R
R Enamel
An unpigmented enamel used to
increase resistance to corrosion, or decrease bleaching effect of
tinplate on food can interiors.
Red Rust
A reddish brittle coating of iron
oxide which develops on an uncoated or coated steel surface when oxygen
in the atmosphere mixes with iron.
Reel Breaks
Fractured base metal normally
caused by poor leveling. It is indicated by light kinks across the width
of the winding coil.
Reflowed Surface
A shiny tin plate product surface
which is achieved by heating the tin coating up to its melting point
(thereby melting the tin) and cooling it back to room temperature.
Ribbing
A coating defect consisting of a
flow mark defect with an appearance similar to corduroy fabric. Ribbing
usually occurs when the flow marks (ribs), from application on the
coater, do not flow out and level the surface of the coating.
Ridge
A hump across the width of the
surface of the coil.
Rockwell (Hardness Tester)
A device used to determine the
hardness of the steel strip. "Rockwell" machines are used to measure
hardness of all WSC’s products.
Rockwell Hardness
Measure of resistance to
penetration when material is exposed to a pointed load. The hardness
numbers obtained by a Rockwell machine are related to the depth of the
impression measured after the load is applied.
Roll Force Cylinder
See A.G.C. Cylinder.
Roll Scale
Oxide of iron
which forms on the surface of steel while it is being heated and rolled.
Much of the scale is cracked and loosened during the rolling operation
and may fall off the piece naturally or be blown off by high-pressure
water sprays or other means.
Roll Forming
1.
An operation used in forming sheet. Strips of sheet are passed between
rolls of definite settings that bend the sheet progressively into
structural members of various contours, sometimes called "molded
sections." 2. A process of coiling sheet into open cylinders.
Roller Level
A staggered system of rolls used
to flatten the steel without any appreciable reduction in gauge.
Rolling Mill
1.
Any of the mills in which
metal undergoes a rolling process. These include the slabbing mill, hot
roll mills, cold roll mills, SR mills, and DR mills. 2. Any
operating unit that reduces gauge by application of loads through
revolving cylindrical rolls; operation can be hot or cold. Weirton
Steel’s room temperature rolling mills include Tandem Mills (Cold Mills)
which are capable of reducing the gauge of 90%, Weirlite Mills (20-45%)
and the Temper Mill (1%). The elevated temperature rolling mill is the
Hot Mill and is capable of reducing the gauge of a slab 92-99%.
Roughing Stand
The first rolling stand through
which metal passes during hot rolling. Once reduced by the roughing
stands, the metal continues on to the finishing stands where smoother
rolls with a smaller gap are used to complete the hot roll process.
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