8
HEAT TREATING
The Bar Finishing facility is equipped with five Sauder Energy Car
Bottom furnaces. There is one high temperature furnace capable of
reaching 2100°F, while the others are capable of reaching 1800°F. The
furnaces are limited to a maximum bar length of 33 feet. The quench
tank has a 30,000 gallon capacity and is capable of providing agitation
and temperature control. Water is the only quench media used at the
Bar Finishing facility. The minimum bar diameter that can be quenched
is 2.5 inches.
BAR INSPECTION
There are two inspection lines at the Bar Finishing facility, a small bar
inspection line (SBIL) and a large bar inspection line (LBIL). The SBIL can
accommodate round bars ranging in diameter from one to five inches
while the LBIL can accommodate round bars from 2.5 to 9 inches and
round cornered squares from 2.5 to 8 inches. Both lines can
accommodate bar lengths of 15 to 45 feet.
At the SBIL, bars are rotary straightened and chamfered prior to
inspection. Surface inspection is performed via a Forester Magnetic
Flux Leakage unit, capable of 100% surface coverage with seam
detection of 0.3 mm for smaller bars and 0.5 mm for larger bars.
Ultrasonic inspection is performed via a rotary immersion UT inspection
unit, capable of 100% volumetric coverage using normal incidence and
shear waves. Ultrasonic inspection is capable of detecting 1mm wide
defects. The SBIL is also equipped with a 100% Eddy Current grade
verification coil.
On the LBIL, bars are shot blasted and pass through an Eddy Current
grade verification coil. Surface inspection is performed via an Eddy
Current surface inspection unit, capable of 100% surface coverage with
seam detection of 0.5mm. Ultrasonic inspection is performed via a
Magnetic Analysis Corp 48 channel transducer with four fixed heads,
capable of 100% volumetric coverage. Ultrasonic inspection is capable
of detecting 1mm wide defects.
