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This is a LI VE STUDY document and w ill be ch anged without not ice. The con tent m ay con tain err ors and o missions.

ASME B31.1 (2008) ASME B31.3 (2008)

Power piping : typically found in e lectric po wer ge nerati ng stati ons, i n h eatingand cooling systems

Process piping : t ypical ly foun d in petroleum rene ries, chem ical,pharmaceutical, textile a nd paper pl ants

Gas tr ansportation and distpredominantly gas

Applicable : boiler ex ternal pi ping from rst j oint up to a nd including rst bl ock

valve f or bo ilers w here:

steam or vapor i s gen erated o ver 100 kP a high temperature water over 1103 kP a an d/or temperatures of 120

Celsius

Excluding : fatigue due to p ressu re cycli ng

Exclusions :

piping syst ems pressure above 0 and l ess 105 kP a non ammable,nontoxic and not dam aging to h uman ti ssues

power boi lers covered i n BPV code and exter nal pi ping c overed i nB31.1

tubes, t ube h eaders, crossovers an d m anifolds of r ed heaters

pressure vessel s, heat exchangers, pumps

Including : fatigue d ue press ure cyc ling and therm al cycl ing

Exclusions :

pressure vesse ls, metal temperatur

Celsius (450 F )

piping beyond cus

piping in ren eries

vent piping to su b

wellhead assembl

proprietary i tems

liquid p etroleu m trdioxide and lique

Allowable s tress :

as p er t ables i n Appendix A shear t o rem ain below 8 0%, bearing to rem ain be low 160% of

allowable stress

basis are sam e as ASME section II Part D Appendix 1 excep t for

cast i ron a nd ductile ir on

Allowable s tress :

as pe r Table A-1 an d A-2

shear to rem ain be low 80%, bearing to r emain be low 160% ofallowable stress

basis f or bo lting, cast i ron, othe r m ateri al

anges due t o leakage bel ow 75%

allowable str ess of unli sted materi al ( not conforming 323.1.2) cannot be use d

Allowable str ess

as pe r t able A ppe841.116A

Materi als : material of unknown s pecication shall not be used for pressurecontaining components

Materials : m aterial of unknown s pecication shall not be used for pr essu recontaining components

Materials : m ateri al only as p

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ASME B31.1 (2008) ASME B31.3 (2008)

Quality f actor E : depending type of we ld, r adiography an d m aterial Quality factor E : depending type o f weld, r adiography an d m aterial Quality factor E

Factor y : f actor de pending Ferritic, Au stenitic, N ickel and design temperature

Factor W : we ld s treng th reduction factor Factor W : we ld streng th reduction factor

Factor f : st ress ran ge factor

Factor F : design factor

Factor T : t emperature d erati nvalues for temperature, Table

Pipe under interna l pres sure ( 104.1.2 and 104.1.4 ( in c reep )) :

P = internal desi gn pressure

D0 = outside diameter of pi pe

SE = maximum allowable st ress, i ncluding quality fact or

tm = minimum required thickness

y = coefficient t able 1 04.1.2A

A = a dditional thickne ss to com pensate thread ing, provide additional strength,corrosion allowance

W = Weld str ength r eduction factor when in creep range, i s 1 o utside creeprange (table 1 02.4.7)

Pipe under i nternal pressure (304.1.2) :

P = internal design p ressu re

D = o utside diameter of pipe

S = str ess value for materi al

E = quality factor

t = pressure d esign thickness

y = coefficient, also from table 30 4.1.1

W = Weld str ength reduc tion fact or

Pipe u nder i nternal pressu r

P = internal desi gn pressure

D = nominal out side diameter

S = specied m inimum yield s

E = lon gitudina l joint factor, ta

t = w all thickne ss

F = design factor f rom table 8

T = T emperature de rating fact

Bend under internal pressure (102.4.5): Bend under internal pressure (304.2.1): Bend under internal pressu

For cold b endsaccording table in pa ragraph

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ASME B31.1 (2008) ASME B31.3 (2008)

pipe u nder i nternal pr essure w here I for i ntrados is:

and I f or t he extrados is:

and a t sidewall I = 1 .0,

R = radi us of pi pe b end

pipe u nder i nternal pr essure w here I for i ntrados is:

and I f or t he extrados is:

and a t si dewall I = 1 .0,

R = radi us of pi pe b end

Hot bends are t o b e de signeinterna l pres sure rati ng shallseamless p ipe and the intrad

where t he t the wall thickne ss

Elbows u nder i nternal pr essure (102. 4.5):

Elbows m anufactured according standards listed in T able 12 6.1 are su itable f oruse at t he pressure-t emperature rat ings spe cied by su ch standa rds.

Elbows not accordi ng a bove standards or f or wh ich de sign for mulas an d no tgiven in the c ode sh all be based on calculations consistent wi th the designcriteria o f this cod e. Th ese ca lculat ions sh all be substan tiated b y on e o r m oreof t he means stated in A B C or D of 104. 7.2 (D oes this m ean or al low that anelbow can be ca lculated according a bend w ith u niform thickness? R eferB31.3)

Elbows u nder i nternal pressu re ( 304.2.1):

Elbows m anufactured according standards listed in T able 32 6.1 are suit able foruse at t he pressure-t emperature rat ings spe cied by su ch standa rds.

Elbows not accordi ng a bove standards or f or wh ich de sign for mulas an d no tgiven in the code shall be based on calculations consistent wit h the designcriteria o f this cod e. Th ese ca lculations sh all be substantiated b y on e o r m oreof the m eans stat ed in A B C or D o f 304.7.2, or the e lbow can be ca lculatedaccording the Bend ca lculation, refer 30 4.2.2.

Elbows un der internal pres

No sp ecic de sign rules a re li

(Does this m ean o r allow that

uniform thickness?

Miter bends under internal pressure (104.3.3): Miter bends under internal pressure (304.2.3):

1. When theta = < 2 2.5 deg than m ax. al lowable p ressu re sh all be the lesse r of

Miter ben ds u nder i nternal

1. I f system hoop str ess > 40

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ASME B31.1 (2008) ASME B31.3 (2008)

1. O nly str aigh t pipe calculations req uired if:

2. P ressu re sha ll be limited to 7 0 k Pa if :

or

and thi ckness is n ot l ess than requ ired for st raight pi pe

3. Press ure sh all be limited to 7 00 kPa if :

and

and thi ckness is n ot l ess than requ ired for st raight pi pe

4. For pressure ove r 700 kPa: pr oof t est, FEA, etc requir ed with a denedminimum for cl osely space d an d widely space d m iter bend

(t = T - c ):

and

2. When theta > 22 .5 d eg than m ax. al lowable p ressu re s hall calculated as ( t =T - c ):

For al l miter be nds t he R1 s hall not be less than:

with A:

(T-c) =< 13 mm A = 25

13 < ( T-c) =< 22 m m A = 2(T-c)

(T-c) > 22 m m A = 2(T-c)/3 + 30

are n ot perm itted. D eectionsconsidered as m iters.

2. I f 10% < h oop stress < 40exceed 12. 5 de g.

3. If hoop stress < 10 % SMY

4. If hoop stress > 10 % SMYless than on e pi pe d iameter

Reducer un der internal pressu re ( 104.6):

1. Fl anged reducer acco rding Table 1 26.1 a re c onsidered suitable a t thespecied pressure t emperature ratings.

2. W here bu tt welding redu cers are m ade t o a n ominal pipe thi ckness, thereducers sh all be considered suitable f or use with p ipe of t he same n ominalthickne ss.

Reducer u nder i nternal pressure (304.6.1(b)):

1. Re ducers acco rding Table 3 26.1 sha ll be considered suitable for use a testab lished p ressu re-temperature r atings or corr esponding str aight pi pe with87.5% of nom inal wa ll thickness.

2. Co ncentric reduce rs no t listed in Ta ble 3 26.1 m ay be designed accordingclosures a s pe r AS ME VIII div.1

Reducer under i nternal pr e

1. S teel butt we lded ttings sPractice a nd shall have presspipe of t he same o f equivalen

2. O ther pressure co ntainingphilosophy of t his co de subst

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ASME B31.1 (2008) ASME B31.3 (2008) ASME B31.8 (2007)

3. Co mponents no t covered by t he standards l isted in Ta ble 1 26.1 sha ll bebased on calcul ation consist ent with thi s co de. Calcul ations a re to besubstantiated b y o ne of:

- extens ive, succ ess ful service e xperience

- expe rimental ana lysis

- proo f t est

- detai led stress a nalysis, such as nite e lement analysi s

(Is A SME VIII div.1 U G32 acceptable?)

3. E ccentric redu cers n ot l isted in T able 3 26.1 a re qu alied as unlistedcomponents and shal l be d esigned and documented su bstantiated b y one of:

- extens ive, succ essful service e xperience


- proo f test

- detai led stress analysis, such a s n ite e lement ana lysis

(Is A SME VIII div.1 U G32 a cceptable?)

- ext ensive, succ ess ful servi ce e xperience


- proo f test

- en ginee ring calcul ations

3. Closu re hea ds s uch as at, ellipsoidal, spherical or conical heads are all owedfor use und er t his code . Such i tems m ay be d esigned in accordance with ASMEVIII div.1 (U G32).

Stubon under i nternal pressure (104.3.1(D)):

Required reinforcement ar ea is

= ang le betwee n branch and run

with A is a dditional t hickne ss for co rrosion andtolerances, t mh from straight pi pe calcul ation (104.1.2)

header exces s area, wi th

Stubon under i nternal pressu re ( 304.3.3):


= ang le betwee n branch and run

excess h eader, with

Stubon under i nternal pressure ( 831.4 an d ap p. F):

Required reinforcem ent area is ( Fig. F-5):

reinforcement by header

reinforcement by branch with

attached reinforcement, weld a rea and other ar ea

Assessment:

Area A2 and A3 to be multiplied by the ratio of al lowable w orking stress ,maximum multiplication factor i s1.0 (pa ra. 831.4(f ))

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branch excess

tr i s rei nforcem ent pad thi ckness

weld a rea

area reinf orcem ent ring

area sa ddle on right ang le co nnections

Assessm ent:

Area A2,A3, A4 and A5 to be multiplied by the ratio o f al lowable w orkingstress, m aximum multiplication factor i s 1 .0 (pa ra. 104 .3.1(D .2.3))

attached reinforcement, weld a rea and o ther ar ea

Assessm ent:

Area A2, A3 and A4 to be multiplied by the ratio o f al lowable w orking stress ,maximum multiplication factor i s 1 .0 (pa ra. 304.3.3(f3))

If then

assess

If then

assess

Tee (extruded outlet) under interna l pres sure ( 104.3.1(G)):


K = 1.0 when

K = when

K = 0.7 when

Tee (extrud ed outlet) under interna l pres sure ( 304.3.4):


K = 1.0 when

K = when

K = 0.7 when

Tee (extrud ed outlet) under interna l pres sure ( 831.4 r ef. App. F):


K = 1.0 when d/D > 0.60

K = 0.6+( 2d)/(3D) whe n 0.15 < d/D < = 0 .60

K = 0.7 when d/D

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excess branch area

Assessm ent:

reinforcement by h eader


excess branch area

Assessm ent:

If then asse ss

If then asses s


excess branch a rea

Assessment:

Weldolet (branc h) und er i nterna l pres sure ( 104.3.1(D)):


reinforcem ent by he ader, with


Weldolet (branch) under interna l pres sure (304.3.3):


reinforcem ent by h eader, with


Weldolet ( branch) und er i nternal pressure (831.4 ref . Ap p. F):

Required reinforcem ent area is ( Fig. F-5):



attached reinforcement, weld a rea and other ar ea

Assessment:

Area A2 and A3 to be multiplied by the ratio of al lowable w orking stress ,maximum multiplication factor i s 1 .0 (para. 831 .4(f))

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with

= thickness p ad or height of 60 deg angle tting with in r einforcementmaterial

= a rea provided by de posited weld m etal

exces s w eldolet area i n rei nforcement zon e

Assessm ent:

Area A2,A3, A4 and A5 to be multiplied by the ratio o f al lowable w orkingstress, m aximum multiplication factor i s 1 .0 (pa ra. 104 .3.1(D .2.3))

with

= thickness p ad or a h eight of 0

= area provi ded by de posited w eld metal and att ached rei nforcement

Assessm ent:

Area A2, A3 and A4 to be multiplied by the ratio o f al lowable w orking stress ,maximum multiplication factor i s 1 .0 (pa ra. 304.3.3(f3))

Cap under i nternal pressure (104.4.1(B)):

Can be calculated with ASME VIII div.1 U G-32 app.1-4

L = radius d ish

r = rad ius kn uckle

or

Cap under i nternal pressu re (304. 4.1(b)):


L = radius dish

r = rad ius k nuckle

or

Cap u nder internal pressu re ( 831.372 an d 831.373):


L = radius d ish

r = r adius k nuckle

or

Flat closu re un der interna l pres sure ( 104.4.1(b)):

Can b e cal culated with ASME VIII div.1 U G 34

Flat closu re un der interna l pres sure ( 304.4.1(b)):

Can be ca lculated with ASME VIII div.1 U G 34

Flat closu re und er i nterna l pres sure ( 831.373):

Can b e calc ulated w ith ASME VIII div.1 UG 34

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Flang e un der interna l pres sure (104.5.1(B)):

Can b e calcul ated a ccording ASME VIII div.1 ap p. 2 using B 31.3 al lowablestresse s an d tem perature l imits w ith:

= design ga uge pressure

= bolt desi gn stress at at mospheric tem perature

= bolt design s tress at design t emperature

= product SE

Flang e un der interna l pres sure ( 304.5.1(b)):

Can b e calcul ated a ccording ASME VIII div.1 ap p. 2 using B 31.3 al lowablestresses a nd tem perature l imits w ith:

= de sign g auge pressure

= bolt design stress at at mospheric t emperature

= bolt design stress at design tem peratur e

= product SEW

Flange under i nternal pr essure (831. 2):

Allowed to use:

ASME B16 seri es as l isted i n Appendix A such as B16.5.

Also MSS SP-44.

For slip-on w elding anges ref erence is m ade t o ASME VIII div.1 de sign.

Can ASME VIII div.1 be used for calculation?

Blind ange u nder i nternal pressure (104.5. 2(B)):

Can be calculated according ASME VIII div.1 U G-34 with:

= sum of allowances

= internal desi gn gauge pressure

= product SE

= p ressure desi gn thickness as pe r AS ME VIII div. 1 U G-34

Blind ange under i nternal pressure (304.5.2(b)):

Can be calculated according A SME VIII div.1 U G-34 w ith:

= sum of allowances

= int ernal desi gn gauge pressure

= product SEW

= p ressure desi gn thickness as p er AS ME VIII div. 1 U G-34

Blind ange u nder internal pressu re:

Can ASME VIII div.1 be used?

Blanks (spade) und er i nternal pressu re (304. 5.3(B)):

= sum of allowances

Blanks (spade) un der i nternal pressu re (304. 5.3(b)):

= sum of allowances

Blanks (spad e) under internal pressu re:

Can ASME VIII div.1 be used?

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= inside diameter of gasket = inside diameter of gasket

comparativo b31.1 _ b31.8

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