ITP Metal Casting: Advanced Melting Technologies: Energy Saving ...

necessary to impart the mechanical properties the casting facility desires. Furthermore, the
temperature requirements vary for each alloy/metal melted in the furnace. Therefore, the concept
of a single melting technology that can crosscut the entire metal casting industry is unreasonable.
Advances along multiple pathways are required that suit the needs of different casting facilities
for achieving significant energy savings in the overall melting process.
Batch-Melting Schedule
The scheduling of melting is traditionally determined by the casting requirements of the metal
casting facility. Most casting facilities melt in batches, in which case, the facilities tend to
schedule to melt at certain hours of the day on certain days of the week. This practice requires
frequent starting and idling of
the melting equipment, thus reducing the efficiency of the
operation. In addition, many metal casters produce variable-sized heats, which require the
operation of several different-sized furnaces and involve heating many cold furnaces, a factor
that further reduces the energy efficiency of melting. The inconsistent heat sizes also increase
the
maintenance cost because of the stress imposed on the furnace refractory from the significant
swings in the temperature.
Requirement of New Permits
New furnace technologies, particularly those that require new or expanded exhaust systems,
frequently require local and state permits. Obtaining these permits incur financial costs and
require valuable personnel time.
Many small metal casters find it difficult to allocate these
resources for acquiring permits when
implementing new technologies at their foundries.
Advanced melting technologies that can be retrofitted onto the existing equipment without any
need for new permits are, as a result, more likely to be adopted by the industry.
6. Future Direction of Research: Potential Energy-Saving
Technologies
The following recommendations for R&D offer the most promising opportunities for decreasing
energy consumption in melting operations in the metal casting industry.
Retrofit Technologies Database
Tool
Considering the diversity of the U.S. metal casting operations and their limited resources,
possibly the most advantageous path for introducing energy-efficient melting technologies is to
develop a web-based database tool of available retrofit technologies. This tool will enable metal
casters to compare and weigh their options when evaluating the new melting technologies. The
casters must be able to input their furnace type, scheduling, alloy, and tonnage requirements. The
tool could then output various retrofit technology options or a combination of options that can
meet their production demands, along with pros and cons of each option. The tool should also
provide rough estimates of the implementation cost and fine-tune the potential of each retrofit
technology, along with the estimated energy and cost savings. Such a tool would assist the metal
casting industry in making educated and nonbiased decisions on how to improve their foundries’
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