Implementation of Metal Casting Best Practices - EERE - U.S. ...

Automated Molding Line
Steel Foundry-1 has installed an automated molding line that utilizes chemically bonded sand
and produces flaskless molds. This state-of-the-art system includes sand preparation and mixing
equipment, a fast loop molding compaction system, automated rollover/draw machine, waterbased
coating and drying equipment, and two automatic mold-closing machines. This system has
the ability to produce molds at a rate of 10 per hour using the latest process controls.
This system is unique for a steel foundry. It enables the foundry to not only increase productivity
but also reduce the scrap rate. It gave the foundry the ability to keep up with one of its
customer’s high demand without experiencing a disproportionate rise in its labor costs. In
addition, because each mold is constructed under computer-monitored and computer-controlled
steps, molds are formed under the same conditions, thereby ensuring consistency among molds.
This automated system was a large capital investment for the facility, yet it has paid off by
allowing the plant to retain an existing customer and to expand the volume of production for that
customer at a reasonable cost.
2. Areas of Improvement
Even as proactive as Steel Foundry-1 is in using state-of-the-art technologies and techniques,
there are still areas in which the foundry can further reduce its costs and energy consumption.
The assessment team identified areas of opportunity where the plant can make changes, in many
cases with very little investment. Many of the suggestions made involve simple steps that quite
commonly are overlooked by steel casters because plant personnel are more concerned about
getting castings delivered on time.
Compressed Air
Steel Foundry-1 has the potential to save thousands of dollars in energy costs by improving and
optimizing its compressed air system. Many of the fixes could take place with little or no capital
investment. For example, like many foundries, Steel Foundry-1 could implement some easy
steps to reduce the number of compressed air leaks. The assessment team noted a number of
leaks during the foundry tour. A single 1/16-inch diameter air leak can cost about $200 per year.
The assessment team recommended that the foundry have a team of employees tag and repair
existing air leaks over a weekend when peripheral noise from daily production will not interfere
with the leak detection. Furthermore, the assessment team recommended that the facility should
note the weekend horsepower used to maintain pressure in the line. This will provide input as to
the quantity of air leaks and the equipment that is using non-essential air. The facility should
identify and isolate any equipment that has non-operating air requirements.
Steel Foundry-1 could also improve its energy efficiency by utilizing the most efficient
compressed air tools available. Currently, the facility utilizes air-powered stirrers in its coatings
tanks. These stirrers use approximately four times the amount of energy as do electric stirrers.
The assessment team recommended that the facility replace its air-powered stirrers with electric
stirrers and estimated that the pay back for this replacement would occur in less than 2 years.
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