Maintaining precision alignments in steel plants has
never been easy. Typical methods include optical telescopes and alignment
templates for use with feeler gauges. These methods are very time consuming
and are susceptible to significant errors, which is very important as
Dave Spinelli, Team Leader, Dofasco, Inc. explains:
"Maintaining segment roll alignment
and profile to a high degree of precision is critical to production
of defect-free continuously cast slabs." [Source: AISE
Steel Technology, January 2002, PDF, 338K]
Our lasers offer the precision and timesavings to
meet the ever-tightening tolerances of the steel industry. Our L-743 Ultra-Precision
Triple Scan( Roll Alignment System is one of only 2 lasers in the world
(L-733 is the other) to offer 3 automatically rotating laser planes, which
creates a powerful tool to not only MEASURE but also FIX almost any misalignment
problem in continuous caster mills.
The results can be impressive as Mr. Spinelli continues,
"[Using lasers, Dofasco has] achieved significant
segment repair cost and time savings and has resulted in increased segment
life and improved as-cast slab quality."
[Source: AISE
Steel Technology, January 2002, PDF, 338K]
Set Roll Pass Line Faster with Fewer Technicians
One of the more time-consuming tasks in maintaining continuous-caster
steel mills is setting the correct caster roll pass line. Unlike using
optics that requires at least 2 operators, the L-743 only requires 1 operator,
and since the laser automatically sweeps a reference plane, it is a very
simple process to measure and set the heights of a caster segment rolls.
The heights can be set using precision inserts with our targets, as the
tolerance of the centerline of the target to its base has been accurately
controlled.
Another timesavings feature of the L-743 is that all the rolls of a segment
can be checked from one setup and the operator who set the laser up can
start doing the measurements himself! Furthermore, the laser can be setup
between 2 segments and both of them can be checked at the same time from
the same setup!
Easy Squareness and Plumb Measurements for Segment Pins
The L-743 has 3 automatically sweeping laser planes, one horizontal and
2 vertical, which are all square to each other to within 1 arc second
(0.00006"/ft or 0.005 mm/M). This means that complex tasks like checking
the squareness of the pins to the face of the caster is an easy job for
the L-743. This greatly reduces the setups needed to measure squareness
when using optics. The L-743 can also be used to easily check the plumbness
of the segment pins in the mill itself, as the vertical laser planes have
100 feet (30.5 meters) radius and are plumb when the laser is leveled.
Multiple Targets and Laser Planes Reduces Downtime
With multiple laser planes and multiple targets, the L-743 can take the
place of at least 2 sets of optics. Once the laser is setup, multiple
technicians can each use a target to realign the mill during planned or
unplanned outages. This can save tremendous amounts of time and can bring
the mill up that much sooner.
Less Manpower Needed for Alignments
The L-743 Roll Alignment System reduces alignment
manpower. Wireless targets and automatically rotating laser planes make
setting up the laser at each machine section a one-man job, freeing up
technicians for other critical work during shut downs. The wireless readout
displays both reference/benchmark targets simultaneously, allowing the
operator to quickly buck-in to the benchmarks. Traditional optics usually
require at least two men to work the instrument.
Laser Technology Reduces Optics' Variability Between Alignment Crews
PSDs, or position sensing detectors, are one of the critical components
of our laser alignment systems. It is this PSD that senses the laser beam
and turns it into a digital signal. This greatly reduces the man-to-man
variability found in optical measurements because sophisticated electronics
determine the measurement rather than the human eye.
Anyone with optical experience knows that the quality of the measurement
depends on having the same experienced person perform the entire alignment,
which can create big problems when the job takes more than one shift to
complete. By relying on the PSD to produce highly repeatable measurements,
our L-743 makes it much easier to hand off an alignment project from one
crew to the next. This greatly reduces the need to have new crews backshoot
the previous crews' work to "calibrate" to their readings.
No Need for Optics' Recalibration After Plumb Measurements
Unlike some optics that usually require time-consuming recalibration of
the levels each time plumb is checked, the L-743 can simultaneously check
level and plumb from a single setup. This is because the squareness measuring
capability is built into the instrument. Furthermore, the levels usually
only require calibration once a month, not every time you use it!
Laser Planes Have 200' Range
One of the most powerful features of the L-743 is the automatically rotating
laser plane with a range of 100 feet (30.5 meters) in radius. That means
the horizontal parallelism of rolls at almost any elevation can be measured
simultaneously without having to move the laser vertically. This also
allows the laser to be moved to more sections without having to change
the location of the reference targets.
Competitive Laser Systems Use 10-Year Old Technology
Our competitors' roll alignment lasers use point-and-shoot laser technology,
along with remote beam-bending devices that are difficult to set up and
re-locate. We abandoned that laser technology 10 years ago with the introduction
of our multi-plane, continuously rotating lasers. Not only is this point-and-shoot
technology difficult to set up, it also requires extra manpower and about
50% to 70% more time.
Wireless Targets and Readouts
With Hamar's new line of wireless targets (A-1531, A-1532 and A-1533)
there is no need to string long extension cords to reference. These targets
have a resolution of 0.001" (0.02 mm) and built-in readouts. With up to
3" of measuring range and height gage measuring capabilities, they are
perfect for most steel mill alignment applications.
For higher accuracy applications, our second new line of wireless targets
(A-1519, A-1519HR and A-1520) is an ideal alternative. The targets have
up to a 1" (25 mm) measuring range, resolutions as low as 0.00002" (0.0005
mm) and can be used up to 100 feet (30.5 meters) from the readout (R-1309),
which uses a Cassiopeia PDA, color software and a wireless receiver to
display up to four targets simultaneously.
Software Quickly Collects and Analyzes Data
The L-719 can also be linked to our new Plane 5 flatness analyzing software.
It is a Windows 95/98 based software that can quickly analyze almost any
layout for flatness or straightness. Plane 5 will even analyze squareness
if used with our squareness lasers (L-743, L-742, L-741, L-733, L-732
& L-731). Squares, rectangles, frames, circles, rings, and up to four
sets of ways can all be easily analyzed with Plane5. The alignment data
is automatically downloaded by using our wireless data receiver, the A-908.
