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Defined Benefit Retirement Plan
A type of pension plan whereby the employer promises to make
pension payments to retired employees in specified amounts,
regardless of the performance of the fund. Because the employees'
total years of service and their length of retirement are
uncertain, the employer's future liabilities must be estimated
and can fluctuate over time.
Defined Contribution Retirement Plan
A pension plan in which the employer promises to make specified
contributions to the pension fund, but the amount of pension
benefits ultimately paid to retired employees depends on how
well the pension fund's assets are managed. There are no balance
sheet items for Defined Contribution Plans because all liabilities
are satisfied in full each year.
Desulfurization
WHAT Operation that injects a
chemical mixture into a ladle full of hot metal to remove
sulfur prior to its charging into the Basic Oxygen Furnace.
WHY Sulfur enters the steel from
the coke in the blast furnace smelting operation, and there
is little the steelmaker can do to reduce its presence. Because
excess sulfur in the steel impedes its welding and forming
characteristics, the mill must add this step to the steelmaking
process.
Direct Reduced Iron (DRI)
WHAT Processed iron ore that is
iron-rich enough to be used as a scrap substitute in electric
furnace steelmaking.
WHY As mini-mills expand their
product abilities to sheet steel, they require much higher
grades of scrap to approach integrated mill quality. Enabling
the mini-mills to use iron ore without the blast furnace,
DRI can serve as a low residual raw material and alleviate
the mini-mills' dependence on cleaner, higher-priced scrap.
HOW The impurities in the crushed
iron ore are driven off through the use of massive amounts
of natural gas. While the result is 97% pure iron (compared
with blast furnace hot metal, which, because it is saturated
with carbon, is only 93% iron), DRI is only economically feasible
in regions where natural gas is attractively priced.
Drawn-Over-Mandrel
A procedure for producing specialty tubing using a drawbench
to pull tubing through a die and over a mandrel, giving excellent
control over the inside diameter and wall thickness. Advantages
of this technique are its inside and outside surface quality
and gauge tolerance. Major markets include automotive applications
and hydraulic cylinders.
Drill Pipe
Pipe used in the drilling of an oil or gas well. Drill pipe
is the conduit between the wellhead motor and the drill bit.
Drilling mud is pumped down the center of the pipe during
drilling, to lubricate the drill bit and transmit the drilled
core to the surface. Because of the high stress, torque and
temperature associated with well drilling, drill pipe is a
seamless product.
Ductility
Ability of steel to undergo permanent changes in shape without
fracture at room temperature.
Dumping
Dumping occurs when imported merchandise is sold in, or for
export to, the domestic market at less than the normal value
of the merchandise, i.e., a price which is less than the price
at which identical or similar merchandise is sold in the comparison
market, the home market (market of exporting country) or third-country
market (market used as proxy for home market in cases where
home market cannot be used). The normal value of the merchandise
cannot be below the cost of production.
Dumping Margin
The amount by which the normal value exceeds the export price
or constructed export price of the subject merchandise.
Duplex
A category of stainless steel with high amounts of chromium
and moderate nickel content. The duplex class is so named
because it is a mixture of austenitic (chromium-nickel stainless
class) and ferritic (plain chromium stainless category) structures.
This combination was originated to offer more strength than
either of those stainless steels. Duplex stainless steels
provide high resistance to stress corrosion cracking (formation
of cracks caused by a combination of corrosion and stress)
and are suitable for heat exchangers, desalination plants,
and marine applications. |
