Specified minimum yield strength

Plates, Shapes, and Bar Stock. Structural material used in the manufacture of main load carrying components of the equipment shall conform to applicable ASTM or API specifications covering steel shapes, plates, bars, or pipe, or a proprietary specification conforming to the minimum requirements of applicable ASTM or appropriate standard. Structural steel shapes having a specified minimum yield strength less than 33,000 psi, or steel pipe having a specified minimum yield strength less than 35,000 psi shall not be used. 

Pipe Body Yield Strength (Section 2 of API 5C3). Pipe body yield strength is the axial load required to yield the pipe. It is taken as the product of the cross-sectional area and the specified minimum yield strength for the particular grade of pipe. Values for pipe body yield strength were calculated by means of the following formula ... 

When establishing test pressures for a test section, the maximum test pressure shall be determined by the operator to prevent damage to the pipeline and its components. Consideration must be given to the effect of test section elevation differences on the test pressure. Whenever test pressure will cause a hoop stress in excess of 100% of the specified minimum yield strength (SMYS), refer to Nonmandatory Appendix C for guidance on yield monitoring. The minimum test pressure shall be as required by (a) through (c) below. 

GR-5.21 REPAIR, TESTING, AND EXAMINATION OF MAINS OPERATING AT HOOP STRESS LEVELS AT OR ABOVE 30% OF THE SPECIFIED MINIMUM YIELD STRENGTH... 

The maximum permitted value for the combined biaxial stress is kST, where S is the specified minimum yield strength per para. PL-3.7.1(a), T is the temperature derating factor per Table PL-3.7.1(g), and k is defined in (b) and (c) below. 

Sm is the maximum allowable operating stress, calculated as specified minimum yield strength x Hf, where Hf is the material performance factor from Mandatory Appendix IX, Table IX-5A or IX-5B. Material performance factors account for the adverse effects of hydrogen gas on the mechanical properties of carbon steels used in the construction of pipelines. 

S = specified minimum yield strength, psi, stipulated in the specifications under which the pipe was purchased from the manufacturer or determined in accordance with (c) below. The specified minimum yield strengths of some of the more commonly used pipeline steels whose specifications are incorporated by reference herein are tabulated for convenience in Table IX-1B. 

Limitations on Specified Minimum Yield Strength, S, in Para. PL-3.7.1(a)... 

PL-3.7.6 Pipe Surface Requirements Applicable to Pipelines and Mains to Operate at a Hoop Stress of 20% or More of the Specified Minimum Yield Strength... 

Sy Specified minimum yield strength at room temperature MPa ksi... 

This table is split into two tables by usage Table IX-l A, Basic Allowable Stresses in Tension for Metal Piping Materials and Table IX-1B, Specified Minimum Yield Strength for Steel Pipe Commonly Used in Pipeline Systems. 

Table IX-1B Specified Minimum Yield Strength for Steel Pipe Commonly Used in Pipeline Systems...

Pipeline stress level of 20% or less of the specified minimum yield strength of the live pipe ... 

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