring notch toughness testing. They are made to specified dimensions, or to dimensional standards, such as the ASME and API Specifications referenced in Section 2. Although this specification covers some piping components machined from rolled bar and seamless tubular materials (see 5.3.3), it does not cover raw material produced in these product forms.

ASTM A350 LF2 Manufacture

The steel shall be fully killed, fine-grain practice.

The molten steel may be vacuum treated prior to or during pouring of the ingot

ASTM A350 LF2 Forging Process:

Material for forgings shall consist of ingots, or forged, rolled, or strandcast blooms, billets, slabs, or bars. 5.3.2 The finished product shall be a forging as defined in the Terminology section of Specification A788/A788M.

ASTM A350 LF2 Heat Treatment:

Forgings of grades other than Grade LF787 shall be furnished in the normalized, or normalized and tempered, or quenched and tempered condition. At the option of the manufacturer, forgings furnished in the quenched and tempered condition may be normalized prior to the austenitize/quench operation.

ASTM A350 LF2 Chemical Composition

Heat Analysis: 1.1 A chemical heat analysis in accordance with Specification A961/A961M shall be made and conform to the requirements as to chemical composition prescribed in Table 1. Leaded steels shall not be permitted.

1.2 Product Analysis:

1.2.1 The purchaser may make a product analysis on products supplied to this specification in accordance with Specification A961/A961M.

ASTM A350 LF2 Mechanical Properties

1.1 Tension Tests:

1.1.1 Requirements—The material shall conform to requirements for tensile properties in Table 2.

1.1.1.1 The test specimen shall be obtained from a rough or finished forging, or prolongation thereof. For forgings under 10 000 lbs, at time of heat treatment, it may be obtained from separately forged test blanks from the same heat of steel as the production forgings. The test blank shall be reduced by forging in a manner similar to that for the products represented, and shall receive approximately the same hot working and reduction and the same heat treatment as the finished products represented. The test material shall be treated in the same furnace at the same time as the forging it represents, subject to the requirements of 1.1.2.1. 1.1.1.2 The test specimen shall represent all forgings from the same heat and heat-treatment load whose maximum thicknesses do not exceed the thickness of the test forging or blank by more than 1 ⁄4 in. [6 mm]. 7.1.2 Number of Tests—One tension test at room temperature shall be made in accordance with 1.1.1.2 from each heat in each heat-treatment load

ASTM A350 LF2 Impact Test:

ASTM A350 LF2 Hardness requirement

7.3.1 Except when only one forging is produced,a mini-mum of two forgings shall be hardness tested per batch or continuous run as defined in 7.1.2.1 to ensure that hardness of the forgings does not exceed 197 HBW after heat treatment for
mechanical mechanical properties. The hardness measurements shall be made as specified in Specification A961/A961M. When only one forging is produced, it shall be hardness tested to ensure that it meets the 197 HBW maximum of this specification. The purchaser may verify that this requirement has been met by testing at any location on the forging, provided that such testing does not render the forging useless.

ASTM A350 LF2 Hydrostatic Test

Forgings manufactured under this specification shall be capable of passinga hydrostatic test compatible with the rating
of the finished item. Such tests shall be conducted by the manufacturer only when Supplementary Requirement $57 of
SpecificationA 961 is specified.