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ASME B31.3-2016
<br /> BPV Code, Section VIII, Division 2, Part 3, para. 3.15; (d) Cyclic Stresses. Allowable values of alternating
<br /> or Division 3,Article KD-3; as applicable,may be used stress or equipment alternating stress, as applicable,
<br /> in fatigue analysis in accordance with para. K304.8. shall be in accordance with Section VIII, Division 2,
<br /> Part 3,para.3.15 and Part 5;or Division 3,Article KD-3;
<br /> (16) K302.3.2 Bases for Allowable Stresses. The bases respectively.
<br /> for establishing allowable stress values for materials in K302.3.3 Casting Quality Factory The casting quality
<br /> this Chapter are as follows: factor, Ec, shall be 1.00 by conformance to all of the
<br /> (a) Bolting Materials. The criteria of Section II,Part D, following supplementary requirements:
<br /> Appendix 2, para. 2-120 or 2-130, or Section VIII, (a) All surfaces shall have a roughness average, RQ,
<br /> Division 3, Article KD-6, para. KD-620, as applicable, not greater than 6.3 µm RQ(250 µin.RQ);see ASME 1346.1
<br /> apply for a definition of RQ.
<br /> (b) Other Materials. For materials other than bolting (b) All nonferromagnetic surfaces shall be examined
<br /> materials, the following rules apply: using the liquid penetrant method in accordance with
<br /> (1) Except as provided in (b)(2) below, allowable ASTM E165, with acceptability judged in accordance
<br /> stress values at design temperature for materials shall
<br /> with MSS SP-93,Table 1.All ferromagnetic surfaces shall
<br /> be examined using either the liquid penetrant method
<br /> not exceed the lower of two-thirds of Sy and two-thirds or the magnetic particle method, in accordance with
<br /> of Syt. Syt is determined in accordance with eq. (31) ASTM E165 or ASTM E709, respectively. Acceptability
<br /> of imperfections,including those in weld repairs, shall
<br /> be judged in accordance with MSS SP-93, Table 1 or
<br /> Syt = SYRY (31) MSS SP-53, Table 1,respectively.
<br /> (c) Each casting shall be fully examined either ultra-
<br /> where sonically in accordance with ASTM E114 or radiographi-
<br /> RY = ratio of the average temperature dependent cally in accordance with ASTM E94.Cracks and hot tears
<br /> (Category D and E discontinuities in accordance with the
<br /> trend curve value of yield strength to the room standards listed in Table K302.3.3D) and imperfections
<br /> temperature yield strength whose depths exceed 3% of nominal wall thickness are
<br /> Sy = specified minimum yield strength at room not permitted. Acceptable severity levels for radio-
<br /> temperature graphic examination of castings shall be in accordance
<br /> Syt = yield strength at temperature with Table K302.3.3D.
<br /> K302.3.4 Weld Joint Quality Factor. Piping compo-
<br /> (2) For solution heat treated austenitic stainless nents containing welds shall have a weld joint quality
<br /> factor Ej = 1.00(see Table 302.3.4),except that the accept-
<br /> steels and certain nickel alloys with similar stress-strain �
<br /> behavior, allowable stress values shall not exceed the ance criteria for these welds shall be in accordance with
<br /> lower of two-thirds of Sy and 90% of Syt. para. K341.3.2. Spiral (helical seam) welds are not
<br /> Application of stress values so determined is not rec- permitted.
<br /> ommended for flanged joints and other components in K302.3.5 Limits of Calculated Stresses Due to
<br /> which slight deformation can cause leakage or malfunc- Sustained Loads and Displacement Strains
<br /> tion. [These values are shown in italics or boldface in (a) Internal Pressure Stresses. Stresses due to internal
<br /> Table K-1, as explained in Note (12) to Appendix K pressure shall be considered safe when the wall thick-
<br /> table.]Instead,either 75%of the stress value in Table K-1 ness of the piping component,and its means of stiffen-
<br /> or two-thirds of the yield strength at temperature listed ing, meet the requirements of para. K304.
<br /> in Section II, Part D, Table Y-1, as applicable, should (b) External Pressure Stresses. Stresses due to external
<br /> be used. pressure shall be considered safe when the wall thick-
<br /> (c) Unlisted Materials. For a material that conforms to ness of the piping component,and its means of stiffen-
<br /> para.K323.1.2,allowable stress values at design temper- ing, meet the requirements of para. K304.
<br /> ature shall not exceed the lower of two-thirds of Sy and (c) Longitudinal Stresses,SL. The sum of the longitudi-
<br /> two-thirds of Syt. nal stresses SL in any component in a piping system due
<br /> to sustained loads, such as pressure and weight, shall
<br /> (1) Except as provided in (c)(2) below, Syt shall be
<br /> y not exceed Sh in (d) below. The thickness of pipe used
<br /> determined in accordance with eq. (31). in calculating SL shall be the nominal thickness minus
<br /> (2) If the yield strength at temperature for an mechanical, corrosion, and erosion allowance, c.
<br /> unlisted material is contained in Section II, Part D,
<br /> Table Y-1,that yield strength at temperature value may 1 See Notes to Tables 302.3.3C and 302.3.31)for titles of standards
<br /> be used directly in the determination of allowable stress. referenced herein.
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