Energy And Environment
The Energy and Environment work group focused on challenges and opportunities to improve the energy efficiency of forging processes while decreasing their environmental impact in a cost-effective manner. Group members included representatives from forging companies, equipment suppliers, the Forging Industry Association, and the U.S. Department of Energy.
The forging industry of the future will be energy-efficient and will protect the environment. In the next century, the forging plant will be a zero environmental liability, making it a valued and responsible neighbor in its community. To accomplish this, the forging industry must consider ways it can substantially reduce its energy intensity by developing and applying advanced technology. It must examine the industry's current environmental performance and determine how emissions can be reduced using improved technology and practices.
The strategic targets set for the energy and environment areas in the Forging Industry Vision of the Future are shown in Exhibit 4-1.
After some discussion, the group decided to clarify the energy performance targets and expand the environmental targets. The cost consideration was removed from the energy goal, which was rewritten as "Reduce total per-piece energy input/content by 75%." This goal includes the energy requirements of the forging operation itself as well as heat treating, finishing, and other support operations.
Several additional goals have been defined for the environmental area:
Design for safety and the environment
Reduce ambient noise in forge shops to below 85 db
The original goal to eliminate aerosol emissions within forging plants has been expanded to include the use of other toxic materials as well. The goal to recycle all fluids has been expanded to include other byproducts of the forging process. An alternate way of stating this goal is "eliminate wasteful byproducts."
On a cautionary note, the question was raised on the possibility of achieving environmental goals at the expense of the energy goals if some technologies that improve environmental performance require higher energy use.
Barriers to achieving the energy and environmental strategic targets were organized into the categories of financial barriers; process barriers; industry standards; institutional barriers; and materials, resources, and supplies. These barriers are summarized in Exhibit 4-2 and are discussed below.
The nature of the forging industry--the relatively small size of most forging plants, and the cyclic nature of the industry--imposes a number of financial barriers. The most critical barrier identified by the industry is its difficulty in justifying the cost of implementing new, energy-efficient or environmentally benign technologies that may have higher initial costs. The cost of requalifying process changes is also a barrier to adopting new technologies. In addition, the relatively small size of the forging industry makes it difficult for equipment manufacturers to justify developing a new technology. The cost (and availability) of energy is another concern.
Process-related barriers to increasing energy efficiency and reducing environmental impacts of forging cover a broad range of topics, from the forging design process itself to a lack of knowledge about how energy is used in different forging processes. In addition, current forging design processes do not adequately address the environmental issues connected with downstream processing.
In terms of the technologies currently used, the industry has identified limitations in current heating and combustion technologies as a major concern because these processes represent such a large percentage of the industry's total energy (and operating cost) requirements. The length of time that it takes to transfer a part from the furnace to the press adversely affects both energy efficiency and quality. The inability to produce near-net-shape parts prevents the industry from maximizing the yield per part, which results in energy inefficiencies and increased waste. The reliance of many of the industry's secondary processes on toxic materials (e.g., cleaning parts prior to inspection) represents another environmental barrier.
There is a general lack of knowledge about how energy use is distributed among the various process steps used in a forging plant. The electrical losses associated with forging equipment and processes contribute significantly to reduced energy efficiency. There are also problems in adapting technologies from other industries to the forging industry because of differences in the operating environments.
|Exhibit 4-2. Major Technology Barriers to Achieving
Industry Targets in Energy and Environment
( = Most Critical Barriers)
|Financial Barriers||Process Barriers||Industry Standards||Institutional Barriers||Materials, Resources, and Supplies|
|Cost of requalifying process changes
Frugality of forging industry (due to cyclic nature)
Industry too small - not enough market for equipment manufacturers to justify developing new technology
Cost and availability of energy
Cost justification for implementing energy efficient technologies
- environmentally benign technologies
|Maximizing yield per part (near net shape) to reduce energy use
- inability to produce near- net-shape parts
Lack of feedback from operations on how energy use is distributed
Forging design process itself - need to integrate environmental considerations
Limitations in current insulation, heating, and combustion technologies
(heating is largest cost area)
Scale-formation on work piece
Secondary processes which require toxic materials
(e.g., cleaning parts prior to inspection)
Electrical losses in various processes/ equipment
In-process inspection (e.g., hammer) - hard to determine when a part will be completed - if known, could modify process to save energy/reduce scrap
Transfer time from furnace to press - impacts energy/part and quality
Problem with adapting technologies that can co-exist in the forging environment
- technology must be adapted to forging environment
|Do not know baseline energy use/ productivity/ environmental measures
- lack of standard for measuring and benchmarking
Inability to accurately measure the total energy input of a part (heating, forging, heat treat, and etc.)
Inability to revise customers' requirements/ specifications so that industry can use new processes
- especially military
- customer often very rigid
|Management resistance to change
- communication issue - what are you trying to accomplish?
Constant changes in EPA/OSHA definitions, acceptable levels
Lack of industry standards - forging industry does not have good standards
- costs can be prohibitive
Labor opposition/ resistance to technical innovation or change
Resistance to sharing "proprietary" information
Management support of goals and objectives often difficult to achieve (cost?)
Lack of knowledge of potential uses and markets for forging by-products
Too much regulation of utilities
Lack of technical expertise in industry as a whole - needed to adopt/maintain new processes
|Do not have strong enough die materials to eliminate heating
Lack of materials with enough lubricity to eliminate use of lubricants
Inadequate furnace insulation
- equates to heat-up and processing time
Lack of materials knowledge for direct heat-treating after forging
All materials used by industry contain "hazardous" (by EPA definition) elements
- inherently in product, wastes are harmful
Lack of viable non-toxic substitute materials (e.g., environmentally safe quenchant not available
- lack of availability of non-toxic substitutions for insulating materials in furnaces
Lack of available technology for noise control
Lack of environmentally safe lubricants that will not lead to degradation of tool life/production cycle
Another knowledge-related process barrier is the difficulty in determining when a part will be completed. In-process inspection of parts in the hammer or other forging process would enable that process to be modified or even optimized to increase its energy efficiency while reducing scrap generation.
The forging industry is hampered in its efforts to improve its energy and environmental performance by a general lack of knowledge on baseline energy use, waste generation, and productivity measures. The lack of standardized methods for measuring these types of data contributes to this lack of knowledge. A specific example is the inability to accurately measure the total energy input of a part in each process step (e.g., heating, forging, heat treating), which the industry feels is critical to achieving its energy performance targets. The overall lack of industry standards, also identified as one of the most critical barriers, hurts the industry not only in its energy and environmental performance but in terms of quality as well. However, the development of these types of standards would be very costly.
Another standards-related barrier is the forging industry's inability to revise customer requirements and/or specifications (because of customer inflexibility), which would facilitate the industry's use of new processes and technologies. Many customers (particularly the military) are very rigid in their requirements and are not amenable to discussing changes.
The forging industry must deal with numerous institutional barriers, including financial issues and industry standards (both of which have already been discussed), as well as regulatory, personnel, management, and educational issues. Constant changes in EPA and OSHA definitions are seen as a major problem in the industry. For example, guidelines as to what is considered "acceptable" in terms of the amount of an emission or other waste are often revised. Future regulations (particularly on air emissions) may be even tighter. Complying with these regulations (as well as keeping track of changes) is costly and time-consuming. The regulation of various utilities is also considered to impose an energy barrier.
Management support of energy and environmental goals is often difficult to obtain, most likely because of the costs involved. Forging industry management's resistance to change can impede the adoption of new, improved technologies. Part of the problem here is a lack of good communication between management and other personnel in discussing why the change is needed and what it could accomplish. In addition, the plant's labor force is often resistant to technical changes or advancements. There is a lack of technical expertise in the industry as a whole, an expertise that would be needed not only to adopt new technologies and processes but also to maintain them.
The forging industry has not developed sufficient knowledge on the potential uses and markets for various forging byproducts. In this area as well as others, the general industry resistance to sharing "proprietary" information slows the industry's technological advancement.
Materials, Resources, and Supplies
A number of barriers related to the various input materials and resources used by the industry were identified. In terms of the equipment used in forging plants, a lack of sufficient furnace insulation and a lack of available technology for noise control were identified as barriers. Insufficient furnace insulation equates to unacceptably high heat loss, which leads to longer heat-up and processing times. This affects both the industry's energy use and its productivity. The lack of noise control technology prevents the industry from achieving its performance target of reducing plant noise to the OSHA-specified level.
Barriers related to the materials used in forging processes include a lack of die materials that are sufficiently strong to eliminate the need for heating the metal prior to forging. Several materials barriers were identified in the area of lubricants. These include a lack of materials with enough lubricity to eliminate the need for and use of lubricants (identified as a critical barrier), and a lack of environmentally-friendly lubricants that won't lead to degradation of tool life or production cycle. Also of great concern to the industry is the lack of viable environmentally-friendly substitute materials, including quenchants and insulating materials for furnaces. There was also some discussion of how practically all materials used by the forging industry contain "hazardous" elements as defined by EPA. These materials are an inherent part of the process (e.g., chromium and other elements in a steel alloy), yet their wastes are harmful.
The industry also noted that a lack of materials knowledge prevents the industry from heat treating a part directly after it is forged. This could also be considered a process barrier.
A wide range of research and development is needed to overcome existing barriers to achieving the forging industry's energy and environmental goals. These needs are shown in Exhibit 4-3, which presents R&D needs by subject category and distributed by the expected time frame (near, mid, or long) for completion of the research. Near-term activities are expected to yield usable results within the next three years. The results of mid-term activities are expected to be available within a three-to-ten-year timeframe, while long-term activities will provide results ten years from now or later.
Exhibit 4-3 also shows the organization(s) most likely to fund the research. After some discussion, the Energy and Environment Group modified the suggested funding source definitions as follows:
(I) - Industry (forging industry)
(V) - Vendor (equipment/material supplier)
(G) - Government
It was agreed that "funding" would be interpreted to include time and/or equipment, not just actual research dollars. The group felt that very few R&D needs would be funded by a single company, and that most R&D would be collaborative efforts between users, vendors, and the government. Some R&D needs have been given the "G" designation if it was known that a given agency or national laboratory already had access to information that could be used (for example, DOE and NASA already have relevant information on materials and coatings).
Exhibit 4-4 shows the relationships of some key research needs organized to show the relative timing of the R&D efforts. According to this exhibit, the development of consistent measurement standards, improved process monitoring, and new temperature measuring devices would help the industry develop energy and environmental data, as well as material properties and characteristics (e.g., physical flow characteristics). This information would allow the industry to develop models to predict microstructure, optimize furnace heat-up times and develop hybrid heating systems, which would lead to lower energy use.
Reducing the amount of scale generated during forging processes would also improve forging energy efficiency. As shown in Exhibit 4-4, scale reduction could be achieved through the development of heating systems to eliminate scale or the development of pre-coatings to prevent oxidation. Scale reduction would also feed directly into the industry's goal of eliminating byproducts, as would the development of environmentally safe lubricants.
|Exhibit 4-3. Energy and Environment Research Needs
( = Top Priority; = High Priority; = Medium Priority)
(I = Industry, V = Vendor/Supplier, G = Government)
|Time Frame||Process||Recycle/ Reuse||Data and Standards Development||Institutional/ Education||Materials, Resources, and Supplies|
|Hybrid heating systems
- alternate sources of energy (e.g., gas turbine) to power an induction heater to minimize "peak load" penalties
- combination of different types capitalize on advantages
Develop improved die heating and temperature-control systems for hot forging
Optimize heat-up times for forgings (modeling)
Develop improved combustion systems (including burners)
|Develop design standards for equipment used in forging processes
- but not so rigid as to make it hard to industry to move forward
Develop standards for measurement (consistent)
Develop an energy/ environmental profile of the forging industry (baseline data)
Investigate the effect on material properties of heat treating directly after forging
|Develop a systematic, long-range, industry-wide education and training program
Training and awareness for process engineers on design for environment
- integrate environment into the process
Develop apprenticeship programs
Industry/ regulator collaboration in solving environmental problems
|Develop alternative quenchants
Develop environ-mentally safe lubricant
Consolidate forging materials and their applications (would enable you to do better job; would need to educate customers)
|Develop heating systems to eliminate scale
Improved process monitoring techniques (get same/better quality for less energy)
- energy added as a safety factor
Develop induction heating system with higher efficiency (e.g. reshapable coils) or improved materials or insulation
Develop efficient rapid heating systems for different size billets and shapes for low quantity
|Develop new uses/markets for byproducts (e.g., agricultural)
|Energy or force measurement in dies- develop capability
Develop capability to simulate processes (e.g., temperature control) under production conditions
- cooperation between suppliers, end-user, forger, and government
In-process inspection of hot parts - develop technology to do this
Develop flow simulations for microstructure predictions
|New materials to reduce needs for processing
- colder working temperature
- no heat treating
- no conditioning
R&D on surface treatment for die and tooling - lower friction and higher resistance (would lower energy)
Develop new, quick temperature-measure devices (hard to measure with scale) non-contact, optical
|Develop improved metal-handling technologies I/V||Develop material physical flow characteristics (e.g., flow stress) for all specific materials
- each material is different
- for use in simulations (metal flow, die stress)
Develop flow simulations for microstructure predictions
Need to know forging reduction actually required (e.g., hot rolled vs. ingot). Develop actual values of forge reduction
|Develop system to reduce heat loss of billet between furnace and press
Develop improved furnace insulation materials
- more durable, high temperature-resistant
Improve (economic) the quality of starting stock, melt sources (many kinds of steel - EAF, ladle refined): cleaner starting stock gives fewer problems
Improved die materials
- longer life
- low wear
- low cost
- self lubricating
Advanced bar/billet pre-coating to prevent oxidation
- need coatings which could also substitute for lubricants
|Develop slide-in, slide-out dies (like cassette player) that is totally enclosed
Develop alternatives to traditional thermomechanical processing (e.g., magnetic fields, low- or no-gravity methods)
Develop more laser technology for cutting and for heating material (steels)
Develop a new way of heating steel more efficiently
Develop solar powered heating technology; renewable-energy based
|Take waste heat from process or part, store it, use/sell in other applications
Develop waste-heat-to-electricity conversion technology
|Develop a zero-emissivity coating (no radiation, transfer losses)
Develop materials for higher-temperature forging that would take less energy to form while maintaining metallurgical integrity
- develop basic knowledge
- may eliminate process steps
Develop more efficient ways of power transmission
A number of process-related research and development needs have been identified for each of the three time frames. In the near term, the development of modeling capability to optimize forging heat-up times was suggested, as was the development of improved die heating and temperature control systems for hot forging. Hybrid heating systems, whose development would most likely involve the forging industry and vendors, were identified as a fairly high-priority research area. These technologies would combine different types of heating systems to capitalize on the advantages of each (e.g., using alternate electricity sources to power an induction heater).
The development of alternative heating systems that eliminate scale (leading to improved environmental and energy performance as well as improved quality and productivity) has been identified as a high-priority, mid-term research need that would require the involvement of industry, vendors, and government. Of even higher priority (actually the highest priority need identified by the Energy and Environment Group) is the development of improved process monitoring techniques that would allow forgers to maintain or improve quality while using less energy, also a mid-term effort involving forgers, vendors, and government. Currently, extra energy is consumed (in the form of longer processing times, higher temperatures, etc.) as a process safety factor to ensure adequate heating of materials for forging. The industry also needs advanced induction heating systems with higher efficiencies, which could be achieved through the use of improved insulation or other materials, or possibly through the use of reshapable coils.
All of the long-term research needs identified by the industry would require government involvement. These include the development of new ways of heating steel more efficiently, the development of more laser technology for cutting and for heating, and the development of alternatives to traditional thermomechanical processing methods (for example, low- or no-gravity methods or ones utilizing magnetic fields.)
Another long-term research need is the development of renewable-energy-based heating technology (solar-powered, for example). A final idea is to develop totally enclosed, slide-in/slide-out die systems that would reduce emissions, noise, and heat loss.
A total of three R&D needs related to recycling/reusing materials and waste heat have been identified. The development of new uses and markets for forging byproducts (particularly scale) is a mid-term need that would require the cooperation of industry, vendors, and government. Agricultural applications may present one new area of opportunity.
Two long-term needs focusing on the recovery and reuse of waste heat were discussed. The first, which is considered fairly high priority, is to develop the capability to take waste heat from a process or part, possibly store it, and use or sell it in other applications. A second idea is to develop technologies to convert waste heat to electricity.
Data and Standards Development
As discussed in the barriers section, the lack of good industry standards and accurate measurement of key variables hurts the industry's energy and environmental performance as well as quality, and productivity. The industry has identified a number of research and development needs addressing these issues. In the near term, the industry (working with equipment vendors) could develop design standards for the equipment used in forging processes. In cooperation with the government, they could develop consistent standards to be used in measuring various parameters. Another effort requiring the involvement of industry, vendors, and government would be to investigate the effect on material properties of heat treating directly after forging.
A very high-priority need is the development of a superior base of data and information on the energy and environmental aspects of forging processes. This would include the energy content and requirements of the part during each step in the process. This data could be collected using new sensors and control technology and improved process monitoring techniques (discussed in other subsections). Ultimately, the data could be used to optimize furnace heat-up times and otherwise improve process energy efficiency.
A total of six mid-term R&D needs are identified in the area of data and standards development. The highest priority need is to develop materials physical flow characteristics (e.g., flow stress) for all of the materials used in forging. This data could then be used as input to simulation models for metal flow, die stress, and other key phenomena. A related R&D need is the development of a flow simulation model for microstructure prediction.
The industry has identified the development of the capability to simulate processes (including temperature control) under actual production conditions as a fairly high-priority need that could be addressed by the industry and its vendors working together. Working with the government, forgers and vendors should develop the capability to measure the energy or force used in dies. These three could also work cooperatively to develop actual values of forge reduction (the reduction actually required) for various inputs and conditions (e.g., hot rolled versus ingot). The development of technology to perform in-process inspection of hot parts is another priority need.
A number of near-term activities have been suggested to help the industry overcome the institutional and educational barriers described previously. The highest priority activity is to develop more structured education, including more intense training opportunities. Apprenticeship programs were discussed as one possible solution. The industry's process engineers also need more training on and awareness of the principles of "designing for the environment."
Materials, Resources, and Supplies
The research needed to overcome the barriers in the materials, resources, and supplies area were distributed among all three time frames. In the near term, the development of environmentally safe lubricants is noted as being a fairly high priority need. These lubricants, as well as alternative quenchants, are felt to be good development efforts for the industry and its suppliers to work on together. Government involvement would probably be required in a proposed effort to consolidate forging materials and their applications, an effort that would require considerable customer education. Reducing the very large number of alloys currently used (many of which could be substituted for others with no degradation of performance) would allow the industry to concentrate its data development efforts, allowing better control of materials properties and forging processes.
A large number of R&D needs are proposed for the mid term. The highest priority need identified in the mid term--develop improved die materials--is also the second-highest priority need for the Energy and Environment Group. Improved die materials would have longer life and would be low-cost, low-wear, and self-lubricating (eliminating the need for lubricants). Another high-priority need in this area is the development of pre-coating to prevent oxidation (scale formation).
The development of new materials to reduce the need for processing is also given high priority. The goal would be to develop materials that could be used with colder working temperatures and/or would eliminate the need for heat treating or conditioning.
Also in the mid term, industry and government could team on finding a way to reduce heat loss from the billet between the furnace and the press. This could even include the development of a coating to put on the billet after it exits the furnace. Another suggested activity is R&D on surface treatments for dies and tooling that would reduce friction, thus saving energy.
The development of new, fast, temperature-measurement devices (non-contact optical devices) that would overcome the problems of measuring temperature when scale is present is a mid-term research activity appropriate for the forging industry and its equipment suppliers. A proposed vendor/government activity is the development of improved furnace insulation materials that are more durable and more resistant to higher temperatures.
Three long-term ideas have been suggested in the area of materials, resources, and supplies, ideas that would require government involvement. The highest priority item is the development of more efficient power transmission technologies. Another idea is the development of a zero-emissivity coating that would have no radiation or transfer losses, thus reducing heat losses. Finally, the industry proposes investigating the development of materials for higher-temperature forging that would take less energy to form (and possibly reduce the number of process steps) while maintaining metallurgical integrity.