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ABB GroupFebruary 18, 2014 | Slide 2

"!roducio!

ASME PTC 19.3 TW-2010 was written to replace ASME PTC

19.3-1974 followin so!e catastrop"ic fail#res in non-stea!ser$ice% t"ese t"er!owells passe& t"e criteria lai& o#t in1974.

T"e 2010 stan&ar& incl#&es sinificant a&$ances in t"e'nowle&e of t"er!owell (e"a$io#r. ASME PTC TW-2010e$al#ates t"er!owell s#ita(ilit) new an& i!pro$e&calc#lations incl#&in*

+ario#s t"er!owell &esins incl#&in steppe& t"er!owells

T"er!owell !aterial properties

,etaile& process infor!ation

e$iew of t"e accepta(le li!it for fre#enc) ratio

Stea&)-state% &)na!ic an& press#re stress

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ABB GroupFebruary 18, 2014 | Slide 4

Sre--e- o! a Thermowell

T"er!owells protect te!perat#re sensors fro! &irectcontact wit" a process fl#i&. /#t once inserte& into t"eprocess% t"e t"er!owell can o(str#ct flow aro#n& it%lea&in to a &rop in press#re. T"is p"eno!enon creates

low press#re $ortices &ownstrea! of t"e t"er!owell.

T"ese $ortices occ#r at one si&e oft"e t"er!owell an& t"en t"e ot"er%w"ic" is 'nown as alternatin $orte

s"e&&in. T"is effect can (e seen int"e ea!ple of a fla pole ripplin afla in t"e win&

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ABB GroupFebruary 18, 2014 | Slide

Freue!cy 3aio

+orte s"e&&in ca#ses t"e

t"er!owell to $i(rate.f t"is $orte s"e&&in rate

fs !atc"es t"e nat#ral

fre#enc) fn

c of t"e

t"er!owell% resonance

occ#rs% an& &)na!ic(en&in stress on t"et"er!owell reatl)increases

T"e $orte s"e&&in rate for t"e &ra an& lift !#st (e calc#late&. T"ein-line fre#enc) parallel to flow is 2 t"e trans$erse fre#enc).

5orces create& () t"e fl#i& in t"e 6 plane in-line wit" flow are

calle& &ra an& forces create& in t"e plane trans$erse to floware calle& lift

5

Flow 6irecio!

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"!duced Freue!cie-

)here he i!duced +reue!cy mee- he !aural +reue!cy o+ he hermowell he ampliude

o+ 7ibraio! i!crea-e- rapidly

The dra +reue!cy i!duced i- wice ha o+ he li+ +reue!cy i!duced'

A- -uch i mee- he !aural +reue!cy o+ he hermowell a hal+ he +luid 7elociy o+ he li+

i!duced +reue!cy

The dra +orce- are -maller ha! he li+ +orce- a!d u!der cerai! -pecial co!diio!- may !o

be -i!i+ica!'

ABB GroupFebruary 18, 2014 | Slide

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3e-o!a!ce 9loc: i!;

Boh li+ a!d dra re-o!a!ce e!d- o 9loc: i!; o! he

!aural +reue!cy

The low dampi! o+ hermowell- e

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Freue!cy 3aio @imi

T"e fre#enc) ratio fs8 fnc is t"e ratio (etween t"e $orte

s"e&&in rate an& t"e installe& nat#ral fre#enc). n t"e ol&stan&ar&% t"e fre#enc) ratio li!it was set to 0.. T"is was toa$oi& t"e critical resonance ca#se& () t"e trans$erse lift forces

T"e trans$erse

resonance (an&is a(o$e t"e 0.li!it

5ollowin t"e incl#sion of

t"e in-line &ra forces% asecon& resonance (an&!a) also nee& to (ea$oi&e&

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Freue!cy 3aio @imi

T"e fre#enc) li!itratio is set at eit"er0.4 or 0.. T"ecriteria for w"ic"li!it to #se is&efine& in ASME

PTC 19.3 TW-2010an& t"e t"eor) issi!plifie& (elow.T"is is t"e t"eor)#se& in t"e

calc#lation an&s"o#l& not (eesti!ate& wit"o#tcarr)in o#t t"e f#lle$al#ation.

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Thermowell- whe! o per+orm a calculaio!

A hermowell ca! be co!-idered o

be a !eliible ri-: i+ he +ollowi!

crieria are me

%roce-- +luid 7elociy i- le--

ha! 0'4 m-

)all hic:!e-- i- &' mm or

more

D!-uppored le!h i- 10 mmor le--

3oo a!d ip diameer are 12'

mm or more

#a

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Thermowell- A--umpio!- a!d limi-

A !umber o+ a--umpio!- are made i! he

-a!dard

Sur+ace +i!i-h o+ he hermowell will

be (2 3a or beer

The hermowell i- -olid drilled

There i- !o weldi! o! he -em o+ he

hermowell >oher ha! he aachme!

o he +la!e?

Tha he +la!e rai! a!d aachme!

are i! complia!ce wih e-abli-hed

-a!dard- '

Tha he hermowell i- wihi! he

dime!-io! limi- i7e! i! he -a!dard>able 4*1*1 a!d 4*2*1?

Tha a!y corro-io! or ero-io! i-

allowed +or

ABB GroupFebruary 18, 2014 | Slide 12

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Thermowell he pa-- crieria

There are +our crieria +or a

hermowell o pa-- e7aluaio! o

%TC 1&'( T)*2010

Frequency limit: he re-o!a!ce

+reue!cy o+ he hermowell -hall

be -u++icie!ly hih -o ha

de-ruci7e o-cillaio!- are !o

e

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ABB GroupFebruary 18, 2014 | Slide 14

"!roducio! o ABB- )a:e Freue!cyCalculaio!

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ABB GroupFebruary 18, 2014 | Slide 1

Thermowell Type-

ST3T3$A6 ST3S) ST3F@G ST3EA= ST3)$@6

TA%T3$A6 TA%S) TA%F@G TA%EA= TA%)$@6

ST$%T3$A6 ST$%S) ST$%F@G ST$%EA= ST$%)$@6

H$5 ST3 I ST3A"GT TA% I TA%$3$6 ST$% I ST$%%$6

T3$A6 I T3$A6$6 S) I SJCH$T )$@6 F@G I F@A=G$6

EA= I EA= STJ=$ )$@6 I )$@6*"=

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ABB GroupFebruary 18, 2014 | Slide 1

6ime!-io! 6eail-

=oe

@-a!d b-are o!ly applicable +or -ep*-ha!: hermowell-

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ABB GroupFebruary 18, 2014 | Slide 18

)he! a Calculaio! Fail-

f a t"er!owell fails t"e e$al#ation% t"e &esin can (e

c"ane& in t"e followin wa)s*K S"orten t"e t"er!owell to rece t"e #ns#pporte& lent"

K ncrease t"e t"ic'ness of t"e t"er!owell A an& /

A $elocit) collar can (e a&&e& to rece t"e #ns#pporte&lent" alt"o#" t"is is not enerall) reco!!en&e&. A$elocit) collar is #se& to pro$i&e a rii& s#pport to t"et"er!owell an& will wor' onl) if t"ere is an interference fit(etween t"e stan&off wall an& t"e collar.

Care !#st (e ta'en to ens#re t"e collar !eets t"e stan&offwall at installation an& is not affecte& () corrosion. f a$elocit) collar is t"e onl) $ia(le sol#tion% it is t"eresponsi(ilit) of t"e operator to ens#re t"ere is aninterference fit (etween t"e stan&off wall an& t"e $elocit)

collar.

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ABB GroupFebruary 18, 2014 | Slide 1&