• 제목/요약/키워드: Carbon Steel Pipe

검색결과 140건 처리시간 0.022초

상수도 배급수관망의 부식방지를 위한 인산염계 방청제 적용에 관한 연구 (Effect of Phosphate-based Inhibitors on Pipe Corrosion of Drinking Water Supply)

  • 이윤진;남상호
    • 한국환경보건학회지
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    • 제29권3호
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    • pp.65-71
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    • 2003
  • The injection concentration of corrosion inhibitor increases under the pH 7, temperature of 2$0^{\circ}C$, and alkalinity of 35 mg/l (as CaCO$_3$), the corrosion rate gradually decreased. When the corrosion inhibitor of 10 mg/l is injected, the corrosion rate for carbon steel pipe, galvanized steel pipe, and copper pipe reduces for 37, 66 and 61 % respectively that it is more efficient on galvanized steel pipe and copper pipe. As a result of examination of corrosion rate at pH 6, 7, and 8 when injecting 10 mg/l of corrosion inhibitor under the conditions of 2$0^{\circ}C$ in water temperature and 35 mg/l (as CaCO$_3$) in alkalinity, the efficiency of the corrosion inhibitor increases as the pH increases. For carbon steel pipe, it does not show much a difference with the change of the pH condition, but galvanized steel pipe and copper pipe clearly show the corrosion rate depending on the change of the pH condition. The efficiency of corrosion inhibitor is low as the concentration of residual chlorine is high, but it does not show a great influence at 0.4 mg/l or less. For each pipe type, in the case of carbon steel pipe, the range of increase of corrosion speed following the residual chloride is higher than the other pipe types. In the meantime, the effect following the residual chlorine in copper pipe is low.

수도관의 부기거동에 관한 연구 (Corrosion Behaviour of Water Pipes)

  • 김원만;박영식
    • 환경위생공학
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    • 제7권1호
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    • pp.1-16
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    • 1992
  • Corrosion of pipes Is one of the most serious problems in the maintenance of water worlds. Corrosion is promoted not only by physical factors such as temperature, but also by electrochemical factors including concentration of soluble metal ions, chlorine ion, pH, DO and microorganisms. Corrosion products also affect corrosion rate. In this research, study results are summarized as follows ; 1) Corrosion test was performed for 4 weeks at $70^{\circ}C$, pH 7.0 with specimens of 4 types of metal materials used as service pipes. Corrosion rate and S.E.M were analyzed. The results were showed that corrosion 1.ate of carbon steel pipe was 4.10~5.22 $mg/\textrm{cm}^2$ . week, galvanized steel pipe 0.98~1.34$mg/\textrm{cm}^2$. week, Copper pipe 0.02~0.04$mg/\textrm{cm}^2$. week, stainless steel pipe 0.05~ 0.10$mg/\textrm{cm}^2$ . week. 2) When corrosion rate was tested for tile types of pipes at pH 7 and both $25^{\circ}C$ and $75^{\circ}C$, avaerage corrosion rate for 6 weeks at $25^{\circ}C$ Ivas 2.26$mg/\textrm{cm}^2$ . week in carbon steel pipe, 1.99$mg/\textrm{cm}^2$. week in galvanized steel pipe, 0.26 $mg/\textrm{cm}^2$. week in stainless steel pipe. At $87^{\circ}C$, average corrosion rate for 4 weeks u.3s 4.56 $mg/\textrm{cm}^2$. week in carbon steel pipe,

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Localized Corrosion of Zn-Plated Carbon Steel Used as a Fire Sprinkler Pipe

  • Lee, Jin Hee;Lee, You-Kee;Lee, Kyu Hwan;Kim, Dong-Kyu;Lee, Sung Gun;Lee, Sang Hwa;Kim, Insoo
    • Corrosion Science and Technology
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    • 제8권4호
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    • pp.148-152
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    • 2009
  • The failure of a Zn-plated carbon steel pipe that served as a fire sprinkler was investigated in terms of the pipe's corrosion products. The pipes leaked through holes formed beneath the tubercles. The formation of oxygen concentration cell involves colonization of metal surface by aerobic bacteria or other slime formers, and anodic reaction beneath tubercle is accelerated by the presence of SRB, leading to the formation of hole beneath tubercle.

탄소강관의 ERW 용접부 홈부식 손상에 관한 연구 (A Study on Grooving Corrosion at the Weld of a Low Carbon Steel Pipe Made by Electrical Resistance Welding)

  • 김용;이보영
    • Journal of Welding and Joining
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    • 제22권5호
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    • pp.58-64
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    • 2004
  • Although leakage at a low carbon steel pipe made by electrical resistance welding (ERW) was reported due to grooving corrosion, the cause for the corrosion has not yet been cleared. In order to clarify the main cause, failure analysis on the leaked pipe was carried out, followed by metallographic investigation and corrosion test for the various ERW pipe made with different welding heat input. The microstructure, particularly inclusion content, of the weldment is dependant on the welding heat input applied. For an improper low heat input, the amount of inclusion at the weld was high. High inclusion content accelerated grooving corrosion at the weld. It is therefore that welding heat input should be controlled based on the carbon content of the pipe in order to improve the corrosion resistance of the ERW pipe.

Adsorption behaviour of film-forming amine on pre-oxidized carbon steel surface

  • Genxian, Lin;Yun, Sun;Canshuai, Liu;Jun, Fang;Lijun, Song;Bin, Liu
    • Nuclear Engineering and Technology
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    • 제54권4호
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    • pp.1185-1194
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    • 2022
  • The maintenance of condenser main pipe is the key to achieve film-forming amine maintenance effectiveness. In this work, oxygen content, pH and temperature of the solution were controlled to simulate the condition of condenser main pipe, and magnetite coated carbon steel sample was prepared by pre-oxidization. CAM was used to characterize the hydrophobicity of film formed samples. Hydrophobic film was formed on pre-oxidized carbon steel samples when octadecylamine concentration reaches 20 mg/kg. SEM, EDS, EIS, and PD were used to characterize the influence of octadecylamine concentration on maintenance effectiveness. It was found that the maintenance effectiveness was enhanced and the corrosion rate was suppressed with the increase of octadecylamine concentration. FIB and TEM were used to detect the adsorbed octadecylamine film thickness founding that octadecylamine adsorbed onto the surface of pre-oxidized carbon steel by multi-layer adsorption mechanism.

ASSESSMENT OF WALL-THINNING IN CARBON STEEL PIPE BY USING LASER-GENERATED GUIDED WAVE

  • Kim, Do-Youn;Cho, Youn-Ho;Lee, Joon-Hyun
    • Nuclear Engineering and Technology
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    • 제42권5호
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    • pp.546-551
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    • 2010
  • The objective of this research is to estimate the crack location and size of a carbon steel pipe by using a laser ultrasound guided wave for the wall thinning evaluation of an elbow. The wall thinning of the carbon steel pipe is one of the most serious problems in nuclear power plants, especially the wall thinning of the carbon steel elbow caused by Flow-Accelerated Corrosion (FAC). Therefore, a non-destructive inspection method of elbow is essential for the nuclear power plants to operate safely. The specimens used in this study were carbon steel elbows, which represented the main elements of real nuclear power plants. The shape of the wall thinning was an oval with a width of 120mm, a length of 80mm, and a depth of 5mm. The L(0,1) and L(0,2) modes variation of the ultrasound guided wave signal is obtained from the response of the laser generation/air-coupled detection ultrasonic hybrid system represent the characteristics of the defect. The trends of these characteristics and signal processing were used to estimate the size and location of wall thinning.

자전거 프레임용 CFRP 파이프 설계제작 (Design and Manufacture of CFRP Pipe for Bicycle Frame)

  • 이범성
    • 한국정밀공학회지
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    • 제20권6호
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    • pp.130-137
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    • 2003
  • The pipe of CFRP for bicycle frame is designed and made for light weight of bicycle and then its suitability to bicycle frame is verified by comparing the other material i.e. steel, Cr-Mo steel, Al alloy pipe for bicycle frame. The pipe of CFRP is laminated to [0/$\pm$45]$_T$ and made by tape winding method and then its degree of light weight is evaluated by comparing the other pipes which is made by steel etc.

주기적 하중을 받는 SCH 40 3-Inch 탄소강관엘보의 소산에너지 기반의 손상지수 평가 (Damage Index Evaluation Based on Dissipated Energy of SCH 40 3-Inch Carbon Steel Pipe Elbows Under Cyclic Loading)

  • 김성완;윤다운;전법규;김성도
    • 한국구조물진단유지관리공학회 논문집
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    • 제25권1호
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    • pp.112-119
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    • 2021
  • 지진하중으로 인한 배관계통의 파괴모드는 라체트를 동반하는 저주기 피로파괴이며 비선형 거동이 집중되고 파손이 발생하는 요소는 엘보인 것으로 나타났다. 본 연구에서는 저주기 피로에 의한 SCH 40 3인치 탄소강관엘보의 파괴기준을 정량적으로 표현하기 위하여 한계상태를 누수로 정의하고 면내반복가력실험을 수행하였다. 배관계통에서 지진하중에 취약한 요소인 탄소강관엘보에 대하여 모멘트-변형각의 관계를 이용한 손상지수를 나타내었으며 힘-변위의 관계를 이용하여 산정된 손상지수와 비교-분석하였다. 탄소강관엘보에 대하여 반복되는 외력에 의한 소산에너지에 기반을 둔 손상지수로서 누수가 발생한 한계상태를 정량적으로 표현하였다.

유한요소법을 이용한 분기배관의 성형해석에 관한 연구 (A study on the Analyses of T-branch Pipe Forming using a Finite Element Method)

  • 남준석;백창선;임광규;사공성호;소수현;민경탁
    • 한국화재소방학회논문지
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    • 제21권1호
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    • pp.98-105
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    • 2007
  • 본 연구에서는 소방 건축분야에 가장 많이 사용되는 배관인 배관용 탄소강관 및 이에 상응하는 스테인리스 강관을 분기배관으로 제작이 가능한지 여부를 상용유한요소프로그램(ABAQUS)을 이용하여 확인하였다. 이러한 배관을 분기배관으로 성형할 경우 심이 없는 배관 사용을 원칙으로 하고 배관에 심이 있는 경우 심과 정반대방향을 성형면으로 하여야 한다. 배관의 성형시 플러그의 경사면과 길이가 성형에 가장 큰 영향을 미치는 요소임을 알 수 있었다. 분기배관의 성형해석결과를 토대로 분기부분의 최소 높이와 두께를 제안했다.