QUESTIONS WITH MULTIPLE
CHOICES GUARANTEED ANSWERS
a term that refers to a type of metallurgical structure (austenite) normally found in 300
Series stainless steels and nickel base alloys. - correct answers Austenitic
the 300 Series stainless steels including Types 304, 304L, 304H,
309, 310, 316, 316L, 316H, 321, 321H, 347, and 347H. The "L" and "H" suffixes refer to controlled ranges
of
low and high carbon content, respectively. These alloys are characterized by an austenitic structure. -
correct answers Austenitic stainless steels
steels that do not have alloying elements intentionally added. However, there may
be small amounts of elements permitted by specifications such as SA516 and SA106, for example that
can
affect corrosion resistance, hardness after welding, and toughness. Elements which may be found in
small
quantities include Cr, Ni, Mo, Cu, S, Si, P, Al, V and B. - correct answers Carbon steel
used in amine treating to remove H2S and CO2 from hydrocarbon streams. - correct answers
Diethanolamine (DEA)
a family of stainless steels that contain a mixed austenitic-ferritic structure
including Alloy 2205, 2304, and 2507. The welds of 300 series stainless steels may also exhibit a duplex
structure. - correct answers Duplex stainless steel
a term that refers to a type of metallurgical structure (ferrite) normally found in carbon and
low alloy steels and many 400 series stainless steels. - correct answers Ferritic
,include Types 405, 409, 430, 442, and 446. - correct answers Ferritic stainless steels
the portion of the base metal adjacent to a weld which has not been
melted, but whose metallurgical microstructure and mechanical properties have been changed by the
heat of
welding, sometimes with undesirable effects. - correct answers Heat Affected Zone (HAZ)
describes stepwise internal cracks that connect adjacent
hydrogen blisters on different planes in the metal, or to the metal surface. No externally applied stress is
needed for the formation of HIC. The development of internal cracks (sometimes referred to as blister
cracks) tends to link with other cracks by a transgranular plastic shear mechanism because of internal
pressure resulting from the accumulation of hydrogen. The link-up of these cracks on different planes in
steels has been referred to as stepwise cracking to characterize the nature of the crack appearance. -
correct answers Hydrogen Induced Cracking (HIC)
a family of steels containing up to 9% chromium and other alloying additions for
high temperature strength and creep resistance. The materials include C-0.5Mo, Mn-0.5Mo, 1Cr-0.5Mo,
1.25 Cr-0.5Mo, 2.25Cr-1.0Mo, 5Cr-0.5Mo, and 9Cr-1Mo. These are considered ferritic steels. - correct
answers Low alloy steel
term that refers to a type of metallurgical structure (martensite) normally found in
some 400 series stainless steel. Heat treatment and or welding followed by rapid cooling can produce
this
structure in carbon and low alloy steels. - correct answers Martensitic
include Types 410, 410S, 416, 420, 440A, 440B, and 440C. - correct answers Martensitic stainless steel
used in amine treating to remove H2S and CO2 from hydrocarbon
streams. - correct answers Methyldiethanolamine (MDEA)
,used in amine treating to remove H2S and CO2 from hydrocarbon
streams. - correct answers Monoethanolamine (MEA)
a family of alloys containing nickel as a major alloying element (>30%) including
Alloys 200, 400, K-500, 800, 800H, 825, 600, 600H, 617, 625, 718, X-750, and C276. - correct answers
Nickel base
describes an array of cracks, aligned
nearly perpendicular to the stress, that are formed by the link-up of small HIC cracks in steel. Tensile
strength (residual or applied) is required to produce SOHIC. SOHIC is commonly observed in the base
metal
adjacent to the Heat Affected Zone (HAZ) of a weld, oriented in the through-thickness direction. SOHIC
may
also be produced in susceptible steels at other high stress points, such as from the tip of the mechanical
cracks and defects, or from the interaction among HIC on different planes in the steel. - correct answers
Stress oriented hydrogen induced cracking (SOHIC)
there are four categories of stainless steels that are characterized by their
metallurgical structure at room temperature: austenitic, ferritic, martensitic and duplex. These alloys
have
varying amounts of chromium and other alloying elements that give them resistance to oxidation,
sulfidation
and other forms of corrosion depending on the alloy content. - correct answers Stainless steel
What hydrocarbon stream produced on a crude unit will hat the most sulfur.
A. Gas Oil
B. Kerosene
C. Diesel
D. Gasoline - correct answers A. Gas Oil
, What is the typical length of time for a coke drum cycle on a DCU.
A. 1 hour
B. 10 hours
C. 1 day
D. 10 days - correct answers C. 1 Day
When evaluation the water chemistry, what is the desired pH of the condensate (water) that condensed
in the Main Fractionator at the DCU
A. 1.0 to 2.0
B. 4.0 to 5.0
C. 6.0 to 7.0
D 9.0 to 10.0 - correct answers C. 6.0 to 7.0
In many refinery units, water and H2s combine to form which of the following corrosive agents.
A. Wet H2s
B. Sulfuric Acid
C. Sodium Hydroxide
D. Sulfur Naptha Acid - correct answers A. Wet H2S
A Catalytic Cracking Unit will do which of the following:
A. Combine small hydrocarbon chains
B. Thermally crack hydrocarbon chains into smaller chains
C. Produce significant amounts of gasoline