ASME B31.3
Sr. No. 1
This This Proc Proces ess s Pipi Piping ng Code Code is is a Secti Section on of the the Americ American an Socie Society ty of Mechanical Engineers Code for Pressure Piping, ASME B31, an American National Standard. (i) For metallic piping not designated by the owner as Category M, High Pressur or High Purity Fluid Service (see para. 300.2 and Appendix M), Code requireme are found in Chapters I through VI (the base Code) and fluid service requiremen are found in (a) Chapter III for materials (b) Chapter II, Part 3, for components (c) Chapter II, Part 4, for joints j oints (ii) For nonmetallic piping and piping lined with nonmetals, all requirements are found in Chapter VII. (iii) For piping in a fluid service designated as Category M, all requirements are found in Chapter VIII. (iv) For piping in a fluid service designated as Category D, piping elements restricted to Category D Fluid Service in Chapters I through VII, as well as elements suitable for other fluid services, may be used. (v) For piping designated as High Pressure Fluid Service, all requirements are found in Chapter IX. These rules apply only when specified by the owner. (vi) For piping designated as High Purity Fluid Service, all requirements are found in Chapter X. (vii) (vii) Requireme Requirements nts for for Normal Normal Fluid Fluid Service Service in in Chapter Chapters s I through through VI are are applica applica under severe cyclic conditions unless alternative requirements for severe cyclic conditions are stated. (viii) Requirements for Normal Fluid Service in Chapters I through VI are applica for Elevated Elevated Temperature Fluid Service unless alternative requirements for Elevated Temperature Fluid Service are invoked.
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EXCLUSIONS This Code excludes the following: (a) piping systems designed for internal gage pressures at or above zero but less than 105 kPa (15 psi), provided the fluid handled is nonflammable, nontoxic, and not damaging to human tissues as defined in 300.2, and its design temperature is from −29°C (−20°F)
through 186°C (366°F) (b) power boilers in accordance with BPV Code2 Section I and boiler external piping which is required to conform to B31.1 (c) tubes, tube headers, crossovers, and manifolds of fired heaters, which are internal to the heater enclosure (d) pressure vessels, heat exchangers, pumps, compressors, and other fluid handling or processing equipment, equipment, including internal piping and connections for external piping 3
Design Temperature The design temperature of each component in a piping system is the temperatu at which, under the coincident pressure, the greatest thickness or highest component rating is required 301.3.2 Uninsulated Components (a) For fluid temperatures t emperatures below 65°C 65°C (150°F), the component component temperature shall be taken as the fluid temperature unless solar radiation or other effects result in a higher temperature. (b) For fluid temperatures t emperatures 65°C (150°F) and above, above, unless a lower average wall temperature is determined by test or heat transfer calculation, calculation, the temperature for uninsulated components shall be no less than the following values: (1) valves, pipe, lapped ends, welding fittings, and other components having wall thickness comparable to that of the pipe: 95% of the fluid temperature (2) flanges (except lap joint) including those on fittings and valves: 90% of the fluid temperature (3) lap joint flanges: 85% of the fluid temperature (4) bolting: 80% of the fluid temperature
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Bases for Design Stresses Other Materials. Basic allowable stress values at temperature for materials other than bolting materials, cast iron, and malleable iron shall not exceed the lowest of the following: (1) the (1) the lower of one-third of ST and one-third of tensile strength at temperature (2) except (2) except as provided in (3) below, the lower of two-thirds of SY and two-thirds of yield strength at
temperature (3) for (3) for austenitic stainless stainless steels and nickel alloys having similar stress–strain behavior, the lower of twothirds of SY and 90% of yield strength at temperature [see (e) below]
(4) 100% of the average stress for a creep rate of 0.01% per 1 000 h (5) 67% of the average stress for rupture at the end of 100 000 h (6) 80% of the minimum stress for r upture at the end of 100 000 h
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Thickness Thickness calculation for Straight pipe: The required thickness of straight sections of pipe shall be determined Straight Pipe Under Internal Pressure (a) For t < D/6, D/6, the internal pressure design thickness for straight pipe shall be not less than that calculated in accordance with either eq. (3a) or eq. (3b):
(b) For t ≥ D/6 or for P/SE > 0.385, calculation of pressure design thickness for straight pipe requires special consideration consideration of factors such as theory of failure, effects of fatigue, and thermal stress.
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Allowable Displacement Stress Range, S A
When Sh is greater than S L, the difference between them may be added to the term 0.25Sh in eq. (1a). In that case, the allowable stress range is calculated by eq. (1b):
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Stress due to Sustained Load The equation for the stress due to sustained loads, loads, such as pressure and weight, S L, is provided in eq. (23a). The equation for the stress due to sustained bending moments, Sb, is provided in eq. (23b).
The equation for the stress due to sustained torsional torsional moment, St, is
The equation for the stress due to sustained longitudinal longitudinal force, Sa, is
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FLUID SERVICE:fluid service: a general term concerning the application of a piping system, considering the combination of fluid properties, operating conditions, conditions, and other factors f actors that establish the basis for design of the piping system. See Appendix Appendix M. (a) Category D Fluid Service: a fluid service in which all of the following apply: (1) the fluid handled is nonflammable, nontoxic, and not damaging to human tissues as defined in para. 300.2 (2) the design gage pressure does not exceed 1 035 kPa (150 psi) (3) the design temperature is not greater than 186°C (366°F) (4) the fluid temperature caused by anything other than atmospheric conditions is not less than −29°C (−20°F)
(b) Category M Fluid Service: a Service: a fluid service in which the potential for personnel exposure is judged to be significant and in which a single exposure to a very small quantity of a toxic fluid, caused by leakage, can produce serious irreversible harm to persons on breathing or bodily contact, even when prompt restorative measures are taken. (c) Elevated Temperature Fluid Service: a fluid service in which the piping metal temperature is sustained equal to or greater than Tcr as defined in Table 302.3.5, General Note (b). (d) High Pressure Fluid Service: a Service: a fluid service for which the owner specifies the use of Chapter IX f or piping design and construction; see also para. K300. (e) High Purity Fluid Service: a fluid service that requires alternative methods of fabrication, inspection, examination, and testing not covered elsewhere in the Code, with the intent to produce a controlled level of cleanness. The term thus applies to piping systems defined for other purposes as high purity, ultra high purity, hygienic, or aseptic. (f) Normal Fluid Service: a Service: a fluid service pertaining to most piping covered by this Code, i.e., not subject to the rules for Category D, Category M, Elevated Temperature, High Pressure, or High Purity Fluid Service.
EN 13480
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This European Standard EN 13480 for Metallic industrial piping consists piping consists of seven interdependant and non dissociable Parts which are: - Part 1: General; - Part 2: Materials; - Part 3: Design and calculation; - Part 4: Fabrication and installation; - Part 5: Inspection and testing; - Part Part 6: Additional Additional requirements for buriedd piping; CEN/TR 13480-7, Guidance on the use of confirmity confirmi ty assessment procedures This European Standard specifies the requirements for industrial piping systems and support, including safety systems, made of metallic materials (but initially restricted to steel) with steel) with a view to ensure safe operation. This European Standard is applicable to metallic piping above piping above ground, ducted or buried, irrespective of pressure.
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ble
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Calculation temperature The The calc calcul ulat atio ion n temp temper erat atur ure, e, tc, tc, shal shalll be the the maxi maximu mum m temp temper erat atur ure e like likely ly to be reac reach h piping, piping, unde underr normal normal opera operating ting conditio conditions, ns, at at the calculat calculation ion pressure pressure pc. The The calcu calcula la determine determined d as indicat indicated ed below. below. Any Any heat heat transfer transfer calcula calculation tion shall shall be be performed performed on on t heat loss due to wind. a) For externally uninsulated and internally unlined piping components , the cal follows : 1) For fluid f luid temperatures below 40 °C, the calculation temperature temperature for the component fluid temperature; 2) For fluid fluid temperatures temperatures of 40 °C and above, above, unless unless a lower average average wall temperatu temperatu or heat transfer calculation, the calculation calculation temperature for f or uninsulated components the following values, but not less than 40°C: i) 95 % of the the flui fluid d temp temper erat atur ure e for for valv valves es,, pipe pipes, s, ends ends,, weld weldin ing g fitt fittin ings gs,, and and othe otherr co wall thickness comparable to that of the pipe; ii) 90 % of the fluid temperature for flanges (except lap joint flanges) including those valves; iii) 85 % of the f luid temperature for lap joint flanges; iv) 80 % of the f luid temperature for bolting.
Steels other than austenitic steels 5.2.1.1 Design conditions The design stress shall be in accordance with the following:
where,
ReHt
= min minimum mum spe specifi cifie ed value lue of upper yield ield stre trength gth at cal cal
f
when this temperature is greater than the room temper = design stress
Rp0,2t
= mi minimum sp specified va value of of 0, 0,2 % proof st stren rength at at ca cal when this temperature is greater than the room temper
Rm
= minimum specified value of tensile strength at r oom te
Austenitic steels 5.2.2.1 Design conditions The design stress shall be in accordance with the following: for A > 35 %
where, A
Rp1,0t
= elongation at rupture = mi minimum sp specified va value of of 1, 1,0 % proof st stren rength at at ca cal when this temperature is greater than the room temper
Rm t
= minimum minimum specified specified value value of of tensile tensile strength strength at calcu calculati lati when this temperature is greater than the room temper
Time-dependent Time-dependent nominal design stress Steels 5.3.2.1 Design conditions The design stress in the creep range f CR to be used for design under static loading
where SFCR is a safety safety factor factor which which depen depends ds on the time time and and shall shall be be in accordan accordance ce with with Ta If the design design lifetime lifetime is not not specifi specified, ed, the mean creep rupture rupture strengt strength h at 200 000 h s In cases where the 200 000 h values are not specified in the material standards, the at 150 000 h or 100 000 h shall be used. In case cases s where where desig design n lifet lifetime imes s short shorter er than than 100 100 000 000 h are specif specified ied,, one one of the the foll follo o a) If a lifetime lif etime monitoring system is not provided, provided, the safety factor SF CR sha shall be equ to the mean creep rupture strength at the relevant lifetime of at least 10 000 h; b) If a lifetime lif etime monitoring system is provided, provided, a safety factor of SF CR = 1,25 may be s
mean creep rupture strength at the relevant lifetime of at least 10 000 h. In no case, shall the 1 % creep strain limit (mean value) at 100 000 h be exceed
The The min minim imum um requ requir ired ed wall wall thic thickn knes ess s for for a stra straig ight ht pipe pipe with withou outt all allow owan ance ces s and and tole tolerr as follows:
The allowable stress range f a shall be given by:
where, Ec is the the val value ue of the the mod modul ulus us of elas elasti tici city ty at the the min minim imum um meta metall tem tempe pe under consideration; Eh is the the val value ue of the the mod modul ulus us of elas elasti tici city ty at the the max maxim imum um meta metall tem temp p under consideration; f c is the basic basic allowab allowable le stress stress at minimum minimum metal metal tempera temperature ture consis consiste te U is the stress range reduction factor (see NOTE 1) taken from Table 1
NOTE 1 - U - U applies applies essenti essentially ally to to non-corro non-corroded ded piping piping.. Corrosion Corrosion can can sharply sharply decre decrea a resistant materials should be considered where where a large number of major stress cycle
Stress due to sustained loads The sum of primary stresses 1, due to calculation pressure, p c, and the resultant other sustained mechanical loads shall satisfy the following f ollowing equation:
For the purp purpose ose of classi classificat fication ion of pressu pressure re equip equipment ment in haza hazard rd categ categorie ories, s, fluids fluids ( 1) Group 1 comprises dangerous dangerous fluids fluids (under (under Council Directive 67/548/EE 67/548/EEC C (27 Jun explosive ; extremely flammable; highly flammable; flammable (where the maximum allowable temperature is above flashp toxic; oxidizing. 2) Group 2 comprises 2 comprises all other fluids not referred to in Group 1. In combi combinati nation on with the internal internal volume volume (V) (V) and/o and/orr the maximum maximum allowab allowable le pressu pressure re ( 4 specific cases: a) Flu Fluids ids in Grou Group p 1; Ind Indust ustria riall pipin piping g for for gases, gases, lique liquefie fied d gases gases,, gase gases s disso dissolve lved du vapo vapour urs s and and also also liqu liquid ids s who whose se vapo vapour ur pres pressu sure re at the the max maxim imum um allo allowa wabl ble e tem tem normal atmospheric pressure (1013 mbar),within the following following limits: DN > 25; b) Flu Fluids ids in Grou Group p 2; 2; Indus Industri trial al pipi piping, ng, liq lique uefie fied d gase gases, s, gase gases s diss dissolv olved ed un under der pre pres s
vapour pressure at the maximum allowable temp. is greater than 0,5 bar above within the following limits: DN > 32 and PS x DN > 1000 bar; c) Fl Flui uids ds in Gr Grou oup p 1; 1; Ind Indus ustr tria iall pip pipin ing g for for liq liqui uids ds ha havi ving ng a vap vapou ourr pre press ssur ure e at at the the m 0,5 bar bar above above normal normal atmosp atmospheri heric c pressure pressure (101 (1013 3 mbar),wi mbar),within thin the follow following ing lim lim d) Fl Flui uids ds in Gr Grou oup p 2; 2; Ind Indus ustr tria iall pip pipin ing g for for li liqu quid ids s hav havin ing g a vap vapou ourr pre press ssur ure e at at the the m 0,5 bar bar abov above e norma normall atmos atmosph pheri eric c pres pressur sure e (101 (1013 3 mbar) mbar),, with within in the the follo followin wing g li PS x DN > 5 000 bar. Indust Industria riall piping piping are are class classifi ified ed in haz hazard ard cate categor gories ies I to to Ill acco accordi rding ng to one one of the the rele rele diameter and maximum allowable allowable pressure. pressure. The classification classification has been been defined in th
ed at the mid-thickness of the tion temperature shall be e assumption that there is no
ulation temperature temperatur e shall be as shall be taken as the re is determined by test hall be not less than ponents having n fittings and
ulation temperature " t " ature
culation temperature " t "
ature perature
culation temperature " t "
ature on temperature
ature
hall be:
ble 5.3.2-1. all be used. ean creep rupture strength ing methods shall be used : l to 1,5 and shall be applied pecified with regard to the
d.
nces, e, shall be calculated
rature (t=c) consistent with the loading rature (t=h) consistent with the loading t with the loading under consideration considerati on
2.1.3-1
se cyclic lifetime. Therefore, corrosion are anticipated.
oment, M A, from weight and
as or liquid) are divided into two groups: e 1967), Article 2 (2)), i.e. fluids defined as:
oint); very toxic toxic;;
PS) of the vessel this leads to nder pressure, perature is greater than 0,5 bar above
sure, vapours and also liquids whose
normal atmospheric pressure (1013 mbar),
aximum allowable temp. of not more than its: DN > 25 and PS x DN > 2 000 bar; aximum allowable temp. of not more than its: PS > 10 bar and DN > 200 and
vant cases a) to d) and their nominal Figures A.1 to A.4.
