Conas a chinneadh an sáraíonn an tiúchan aigéad san umar picilte tumoideachais an caighdeán?

To determine whether the acid concentration of the immersion pickling tank exceeds the standard, a comprehensive analysis needs to be conducted in combination with the process standards, detection methods and actual reaction phenomena. The following are specific methods: 1. Concentration threshold based on process standards Each pickling process (such as steel rust removal, metal surface activation, etc.) has a clear acid concentration range, and the process documents or formula requirements need to be confirmed in advance. For example: Hydrochloric acid pickling: The commonly used concentration in the steel industry is 10%~20% (mass fraction). If the measured concentration is greater than 25% or less than 8%, it is considered to exceed the standard. Sulfuric acid pickling: The concentration is usually controlled at 15%~25%. Exceeding 30% may accelerate metal corrosion and produce a large amount of hydrogen. If it is less than 10%, the rust removal efficiency will be significantly reduced. Mixed acid (such as hydrochloric acid + hydrofluoric acid): It needs to be controlled according to a specific ratio (such as HCl:HNO₃=3:1). If the concentration of a single acid deviates from the formula by ±10%, it will be judged as abnormal. 2. Laboratory test method (precise quantification) The most reliable way to judge is to analyze the concentration of acid by sampling: Titration method (chemical analysis) Principle: Titrate the acid with a standard alkali solution (such as NaOH) and calculate the acid concentration by the amount of alkali consumed. Operation steps: Accurately draw 10mL of acid with a pipette, inject it into a conical flask, and add 2~3 drops of phenolphthalein indicator. Titrate with a known concentration of NaOH standard solution (such as 0.1mol/L) until the solution is slightly red and does not fade for 30 seconds, and record the consumed volume V (mL). Judgment standard: If the calculated result exceeds the process allowable range (such as ±5% fluctuation), it is considered that the concentration exceeds the standard. Density method (applicable to strong acid) Principle: The concentration of acid is linearly related to density (such as the higher the concentration of concentrated sulfuric acid, the greater the density), and the density is measured by looking up the table for comparison. Operation steps: Use a densitometer (or hydrometer) to directly immerse in the acid, read the scale value, and measure the temperature at the same time (need to be calibrated to the standard temperature of 20℃). Refer to the "Acid Concentration - Density Comparison Table" (e.g., hydrochloric acid at 20°C, 20% concentration corresponds to a density of about 1.09g/mL). If the measured value deviates from ±0.02g/mL, the concentration may be abnormal. pH detection method (applicable to dilute acid or mixed acid) principle: acid concentration is negatively correlated with pH value (the higher the concentration, the lower the pH), but it should be noted that strong acids (such as hydrochloric acid and sulfuric acid) have a dissociation℃close to 100% at high concentrations, and may not be sensitive to pH changes (e.g., 20% hydrochloric acid pH≈-0.3, 15% hydrochloric acid pH≈-0.1), and need to be used in combination with titration. The pH of weak acids (such as hydrofluoric acid) is nonlinearly related to concentration and needs to be converted through a standard curve. 3. On-site rapid detection method (convenient qualitative) is suitable for real-time monitoring or scenarios without laboratory conditions: pH test paper/test strips Use a glass rod to dip acid and drop it on the test paper, compare the pH value with the standard color card, and combine process experience to determine whether the concentration is abnormal (for example, in steel pickling, hydrochloric acid pH>1 may be insufficient). Acid concentration test paper (special test paper) Some manufacturers provide test paper for specific acids (such as hydrochloric acid concentration test paper), which will develop color after being immersed in acid, directly corresponding to the concentration range (such as 10%~15%, 15%~20%, etc.). Conductivity method (portable conductivity meter is airde an tiúchan aigéad, is ea is mó an tiúchan ian agus an níos airde an seoltacht {. Déantar an cuar “comhchruinnithe” réamh-chalabraithe, agus nuair a dhiúltaíonn an luach tomhaiste ón gcuar faoi ± 10%, léiríonn sé go bhfuil an tiúchan neamhghnách {{}}} an t-imoibriú idir an t-imoibriú, an t-imoibriú a bhreathnaíonn an t-imoibriú idir an t-imoibriú agus an t-imoibriú a bhreathnaíonn an t-imoibriú idir an t-imoibriú agus an t-imoibriú go bhfuil an t-imoibriú an fíoradh idir an t-imoibriú is ea an t-imoibriú go bhfuil an t-imoibriú} { Athróidh an t -aigéad go suntasach, ar féidir é a úsáid mar réamhbhonn le haghaidh breithiúnais: tiúchan neamhleor (íseal) feiniméan: an ráta giniúna mboilgeog ar dhromchla na hoibre (imoibríonn an miotail leis an aigéad chun níos lú hidrigine Ní theipeann ar phicil a cuireadh i gcrích ar dtús i 30 nóiméad an caighdeán a chomhlíonadh tar éis níos mó ná 1 uair an chloig) . Níl an t -athrú datha ar an tuaslagán aigéad soiléir (E . g ., i bpicil na cruach, méadaíonn an tiúchan Fex go mall, agus ní chasann an tuaslagán aigéad glas mar a bhfuiltear ag súil leis. . abnormal weight loss appear (increased risk of hydrogen embrittlement). The temperature of the acid solution rises abnormally (if the operation is improper when diluting concentrated sulfuric acid, it may boil due to intense heat release). V. Frequency and record requirements Inspection frequency: In regular production, 1~2 times per shift (8 uaireanta) . Má tá cobhsaíocht an phróisis lag nó leanúnach, is gá iniúchadh a dhéanamh uair amháin gach 2 uair an chloig {. tar éis tuaslagán aigéad nua a ullmhú, tuaslagán aigéad a chur leis, nó an t -ábhar oibre a athrú, ní mór an tiúchan a thástáil láithreach . taifead a dhéanamh, an tiúchan a bhrath, an tiúchan a bhrath, tiúchan a bhrath, tiúchan a thaifeadadh agus an tiúchan a bhunú, tiúchan a thaifeadadh, tiúchan a thaifeadadh agus luach a fháil ar luach an luach a thaifeadadh an luach a bheith aige luach a thaifeadadh} {{{{} {}} \\ t níos mó ná an caighdeán {. I gcás neamhghnácha, ní mór na bearta cóireála (mar shampla aigéad a chur leis, caolú nó athsholáthar) a mharcáil . 6. Réamhchúraimí Oibriú Sábháilte: Caith lámhainní aigéad-cruthúnas agus cosanta le linn tástála chun splancscáileán aigéad a sheachaint; Doirt an sampla aigéad go mall chun splancscáileán a chosc {. Tionchar teochta: Agus dlús nó seoltacht á thástáil, ní mór an teocht aigéid a cheartú go dtí an teocht chaighdeánach (mar shampla 20 céim), ar shlí eile beidh sé ina chúis le hearráidí (méaduithe teochta agus dlús leachtach laghduithe ar an aigéad, má tá an t -aigéad i bhfeidhm), má tá an t -aigéad i bhfeidhm (FEUS FESAL UAS IONTEACH+FEUS FEUS+FE FE+FESTES fachtóirí a bhfuil fachtóirí iontu fachtóirí a bhfuil fachtóirí iontu fachtóirí a bheith ann nó seoltacht, agus ní mór an modh toirtmheasctha a chomhcheangal chun na torthaí a cheartú {. trí bhreithiúnas cuimsitheach na modhanna thuas, is féidir an tiúchan aigéad neamhghnách a aimsiú in am chun éifeachtaí picilte neamhcháilithe a sheachaint mar gheall ar chomhchruinniú neamhleor, nó timpistí sábháilteachta {46} de bharr tiúchan iomarcach (amhail creimeadh iomarcach, sainiú hidrigine).}}}}}}}}}}}}}}}}}}}} (