Ntawm Qhov Kev Sib Txuas Tshwj Xeeb ntawm Sodium Hydroxide Concentration thiab Sheath Surface Temperature Puas Yog 1.2 Millimeter 316 Stainless Steel Sheath Yuav Tsum Tau Hloov Txhua Rau Rau Lub Hlis hauv Aluminium Etching Bath Heater Service?

Cov txheej txheem engineers uas ua hauj lwm ntawm hluav taws xob immersion heaters nyob rau hauv txhuas etching da dej rau aerospace, automotive, thiab electronics industries feem ntau siv sodium hydroxide raws li etchant. Cov kev daws teeb meem etching yog 5-15% NaOH ntawm 60-80℃thiab yuav tshem tawm cov txhuas oxide thiab yaj cov hlau txhuas. Feem ntau, 1.2 hli 316 stainless hlau sheath yog siv los ua kom haum rau qhov chaw txwv ntawm etching tank thiab thermal teb xav tau. Txawm li cas los xij, lub siab caustic concentration, kub siab thiab dissolving khoom ntawm txhuas ua rau ib qho kev txhoj puab heev ib puag ncig. Ntawm cov theem pib, kev xeb dav dav tawm tsam 1.2 hli phab ntsa hauv rau lub hlis thiab yuav tsum tau hloov pauv ntawm ib nrab xyoo. Tsab xov xwm qhia meej txog qhov tseeb thiab qhov kub thiab txias ntawm 1.2 hli 316 sheath ua tiav nws txoj haujlwm rau lub hli.

Corrosion cwj pwm ntawm 316 nyob rau hauv sodium hydroxide uas muaj yaj txhuas
Thaum kub qis dua 60 degree, 316 stainless hlau tuaj yeem nyob twj ywm thiab muaj qhov corrosion tsawg dua 0.1 hli hauv ib xyoos hauv cov tshuaj sodium hydroxide saum 5%. Tab sis qhov siab dua qhov kub, qhov tsawg ruaj khov yog cov zaj duab xis passive. Lub etching tsim yaj aluminium uas accelerates corrosion los ntawm kev tsim aluminate ions uas tawm tsam cov zaj duab xis passive. Tus nqi corrosion tsis muaj txhuas yog 0.2-0.4 hli / xyoo ntawm 70oC hauv 10% NaOH. Tus nqi yog 0.5-1.0 hli ib xyoo nrog 10 g / L yaj aluminium. Nrog aluminium ntawm 80 degree, tus nqi yog 1.0-2.0 mm / xyoo. Rau ib tug 1.2 hli sheath yam tsawg kawg nkaus structural thickness rau siab ntim yog hais txog 0.5 hli. Corrosion nkag mus ntawm 0.7 hli hauv 6 lub hlis ntawm 1.4 hli / xyoo. Qhov kev hloov pauv rau lub hlis yog mus txog thaum kev sib xyaw ua ke ntawm caustic concentration, kub thiab txhuas cov ntsiab lus muab tus nqi corrosion ntawm 1.2-1.8 hli hauv ib xyoos.

Rau Lub Hlis Kev Pabcuam Lub Neej Tseem Ceeb
Kev ntsuam xyuas 316 hauv cov tshuaj sodium hydroxide nrog yaj txhuas cov yam ntxwv ntawm etching da dej kev pab qhia tau hais tias 1.2 hli phab ntsa muaj lub neej ua haujlwm siab tshaj plaws ntawm rau lub hlis rau kev sib xyaw ua ke ntawm caustic concentration thiab sheath nto kub.

Sodium Hydroxide Concentration (wt %) Dissolved Aluminium (g/L) Bulk Bath Temperature Sheath Surface Temperature at 6 W/cm2 (12℃rise) Cia Siab Corrosion Rate Lub Sijhawm Kom Txo 1.2 mm mus rau 0.5 mm Service Life 5% 5 70℃82℃0.70 mm2 – 10. 22 lub hlis 5% 10 70℃82℃0.6 - 1.0 mm / xyoo 0.7 - 1.2 xyoo 8 - 14 lub hlis 5% 15 70℃82℃0.8 - 1.3 mm / xyoo 0.5 - 0.9 xyoo 6 - 11 hli 8% 15 70℃0.8 – 1.4 xyoo 9 – 17 lub hlis 8% 10 65℃77℃0.8 – 1.3 mm/xyoo 0.5 – 0.9 xyoo 6 – 11 lub hlis 8% 15 65℃77℃1.0 – 1.6 mm/xyoo 0.5 – 0.8 hli
10% 5 60℃72℃0.6 - 1.0 mm/xyoo 0.7 - 1.2 xyoo 8 - 14 hli
10% 10 60℃72℃0.9 - 1.5 hli / xyoo 0.5 - 0.8 xyoo 6 - 9 hli
10% 15 60℃72℃1.2 - 1.9 mm / xyoo 0.4 - 0.6 xyoo 5 - 7 lub hlis
12%.
12% 15 55℃67℃1.4 - 2.2 mm / xyoo 0.3 - 0.5 xyoo 4 - 6 hli
15% 5 50℃62℃1.0 - 1.6 mm / xyoo 0.4 - 0.7 xyoo 5 - 8 lub hlis
15% 10 50℃62℃1.3 - 2.0 mm / xyoo 0.4 - 0.5 xyoo 4 - 6 lub hlis
15% 15 50℃62℃1.6 - 2.5 mm / xyoo 0.3 - 0.4 xyoo 3 - 5 lub hlis
Rau 10% NaOH txhuas etching da dej nrog 10 g / L yaj txhuas ntawm 60 degrees C tej qhov kub thiab txias nrog lub sheath ntawm 1.2 hli ntawm 6 W / cm2, lub sheath saum npoo kub yog hais txog 72 degrees C. Corrosion yog kwv yees mus ntxiv ntawm tus nqi ntawm 0.9 mus rau 1.5 mm ib xyoo, txo 5.5 hli rau phab ntsa. Kev hloov pauv rau - hli yog tsim nyog.

Lub hnab ntawv ua haujlwm nyab xeeb 6-hli hloov sijhawm
Kev hloov pauv yog tsim nyog kom ua tiav qhov kev pab cuam tsawg kawg ntawm rau lub hlis ua ntej phab ntsa raug txo mus rau 0.5 hli Qhov siab tshaj plaws kev nyab xeeb bulk sodium hydroxide kub rau 1.2 hli 316 sheath ntawm ntau yam watt ntom yog muab rau hauv cov lus hauv qab no. Tus nqi yog rau 10 g / L yaj aluminium, tus neeg sawv cev ntawm etching da dej.

Watt Density (Temp. Nce) Max Bulk Temp. 5% NaOH Max Bulk Temp. 8% NaOH Max Bulk Temp. 10% NaOH Max Bulk Temp. 12% NaOH Max Bulk Temp. 15% NaOH
4 W / cm² (8℃sawv) 74℃68℃62℃57℃52℃6 W / cm² (12℃sawv) 70℃64℃58℃53℃48℃8 W / cm² (16℃sawv) 66℃60℃54℃49℃204℃56℃50℃45℃40 degree
Rau ib qho txhuas etching da dej, 10% NaOH, bulk kub 60C, 6 W / cm^2 (12C nce, 72C nto), kev nyab xeeb bulk txwv yog 58C. Lub rhaub rau 60℃tshaj qhov kev nyab xeeb txwv, thiab kev pabcuam lub neej ntawm rau lub hlis tsis tuaj yeem lav. Txo qhov ceev ntawm watt mus rau 4 W / cm2 (8℃nce, 68℃nto) yields ib qho kev txwv tsis pub dhau 62℃yog li 60℃yog tsim rau rau -hli hloov.

Tsim Cov Kev Hloov Kho kom ntev lub neej ntev dua 6 lub hlis
Aluminium etching tej zaum yuav xav tau 1.2 hli 316 sheath thiab rau lub hlis lub neej tsis txaus. Peb qhov kev hloov kho tuaj yeem ua rau lub neej ua haujlwm ntev. Thawj yog siv lub tshuab rhaub kom ntev dua kom txo qis watt ceev. Txo los ntawm 6 W / cm² mus rau 4 W / cm² mus los ntawm 6 lub hlis tsoom fwv mus rau 8 - 12 lub hlis tsoom fwv, qhov kub ntawm qhov chaw nce los ntawm 12℃mus rau 8℃. Qhov kev hloov pauv thib ob yog kev tswj hwm ntawm cov concentration ntawm yaj aluminium los ntawm da dej pom lossis hloov ib nrab. Txo cov txhuas los ntawm 15 g / L mus rau 5 g / L tuaj yeem txo qis corrosion ntawm 30-50%. Ib qho kev hloov pauv thib peb suav nrog kev siv cov nickel-based alloy xws li Alloy 600 lossis Alloy 825. Hauv 10-15% NaOH ntawm 70℃nrog yaj aluminium cov ntaub ntawv no muaj cov nqi corrosion.<0.1 mm/year, increasing the service life to 5–10 years. For long-term use, engineers should specify Alloy 825 for continuous-use aluminium etching baths using 10% NaOH at 65°C. When specifying the heaters for etching bath service, always provide the correct NaOH concentration, bulk temperature, dissolved aluminium level and the intended replacement interval. The six month replacement threshold for a 1.2 mm 316 sheath is a predictable function of these characteristics therefore allowing precise prediction of heater life in aluminium etching procedures.