NACE CIP 2 EXAM WITH QUESTIONS AND ANSWERS

Describe passivation - answerPassivation is the formation of a protective oxide Film on the surface reducing its chemical activity and its ability to corrode Describe the following factors and how they affect corrosion - answerOxygen: oxygen increases the rate of corrosion temperature Temperature: corrosion usually accelerated with increasing temperature Chemical salts: increase the rate of corrosion by increasing the efficiency of the electrolyte humidity: the wetter the environment, the more corrosion is likely to occur pollutants and acid gases: all promote corrosion Two broad categories of corrosion can be described as - answerGeneral and localized Describe galvanic corrosion - answerGalvanic corrosion is an electrochemical action of two dissimilar metals in the presence of an electrolyte and an electron conductive path, Which occurs when the dissimilar metals come into contact Describe cathodic protection - answerCathodic protection is the reduction or elimination of corrosion by making the structure to be protected a cathode by means of impressed current or attachment to a galvanic anode The two primary types of cathodic protection are - answerImpressed current and galvanic (sacrificial) impressed current power sources include: - answer1. Generators 2. Fuel cells 3. Wind powered cells 4. Thermoelectric cells 5. Rectified commercial power 6. Solar Cells Describe cathodic disbondment - answerThe separation of the coating from the surface through hydroxyl formation due to increased ( made more negative ) potential. Describe dehumidification - answerDehumidification is the process of removing moisture vapor from the air to lower its dew point When planning enclosures the following minimum requirements should be considered - answerMust be large enough to contain the whole work area. Not be larger than the performance capabilities of the dehumidification equipment. Be sturdy enough to hold up to intended work activities, potential loads, and a possible inclement weather. Have minimal leakage to maintain proper environmental conditions and ensure the dehumidification system operates efficiently. Describe air turns (air changes) - answerThe air turnover principal illuminates air stratification, or layering, in large open spaces by recirculating the hot air that becomes trapped in the higher spaces. The number of times it does this per hour is called air turns. At & below what relative humidity does corrosion virtually cease - answer40% Describe two ways to reduce the relative humidity of the boundary layer - answerIncrease the surface temperature and reduce moisture content by dehumidification