The Acquisition of Modern Aluminum Extrusion Systems
Part 2: Conception
Definition: What remains in the
mind as the product of careful mental activity.
Key Words: Recognition, understanding.
by Roger A.P. Fielding, BENCHMARKS
The first article in the “Acquisition
of Modern Aluminum Extrusion Systems” series presented the rationale
for modernizing an aluminum extrusion plant. Entitled Motivation,
the article introduced profit as the prime force driving change. Measured
by reduced conversion costs, profits result from shorter lead times,
improved productivity, and enhanced recovery. Additionally, the intrinsic
safety and reduced emissions from state-of-the-art equipment ensure
that one can stay in business.
This insight into motivation is a product of the Aluminum Extruders’
Council International Technology Exchange Tour of Europe in 1995,
later reported in Light Metal Age. Tour participants observed what
some of the leading European extruders were doing to modernize their
plants. Light Metal Age reported that:
• 90% of the extrusion presses visited were fitted with hot
log shears;
• 50% had multiple pullers;
• 60% featured automated handling systems; and,
• 75% had stackers at the finish cut saw.
Why was this equipment acquired? What does each part of a modern
aluminum extrusion system contribute to maximizing profit? The chart
at right illustrates.
Integration of extrusion equipment into an automated system brings
other benefits. To maximize their effectiveness, aluminum logs must
be of consistently high quality, and extrusion dies must work every
time. The metallurgical structure and properties of the aluminum must
be consistent from log to log and from billet to billet. The die must
go to the press and deliver the required quantity and quality of extrusions
at the desired speed. The drive to increase profits through mechanization
and automation, evident in the report on the visits to European extrusion
operations, requires reliable equipment and consistently high quality
inputs of aluminum log and extrusion dies to be effective. Productivity
and quality improve; conversion costs are reduced.
Perhaps as important as the direct benefits of each piece of equipment
is the comprehensive advantage of an integrated system. The downtime
of an extrusion press system consisting of log or billet racks, furnace,
hot shear, press and runout, pullers, cooling table, stretcher, batching
table and feed conveyors, saw table (with its feed conveyors), saw,
and stackers will be dependent on the reliability of each of the component
parts. While a reliability of 99% may have been acceptable when presses
extruded onto a fixed runout table with little or no additional handling,
it is totally unacceptable for a component in an integrated system.
The reliability of the aluminum extrusion system is the product of
the reliability of each of the component parts. If each of the sub-systems
listed above were only 99% reliable, the system would be “down”
12% of the time!
To reduce conversion costs, quality — in its broadest sense
— must be improved. The inputs of log and dies must meet performance
specifications. Billets must be heated to correct temperatures in
minimum time. The extrusion press and the extrusion system of runout,
pullers, handling system and stretcher, saw table, finish cut saw,
stackers, and aging ovens must operate properly with minimum down
time.This is only possible with engineered extrusion systems operated
by skilled people using inputs of consistently high quality. As quality
is the means, reduced manufacturing lead time is the measure of performance.
Reduced conversion costs and increased profits are the result.
The Acquisition of Modern Aluminum Extrusion
Systems - Part 3
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