Ntawm qhov tshwj xeeb kev sib xyaw ua ke ntawm Thermal Cycle Frequency thiab Temperature Delta Puas Yog 2.5 millimeter 316 Stainless Steel Sheath Experience Plastic Ratcheting Failure Ua ntej 1.2 millimeter Sheath hauv Jacketed Reactor Heating Service?

Cov kev qaug zog raug tsim los ntawm cov txheej txheem thermal cycling ntawm batch chemical processing yog tshwj xeeb rau cov txheej txheem engineers uas tsim cov hluav taws xob tso cua sov rau cov tsho reactors thiab autoclaves thiab tsis tshua muaj kev paub txog kev pabcuam txuas ntxiv. Lub reactor tuaj yeem voj voog ntawm 20℃mus rau 200℃thiab rov qab ntau zaus hauv ib hnub, cov cua kub uas txwv los ntawm cov kev xav tau ntawm cov tshuaj tiv thaiv. Phab ntsa tuab ntawm 316 stainless hlau sheath hauv paus hloov qhov kev ntxhov siab - strain teb rau cov voj voog no. Tab sis nyob rau hauv ib tug counter-intuitive txoj kev, ib tug tuab 2.5 hli phab ntsa tuaj yeem ua tsis tiav los ntawm cov yas ratcheting - maj mam tsim ntawm strain nyob rau hauv ib qho kev taw qhia nrog txhua lub voj voog - whereas ib tug nyias 1.2 hli phab ntsa yuav nyob elastic thiab nyob indefinitely. Kab lus no txiav txim siab qhov sib xyaw ua ke ntawm thermal voj voog zaus thiab qhov kub thiab txias delta ntawm 2.5 hli 316 sheath yuav ua tsis tiav ua ntej 1.2 hli sheath nyob rau hauv jacketed reactor cua sov kev pab cuam.

Yas ratchet mechanism nyob rau hauv tuab -walled sheaths
Yas ratcheting yog txhais raws li qhov deformation ntawm ib feem ntawm lub voj voog thermal kev nyuab siab uas tshaj cov khoom yield zog nyob rau hauv ib qho kev taw qhia tab sis tsis nyob rau hauv lwm txoj kev. Thaum tshav kub kub sai, sab nraud ntawm qhov tuab -walled 316 sheath nthuav ntau dua li sab hauv qhov chaw xws li sab nrauv yog compression thiab sab hauv qhov nro. Yog tias qhov kev ntxhov siab no ntau dua li cov khoom siv, cov khoom deforms plastically. Raws li nws cools lub sab nrauv shrinks sai dua. Txoj kev ntxhov siab thim rov qab. Yog tias qhov txias txias tsis siab tshaj qhov tawm los, cov khoom siv tsis zoo tag nrho rau nws lub xeev dhau los. Txhua lub voj voog cua sov sib sau ua ke me me ntawm cov tensile strain nyob rau sab hauv. Qhov kev sib tw ratcheting no tuaj yeem ncav cuag 5-10% tom qab ntau txhiab lub voj voog ua kom tsis muaj zog thiab qhov tshwm sim tawg. Rau cov phab ntsa thickness ntawm 1.2 hli, qhov kub ntawm cov gradient los ntawm phab ntsa yog tsawg dua, yog li cov thermal stress tseem nyob hauv qab yield rau ob qho tib si cua sov thiab txias, yog li tsis muaj ratcheting. Cov metric tseem ceeb yog tus lej Biot - qhov piv ntawm cov khoom siv hluav taws xob sab hauv rau sab nrauv convective kuj. Biot tus lej yog dhau ntawm qhov pib ntawm ratcheting rau cov phab ntsa tuab hauv cov nruab nrab convection tsawg xws li cov kua reactor viscous.

Kev txwv ntau ntawm ratcheting puas
Cov kev txwv no tau muab los ntawm kev tshawb fawb txog 316 sheaths nyob rau hauv cov kev pab cuam lub tsho reactor nrog ntuj convection tshav kub kis (coefficient ntawm 200 W / m2·K). Ratcheting tshwm sim thaum qhov kub thiab txias delta txhua lub voj voog yog siab dua 120℃thiab qhov cua kub siab tshaj 5℃ib feeb rau phab ntsa 2.5 hli. Ntawm delta ntawm 150℃thiab cua sov ntawm 10℃/ min, ratcheting strain txhua lub voj voog yog nyob ib ncig ntawm 0.02%. Tom qab 10000 cycles tsub zuj zuj tag nrho strain ntau tshaj 2% thiab pom cov phab ntsa tsis muaj zog yog pom. Tom qab 25,000 cycles, strain yog 5% nrog pom tseeb tawg. Rau 1.2 hli phab ntsa, qhov siab tshaj plaws thermal stress tsuas yog 120 MPa nyob rau hauv tib yam mob, ntau hauv qab 200 MPa yield zog ntawm 316 ntawm 150 degree, yog li tsis muaj ratcheting. 1.2 hli phab ntsa pib ratchet ntawm delta kub siab tshaj 180 degree, tab sis lub 2.5 hli phab ntsa tsis nyob rau hauv ib tug delta ntawm 130 degree. Yog li qhov tsim nyog delta rau inversion ratcheting yog 120-140 degree. Hauv qab qhov ntau yam tsis muaj phab ntsa muaj ratchets. Cov ratchets rau 2.5 hli phab ntsa saum toj no ntau thiab cov phab ntsa 1.2 hli yog elastic mus rau ib tug loj delta.

Qhov tseem ceeb Ratcheting Thresholds rau 316 Sheath Phab ntsa Thickness
Cov lus hauv qab no qhia txog kev sib txuas ntawm qhov tseem ceeb ntawm qhov kub thiab txias, delta, thiab cua sov tus nqi ntawm cov yas ratcheting pib rau ntau yam 316 sheath phab ntsa thicknesses nyob rau hauv jacketed reactor kev pab cuam. Qhov tseem ceeb yog rau tej yam ntuj tso convection nyob rau hauv ib tug viscous kua (200 W / m2 K) thiab siab tshaj plaws khiav hauj lwm kub ntawm 200 degree.

Sheath Phab ntsa Thickness Yam tsawg kawg nkaus kub qhov sib txawv rau kev pib ntawm Ratcheting Yam tsawg kawg nkaus cua sov rau Ratcheting ntawm 150℃DeltaRatchet Strain ib lub voj voog ntawm 150℃Delta, 10℃/ minCycles mus rau 2% Strain AccumulationCycles rau Failure (5% Strain)
0.8 - 1.0 hli saum 180℃Saum 20℃/ min Tsis muaj qis dua 180℃Tsis siv tau Tsis muaj
1.2 - 1.4 mm Saum 170℃Saum 15℃/ min Tsis muaj qis dua 170℃Tsis muaj Tsis muaj 1.6 - 1.8 mm 150 - 160℃12 - 15℃/min 0.005 - 0.010% 20,000 - 60}8,0{ 2.2 hli 130 - 140℃8 - 10℃/ min 0.015 - 0.025% 8,000 - 13, 000 20,000 - 30, 000 2.5 - 2.8 mm 120 - 130℃5 - 8℃305% -0.5, 10,{44},000 – 25,000
Rau batch reactor uas mus ntawm 20 C mus rau 200 C (delta ntawm 180 C) ob zaug ib hnub twg. Tus naj npawb ntawm cov voj voog ib xyoos yog kwv yees li 730 cycles. Ntawm no delta, 2.5 hli sheath yuav tsim 0.025-0.035% strain ib lub voj voog, uas yuav nce mus rau 2% strain tom qab 5,000-8,000 cycles, los yog 7-11 xyoo. Lub 1.2 hli sheath yuav tsis ratchet, thiab tsuas yog tawg los ntawm lwm txoj kev xws li corrosion los yog kev co qaug zog. Rau cov reactors nrog cov cua kub ceev, piv txwv li, cov roj kub ncig lossis chav, qhov pib ratcheting tshwm sim ntawm cov deltas me. Yog tias koj rhaub lub reactor ntawm 50℃mus rau 200℃ntawm 20℃/ min, koj yuav tau txais ib tug delta ntawm 150 degree, tab sis ib tug heev thermal gradient. Raws li cov kev teeb tsa no, 2.5 hli sheath tuaj yeem ua tsis tiav tom qab tsawg li 2000 lub voj voog (3 xyoos ntawm 2 lub voj voog txhua hnub), thaum 1.2 hli sheath muaj kev nyab xeeb.

Tsim Kev Hloov Kom Tiv Thaiv Ratcheting
Peb qhov kev tsim kho tuaj yeem tiv thaiv cov yas ratcheting hauv tuab -walled 316 sheath xav tau rau kev tiv thaiv siab lossis kev tiv thaiv corrosion hauv kev pabcuam cyclic reactor. Thawj yog txwv tsis pub tus nqi cua sov. Txo tus nqi nce ntawm 10C / min mus rau 3C / min txo cov thermal gradient los ntawm ~ 60% thiab ua rau muaj kev ntxhov siab hauv qab cov txiaj ntsig txawm tias muaj phab ntsa 2.5 hli. Qhov thib ob hloov yog tias es tsis txhob txias lub reactor mus rau ambient kub, nws yog preheated rau qhov tsawg kawg nkaus standby kub ntawm 80 degree. Ratcheting yog tshem tawm tag nrho nrog txo cov delta ntawm 180℃mus rau 100℃yam tsis muaj kev hwm rau phab ntsa thickness. Qhov kev hloov thib peb yog xaiv cov khoom siv nrog txo thermal expansion thiab ntau dua yield zog ntawm qhov kub thiab txias. Piv txwv li, thermal expansion coefficient ntawm 316 yog 17 × 10 -6 /℃vs 14 × 10 -6 /℃rau Incoloy 800H. Incoloy 800H kuj tseem khaws lub zog zoo ntawm 200 degree. Qhov kev sib xyaw ua ke no txo ​​cov thermal stress ntawm li 25% rau tib lub delta thiab phab ntsa thickness. Rau feem ntau batch reactor daim ntawv thov phab ntsa thickness ntawm 1.2-1.6 hli yuav muab cov neeg kho tshuab txaus tsis muaj ratcheting. Cov kws kho tsheb uas dig muag thov cov phab ntsa tuab rau "durability" hauv kev pabcuam cyclic tuaj yeem xaiv qhov system uas ua tsis tau ntxov ntxov los ntawm ratcheting. Txoj hauv kev kom raug yog ua haujlwm tawm ntawm lub voj voog delta, thiab cua sov tus nqi, thiab tom qab ntawd xaiv cov phab ntsa thinnest uas ua tau raws li qhov xav tau ntawm qhov siab thiab corrosion. Yog tias tsis ntseeg, nug tus kws tsim lub tshuab rhaub rau kev kawm ratcheting siv cov qauv tsim qauv ntawm lub voj voog caij nyoog. Ib tus neeg muag khoom uas tsis muab txoj kev tshawb fawb no yuav tsis nkag siab txog cov txheej txheem tsis ua haujlwm ntawm cov phab ntsa tuab hauv kev siv cyclic thermal.