Exam 1: Corrosion and Materials

300 Series SS can suffer pitting corrosion, crevice corrosion and ________ in fresh, blackish and salt water.

Major factors affecting sulfidation are alloy composition, temperature and ________.

With HF acid corrosion, oxygen contamination _________ the corrosion rate of carbon steel and promotes accelerated corrosion and SCC of Alloy 400.

HCL acid corrosion is found in several units, especially _______ and ________, units, hydroprocessing units and catalytic reformer units.

Hydrogen stress cracking is the same mechanism that is responsible for sulfide stress corrosion cracking in wet H₂S environments except that HF acid is generating the __________.

Primarily hot-wall piping and equipment in the following units can be affected by graphitization. FCC, catalytic reformer and ______.

Hardness is primarily an issue with SSC. Typical low strength carbon steels should be controlled to produce weld hardness less than ________.

MIC is often found in _________, bottom water of storage tanks, piping with stagnant or low flow and piping in contact with some soils.

300 Series SS can be used for sour water service at temperatures below ____________, where Chloride SCC is not likely.

Atmospheric corrosion:

300 Series SS, 5Cr, 9Cr and 12Cr alloys are not susceptible to ________ at conditions normally seen in refineries.

Atmospheric corrosion is of greatest concern in:

With creep, increased stress due to loss in thickness from corrosion will ________ time to failure.

Sigma phase occurs in Ferritic, martensitic, austenitic and duplex stainless steels when exposed to temperatures in the range of _____.

Which of these materials exhibit an endurance limit below which fatigue cracking will not occur?

Inspection for wet H2S damage generally focuses on _____ and ______.

With sulfuric acid corrosion, the presence of oxidizers can _______ the corrosion rate.

Metal dusting is preceded by ________ and is characterized by rapid metal wastage.

The presence of _________ can destabilize the scale and turn it into a nonprotective scale.

_________ significantly increases the probability and severity of blistering, HIC and SOHIC.