Corrosion direct

Indirect Probes Some types of probes do not measure corrosion directly, but yield measurements that also are useful in detecting corrosion. Examples include ... 

Corrosion (direct cause) due to Design error (basic or root cause) not recovered by Inspection (failure of recovery)... 

Hydrofluoric acid causes two types of corrosion, direct corrosion, in which iron fluoride is formed, and stress corrosion, in which the metal cracks. Electrolytic corrosion can also take place when the acid becomes diluted with water and two dissimilar metals or carbon are used. Because of the possibility of stress corrosion, all vessels in acid service must be stress-relieved. Monel is also subject to stress corrosion and must be stress-relieved. Care must be taken in stress-relieving Monel that sulfur or sulfur compounds do not come in contact with the Monel either before or during the heat treatment. 

In consideration of some operational difficulties, like biofouling and corrosion, directly related to the feed-water source, more reliable water sources have been evaluated by the Evides Industriewater that owns and operates this plant, like anaerobic groundwater and sweet tertiary wastewater. 

NACE RP0502 Pipeline External Corrosion Direct Assessment Methodology http //www. nace.org/product.asp =SKU=51300%2DSG ProdName=04187- -External+Corrosion+Direct+ Assessment (accessed Dec 2004). 

Early reports showing the influence of halides on corrosion processes on atomic level were presented for Cu corrosion in chloride media by Suggs and fiard" and for Pd in iodide media by Sashikata et al. ° For copper dissolution the most favourable corrosion sites were identified and the Cu(100) 100 direction was found to be the most preferred corrosion direction.In the case of Pd corrosion, it was found that corrosion is an iodine structure dependent reaction and that dissolution takes place anisotropically along a step ahgned in the 100 direction without disruption of the iodine adlattice. ... 

Equipment. The experiment must be conducted in a well-ventilated fume hood. As DMTST is toxic and corrosive direct contact with skin must be avoided. 

The first barrier to sea water ingress is the bitumen which covers the whole SGI. This bitumen is assumed to degrade linearly in 100 years from full to zero effectiveness, modelled by the bitumen factor k(, = O.Olt (t 100 years). The fuel, and hence the fission products and actinides, is surrounded above and below by at least 300 mm of solidified Pb-Bi coolant, and multiple layers of SS. Using the most pessimistic estimates of corrosion rates and thicknesses, the minimum time for water ingress to the fuel via corrosion directly from above or below is over 40 000 years. This timescale is much longer than that of ingress through the EPR tubes and ECTs hence, this method will be assumed to be the primary means of release and is studied in more detail below. 

ASTM D 2688 Test Method for Corrosivity of Water in the Absence of Heat Transfer (Weight Loss Methods) Provides weight loss methods to evaluate corrosion directly in piping systems. 

RP0502—Pipeline External Corrosion Direct Assessment Methodology ... 

External Corrosion Direct Assessment (ECDA) of Buried Pipelines [33,34]... 

The EDCA process incorporates standard techniques for compiling historical information, pipehne and soil surveys, external pipeline inspections, and data einalysis. The procedure includes no new measurement techniques, but it does allow for the future addition of such techniques. Some rules ind information about EDCA arc present in NACE RP0502—Pipeline External Corrosion Direct Assessment Methodology. 

Kroon, D. H., External Corrosion Direct Assessment of Buried Pipelines The Process," Materials Performance, Vol. 42, June 2003, pp. 28-32. 

Equipment. The experiment is best conducted in a well-ventilated fiime hood. As iodine is corrosive direct contact with skin or inhalation of its vapour should be avoided. 

Kroon DH. External corrosion direct assessment of buried pipelines The Process. Materials Performance 2003 42 28-32. 

NACE RP0502-2002—Standard Recommended Practice for Pipeline External Corrosion Direct Assessment Methodology. Houston, Tex. NACE International, 2002. 

TadepaUy VP, Hendren ES. Internal corrosion direct assessment Refining the method throughnew decision support models. CORROSION 2005, Paper 178. Houston, Tex., NACE International, 2005. 

V. V. Lagad, S. Srinivasan, R.D. Kane 2008. Facilitating internal corrosion direct assessment using... 

Figure 9.1.1 Device to determine the transcutaneous electrical resistance (TER) test through the rat skin disc (B.40. Skin corrosion, Directive 2000/33/EC).

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