Exam 1: Corrosion and Materials

Which of the following materials is least affected by atmospheric corrosion?

Temperature, ________ and stress are critical factors of stress rupture. This is usually found in furnaces with coking tendencies and fired heater tubes.

In a pump, the difference between the actual pressure, or head, of a liquid available (measured on the suction side) and the vapor pressure of that liquid is called Net Positive Suction Head (NPSH) available. The minimum head required to prevent cavitation with a given liquid at a given flow rate is called Net Positive Suction Head __________. Inadequate NPSH can result in cavitation.

Which of the following is not a primary initiating point for thermal fatigue?

Corrosion protection in the boiler is accomplished by laying down and continuously maintaining a layer of _____.

__________ is a form of damage found mostly in older vintage carbon steels and C-0.5 Mo low alloy steels under the combined effects of deformation and aging at an intermediate temperature.

Thermal fatigue cracks usually:

____________ are characterized by a localized loss in thickness in the form of pits, grooves, gullies, waves, rounded holes and valleys. These losses often exhibit a directional pattern.

Sensitization occurs in the _____ to _______ range.

Stainless steel cyclones, piping ductwork and valves in high temperature FCC regeneration service are susceptible areas for _________.

Units where graphitization may be suspected are the FCCU and the _____ unit.

Soils having high moisture content, high dissolved salt concentrations and high ________ are the most corrosive.

Lean amine is generally not corrosive because they have either low conductivity and/or high pH. Corrosion rates increase with increasing temperatures, particularly in rich amine service. Temperatures above _________ can result in acid gas flashing and severe localized corrosion.

_________ is most likely found in hard weld and heat-affected zones and in high strength components.

________ greatly increases the probability and severity of blistering, HIC and SOHIC damage.

In general, the resistance of carbon steel and other alloys to High temperature corrosion is determined by the ________ content of the material.

Carbonate stress corrosion cracking is the term applied to surface breaking or cracks that occur adjacent to carbon steel welds under the combined action of ____________ and ___________ in carbonate containing systems.

The accepted way to test for temper embrittlement is ________.

Susceptibility of an alloy to sulfidation is determined by its ability to form protective _________.

_________ is the sudden rapid fracture under stress (residual or applied) where the material exhibits little or no evidence of ductility or plastic deformation.