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    피볡아크 및 ν”ŒλŸ­μŠ€ μ½”μ–΄λ“œ 아크 μš©μ ‘μ—μ„œ λ°œμƒν•˜λŠ” 흄 및 6κ°€ 크둬 λ°œμƒ 저감을 μœ„ν•œ μš©κ°€μž¬ μ„±λΆ„ 연ꡬ

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    ν•™μœ„λ…Όλ¬Έ(석사) -- μ„œμšΈλŒ€ν•™κ΅λŒ€ν•™μ› : λ³΄κ±΄λŒ€ν•™μ› ν™˜κ²½λ³΄κ±΄ν•™κ³Ό, 2022. 8. μœ€μΆ©μ‹.Welding generates welding fumes and hexavalent chromium, which are classified as Group 1 carcinogens by the International Agency for Research on Cancer (IARC). In particular, due to the generation of high hexavalent chromium and fumes in shielded metal arc welding (SMAW) and flux-cored arc welding (FCAW), they impose a severe health risk upon exposure. Thus, this study aims to estimate the welding filler material components that can reduce the generation of fumes and hexavalent chromium in SMAW and FCAW. In the current study, nine welding rods for SMAW and eight flux-cored wires for FCAW were tested. Each type of welding was performed under uniform conditions in a fume-hood. Collected fume samples were analyzed by gravimetric analysis to calculate fume generation rate (FGR) and ion chromatography with the ultraviolet detection (IC-UV) for hexavalent chromium generation rate (HCGR). Welding filler materials were analyzed using wavelength dispersive X-ray fluorescence spectrometer (WDXRF). After performing statistical difference tests, a correlation analysis was conducted to estimate the statistical association between the generation rate and the content of filler component in the welding material in each type of welding. Based on the results of the correlation analysis, regression models were designed and then analyzed through multiple linear regression method. Finally, based on the results of correlation and multiple linear regression analyses, the component-combination formulas were designed and correlation analysis was conducted with fume generation rate and hexavalent chromium generation rate. For nine SMAW welding rods, FGR(per welding time) was in the range of 198.0–289.3 mg/min, and HCGR(per welding time) was in the range of 5.34–7.98 mg/min. By changing the welding filler material components under the same welding conditions, the generation rate was found to be reduced by approximately 26.7% (AVG = 20%) and 24.8% (AVG = 3.4%) compared to base FGR and HCGR, respectively. In the case of eight flux-cored wires, FGR was 590.4–821.1 and HCGR was 0.34–3.31 mg/min, which could be reduced by up to 23.5% (AVG = 10%) and 89.7% (AVG = 47.1%), respectively, by changing the welding material components under the same welding conditions. The results of correlation analysis of SMAW, with different elements as filler material, suggested a statistically significant correlation of fluorine (F), potassium (K), calcium (Ca), and sodium (Na) with FGR and chromium (Cr) and titanium (Ti) with HCGR. Whereas, in the case of FCAW, fluorine (F), potassium (K), and sodium (Na) with FGR and sodium (Na), potassium (K), silicon (Si), zirconium (Zr), and fluorine (F) with HCGR showed a statistically significant correlation. In most multiple linear regression models, the multicollinearity problem arises due to the interference among independent variables. That is, some specific elements did not strongly contribute to the change in the value of the dependent variable, and several elements made complex contributions in the fume and hexavalent chromium generation rate. So, this study proposed eleven component-combination formulas showing statistically significant correlation with dependent variables for SMAW and ten for FCAW. This study suggests that it is possible to reduce FGR and HCGR without affecting the performance of welding by using different components as welding materials. In order to reduce HCGR, it is recommended to reduce the FGR for SMAW and to reduce the content of hexavalent chromium in welding fumes for FCAW. Also, it is recommended to manufacture welding materials with components that can suppress oxidation of chromium and have higher electronegativity than metal chromium and chromium compounds. Thus, by considering the oxidation ability and electronegativity of the compound, HCGR can be reduced. If welding materials with low FGR and HCGR are manufactured and widely used in the field as per the suggested change in element content presented in this study, the problem of exposure to Group 1 carcinogens is expected to be fundamentally reduced.μš©μ ‘ μ‹œμ—λŠ” IARC 지정 Group 1 λ°œμ•”λ¬Όμ§ˆμΈ μš©μ ‘ 흄과 6κ°€ 크둬이 λ°œμƒν•˜λ©°, 선행연ꡬ에 λ”°λ₯΄λ©΄ μ „μ„Έκ³„μ˜ μ•½ 11,000만λͺ…μ˜ κ·Όλ‘œμžκ°€ μž‘μ—…μ‹œκ°„ λ™μ•ˆ μš©μ ‘ 흄에 λ…ΈμΆœλœλ‹€ λ°ν˜€μ§„ λ°” μžˆλ‹€. μ΄λŸ¬ν•œ μš©μ ‘ 흄과 6κ°€ 크둬은 μš©μ ‘ μ’…λ₯˜, μš©μ ‘ 쑰건, ν™˜κ²½μ˜ν–₯, μš©μ ‘ 재료 λ“±μ˜ λ‹€μ–‘ν•œ μš”μΈμ— μ˜ν•΄ λ°œμƒ νŠΉμ„±μ΄ λ‹€λ₯΄λ‹€. λ§Žμ€ 선행연ꡬ듀을 ν†΅ν•΄μ„œλŠ” μš©μ ‘μ˜ μ’…λ₯˜λ³„ μš©μ ‘ 흄 및 μœ ν•΄μΈμžμ˜ λ°œμƒ νŠΉμ„±μ— λŒ€ν•΄ μ—°κ΅¬λœ λ°” 있고, μš©μ ‘ μ „λ₯˜, μ „μ•• λ“±μ˜ μš©μ ‘ 쑰건에 따라 μš©μ ‘ 흄과 6κ°€ 크둬의 λ°œμƒμ˜ 변화에 λŒ€ν•΄ κΈ°μˆ ν•œ λ°” μžˆλ‹€. ν•˜μ§€λ§Œ, μž‘μ—…ν˜„μž₯ λ‚΄μ—μ„œλŠ” μš©μ ‘ μ‹œ μš©μ ‘μ˜ μ„±λŠ₯이 κ°€μž₯ μ€‘μš”ν•˜λ©°, μ΄λŸ¬ν•œ μš©μ ‘μ˜ μ„±λŠ₯ μœ μ§€λ₯Ό μœ„ν•΄ μš©μ ‘ 쑰건을 λ³€κ²½ν•˜μ§€ λͺ»ν•˜λŠ” κ²½μš°λ“€λ„ λ”λŸ¬ μ‘΄μž¬ν•œλ‹€. ν•˜μ§€λ§Œ, μ΄λŸ¬ν•œ μš©μ ‘ 재료의 화학적 μ„±λΆ„ ν•¨λŸ‰μ— 따라 λ°œμ•”λ¬Όμ§ˆμΈ μš©μ ‘ 흄과 6κ°€ 크둬의 λ°œμƒμ΄ μ–΄λ–»κ²Œ λ³€ν•˜λŠ” 지 κΈ°μˆ ν•œ μ—°κ΅¬λŠ” 적닀. 이에 따라, λ³Έ μ—°κ΅¬μ—μ„œλŠ” μ‹œμž₯ 점유율이 높은 피볡아크 μš©μ ‘κ³Ό ν”ŒλŸ­μŠ€ μ½”μ–΄λ“œ 아크 μš©μ ‘μ„ λŒ€μƒμœΌλ‘œ μš©μ ‘μž¬λ£Œ 성뢄을 λ‹¬λ¦¬ν•˜μ—¬ μ œμ‘°ν•œ μš©μ ‘ μž¬λ£Œλ“€μ˜ μš©μ ‘ μ‹œ 흄 및 6κ°€ 크둬 λ°œμƒλŸ‰μ„ ν‰κ°€ν•˜μ—¬ 톡계적 좔정을 톡해 흄, 6κ°€ 크둬 저감에 영ν–₯을 λΌμΉ˜λŠ” μš©κ°€μž¬ 성뢄을 μΆ”μ •ν•˜κ³ μž ν•œλ‹€. 자체 μ„±λŠ₯ 평가 기쀀을 λ§Œμ‘±ν•˜λŠ” 피볡아크 μš©μ ‘λ΄‰ 9 μ œν’ˆ, ν”ŒλŸ­μŠ€ μ½”μ–΄λ“œ 와이어 8 μ œν’ˆμ— λŒ€ν•΄ μš©μ ‘ μ’…λ₯˜λ³„ ν†΅μΌλœ μš©μ ‘ 쑰건 ν•˜μ—μ„œ μš©μ ‘μ„ μ‹€μ‹œ ν›„, 흄을 ν¬μ§‘ν–ˆλ‹€. ν¬μ§‘λœ 흄은 μ€‘λŸ‰ 뢄석을 톡해 흄 λ°œμƒλŸ‰μ„ μ‚°μΆœν•˜κ³ , IC-UV/vis둜 6κ°€ 크둬 ν•¨λŸ‰μ„, μš©μ ‘ μž¬λ£Œμ— λŒ€ν•΄ XRF둜 성뢄을 λΆ„μ„ν•˜μ˜€λ‹€. μš©μ ‘μž¬λ£Œ λ‚΄ 각 화학적 μ„±λΆ„λ“€μ˜ ν•¨λŸ‰, 흄 λ°œμƒλŸ‰, 흄 쀑 6κ°€ 크둬 ν•¨λŸ‰ 및 6κ°€ 크둬 λ°œμƒλŸ‰μ„ μ‚°μΆœν•œ ν›„, μ΄λ“€μ˜ κΈ°μ‘΄ μ œν’ˆ λŒ€λΉ„ κ°’μ˜ 변화에 λŒ€ν•œ ν†΅κ³„μ μœΌλ‘œ μœ μ˜ν•œ 차이가 μžˆλŠ”μ§€ κ²€μ •ν•˜μ˜€λ‹€. κ·Έ λ’€, 흄 λ°œμƒλŸ‰, 흄 쀑 6κ°€ 크둬 ν•¨λŸ‰ 및 6κ°€ 크둬 λ°œμƒλŸ‰μ„ 각각 μ’…μ†λ³€μˆ˜λ‘œ, μš©μ ‘ 재료 쀑 νŠΉμ • μ„±λΆ„ ν•¨λŸ‰μ„ λ…λ¦½λ³€μˆ˜λ‘œ 상관뢄석을 톡해 흄, 6κ°€ 크둬 λ°œμƒμ— 영ν–₯을 λΌμΉ˜λŠ” μš©κ°€μž¬ 성뢄을 ν†΅κ³„μ μœΌλ‘œ μΆ”μ •ν•˜μ˜€λ‹€. 상관뢄석 κ²°κ³Όλ₯Ό λ°”νƒ•μœΌλ‘œ, μš©κ°€μž¬μ— 일정 μ΄μƒμ˜ ν•¨λŸ‰μœΌλ‘œ ν¬ν•¨λœ 성뢄에 λŒ€ν•΄ λ‹€μ€‘νšŒκ·€λΆ„μ„μ„ μœ„ν•œ νšŒκ·€λͺ¨ν˜•μ„ 섀계해 λΆ„μ„ν•˜μ˜€λ‹€. λ§ˆμ§€λ§‰μœΌλ‘œ, 톡계적 차이λ₯Ό 보인 μ„±λΆ„λ“€ 및 선행연ꡬ듀을 톡해 μ œμ‹œλœ μ„±λΆ„λ“€, κ°œλ³„μ›μ†Œκ°„ 상관뢄석 결과와 λ‹€μ€‘νšŒκ·€λΆ„μ„ 결과듀을 λ°”νƒ•μœΌλ‘œ μš©μ ‘μž¬λ£Œ λ‚΄ μ„±λΆ„ λ°°ν•© μˆ˜μ‹μ„ 섀계해 각 μ’…μ†λ³€μˆ˜μ™€ 상관뢄석을 μ§„ν–‰ν•˜μ˜€λ‹€. 9 μ’…λ₯˜μ˜ 피볡아크 μš©μ ‘ μ œν’ˆμ˜ μš©μ ‘μ‹œκ°„λ‹Ή 흄 λ°œμƒλŸ‰μ€ 198.0-289.3 mg/min으둜 κΈ°μ‘΄ λŒ€λΉ„ μ΅œλŒ€ 26.7%, 평균 20%의 저감이 κ°€λŠ₯ν–ˆλ‹€. μš©μ ‘μ‹œκ°„λ‹Ή 6κ°€ 크둬 λ°œμƒλŸ‰μ€ 5.34~7.98 mg/min으둜 κΈ°μ‘΄ λŒ€λΉ„ μ΅œλŒ€ 24.8%, 평균 3.4%의 저감이 κ°€λŠ₯ν–ˆλ‹€. 8 μ’…λ₯˜μ˜ ν”ŒλŸ­μŠ€ μ½”μ–΄λ“œ 아크 μš©μ ‘ μ œν’ˆμ˜ μš©μ ‘ μ‹œκ°„λ‹Ή 흄 λ°œμƒλŸ‰μ€ 590.4~821.1 mg/min으둜 κΈ°μ‘΄ λŒ€λΉ„ μ΅œλŒ€ 23.5%, 평균 10.8% 저감이, 6κ°€ 크둬 λ°œμƒλŸ‰μ˜ 경우 0.34~3.31 mg/min으둜 κΈ°μ‘΄ λŒ€λΉ„ μ΅œλŒ€ 89.7%, 평균 47.1% λ°œμƒλŸ‰ 저감이 κ°€λŠ₯ν–ˆλ‹€. λ˜ν•œ, 피볡아크 μš©μ ‘κ³Ό ν”ŒλŸ­μŠ€ μ½”μ–΄λ“œ 아크 μš©μ ‘μž¬λ£Œμ˜ μ›μ†Œ ν•¨λŸ‰λ³„ 흄 λ°œμƒλŸ‰κ³Όμ˜ 상관뢄석 κ²°κ³Ό, 피볡아크 μš©μ ‘μ˜ 경우 F, K Ca, Naκ°€ μš©μ ‘μ‹œκ°„λ‹Ή 흄 λ°œμƒλŸ‰κ³Ό, Cr, Tiκ°€ μš©μ ‘μ‹œκ°„λ‹Ή 6κ°€ 크둬 λ°œμƒλŸ‰κ³Ό ν†΅κ³„μ μœΌλ‘œ μœ μ˜ν•œ μˆ˜μ€€μœΌλ‘œ 상관성을 λ³΄μ΄λŠ” 것을 확인할 수 μžˆμ—ˆλ‹€. FCAW의 경우 F, K, Na ν•¨λŸ‰μ΄ μš©μ ‘μ‹œκ°„λ‹Ή 흄 λ°œμƒλŸ‰κ³Ό, Na, K, Si, Zr, Fκ°€ μš©μ ‘μ‹œκ°„λ‹Ή 6κ°€ 크둬 λ°œμƒλŸ‰κ³Ό ν†΅κ³„μ μœΌλ‘œ μœ μ˜ν•œ 상관성을 λ³΄μ΄λŠ” 것을 확인할 수 μžˆμ—ˆλ‹€. λ‹€μ€‘νšŒκ·€λΆ„μ„ κ²°κ³ΌλŠ” λŒ€λΆ€λΆ„μ˜ νšŒκ·€λͺ¨ν˜•μ—μ„œ λ…λ¦½λ³€μˆ˜ κ°„μ˜ 간섭에 μ˜ν•œ 닀쀑곡선성 λ¬Έμ œκ°€ λ„μΆœλ˜μ–΄ νšŒκ·€λͺ¨ν˜•μ˜ 적합도가 λ–¨μ–΄μ§€λŠ” κ²ƒμœΌλ‘œ μΆ”μ •λ˜μ—ˆλ‹€. 이에 따라, λ³Έ μ—°κ΅¬μ—μ„œλŠ” 흄 λ°œμƒλŸ‰, 흄 쀑 6κ°€ 크둬 ν•¨λŸ‰, 6κ°€ 크둬 λ°œμƒλŸ‰κ³Ό ν†΅κ³„μ μœΌλ‘œ μœ μ˜ν•œ μˆ˜μ€€μ˜ 상관성을 λ³΄μ΄λŠ” μ„±λΆ„ λ°°ν•© μˆ˜μ‹μ„ 피볡아크 μš©μ ‘μ— λŒ€ν•΄ 11가지, ν”ŒλŸ­μŠ€ μ½”μ–΄λ“œ 아크 μš©μ ‘μ— λŒ€ν•΄ 10가지λ₯Ό μ œμ‹œν•˜μ˜€λ‹€. μ’…ν•©μ μœΌλ‘œ, 성뢄을 λ‹€λ₯΄κ²Œ μ œμ‘°ν•œ μš©μ ‘μž¬λ£Œλ“€μ— λŒ€ν•΄ μ„±λŠ₯적 결함 없이 흄 λ°œμƒλŸ‰, 6κ°€ 크둬 λ°œμƒλŸ‰μ„ 저감할 수 μžˆλ‹€λŠ” 것을 증λͺ…ν•˜μ˜€λ‹€. λ˜ν•œ, 피볡아크 μš©μ ‘μ˜ 경우 6κ°€ 크둬 λ°œμƒλŸ‰μ„ μ €κ°ν•˜κΈ° μœ„ν•΄μ„œλŠ” 흄 λ°œμƒλŸ‰μ„ μ€„μ΄λŠ” 것이, ν”ŒλŸ­μŠ€μ½”μ–΄λ“œ 아크 μš©μ ‘μ˜ 경우 6κ°€ 크둬 λ°œμƒλŸ‰μ„ 쀄이기 μœ„ν•΄μ„œλŠ” 흄 쀑 6κ°€ 크둬의 ν•¨λŸ‰μ„ μ€„μ΄λŠ” 것이 μš©μ΄ν•˜λ‹€. λ§ˆμ§€λ§‰μœΌλ‘œ, μš©μ ‘ κ°„ μ‚°ν™”μž‘μš©μ„ 톡해 λ°œμƒλ˜λŠ” 6κ°€ 크둬 λ°œμƒμ„ μ €κ°ν•˜κΈ° μœ„ν•΄ μš©μ ‘ 재료 제쑰 μ‹œ ν™”ν•©λ¬Όλ“€μ˜ μ‚°ν™”μˆ˜, μ „κΈ°μŒμ„±λ„ 등을 κ³ λ €ν•˜μ—¬ κΈˆμ† 크둬 및 크둬 화합물보닀 μ „κΈ°μŒμ„±λ„κ°€ λ†’μ•„ 크둬의 μ‚°ν™”λ₯Ό μ–΅μ œν•˜λŠ” λ¬Όμ§ˆλ“€λ‘œ μš©μ ‘μž¬λ£Œλ₯Ό μ œμ‘°ν•˜λŠ” 것을 ꢌμž₯ν•˜λŠ” 바이닀. λ³Έ μ—°κ΅¬μ—μ„œ μ œμ‹œν•œ μ›μ†Œ ν•¨λŸ‰λ³€ν™”μ— λ”°λ₯Έ 흄 λ°œμƒλŸ‰, 6κ°€ 크둬 λ°œμƒλŸ‰ 식을 μ°Έκ³ ν•˜μ—¬ 흄 λ°œμƒ 및 6κ°€ 크둬 λ°œμƒμ΄ 적은 μš©μ ‘ 재료λ₯Ό μ œμ‘°ν•˜μ—¬ ν˜„μž₯μ—μ„œ 널리 μ‚¬μš©λœλ‹€λ©΄, 근둜자의 1κΈ‰ λ°œμ•”λ¬Όμ§ˆμ— λŒ€ν•œ λ…ΈμΆœ 문제λ₯Ό 근본적으둜 κ°œμ„ ν•  수 μžˆμ„ κ²ƒμœΌλ‘œ κΈ°λŒ€λ˜λŠ” 바이닀.Abstract 1. Introduction 1 2. Materials and Methods 4 2.1. Study Subject 4 2.1.1. Welding Filler Material 4 2.1.2. Evaluation Condition 7 2.1.3. Study Procedure 9 2.2. Fume & Hexavalent Chromium Generation Rate Test 11 2.2.1. Sampling Strategy 11 2.2.2. Gravimetric Analysis 12 2.2.3. Hexavalent Chromium Analysis 13 2.2.4. Estimation of Generation Rate 14 2.3. Composition Analysis of Welding Filler Material 15 2.3.1. Sampling Strategy 15 2.3.2. Instrumental Analysis 16 2.4. Statistical Analysis 17 3. Results 19 3.1. Fume Generation Rate 19 3.2. Hexavalent Chromium Generation Rate 22 3.3. Chemical Composition of Welding Filler Material 26 3.4. Correlation Analysis by Each Component 29 3.5. Multiple Linear Regression Analysis 30 3.6. Correlation Analysis by Proposed Formula 32 4. Discussion 35 5. Conclusions 40 6. References 41 Supplementary Materials 45 Abstract in Korean 60석
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