Thermocouples muaj lub neej ua haujlwm ntev. Kev txheeb xyuas cov cim kev laus thaum ntxov thiab tsim lub sijhawm hloov pauv yog cov kev ntsuas zoo kom tsis txhob ua tsis tiav tam sim ntawd. Kab lus no muab cov qauv tsim nyog rau kev lees paub thaum hloov pauv yog qhov tsim nyog.
Key Aging Indicators. Kev laus manifests los ntawm: nruam tso zis drift- qhov tshwm sim kub maj deviates los ntawm setpoint txawm tus txheej txheem ruaj khov; nce teeb liab suab nrov-random kub dhia ntawm 1-3℃; qeeb teb- lub sensor yuav siv sij hawm ntev dua kom ncav cuag qhov kub thiab txias tom qab hloov chaw; thiab kev hloov ntawm lub cev-kev hloov pauv ntawm lub cev, oxidation, lossis deformation.
Drift ua lub cim tseem ceeb. Tsis tu ncua calibration qhia drift. Yog hais tias drift yog trending mus rau lub sensor lub kam rau siab txwv (feem ntau ± 2℃rau Class 1), npaj hloov. Nyob rau hauv ib rooj plaub, thermocouple drift ua rau 8.5℃qhov kub tsis sib xws ntawm qhov kawg nozzles, txo cov txiaj ntsig ntawm 99.3% mus rau 94%. Qhov no qhia txog kev cuam tshuam txog kev lag luam ntawm kev tsis quav ntsej kev poob siab.
Visual Inspection Indicators. Thaum lub sij hawm niaj hnub tu, tshuaj xyuas rau: tsaus nti (oxidation), pitting (tshuaj lom neeg tua), flattening los yog qhab nia (kev puas tsuaj), thiab txhua yam deformation ntawm lub sheath. Ib qho kev puas tsuaj pom tau hloov pauv, txawm tias lub sensor tseem nyeem kom raug.
Resistance and Insulation Checks. A gradual increase in loop resistance (e.g., from 5 Ω to >15 Ω) qhia oxidation sab hauv. Rwb thaiv tsev tiv thaiv qis dua 10 MΩ ntawm chav tsev kub qhia tias ya raws lossis rwb thaiv tsev tawg. Ob qho xwm txheej pom zoo hloov tam sim ntawd.
Establishing Replacement Intervals. Based on application and historical performance, set maximum service life limits. For high-temperature zones (>350 degree), hloov txhua 6-8 lub hlis. Rau cov cheeb tsam txheem, 12-14 lub hlis yog qhov raug. Hloov kev ua haujlwm raws li kev pabcuam lub neej, tsis txhob tos kom tsis ua haujlwm.
Case Study: PET Preform Moulding. Hauv PET preform ntau lawm, thermocouple aging ua rau incremental yield deterioration. Los ntawm kev tsim lub 8-lub hlis hloov lub sij hawm, lub preform molder txo cov seem seem los ntawm 30% thiab txhim kho kev ruaj ntseg ntau lawm.
Cov ntaub ntawv Logging txhawb kev kwv yees. Siv cov ntaub ntawv tswj xyuas cov ntaub ntawv txhawm rau taug qab qhov ntsuas kub ntawm lub sijhawm. Predictive algorithms tuaj yeem txheeb xyuas thaum tus nqi nrawm nrawm, taw qhia qhov kawg - ntawm - lub neej. Qhov no ua rau lub sijhawm hloov pauv tsis yog kev teb thaum muaj xwm txheej ceev, txo cov nqi poob qis txog li 80%.
