Solar Atmospheres of Western PA recently commissioned their third car bottom air furnace. This Class 2 air furnace has a maximum operating temperature of 1350°F measures 60” wide x 38” high x 168” deep.
The newly installed equipment, manufactured by Heat Treat Equipment Inc., joins two other HTE car bottom furnaces that are 14’ long and 20’ long respectively.
“After successfully hardening in vacuum at 1850°F +/- 10°F, the fully hardened die was transferred to the air car bottom furnace for the triple temper operation of 1025°F +/- 10°F.” – Bob Hill, President, Solar Atmospheres WPA and Michigan Source: Solar AtmospheresRobert (Bob) Hill, FASM President Solar Atmospheres of Western PA Source: Solar Atmospheres
Bob Hill, president of Solar Atmospheres of Western PA and Michigan, states, “the addition of this large air tempering/aging equipment compliments our five (5) state of the art vacuum car bottom furnaces very nicely. Instead of hardening and triple tempering this 6000 pound H13 die exclusively in a vacuum environment, Solar can save our customers and our company over 100 hours of valuable and expensive vacuum processing time.”
He continues, “After successfully hardening in vacuum at 1850°F +/- 10°F, the fully hardened die was transferred to the air car bottom furnace for the triple temper operation of 1025°F +/- 10°F. These large and uniform car bottom furnaces are a win/win for both the customer and for production — not exclusively for heavy parts, but also when treating long components.”
This press release is available in its original form here.
Now that a new year is in full swing, it may be time to consider that all of the heat treating equipment that’s currently in the workplace has aged along with us. Without proper maintenance in place, you may start to see signs of age, wear, and tear on the high output furnaces that this industry relies on.
This Technical Tuesday,was originally published inHeat Treat Today’sJanuary/February 2024 Air and AtmosphereHeat Treatprint edition.
Jacob Laird Mechanical Engineer Premier Furnace Specialists, Inc./BeaverMatic Source: Premier Furnace Specialists, Inc./BeaverMatic
Most companies have a “workhorse” furnace which is run exhaustively, and even new furnaces that run this way can start looking quite worn after just months of use. Yet decades-old equipment remains in regular use across the country, thanks to knowledgeable maintenance personnel. Since there is somewhat of a void in personnel for this position, here are a few ways to make sure your furnaces keep running into old age.
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For roller hearth or belt furnaces with rollers, there can be an extensive number of points in the drive which may facilitate misalignment. Most maintenance crews know to keep chains and sprockets in alignment and to keep bearings well-greased to avoid seizing, but these may not be enough for the high temperatures at which these furnaces typically run. Even though they are turning at slow speeds, the roller’s bearings should be filled with high-temperature grease which is designed not to break down and leak despite the heat constantly being transferred through the roller to the external trunnions (shaft ends). If the bearing already has standard grade grease, it needs to be fully pumped out of the bearing with new high-temperature grease to avoid contamination or reactions between the two which could cause leaking or seizing.
Roller hearth furnace system
For driven rollers, it’s only necessary to “lock-down” the drive side of the roller’s components using cone or dog point set screws (sometimes both) and thread locking compounds. As the furnace heats up, the rollers will expand. By leaving the idle end “free,” it allows a path of least resistance for growth, which allows for the best chance to keep drive mechanisms in-line.
An infrared (IR) thermometer can be a useful tool for diagnosing heat leaks around any furnace and avoiding burns while doing so during operation. It’s important to note that on stainless steel components and the glossy enamel coatings on some furnaces, IR temperature readings likely will not be exact. Quality IR thermometers have adjustable emissivity settings which greatly reduce the error caused by these highly reflective surfaces, but readings still should be used simply as reference points.
FCE insulation
It’s a good idea to occasionally check the furnace case for “hot spots,” and this tool allows it to be done without much effort. These are areas which have a higher than typical temperature compared to the rest of the furnace. This can be one of the earliest signs that insulation quality in that spot has issues. The insulation can be checked and repaired rather than waiting until the furnace’s case steel begins to turn white and burn away, leading to more costly repairs. For brick-lined furnaces in particular, one ideal time to perform this check is during the lengthy dry-out procedure to ramp up to operating temperature after a shutdown. The idle time at low temperatures helps to catch issues before high operating temperatures quickly make them worse. For roller hearth furnaces, simply checking the average temperature of each roller’s exposed trunnions and bearing housings can give insight into potential future issues if individual rollers run hotter than others.
As they say, “The best time to start was yesterday. The next best time is now.” Even a furnace that has seen better days can be maintained, repaired, or rebuilt to keep operations running smoothly and, most importantly, safely.
About the Author
Jacob Laird is a mechanical engineer at Premier Furnace Specialists. Jacob has a BS in both mechanical engineering and physics from South Dakota State University. Among many other things, Jacob is known for his skills in sizing/design of combustion systems, burner assembly, and electrical heating systems.
A supplier to the railway industry has ordered a technological line consisting of two vacuum furnaces, three tempering furnaces, and two washers. The line will be utilized for hardening processes of steel parts used in railway rolling stock.
The SECO/WARWICK line for voestalpine Fastening Systems consists of an electric chamber furnace, a washer, a cooling station, and an endothermic atmosphere generator. The hardening process will be carried out in a controlled atmosphere with temperatures up to 1742°F.
Additionally, the technological line includes an electric chamber furnace designed for the heat treatment of steel parts in a protective nitrogen atmosphere at temperatures up to 1292°F, along with a washer, cooling station and endothermic generator. The line will include a loader operating in automatic mode, a set of roller tables and a closed loop water system. The number of the supplied technological line units is selected to ensure the quality of manufactured components.
Mariusz Raszewski, Deputy Director of the Aluminum Process and CAB Furnaces Team, SECO/WARWICK (Source: SECO/WARWICK)
Mariusz Raszewski, deputy director of the Aluminum Process and CAB Furnaces Team at SECO/WARWICK said, “The line is configured in such a way that if the volume of the company products decreases, the customer can also offer commercial processing due to the wide technological spectrum of this main furnace unit.”
The whole solution will be supervised by a master system, which is used for the continuous monitoring of the heat treatment equipment operation and provides advanced data analysis for the production processes.
Mariusz Fogtman, COO, voestalpine Fastening Systems (Source: voestalpine Fastening Systems)
“The universal furnace solution will allow [us] to process details in various configurations,” Mariusz Fogtman, COO of voestalpine Fastening Systems commented. “Apart from technological parameters, it is important for us to limit the processed details’ deformations, which is possible in the ordered solution. SECO/WARWICK presented a partnership and flexible approach to the challenge of this order”
This press release is available in its original form here.
Kittyhawk, Inc., backed by the Dallas-based private equity firm Trive Capital, has acquired Stack HIP, LLC from Stack Metallurgical Group (SMG). The acquisition represents a significant expansion of capacity and capabilities in hot isostatic pressing (HIP) for aerospace, space, defense, and medical applications.
Operating from its facility in Albany, OR, Stack HIP provides HIP services to aerospace, defense, and medical clients by operating the largest high-pressure HIP vessels in North America. This enables them to process large, complex castings and additively manufactured metallic parts. Post-closing, SMG will continue to operate its classical heat treatment and aluminum special processing facilities in Portland, OR, Spokane, WA, and Salt Lake City, UT.
Brandon Creason President Kittyhawk
“We’re excited to welcome Stack HIP customers, employees, and suppliers into the Kittyhawk family,” said BrandonCreason, president of Kittyhawk. “Stack HIP will allow Kittyhawk to service mission critical parts up to 63” in diameter, enabling us to process the full array of components for our customers. At Kittyhawk, we commit every day to providing the best service and quality to our customers, and we’re thrilled to now do that with the added capabilities and dedicated employees of Stack HIP.”
Doug Puerta CEO Stack Metallurgical Group
Doug Puerta, CEO of SMG commented, “We look forward to continued collaboration with Kittyhawk to deliver a differentiated level of service, quality, and value to our shared customers. This transaction will allow both companies to further drive capacity, quality, and capabilities in our respective services to best serve the PNW market.”
“This is an important step in growing the platform specialized in this highly-differentiated HIP capability. [Kittyhawk] continues to benefit from strong industry tailwinds, and we are excited to support our customers by investing in capacity,” said David Stinnett, partner at Trive.
This press release is available in its original form upon request.
Roller hearth furnaces are known as the work horses of the heat treating industry. Though they may be common, these furnaces still hold some surprises — namely, their diverse applications, potential to be fully automated, and long life span. Five industry leaders provide insight into the current furnace features and how to optimize them for annealing heat treat. As you read, notice the different emphases each expert addresses.
This Technical Tuesday was originally published inHeat Treat Today’sJanuary/February 2024 Air and AtmosphereHeat Treatprint edition.
Application Determines Customizable Furnace Features
This type of furnace is highly customizable, and, as Tim Donofrio, VP of Sales at Can-Eng Furnaces International explains, knowing the application will determine furnace features.
What Features Do You Offer on Your Roller Hearth Furnace for Annealing Various Materials?
Tim Donofrio Vice President of Sales Can-Eng Furnaces International, Ltd. Source: Can-Eng Furnaces International, Ltd.
The following is based on roller hearth furnaces operating at or above 1400°F.
Annealing furnace features depend upon the material being processed and the metallurgical process being carried out. They can be provided with a wide variety of features for preheating, annealing, slow cooling, oxidizing or bluing and accelerated cooling.
Preheating features include direct or indirect heating applications, under air or controlled atmospheres. Preheating in some cases requires features for burn-off of residual blanking fluids prior to entry into the critical anneal chamber and as such, the off -gas must be appropriately addressed.
Annealing can be a direct or indirect heating application using natural gas, blended hydrogen/natural gas, and electrical energy sources. Process protective atmospheres include N2, Exothermic gas, Endothermic gas, N2 + H2, and H2. In some cases, process atmospheres must be carefully controlled and monitored to very low O2 PPM levels to ensure correct oxides are formed or, alternatively, a bright oxide-free finish is achieved, something very critical when annealing electrical steels for transformer core and motor annealing. Today we see a rise in the use of roller hearth furnaces for the manufacture of transformer core and motor cores, processing electrical steels and amorphous metals. This is largely a result of the electrification of the world.
Post-annealing cooling and bluing are paramount to the process success. In most cases, cooling and soaking stages are provided through the integration of direct and indirect cooling methods that include air, water, and externally chilled atmospheres that can be directly injected into the furnace system and recirculated.
How Is Your Roller Hearth System Unique?
Roller hearth furnaces are the work horse of the industry; they are used for a variety of other heat treating applications. For example, roller hearth furnaces can also be used for low temperature curing, tempering, and aluminum heat treating applications. These lower-temperature roller hearth furnaces do not operate above 1400°F and are built with different fabrication and refractory standards. Of course, additional high temperature applications include neutral hardening, case hardening, carbonitriding, isothermal, and spheroidizing annealing and normalizing.
Roller hearth furnace
Can-Eng Furnaces International offers roller hearth annealing furnaces that meet the stringent demands of today’s manufacturers where safety, product quality, and equipment reliability are at the top of our engineers’ minds during design and development. Can-Eng has developed a strong user base that has benefited from design features that ensure tight temperature control and repeatable thermal profiles while also tightly controlling process atmospheres. This is achieved by integrating some of the best available heating and atmosphere technologies while being combined with state-of-the art automation and robotics to deliver the lowest cost of ownership processing systems to our clients.
What Are Best Practices for Training In-House Operators on Roller Hearth Annealing?
Our company promotes hands-on and classroom multi-level training of operators, maintenance staff, and engineers. This provides a complete and full understanding of the equipment and the opportunity to train within the company for future talent development.
What Are the Furnace’s Operational Advantages?
Can-Eng integrates operator-friendly features that contribute to the reduction in energy and atmosphere consumption while minimizing the carbon footprint and emission levels. Combined with on-board system diagnostics, monitoring, and data collection, these allow for minimal operator involvement.
What Is the Most Common Heating Method?
Today, the most common methods are both natural gas and electric. However, Can- Eng works to integrate features that provide our partners with the benefits of reusing waste heat sources such as flue gases within the system or facility to improve operating efficiencies.
What Are the Challenges in Operating This Type of Furnace?
These (atmosphere control, maintenance, uptime, and temperature control) are all typical challenges that are addressed in design. The key is to design flexibility, ease of use, and operator-friendly features to avoid problems in the future when the client wants to process different products in a different way.
Training and Maintenance To Optimize Uptime
Bob Brock, sales engineer at AFC-Holcroft, emphasizes the importance of training and maintenance to best operate the roller hearth system.
What Features Do You Offer on Your Roller Hearth Furnace for Annealing Various Materials?
Bob Brock, Sales Engineer, AFC-Holcroft
Roller hearth furnaces are designed to provide greater uptime, ease of maintenance, and trouble-free operation and are always custom-designed to meet our clients’ specific processing requirements.
Modular designs are available to accomplish basic heating, holding, and cooling segments but also to incorporate burn off, cyclic spheroidizing, bluing, fast cooling, and blast cooling under controlled atmospheres ranging from Endothermic to Exothermic gases, nitrogen, hydrogen, and products of combustion. A broad range of material handling automation and control platforms providing total data monitoring, controlling, tracking, and acquisition capability are also offered.
How Is Your Roller Hearth System Unique?
AFC-Holcroft has designed, built, and commissioned hundreds of roller hearth manufacturing, and fi eld support teams have extensive knowledge and experience with annealing, isothermal annealing, normalizing, carburizing, and solution and aging processes for ferrous and nonferrous applications. This expertise has well positioned us in the roller hearth furnace market.
What Are Best Practices for Training In-House Operators on Roller Hearth Annealing?
3D image of annealing roller hearth furnace Source: AFC-Holcroft
We use a two-step approach when training operators on our equipment. First, hands-on training provides the best opportunity to learn equipment operation, startup and shutdown procedures, as well as maintenance tasks. Second, we follow up hands-on training with classroom discussions to further the operator’s knowledge of equipment and the use of our operating manual. Our two-step approach arms our client operational team with the confidence and knowledge they need to be successful from day one.
What Are the Furnace’s Operational Advantages?
Roller hearth furnaces are designed and built with longevity and uptime in mind. From our integrated preventative maintenance reminders, robust construction, and user-friendly controls, it’s not uncommon to see our equipment still in operation for 50 years or longer.
What Is the Most Common Heating Method?
Natural gas continues to be the predominate heating source in North America, although we have seen an increased interest for alternate heating sources like electric, hydrogen, and bio over the last several years. We anticipate this trend to continue as companies invest in minimizing their carbon footprint, and can provide clients with carbon footprint analysis and operational costs on our equipment.
What Are the Challenges in Operating This Type of Furnace?
Routine equipment maintenance is key to operational uptime. AFC-Holcroft offers a wide range of preventative maintenance programs for our clients. The services can be customized to include hot and cold inspections, thermal imaging, burner tuning, and equipment optimization analysis.
Consistency Is Key To Increase Furnace Life
Given that the roller hearth furnace is a continuous system, understanding how the system works and operating at the correct, consistent rate is crucial for success. Jacob Laird, mechanical engineer at Premier Furnace Specialists, dives in deeper.
What Features Do You Offer on Your Roller Hearth Furnace for Annealing Various Materials?
Premier Furnace Specialists (PFS) is capable of building annealing furnaces for a wide range of workloads. We have built small batch normalizing furnaces with simple manual roller hearths, as well as 120+ foot long fully automated annealing roller hearths with multi-zone control and automatic load staging. We also offer a variety of controlled heating/cooling systems and atmosphere generators and gas dryers to provide optimal annealed part quality. Controlled cooling systems may include: radiant tube indirect cooling, atmosphere forced convective cooling, and post-process forced convective cooling with ambient air.
How Is Your Roller Hearth System Unique?
Jacob Laird Mechanical Engineer Premier Furnace Specialists, Inc./BeaverMatic Source: Premier Furnace Specialists, Inc./BeaverMatic
One of the unique uses for annealing furnaces is for soft magnetic steel alloys aft er they have been cold worked or formed. This is often used for products inside electrical equipment such as electric motors or transformers where grain growth and residual stresses may affect the magnetic properties of the material. The most cost-effective process for this heat treatment is through a continuous atmosphere with a reducing atmosphere (often provided by a lean Exothermic gas atmosphere). For this process, the atmosphere requires a specific range of hydrogen alongside a controlled heating and cooling recipe with multiple stages.
Premier Furnace Specialists also provides the accessory equipment that can be required for a complete annealing operation. We will build the Exothermic gas generators (rich and lean), Exothermic gas dryers (air and water cooled), nitrogen/methanol/hydrogen (or other bulk atmosphere) gas trains/delivery systems, water recirculation and convective cooling systems, load management equipment/software, and any other required pre/post processing equipment right here at our facility in Farmington Hills, MI. By building all of the ancillary equipment alongside the annealing furnace, it allows the client to benefit from installation of the entire system at once, identical spare parts across all pieces for easier maintenance, identical control systems with consistent terminology for ease of operator training, a single contact source for all engineering assistance and troubleshooting, as well as a service department capable of quickly responding to requests for both our equipment and any other equipment the customer may already have.
A 16 ½ ft. wide x 9 ft. high x 125 ft. long roller hearth furnace with four
heating zones and two cooling zones. Maximum temperature of 1500°F,
nitrogen gas atmosphere.
Concerning efficiency, combustion heating systems can be customized with preheat and recuperation systems, recuperative or regenerative burners, or multi-legged radiant tubes to minimize gas train complexity and NOx emissions while maximizing efficiency and profitability. Electrically heated systems can be equipped with SCR power controls which minimize temperature swings at setpoint, provide optimum work chamber uniformity by eliminating heat surges, and conserve energy by reducing current draw at operating temperature. Processes can also be equipped with digital atmosphere analyzers, flowmeters, and gauges capable of displaying the remote equipment conditions at localized control stations or on mobile devices.
What Are Best Practices for Training In-House Operators on Roller Hearth Annealing?
Specifically for roller hearth furnaces, operators and maintenance personnel must understand the rollers and drive systems to ensure products continue processing at a correct rate. For continuous systems in particular, drive failures may result in the loss of large volumes of product that often cannot be recycled as well as lengthy purge/shutdown/ startup times.
As an example, chain and sprocket driven rollers just only be locked down on the drive side of the furnace so that thermal expansion allows them to grow on the idle side. Otherwise, the sprockets may walk out of alignment and cause a multitude of long and short-term issues such as rollers seizing and warping, drive faults, load crashes, and timing issues between multiple driven segments.
Th e best practice would be for operators to be trained to understand how major components of the furnace may affect the part quality. This knowledge will also assist in troubleshooting issues that may arise and correcting them before they become worse.
What Are the Furnace’s Operational Advantages?
Roller hearth furnaces can handle a large assortment of part sizes by varying the roller diameters and spacing between them. For small parts, the rollers can be used to drive a mesh/cast belt or convey trays. For long parts, they can rest on the rollers with multiple support points. The bar, pipe, and tubing industries use incredibly long roller hearth furnaces while many industries process heavy wire coils in them. By segmenting the roller drives and utilizing VFDs or servomotors, roller hearth furnaces become capable of staging loads, customizing processing times, and oscillating at temperature to prevent rollers from warping under heavy loads.
What Is the Most Common Heating Method?
Premier has seen a steady demand for gas fired roller hearth equipment, but most quotes nowadays also request pricing for an electric alternative to compare against. The end user’s facility location and local utility regulations are typically the deciding factor.
What Are the Challenges in Operating This Type of Furnace?
A common challenge for any continuous furnace is maintaining consistent production and limiting shutdowns or idle periods. Large continuous furnaces burn up a significant amount of energy even when idling, so any time spent not in production becomes costly. Even when the equipment sits powered down, start-up procedures including insulation dry-outs, inert gas purge requirements, and atmosphere seasoning can take days until production can resume.
However, once consistent production is maintained, part quality, part consistency, and energy efficiency can be noticeably better than batch equivalents.
Issues can be avoided by noting areas of concern as they arise and following routine maintenance procedures until scheduled annual or biannual shutdowns (often around holiday breaks). Then additional time can be given to address potentially major issues with service visits and inspections by OEM service teams.
An Eye on Energy
Reiterating the customizable nature of this style furnace, Ryan Sybo, project manager at SECO/WARWICK USA, comments on the attention on energy usage that clients and suppliers share.
What Features Do You Offer on Your Roller Hearth Furnace for Annealing Various Materials?
Ryan Sybo, Project Manager,
SECO/WARWICK USA
We offer a wide variety of options as a custom furnace company. We can tailor the furnace to meet the unique needs of individual clients. On annealing furnaces specifically, we offer a controlled cool chamber and a steam blue chamber.
Individual roll sections can be started, stopped, reversed, oscillated, and run at the same speed or at different speeds for maximum process versatility.
Atmosphere integrity is assured through welded gas-tight shells, sealing doors, and pressure control systems.
Fast and slow heating and cooling rates are possible. Plus, pre-heating can be employed.
Post-heat treating processes like steam blue are possible.
Furnace doors are specially constructed and insulated for operation within the temperature zones in which they are located, minimizing stress and warpage caused by temperature differences.
Heating and cooling sections incorporate dependable, high-quality components for long-life operation.
High-speed transfer between sections allows closely spaced workloads or work trays with separation during transfer through doors, assures optimum use of hearth space, and minimizes atmosphere mixing. All door openings can be adjusted to workload heights, permitting faster operation and minimizing atmosphere mixing.
How Is Your Roller Hearth System Unique?
The controlled cool chamber offers precise control of the cooling rate. The steam blue chamber is used to develop a blue oxide, Fe3O4, for electrical insulation characteristics.
Our company has been designing and manufacturing furnaces for over 123 years, and we have been exploring new refractory materials and more energy-efficient burners and recuperators, as well as offering state-of-the-art atmosphere controls.
What Are Best Practices for Training In-House Operators on Roller Hearth Annealing?
Our furnaces are all built to the latest NFPA 86 and OSHA standards, however, safety training like HMI is also important.
What Are the Furnace’s Operational Advantages?
Several of this furnace’s operational advantages include:
Continuous Unlimited Work Flow: Provides better efficiency than batch processing since the workload can continuously feed into the furnace.
Quick, Easy Installation: For SECO/WARWICK USA, these are normally built at our manufacturing facility and tested, then disassembled into sections to fit on a truck or shipping container.
Long Life: A 40-year lifespan is typical. Less stress on furnace components from faster or constant temperature recycling when compared to belt, chain, or pusher units.
Smaller Factory Footprint: Manufacturers can save about half of the floor space than with multiple batch units.
Flexible Operation: Roller drives can be slowed, sped up, or stopped. Process parameters can be changed, any atmospheres can be used from H2 to air, plus door separations can be used between sections for better separate processing functions.
Lower Production Costs: Each furnace is custom-designed for continuous operation at the desired operating temperatures. Less waste from heat-up and cool-down cycles used in batch systems and in-line processing makes energy recuperation easier to integrate.
What Is the Most Common Heating Method?
Gas fired is the most common, however, we have been seeing a lot of inquiries for electrically heated roller hearth furnaces.
Geographic location is also a big determining factor because some areas have more access to natural gas that can offer reduced operating costs.
What Are the Challenges in Operating This Type of Furnace?
There are no challenges in operating this type of furnace due to our custom-engineered, user-friendly automatic furnace controls. Preventative maintenance can be included in our control systems to remind operators and maintenance personnel to service the equipment. Furnace data and alarms are logged and ready for download and review.
Leveraging Efficient Designs To Process Heavy Workloads
Kelley Shreve, general manager at Lindberg/MPH, hones in on the significance of roller hearth furnace workload capacity as a lynchpin to heat treat operations.
What Features Do You Offer on Your Roller Hearth Furnace for Annealing Various Materials?
Kelley Shreve General Manager Lindberg/MPH Source: Lindberg/MPH
Our roller hearth furnaces are designed to meet the need for accurate, consistent, and efficient processing of heavy workloads. Features include a sturdy roll design for smooth load motion, high-efficiency heating systems for rapid heat transfer, integrated control systems for accuracy of operation and ease of troubleshooting, and material handling systems that simplify operation. Together, these features provide furnaces that will make operations more competitive.
How Is Your Roller Hearth System Unique?
What separates Lindberg/MPH from competitors is our ability to take standard designs and customize them so they are tailor-suited to meet the exact client specifications and floor plans.
Extensive experience in ultra-clean heat treating helped us improve roller hearth equipment as well. Traditionally designed furnaces have transfer sections open to air, which allows rapid heat loss and causes scaling or discoloration of the work. Our proven design shields the work with a directed flow of protective atmosphere through double-door transfer sections. This also ensures isolation of furnace zones that must not be cross-contaminated. An independent, high-speed roll system minimizes transfer time and heat loss. The sight-ports allow direct viewing of work-in-process for easy troubleshooting. The result is clean, consistent work.
What Are Best Practices for Training In-House Operators on Roller Hearth Annealing?
Lindberg/MPH offers complete installation packages which include installation, startup, and training. In-house operators are fully trained on all aspects of operations while our service technician is present.
What Are the Furnace’s Operational Advantages?
Our roller hearth furnaces combine the latest technology in process controls, atmosphere systems, and material handling systems. These furnaces are designed to carry very heavy workloads at high production rates at the lowest possible operating cost. Other advantages are that a roller hearth can be designed to run a multitude of different processes as required.
What Is the Most Common Heating Method?
Roller hearth furnaces can be supplied with either gas fired or electric heating. Gas fired Single End Recuperated Tubes (SERT) provide economical, rapid heating. Electric heating offers reliable, low-maintenance operation using elements tailored to atmosphere application.
What Are the Challenges in Operating This Type of Furnace?
Annealing produces
parts with reduced
hardness and a uniform
microstructure as a
preparation for further
processing. The furnace
has a high-heat section
followed by a controlled
cooling module.
Endothermic, Exothermic,
and nitrogen-methanol
atmospheres are typically
used.
A challenge for this type of furnace is proper maintenance. Operators should manage this challenge by monitoring the preventative maintenance (PM) features and indicators that are available. Setting in place and following a regular PM schedule is going to help ensure the equipment operates dependably and problem free.
ALRO, one of the largest vertically integrated aluminum producers in Europe measured by production capacity, has purchased an aluminum aging furnace with electric heating. The project objective is to increase the output of high and very high added products.
The SECO/WARWICK furnace has been designed for aging type 2xxx, 6xxx and 7xxx aluminum plates with a length of up to 13,000 mm and a width of up to 2,200 mm. They can be arranged in one or two rows. The load will be placed horizontally on loading trays with themaximum capacity of 60 tons net. The furnace will be heated electrically, which will significantly reduce CO₂ gas emissions.
This electric furnace will replace three furnaces powered by natural gas with the aim of streamlining the heat treatment operations within the ALRO Processed Aluminum Division. The furnace represents an important step towards achieving the company's goal of becoming a greener producer.
Piotr Skarbiński, Vice President of the Aluminum Process and CAB Business Segments, SECO/WARWICK
Piotr Skarbiński, vice president of the Aluminum Process and CAB Business Segments at SECO/WARWICK, explains, “The challenge of reducing emissions is becoming an increasingly important purchasing impulse for customers. This applies in particular to European producers, because in this region of the world ecological regulations are currently the most restrictive. The aluminum aging furnace, powered by electric heaters, eliminates the emissions problem, hence the growing interest of aluminum producers in such solutions.”
Gheorghe Dobra, CEO, ALRO (Source: Alro.ro)
Gheorghe Dobra, CEO at ALRO, commented, “The new equipment, provided by SECO/WARWICK, will support our program to maximize the value of the products we are manufacturing and will allow us to better serve our customer’s requirements. At the same time, the new technology will support our commitment to reduce our environmental footprint.”
"We have already completed several orders for new equipment for this customer," said Tomasz Kaczmarczyk, sales manager of the AluminumProcess and CAB FurnacesTeams at SECO/WARWICK, "including a gas aging furnace and ingot preheating furnace. We have also modernized furnaces for annealing aluminum sheet coils."
Tomasz Kaczmarczyk, Sales Manager of the Aluminum Process and CAB Furnaces Teams, SECO/WARWICK (Source: SECOWARWICK.com)
Aging furnaces are designed to operate in the temperature range from 176ºF to 482ºF in accordance with the AMS2750G standard. The temperature uniformity guarantee throughout the entire load at the level of +/- 3ºC was achieved with the use of optimal heat flow inside the furnace using high-performance atmosphere mixers and a system of guides directing the air stream.
This press release is available in its original form here.
Consider the numerous systems in your heat treat operations. What makes up the anatomy of each furnace? In this “Anatomy of a . . .” series, industry experts indicate the main features of a specific heat treat system. In this feature, the full-page spread identifies main features in a roller hearth furnace.
The mark-ups for these reference images are provided by Premier Furnace Specialists.
Download the full graphics by clicking the image below.
Search www.heattreatbuyersguide.com for a list of roller hearth furnace providers to the North American market. If you are a roller hearth furnace supplier and are not listed here, please let us know at editor@heattreattoday.com.
This series will continue in subsequent editions of Heat Treat Today’sprint publications. Stay tuned!
Find Heat Treating Products And Services When You Search On Heat Treat Buyers Guide.Com
HAMR titanium furnace for Virginia facility (Source: IperionX)
IperionX announced their HAMR (Hydrogen Assisted Metallothermic Reduction) furnace has completed its final mechanical assembly and passed factory acceptance tests. The furnace will be delivered to the company’s Virginia Titanium Production Facility as a foundational asset to the low-cost titanium supply chain.
The HAMR furnace is a large-scale titanium furnace with IperionX-patented technologies. HAMR is a powder metallurgy process technology that allows for the production of titanium powders.
Installation is expected during 2024’s second quarter, with production of titanium beginning mid-2024. To ramp up low-cost titanium production, IperionX has received $2.4 million from the DoD as part of a $12.7 million grant fund.
To learn more about IperionX’s Viriginia Titanium Production Facility, visit this link.
This press release is available in its original form here.
How long until heat treat operations use hydrogen for combustion? Considerations like cost and pipeline infrastructure are key in answering this question. For these industry experts, the consensus is clear: It is uncertain when, but hydrogen is coming. Doug Glenn, publisher of Heat Treat Today, moderated a panel of four industry experts in 2023 during which they addressed topics about advancements and challenges surrounding hydrogen combustion. Read an excerpt of their answers below. For the full interview go to www.heattreattoday.com/hydrogen2023.
What’s New for Hydrogen?
Dr.-Ing. Joachim G. Wuenning President/Owner WS Wärmeprozesstechnik GmbH
Joe Wuenning: In Europe, several steel companies are getting large funds to really go in on the hydrogen road to make green steel. If you have green steel, you will also convert the downstream processes. These places are large locations where the steel plants are running.
Automotive companies will ask for green steel. How long will it take until the heat treat shop will get to the point of using hydrogen for combustion is uncertain, but I’m sure it will be, in the end, coming also there.
Brian Kelly Applications Engineering Manager Honeywell Thermal Solutions
Brian Kelly: We have seen projects secured that have come to fruition firing on hydrogen. They’ve fired on hydrogen to prove it works and then moved back to natural gas since the H2 supply is not readily available.
What we’ve seen in the U.S. is a slowdown in some of the inquiries and questions about hydrogen. There may be a slowdown in the fervor of the talk about hydrogen, but it is certainly in the background and maybe a little bit more towards how do we be more green until hydrogen gets here?
Robert Sanderson Director of Business Development Rockford Combustion
Bob Sanderson: We’ve seen more inquiries, specifically from a lot of laboratory users who are trying to develop new engines, processes, and combustion products and looking for all the support and the technology to safely handle transport and bring that hydrogen into the lab under various test conditions.
A few users, too, want to understand: If they make the change to hydrogen, what’s going to happen with the rest of their systems?
Mark Hannum Manager of Innovation and Combustion Laboratory Fives North American Combustion
We have seen some early hydrogen requests going on which have tapered off a bit. I think it goes hand in hand with users becoming more familiar with the systems and having more of their questions answered. But I think some of it also depends a bit on the market pressures and the demands. The cost of natural gas has gone down dramatically. It’s going down faster than the cost of hydrogen is coming down. Hydrogen is going to keep coming down and keep becoming more and more affordable. Then it will reenter into the marketplace.
Mark Hannum: Probably the biggest thing is some of the regulatory and law changes that have happened. The Inflation Reduction Act certainly puts in place a lot of supports for hydrogen production and hydrogen-based systems for decarbonization.
Burgeoning Users of Hydrogen
Kelly: New inquiries have come from a lot of different places for us. We’ve had food and beverage, some heat treating, and plastics. Some of the inquiries have been waste to energy, sequestering CO2, and capturing the hydrogen. That’s how we’re going to produce it.
Wuenning: Our business is in the steel and heat treating industry. I’m not so much in touch with the other industries, but I think it would come from everywhere — everywhere the people are willing to pay for it. Of course, we have never beat natural gas on price, so far. Hydrogen is never going to come free out of the ground. But we all know the reasons why we want to get rid of the fossils.
In heat treat, we see another tendency, and that is the use of ammonia. We try to check out whether we can use ammonia because with hydrogen you need pipeline connections, and it will take quite some time until the pipelines will carry hydrogen to the last little heat treater somewhere in the countryside.
Hannum: One of the nice things about hydrogen is if you have a clean source of water and electricity, you might be able to make hydrogen in a remote location. You might not need to pipeline it; you could make the gas and use it on site.
The need for pipeline infrastructure is a key issue in the use of hydrogen.
In the steel industry in Europe, these major investments are being played out and committed to, but we’re years away from being adopted, for day-in and day-out use.
There are a lot of segments that are performing really meaningful tests at the industrial scale because they’re all trying to de-risk the switch from natural gas to hydrogen. Are there any process-side impacts that they need to understand that would impact product quality or product suitability or any of those things? All that stuff is going on now, and I think it’s going to take a couple of years for everyone to sort of work through and have a good understanding of whether there’s anything they need to be worried about beyond just the fuel switch itself, if there’s any process.
Sanderson: A lot of the push I’ve seen has come out of the aerospace and the automotive industries, not so much on the products that they make but more on the manufacturing side of it.
Advancements and Challenges with Hydrogen
Sanderson: We’re doing a lot more work now with stainless materials. There is quite a bit of involvement using stainless and other materials that have higher nickel contents and other materials to help work into the grain boundaries.
Working with hydrogen has some unique challenges compared to other fuels. It’s the smallest atomic molecule out there and it just wants to permeate into everything. With a lot of the higher, high-end pressures, there is a lot of chance of steel embrittlement, but if you can get away from those higher ends and try and get down to more usable, friendly working pressures, you don’t stand as much risk on the hydrogen embrittlement and dealing with leaks and permeability. So, just helping people understand that those are some of the changes that need to come into play for a safe, long-term solution in their applications.
Hannum: We have installed some hydrogen-firing capability in our lab; it was about a $400,000 investment. So, at this point, we can fire a substantial amount of input for longer durations than we could before. So, that’s really helpful when we’re looking at what the impacts are across our entire burner product range, when we look at a conversion from natural gas to hydrogen.
It also lets us perform some process-based studies where we can really simulate industrial processes and have a longer duration hydrogen firing. So, we’ve been able to support some customers by simulating some of their processes here and actually firing the materials that they would normally fire at their plant to look at hydrogen impact on those materials.
We’ve also gone to a couple of our customer sites and participated in studies with them. One of those earlier this year, right after THERMPROCESS, was Hydro Aluminum in Spain; we melted aluminum with hydrogen without any natural gas. That was, I think, the first industrial scale melting of aluminum with hydrogen.
Wuenning: We have now put into place an electrolyzer for making our own hydrogen, and not relying on the bottles coming in or on ammonia supply. We installed a big ammonia tank so that we can run the ammonia tests on site, develop the crackers and account for them. And, of course, we are involved in several research projects together with universities and some sites that do all these things to try it out.
Kelly: The latest this year is an investment for one of our factories to have an electrolyzer-type system, so a full-blown, cradle-to-grave type of system to be able to produce the hydrogen. Muncie is investing in that whole substructure with the capability of increasing to tube tankers before the electrolyzer comes so there is significant investment on that end. And from the product end, we’ve just kept testing and looking at the whole product line, not just burners, but all the controls and things to be associated with hydrogen firing.
In addition to the controls behind the system, we must also think about the development of simpler and/or more complicated systems. These updated systems are necessary because of changes in air/fuel rations and all the concerns that pop up when using different fuels.
These systems need to take into account what the process is requiring, namely holding tighter air/fuel ratios and also being less dependent on low temperature air-heating applications, but also being able to use higher temperatures and higher oxygen rates with some excess air. We’ve been working on those types of systems and looking at that when the clients are in a situation where they can fire on either fuel. How critical it is to hold capacity and air/fuel ratio and things of that nature, and how can we make that as easy as possible for the client?
But, yes, a lot of activity on that basis. And even in product development looking at the future — lower NOx and lower emissions burners that go in conjunction with hydrogen. In the lower and high temperature range, we’ve got to look at a burner that can fi re via flex-fuel type burner. Maybe not just hydrogen and natural gas but something in biofuels or renewable-type fuels.
Automating Brinell hardness testing could mean saving on expensive laboratories, as was the case for one oil tool industry manufacturer. Learn the basics of Brinell hardness testing, its strengths and weaknesses, and options for automation.
This Technical Tuesday article, written by Alex Austin, managing director of Foundrax Engineering Products Ltd., was originally published in Heat Treat Today’sDecember 2023 Medical and Energy Heat Treat print edition, both in English and in Spanish.
Brinell Hardness Testing: Strengths and Weaknesses
Alex Austin, Managing Director, Foundrax Engineering Products Ltd.
In many steelworks producing large forgings and billets, in numerous heat treatment companies, and near many factory lines producing components for safety-critical applications, you’ll find a Brinell hardness tester. These machines have been used all over the world for more than a century (the test was first demonstrated by its inventor, the Swedish metallurgist August Brinell, in 1900), determining metal hardness by means of a tungsten carbide indenter ball that leaves a dish-shaped indentation in the surface of the test material.
In the test, the material sample is placed on a rigid anvil, and the indenter descends onto it under loads ranging from 1 kg up to 3,000 kg, depending on the material. Indenters vary in diameter from 1 mm to 10 mm. Most tests use a 3,000 kg load and a 10 mm ball, and the standards always refer to this as “HBW 10/3000.” HBW stands for Hardness Brinell Wolfram, Wolfram being another name for the tungsten carbide the indenter ball is made from. After the (approximately) fifteen second indenting cycle, the indentation is measured across both its x and y axes, as a minimum, by a special calibrated microscope. The mean of the diameter readings is then fed into the Brinell equation.
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Naturally, most technicians would rather not use that equation, so they look the indentation diameter up on a chart and “read across” to the derived hardness.
The great advantage of the Brinell test, when considered alongside other metal hardness testing methods, is that the large indentation diameter (typically between 2.4 mm and 6 mm) means the test result is generally unaffected by the grain structure of the metal. It also means that the surface of the test sample can be adequately prepared in just a few seconds with an angle grinder. For these reasons, the test is regarded by many as the “default” one for rough-surfaced and/or coarse-grained samples.
On the block in image (Figure 4), the distortion around the indentations can be seen very clearly.
That seems pretty simple, but there are inherent weaknesses in the Brinell test: measuring the indentation. In our previous article (read it in Heat Treat Today’s August 2023 Automotive Heat Treat print edition), we used this image (Figure 2) to illustrate how difficult it could be to work out exactly where an indentation edge begins and ends.
You might look at Figure 2 and think, “I’m pretty confident about where that indentation edge is,” but it’s trickier than it looks, because the process of indenting doesn’t just push material downwards; it also spreads it sideways, and you get a “pile up” around the rim of the indentation. The pile up may be difficult to see on hard material, or there may be a subtle “lip” inside the pile up that represents the true edge, but considered in cross-section, indentations look roughly like this simple sketch above (Figure 3).
Figure 2. Measurement of Brinell hardness test indentation (Source: Foundrax Engineering Products Ltd.)Figure 3. Sketch of cross-section of indentation (Source: Foundrax Engineering Products Ltd.)
The overhead light illuminates the “pile up” rim very clearly on some of those indentations as a highlight around the edge. Where, exactly, does the pile up end and the true edge of the indentation begin? Bear in mind that 0.2 mm can equal 20 hardness points. You could show an indentation to three experienced workshop technicians and receive three different answers to the diameter question, and this problem has been a challenge of the Brinell test from its inception. Special blocks are available for training technicians in measurement, but the problem of operator interpretation was such that, in some quarters, the Brinell test was regarded as a bit “rough and ready.” “Ok for the workshop but not for the lab,” was perhaps how it was once seen.
Why Automate the Brinell?
The first question to consider when looking at the automation of the Brinell test is the measurement system because this is the inherent weakness. There are, of course, applications where only narrow tolerances are acceptable, and disagreements can arise between customers and suppliers.
Over the years, certain manufacturers, who mill heat treated materials for the oil tool industry, confided to us that they were regularly using expensive testing laboratories because of clients disputing the hardness figures of their products. They had previously been using manual microscopes. Obviously, this has reputational, as well as financial, consequences. If a manual microscope is employed on raw materials at the goods-in-process stage and there’s an error reading the hardness, you could find at final machining that you have put a lot of time and effort into a part that, in the end, is too hard or soft for the intended application.
Manually manipulating the microscope may not be worth the effort, especially when even a diligent operator may read the result incorrectly. With an automatic Brinell microscope, however, there is the possibility of major time and cost savings.
4 Levels of Automation
#1 Beginnings of Brinell Automation
The first step in automating Brinell hardness testing began 40 years ago when the world’s first automatic measurement microscope hit the market. The system, still being regularly refined, was able to measure the diameter of the indentation across over 100 axes, calculate the mean, and determine the hardness in a split second. It can handle most surface irregularity, operate in poor lighting, and warns operators of unacceptable surface preparation. Additionally, its precision adjusts for spatial error when lining up with a graticule. Within a few years of launch, a major oil tool manufacturer’s quality chief recommended its use to his suppliers, and user uptake was rapid.
#2 Integrated Microscope Model
A further step in automation is to dispense with operator handling of the microscope entirely by the acquisition of a tester with an integrated microscope. The microscope mentioned above, for example, is a feature on several hardness testing machines. The heavy-duty indenter holder pivots away from its normal line of thrust at the end of the indenting cycle, allowing a supra-mounted camera to view the indentation. This is hugely advantageous: no separate apparatus near the test machine, reduced handling time, and thus, much faster testing overall. Results from such machines are displayed next to the control panel and quickly uploadable to company quality systems.
Figure 4. Block with distortion around indentations (Source: Foundrax Engineering Products Ltd.)
#3 Dispensing of Manual Operations
Another automation option is to dispense with a hand-cranked anvil capstan and purchase a tester with a fixed anvil and movable test head. The technician is not required to manually raise and lower the anvil to allow for variations in the size of sample. Instead, the test head automatically “takes up” the space and also clamps the test piece very securely in place during the test cycle.
#4 Incorporate Custom Hardness Tester in Production Line
The fourth, and obviously most dramatic, automation step to consider is incorporating a custom-designed hardness tester into the production line. In some industries, this is essential. Large billets and forgings can’t be lifted into the jaws of a benchtop or floor-standing Brinell tester; so, for highly accurate testing of such items, a larger machine is required (Figure 5).
Figure 5. A custom-designed production line hardness tester. This machine is now in Texas. (Source: Foundrax Engineering Products Ltd.)
The whole gantry moves on one axis of travel while the test head moves perpendicular to that and, of course, up and down. This provides the full x, y, z movement. Large samples are maneuvered on and off by crane. The test head assembly incorporates the automatic microscope and results are displayed on a screen beside the control panel. Test results can be instantly uploaded to factory quality systems. The head assembly can also incorporate a milling tool for surface preparation!
With any decision to purchase plant and machinery equipment, some form of cost-benefit analysis is worthwhile. Clearly, if you’re doing a significant amount of business annually with a customer who is threatening to cease contracting with you because your hardness measurements are wrong too often, then the decision to buy an automatic microscope is not a difficult one. If staff are on overtime because mandatory hardness testing is adding too much time to production schedules, then a heavy-duty production machine with automatic microscope, movable test head, and sample clamp will pay for itself easily.
One thing is certain: Every automation option in Brinell testing increases accuracy and saves time.
About the Author
Alex Austin has been the managing director of Foundrax Engineering Products Ltd. since 2002. Foundrax has supplied Brinell hardness testing equipment for 60+ years and is the only company in the world to truly specialize in this field. Alex sits on the ISE/101/05 Indentation Hardness Testing Committee at the British Standards Institution. He has been part of the British delegation to the International Standards Organization advising on the development of the standard ISO 6506 “Metallic materials – Brinell hardness test” and is the chairman and convenor for the current ISO revision of the standard.
