www.process-heating.com | April 2011 | Volume 18, Number 4
Super Heating Use process boilers to generate superheated, high pressure steam. Find suppliers using our Equipment Overview.
Periodical Class
14 Tips for Upgrading Your Oven 17 Overcoming Cable Resistance Errors
These heaters will be fully assembled and checked at our factory before delivery.
Get a complete heater package Need a new heater? Get a complete heater package from Heatec. A complete package eliminates hassles, saves you time and saves you money. Our package includes design, manufacturing, factory assembly, on-site setup and startup. We also offer maintenance contracts and provide free phone support. Heaters have many components from a variety of manufacturers. It’s always best to mate these components with the heater and adjust them before the heater is shipped to you. This eliminates most compatibility problems. Our goal is that setup of our heater at your plant will be trouble free, without undue rework. Most setups should only require re-assembly of parts dismantled
for shipping, plus connection of electrical power and piping. Complete factory assembly eliminates last-minute fieldwork that can cause startup delays. It also eliminates buck passing if things don’t go right. Moreover, if a problem develops later, you won’t have to wrangle with a variety of component suppliers to fix it. So, when you buy a new heater, always choose a manufacturer that provides a complete package. Heatec has this capability, which sets us apart from others. Call today and let us answer any questions you have about our heater packages.
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April 2011 Volume 18 • Number 4
www.process-heating.com WEB EXCLUSIVES: READ MORE AT WWW.PROCESS-HEATING.COM Q A Working Relationship is Key to a Successful Project
page
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Ovens Whether it is time to replace an existing industrial batch oven, upgrade a process with a new oven or set up an entirely new process that requires an industrial batch oven, there are numerous questions that may arise about how to put together the justification for a capital expenditure.
Temperature Sensors Finding Your Balance Many sources of error exist in process applications, and they can impact the accuracy of a resistance temperature detector (RTD) measurement. The cable incorporated into the sensor can cause significant error, but this effect can be minimized.
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Equipment Overview: Boilers Super Heating Use process boilers to generate superheated, high pressure steam. Find suppliers using our Equipment Overview.
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Companies do not have time to buy a piece of capital equipment and spend weeks or months in trial and error striving to optimize their process. There are a number of errors typically made during RTD selection and installation.
Making the Right Choice
17
Q The Value of Pilot Line Trials
Q Common Sources
Features 14
The amount of information relative oven selection is astounding and can be challenging when making a decision on your next oven purchase.
Heaters A Winning Combo The challenge was to come up with a process that would increase production while maintaining the necessary high level of product quality. Combining infrared and convection technologies solved it.
Q Isobutanol Produced Directly from Cellulose BioEnergy Science Center researchers have devised a new bioprocessing method combined with a transgenic microbe to save two steps on the way to producing biofuels.
UPDATED DAILY Q New Products
Q Industry News
ALWAYS ONLINE Q Archives Q Calendar of Events Q Drying Files columns
Q Energy Notes column Q Equipment Overviews Q Heating Highlights
Q Digital Editions Q Buyers Guide Q Archived Webinars
Check out our redesigned site with more frequent updates and web exclusives! Q Go Mobile Use your smart phone to read Process Heating, wherever you are! Simply visit http://gettag.mobi/ with your phone’s browser to install the Microsoft Tag app. Then, point your phone’s camera at the tag below to be taken to our current issue online — instantly. The reader works on most current smart and advancedd ffeature phones, h includi l d ing Windows Mobile (5.5 and above), iPhone, Blackberry, Symbian and J2ME.
About the Cover page
17 Columns & Departments 6
Editor’s Page
27 Free Literature
7
Inner Workings
28 Classified Directory
13 Calendar
29 Advertiser Index
25 Products
30 Places & Faces
At a plant in the Southeast, a biomass energy system from Hurst Boiler and Welding Co. Inc. (www.hurstboiler.com), Coolidge, Ga., receives a woody biomass fuel stream (~50 percent moisture content, wet basis) and converts this fuel into thermal energy using its close-coupled gasification process. The thermal energy then is transferred into Hurst’s hybrid boiler vessel to generate superheated, high pressure steam, which is used to drive a turbine genset to make electricity used on site. To learn more about boilers, see page 20.
PROCESS HEATING (ISSN 1077-5870) is published 12 times annually, monthly, by BNP Media, 2401 W. Big Beaver Rd., Suite 700, Troy, MI 48084-3333. Telephone: (248) 362-3700, Fax: (248) 362-0317. No charge for subscriptions to qualified individuals. Annual rate for subscriptions to nonqualified individuals in the U.S.A.: $115.00 USD. Annual rate for subscriptions to nonqualified individuals in Canada: $149.00 USD (includes GST & postage); all other countries: $165.00 (int’l mail) payable in U.S. funds. Printed in the U.S.A. Copyright 2011, by BNP Media. All rights reserved. The contents of this publication may not be reproduced in whole or in part without the consent of the publisher. The publisher is not responsible for product claims and representations. Periodicals Postage Paid at Troy, MI and at additional mailing offices. POSTMASTER: Send address changes to: PROCESS HEATING, P.O. Box 2146, Skokie, IL 60076. Canada Post: Publications Mail Agreement #40612608. GST account: 131263923. Send returns (Canada) to Pitney Bowes, P.O. Box 25542, London, ON, N6C 6B2. Change of address: Send old address label along with new address to PROCESS HEATING, P.O. Box 2146, Skokie, IL 60076. For single copies or back issues: contact Ann Kalb at (248) 244-6499 or
[email protected].
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By Linda Becker
Commentary Early Lessons from the Tsunami
Are You Prepared Enough? The tsunami that hit the coast of Japan on March 11 already has had a devastating effect on the people of Japan. Hindsight brought with time and experience will best show us the primary lessons learned. Yet certainly, for any industrial processor, one must be the lesson of the Tokyo Electric Power Co. and its Fukushima Daiichi power plant. Fortunately, at least as I write this, the worst of the nuclear threat has been contained. And so, the questions begin about why the tsunami so devastatingly crippled the plant. Did the company do enough to anticipate and prepare for the known risks? News reports show that TEPCO conducted geologic and surveys to assess their emergency preparedness, a given for a company located in an earthquake and tsunami prone area. The plant was constructed to withstand an 18' wave; unfortunately, it was hit by a wave more 4' higher. However, according to news reports, it appears TEPCO failed to secure its emergency generators adequately. The quake pushed water over the nuclear power plant’s emergency generators, and those generators failed. As Dr John Large, an independent nuclear engineer and nuclear safety expert, said in The Telegraph: “These plants should be designed to be resistant to tsunamis, but it appears they did not consider that a tsunami would
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A p r i l 2 0 1 1 • Process Heating
hit the plant when they were using the backup generators.” Already, U.S. legislators are meeting to assess the risk here, particularly in areas at greater risk for earthquakes and tsunamis such as the California coast. Federal experts testifying in Sacramento noted that that Japan’s nuclear industry built power plants to withstand substantial quakes — just not as large as the one that struck. According to Southern California Public Radio, lawmakers there are calling on the state’s nuclear power plant operators to revisit the risks of an accident from a major quake or tsunami. Of course, while we can plan for those common-cause risks and work to mitigate them, there will always exist those outliers — events so unlikely that they fall on the outer extremes of possible bad outcomes on a Bell curve. To what degree do we legislate that our plants be designed to withstand those risks? And at what cost? Perhaps we will know that answer better now.
Linda Becker, Associate Publisher and Editor,
[email protected]
Inner Workings
Phasing Out Industrial Mercury Thermometers Mercury-containing thermometers are being phased out across the United States in an effort to rid the environment of the neurotoxin. Mercury, the only metal that is liquid at room temperature, winds up in our oceans, where it contaminates large food-fish preferred by humans. This is the main source of mercury poisoning in humans. The U.S. Environmental Protection Agency has mercury thermometerrelated questions and answers posted on its website, as well as videos about industrial alternatives. Here is a sampling of what you’ll find. Q. Why are mercury thermometers being replaced? A. Mercury is a neurotoxin and harmful to human health and the environment. Several states prohibit the sale of mercury-containing thermometers. Q. Will the replacement of mercury thermometers be problematic? A. For most applications, alternatives to mercury-containing thermometers are available. However, there are certain applications where the use of alternatives to mercury-containing thermometers is more difficult is more difficult. One example is the use of thermometers in high temperature devices such as autoclaves; however, this is an application in which mercury is not commonly used. (The website provides “User Friendly Guide on the Replacement of Mercury Thermometers” in PDF format on the website.) Q. What types of non-mercurycontaining thermometers are currently available? A. There are several types, including both liquid-in-glass and electronic digital thermometers. An example of an electronic digital thermometer is the platinum resistance thermometer. Others include the thermistor and the thermo-
Q. Are alternative thermometers more expensive than mercurycontaining thermometers? A. Electronic thermometers are typically more expensive than mercurycontaining thermometers. However, using non-mercury-containing thermometers avoids the potential cost of mercury spill cleanup and disposal. Industrial facilities with mercurycontaining thermometers must dispose of them with care. They can be:
couple. Non-mercury organic-liquidfilled glass thermometers are also a replacement for mercury thermometers. Q. Are non-mercury-containing thermometers as accurate as mercurycontaining thermometers? A. The non-mercury platinum resistance thermometer is as accurate as mercury-containing thermometers through a wide temperature range. Non-mercury thermistors are accurate but have a limited temperature range. Non-mercury thermocouples are not as accurate as resistance thermometers or thermistors, but are widely used because of their durability. Non-mercury liquid-inglass thermometers are not as accurate and are typically used when applications call for modest uncertainty requirements. Q. Are non-mercury-containing thermometers as durable as mercurycontaining thermometers? A. Like a mercury-containing thermometer, the platinum resistance thermometer is sensitive to mechanical shock. Thermistors are less sensitive and thermocouples are very durable. Non-mercury liquid-in-glass thermometers are as durable as mercury liquidin-glass thermometers.
• Shipped through a hazardous-waste transporter to a mercury recycling facility. • Directly shipped as “universal waste” to a mercury recycling facility. • Disposed of by small businesses at a local collection event, collection facility or destination facilities for “universal waste.” The EPA notes that prior to disposal, facilities should contact their state hazardous-waste authority for information on state regulations , which vary by state, including the definition of “universal waste.” To see the EPA’s full set of mercurysensor phase-out questions and answers, and to view tutorial videos, go to www.epa.gov/hg/thermometer.htm.
Hydro-Thermal Wins Top Manufacturing Award A maker of direct-injection steam heaters has won the 2010 Wisconsin Manufacturer of the Year Grand Award in the small-company category of one to 99 employees. Hydro-Thermal Corp. in Waukesha, Wis., was recognized for innovative product research, development and engineering over the last 45 years. The company’s steam-injection technology often can be a replacement for other process heating technology such as heat exchangers. “It is a little company [but] a leader in the heat exchange industry,” says John Emory, Jr., one of the judges who represented the financial sector. “The judges www.process-heating.com • A p r i l 2 0 1 1
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Fast and Safe Heating Element Technology (CHE) Developed by Ferro Techniek in the Netherlands, Davidon Industries now offers Contact Heating Elements, or CHE, to the American market. CHE consist of a thick film heating element that evenly spreads the heat over the surface to be heated. So, the heating element itself is spreading the heat, and thus the diffuser plate can be omitted. The heat is transferred to the object to be heated via a graphite sheet. The elements are simply “bolted” to the object; a simple, reliable and effective solution. A • • • • • • • •
summary of properties benefits: Power/heat evenly distributed over a large surface area. Multiple elements on a surface to heat large areas. Less mass required to evenly distribute the heat – Better speed & control. High maximum power of 50 watts/in2 Less accumulated heat – Energy saving. Application specific surface temperatures, powers, sizes. The heated surface can be split into zones that can be controlled at different temperatures. Slim-line design and lower external heat losses – Greater design freedom
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were very impressed with the high degree of specifications in the research and development, as well as the high caliber of their engineering.” Hydro-Thermal, which sells into 45 countries, focuses on several industries, including food, beverage, pulp and paper, biofuel and chemical. For 23 years, the Manufacturer of the Year program in Wisconsin has recognized manufacturers of all sizes and industries for their contributions. Winners were selected by an independent panel of judges representing industry, education and the public sector. For more information about Hydro-Thermal, go to www.hydro-thermal.com.
Toxins Removed in Multiple Applications
Your Total Solutions Representative! Contact us for more information or questions. (401) 737-8380 Website: www.davidonindustries.com • Info:
[email protected]
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Inner Workings
Oxidizers have their own niche in industry: muscling out the harmful byproducts of manufacturing processes. CSM Worldwide Inc., the Mountainside, N.J., maker of catalytic oxidizers, thermal oxidizers, regenerative thermal oxidizers and regenerative catalytic oxidizers, specializes in the removal of volatile organic compounds and nitrogen from exhaust streams, keeping the toxins out of the atmosphere. Applications for oxidizers vary from the mundane to complicated systems. On its website, CSM briefly highlights some of the projects it has handled over the years. Below is a selection of those mini-case histories, which might give
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Inner Workings end-users ideas for their own operations. You can see all the CSM case histories with accompanying images by going to www.csmworldwide.com and clicking on “Installations” in the left-hand index column. • A major commercial bakery replaced its oxidizer with a standard CSM Catox model in inventory. The unit was ordered, installed and operating in three days. “Now that’s customer service,” the customer told CSM. • A large chemical company replaced an existing oxidizer with a state-of-the-art design, 70,000 scfm modular Catox comprised of four individual systems, allowing turndown while maintaining process to one, two or three units. • A commercial bakery had CSM engineer and install 4,000' of process ductwork that was designed for thermal expansion and thermal efficiency. • A customer experienced significant electrical panel shutdowns with an existing oxidizer from another company, and it had CSM integrate and program a new panel to control the oxidizer. • A customer had CSM install emissions controls on a bank of four existing 500 hp packaged steam boilers.
Fire-Safety System Gets Certified Emerson Process Management’s DeltaV SIS process safety system has received certification from TÜV Rheinland, a German organization similar to Underwriters Laboratories in the United States.
Ed Jay, ProHeatCo Owner, Inventor Dies Edward R. Jay, a pioneer in the field of electric heat for the asphalt and other industries, has died in Seattle. He was 85. Born in Nebraska, Mr. Jay moved to Seattle in 1939, where he later went to work for Process Heating Co. He and his partner, Rudy Hentz, bought the company in the 1950s. Mr. Jay and Mr. Hentz invented and patented a new type of electrical element that became the mainstay of Process Heating Co.’s heaters. In 1990, Mr. Jay retired to Whidbey Island, Wash., and turned the company over to his sons Ron and Rick.
Based in Cologne, TÜV is a product safety and quality assurance testing firm for North America, Europe and Asia. It has certified the DeltaV SIS system as meeting the requirements for the following three burnermanagement standards: • National Fire Protection Association, NFPA 85: Boiler and Combustion Systems Hazards Code.
Because our products are top quality Despatch never cuts corners. The products we build are manufactured to the highest industrial standards. Despatch ovens have a reputation for superior process control and dependable operation. Every oven is thoroughly tested and inspected prior to shipment.
INSPIRED INNOVATION
Thermal Processing Technology
phone: 1-952-469-5424
[email protected] www.despatch.com © 2011 Despatch Industries. All rights reserved.
Inner Workings
s 3AVE -ONEY s 2EDUCE %MISSIONS s #ONSERVE 2ESOURCES Miura boilers is environmentallyfriendly steam that saves you money, while saving the planet. Discover Miura’s many other world-leading advantages and efficiencies MIURA Gas or Oil Fired EX Series by contacting us today. High Pressure Steam Boiler
MIURA Gas-Fired/Low Nox LX Series High Pressure Steam Boiler
USA:1-888-309-5574 Canada:1-800-666-2182 www.miuraboiler.com
• European Standard, EN 298: Automatic Gas Burner Control Systems for Gas Burners and Gas Burning Appliances with or without Fans. • European Standard, EN 50156: Electrical Equipment for Furnaces and Ancillary Equipment.
The DeltaV SIS process safety system has received certification for three burner-management system standards.
All the standards cover the design and installation of fuelburning equipment and their associated systems. “With many existing DeltaV SIS installations already being used in burner-management applications, the NFPA 85, EN 298 and EN 50156 product certifications give users additional assurance” that their systems are well-suited for use with fired equipment, says Emerson’s Mike Boudreaux, Delta’s brand manager. To learn more about Austin, Texas-based Emerson and its smart safety system, go to www.emersonprocess.com/sis.
EPA Mandates New Boiler Emission Rules The U.S. Environmental Protection Agency has released its
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Inner Workings
new and controversial rules governing large and small boilers used at “area source facilities” such as industrial plants, institutions and commercial sites. The standards, which fall under the EPA Clean Air Act, will affect about 200,000 boilers, according to EPA estimates, with the vast majority of that
number, approximately 187,000, being small units. Compliance is not required until after February 2014. An area source facility is one that emits or has the potential to emit less than 10 tons per year of any single air toxic or less than 25 tons per year of any combination of air toxics. EPA defines large boilers as
Temperature sensors come in all shapes and sizes.
Because we have the most experience Despatch has over 100 years of proven success in partnering with customers to deliver complex thermal processing solutions. We are committed to working with you to learn the details of your unique process in order to design and engineer a custom piece of equipment that will meet your specific requirements.
INSPIRED INNOVATION Which is right for you? Don’t leave your measurement to chance. Burns ensures fit, performance and temperature confidence. Give us a call and let us put our Temperature Measurement Expertise to work for you!
1.800.328.3871 burnsengineering.com
Thermal Processing Technology
phone: 1-952-469-5424
[email protected] www.despatch.com © 2011 Despatch Industries. All rights reserved.
Inner Workings those with a heat input capacity equal to or greater than 10 million BTU/hr, and small boilers having a heat input capacity of less than 10 million BTU/hr. The EPA anticipates the final rule to reduce emissions of a number of toxic air pollutants, including mercury, metals and organic air toxics, which includes dioxins. The final rule does not apply to boilers that burn only gaseous fuels or any solid waste. To find out how the agency is working with the U.S. Department of Energy to help boiler users determine their best options, go to www.epa.gov/ airquality/combustion/actions.html.
Recovery Boiler Slated for Greenfield Site
s &LUID 0ROCESS (EATING s s &LU UID 0ROCESS (EATIN UID NG s s $ESIGN, %NGINEER AND -ANUFACTURE s #ONTACT OUR %NGINEERING 3ALES TEAM DIRECTLY TEL s &AX INFO HUBBELLHEATERSCOM wwwHUBBELLHEATERSCOM
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A South American startup pulp mill is getting a new recovery boiler and evaporation plant from Metso. Helsinki-based Metso received the order from newcomer Eldorado Celulose e Papel S.A., in Trés Lagoas, Brazil. The Recox recovery boiler for the greenfield site will have the largest capacity of steam generation on the American continent, according to Metso. The evaporation plant will be the largest single-line evaporation plant in the world, with six thermal stages and capacity of 1,600 tons/hr. The plant is scheduled to begin operating in the fourth quarter of 2012.
WE KNOW ELECTRICITY Questions about SCR power control systems? We can help. • Fusing • Cooling • Heatsink Design • Voltage protection • Application assistance For more than 40 years we have been designing and building SCR controls for hundreds of thousands of users like you.
For answers to your solid state control questions
Call 1-800-331-1345 Box 70 Scott Depot, WV 25560-0070 • Fax: 304-757-7305 E-mail:
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Calendar of Events April 18-21 — Boiler Operator (Level I) Training Seminar, Garden City, Kansas. Call (620) 271-0037 or visit www.boilerlicense.com. 21 — Process Heating Systems Management Workshop, Danville, Va. Call (276) 666-8890, ext. 221, or visit www.eere.energy.gov/industry. 26-29 — Infrared Thermography Training Course (Level II), Atlanta. Call (978) 901-8405 or visit www.infraredtraining.com.
or visit www.convertingschool.com. 10-13 — International Conference on Thermal Treatment Technologies, co-located with Hazardous Waste Combustors Meeting (IT3/HWC), Jacksonville, Fla. Hosted by Air & Waste Management Association. Call (412) 904-6008 or visit www.awma.org/IT32011/.
May
10-12 — Semicon Singapore, Singapore. Hosted by Semiconductor Equipment and Materials International (SEMI). Call 65 6391 9513; e-mail
[email protected] or visit www.semiconsingapore.org.
1-5 — Antec 2011, Hynes Convention Center, Boston, Mass. Hosted by Society of Plastics Engineers (SPE). Call (203) 775-0471 or visit www.4spe.org/ conferences/antec-2011.
11 — Process Heating Systems Management Workshop, Downey, Calif. Call (562) 803-7570 or visit www.eere.energy.gov/industry.
2-3 — Process Burner Fundamentals Seminar, Tulsa, Okla. Call (918) 234-5710 or visit www.johnzink.com. 2-3 — Process Burner Operator Training Seminar, Tulsa, Okla. Call (918) 234-5710 or visit www.johnzink.com. 2-3 — Advanced Process Burners Seminar, Tulsa, Okla. Call (918) 234-5710 or visit www.johnzink.com. 6 — Fired Heater Resource Management: Advanced Operation Seminar, Tulsa, Okla. Call (918) 234-5710 or visit www.johnzink.com. 9-12 — American Filtration and Separations Society (AFS) Conference, Holiday Inn Hurstbourne, Louisville, Ky. Call (612) 861-1277 or visit www.afssociety.org. 10 — Steam Systems Management Workshop, Ann Arbor, Mich. Call (763) 350-9397 or visit www.eere.energy.gov/industry. 10-11 — Web Handling and Converting Seminar, Brussels, Belgium. Hosted by AIMCAL. Call (803) 802-7820
12-18 — Interpack 2011, Düsseldorf Fairgrounds, Düsseldorf, Germany. Call 211 4560-900 or visit www.interpack.com. 12-13 — Optimizing Extrusion-Based Lamination and Coating Technology Seminar, Philadelphia, Pa. Hosted by AIMCAL. Call (803) 802-7820 or visit www.convertingschool.com. 16-19 — Boiler Operator (Level I) Training Seminar, Garden City, Kansas. Hosted by Kansas Industrial Technical School (Garden City Ammonia Program). Call (620) 271-0037 or www.boilerlicense.com. 17-20 — Chinaplas 2011, Guangzhou, China. Visit www.chinaplasonline.com. 17-19 — Eastec, Eastern States Exposition Hall, West Springfield, Mass. Hosted by Society of Manufacturing Engineers. Call (800) 733-4763 or visit www.sme.org/eastec. 24 — Fan Systems Management Workshop, Nashville, Tenn. Call (615) 232-6815 or visit www.eere.energy.gov/industry.
Because we deliver your order on time Short lead times and on-time delivery are just two of the ways that Despatch Industries keeps customers on the fast track to success. We also provide on-site training, installation and start up. With a global network of service and support technicians we are there when you need us to help keep you up and running.
INSPIRED INNOVATION
Thermal Processing Technology
phone: 1-952-469-5424
[email protected] www.despatch.com © 2011 Despatch Industries. All rights reserved.
Ovens
Making the
RIGHT CHOICE By Michael Jameson, JPW Design & Manufacturing Inc.
W
hether it is time to replace an existing industrial batch oven, upgrade a process with a new oven or set up an entirely new process that requires an industrial batch oven, there are numerous questions that may arise about how to put together the justification for a capital expenditure.
Learn how to select the proper equipment for your heat processing requirements.
If you’re at a loss as to where to start, or if you just want a framework to follow, this article will help identify the criteria to consider.
Starting the Search Some of the basic questions revolve around the oven size, operating temperature, fuel source, available utilities, airflow pattern, instrumentation and lead time. As a general rule, these are the first questions asked and answered, but they are only the beginning of a critical exchange of information between you and the vendor. Ultimately, it is the communication between you and your ven-
dor that will lead to the proper selection of equipment for your process needs. Oven Size. Oven size is always a fascinating subject as it pertains to the process. Some feel the oven should be large enough to handle future business opportunities, and others want just enough space to handle current requirements. Usually, the project budget helps dictate how far you can go with size. Overall though, the size should be related directly to the process needs. Future business is an unknown, and investing in an unknown future revenue stream is risky. Discuss your needs with the oven supplier to arrive at a size that will do the job. When selecting the oven size, remember to discuss any building restrictions that may pose an issue. Building doorways and ceiling heights are the most common issues that can affect how the oven is designed. Operating Temperature. The required operating temperature has an effect on oven construction. There is a common belief that if you need a 475°F (246°C) operating temperature, then you should purchase a 650°F (343°C) unit. There are pros and cons to this theory. Discussing your particular need with your oven vendor will result in a selection that will meet your processing requirements. As a general rule, the higher the temperature, the higher the cost. Fuel Source. The fuel source for the oven can be electricity, natural gas, propane or steam. The first three are the most common. Typically, oven size guides the fuel source selection. Large ovens are cost effective on natural gas or propane This electric, high temperature, inert gas oven has an automated cooling jacket for bright annealing.
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Ovens Made for processing solvents, this gasfired batch oven offers combination airflow from sides to top.
often are the most cost effective for large ovens while electricity is more cost effective for smaller or low temperature ovens. In some processes, only electricity can be used. Have your oven supplier discuss the fuel source differences and the relative operating costs for your area to determine a cost-effective solution. Utilities. Equally important are the available utilities at your plant. Voltage and phase are required whether you are buying a gas oven or an electric oven. Knowing which utilities are available can help determine if you have the proper utilities in place to operate the equipment. The lack of utilities may add to your cost justification if a new gas line or electrical service is required but not identified up front. Airflow. The airflow pattern inside the oven can make your life easy or difficult. Selecting from combination, compound horizontal, straight horizontal, vertical up or vertical down is truly determined by how you load the oven, taking into consideration the parts’ shape and size. For example, it would be a mistake to load a large stator into a straight horizontal oven, where one leading edge of hot air enters the chamber on the right and returns on the left. The hot air will transfer the energy to the right side of the part first, curing it faster than the left side. The proper selection for this example would be combination or compound horizontal with two leading edges of hot air entering the chamber from the left and right side and returning through the top or rear of the oven. Take airflow into consideration and discuss it with your sales engineer. Instrumentation. Instrumentation is an important topic when selecting a control package for the oven. Controllers range from single setpoint to profiling, and they can be packaged with a recording option or stand alone. Recording devices come in
Aging ovens are used to accelerate the aging process or expose the product to real-life conditions through simulation. This gas-fired aging oven includes a vertical lift door.
paper or paperless, with many options. The right choices can only be made by using the correct information about the process you are performing. Take time to select the control package that will get the job done and again, discuss the options with your sales engineer. Lead time only can be established once the oven is selected completely and workload schedules for the supplier can be
reviewed. This is a variable that is constantly changing. The one thing that I have learned over the years is that everyone wants it faster than it can be built.
Specific Process Requirements Now that you have your size, temperature, fuel source and other basic needs selected, it is time to gather additional information pertaining to your specific process needs. Paint curing, solvent venting, inert gas processing, composite curing, drying, aging and annealing are a short list of some of these specific processes. Some examples will be used to help you understand the requirements that are crucial to selecting the right oven for your application. For instance, solvent venting is a common process requirement for industrial ovens whether you are curing solvent-based paints or varnishes. If your process requires solvent venting, be sure to specify the processing temperature and the amount and type of solvent being processed. The construction of a solvent-venting unit may require pressure-relief panels and an exhaust blower. The unit also will have a purge cycle before allowing the heating circuit to energize. Once you have a material data safety sheet (MSDS) for the material you are processing in the oven, and you www.process-heating.com • A p r i l 2 0 1 1
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Ovens WEB EXCLUSIVE A Working Relationship is Key to a Successful Project The amount of information relative to oven selection is astounding and can be challenging when making a decision on your next oven purchase. READ MORE @ WWW.PROCESS-HEATING.COM
Typically, oven size guides the fuel source selection. The interior of this electric oven is stainless steel.
know the quantity of material being processed per batch, then the oven engineer can help guide you to the proper selection of a solvent-venting oven. Aging is another common process requirement for ovens. Uniformity and instrumentation are two critical details for
these types of units as aging ovens are used to accelerate the aging process or expose the product to real-life conditions through simulation. The process requires the product to get to the target temperature and hold it there uniformly for a specific period of time. Understanding the product load-
Two Coils
ing is important so the work space and airflow pattern are designed to achieve the time to temperature and uniform part temperature specifications required. In some cases, live load testing of the products is required vs. an empty chamber survey. The oven engineer can help select the right equipment and options. PH Mike Jameson is president of JPW Design & Manufacturing Inc., Trout Run, Pa., a manufacturer of custom ovens. For more information, call (570) 995-5025 or visit www.jpwdesign.com.
are Better than One Designed with twin helical coils the General Combustion HYT Series heaters offer the highest efficiency available. The HYT is designed for high temperature applications and its small, compact package makes it the ideal choice for limited space environments and easy installation. The General Combustion HYT is suitable for use with a wide range of fuels and thermal fluids making it the most versatile and efficient heater available. For reliability you can trust and efficiency you can bank on... Call the experts at General Combustion.
HERE’S WHY . . . • • • • • • •
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Highest efficiency available Reduced operating costs Lower stack temperatures Compact construction for easy installation Safe, low-pressure operation No castable refractory Factory tested for optimum performance
A p r i l 2 0 1 1 • Process Heating
5201 N. Orange Blossom Trail, Orlando, FL 32810 • Phone (407)290-6000 • Fax (407) 578-0577
Temperature Sensors
Temperature Sensors
Finding
Your Balance
M
any sources of error exist in process applications, and they can impact the accuracy of a resistance temperature detector (RTD) measurement. The cable incorporated into the sensor can cause a significant error. This article presents an analysis of cable resistance imbalance in three-wire RTDs, with emphasis on the errors that affect the accuracy of the temperature measurement. Guidance and techniques are given for minimizing the magnitude of these errors. RTDs are temperature sensors that use the predictable change in electrical resistance of a material (typically, platinum) with changing temperature. To provide a practical temperature measuring instrument for process applications, it is necessary to attach extension leads to the platinum sensing element. If not properly selected for the application, the number and type of extension leads used can introduce significant errors into the temperature measurement (figure 1). Two-Wire RTD. The two-lead-wire circuit has no mechanism to compensate for or eliminate the resistance of the lead wires from the resistance of the element. The two-lead wire design is only useful when the extension lead resistance is insignificant compared to the sensing element resistance. Two examples of this are applicaAbove: Individual wires are combined to produce three-wire cable. 17
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A p r i l 2 0 1 1 • Process Heating
Errors related to cable resistance imbalance in three-wire RTDs can be minimized. By the Engineering Team, Burns Engineering tions where the leads are very short, or the sensing element resistance is large. Three-Wire RTD. The three-wire configuration provides a compensation loop that can be used to subtract the lead wire resistance from the resistance measurement of the element loop, resulting in a value for just the element resistance. As will be shown, achieving an accurate measurement with this method is predicated on the resistance of each of the leads being exactly equal. Unfortunately, this is seldom the case, and steps must be taken in the design and application of a three-wire sensor to maintain the accuracy of the measurement. Four-Wire RTD. The method that offers the highest accuracy temperature measurement is the true four-wire design. A sensor circuit with two wires on each side of the element allows for a measurement current to be passed across the element via two of the leads and a voltage measurement to be taken through the other two leads. The resistance then is calculated using Ohm’s law (V = IR or R = V/I). The impedance of
the meter taking the voltage measurement is sufficiently high to prevent any current that is flowing through the leads from being used for the voltage measurement. The current flowing through the other two leads and the element is the same throughout the circuit. Measuring the voltage across the element and dividing it by the known current yields just the resistance of the element. Unfortunately, it is not always practical or feasible to use the four-wire method. Instead, often the method selected is the three-wire method.
Three-Wire Measurement Theory Essentially, to provide a three-wire temperature measurement, it is necessary to measure the resistance of the element loop and subtract the resistance of the compensation loop. As shown in figure 2, the resistance of the lead wires and element are in series, so: RELEMENT LOOP = RL2 + EELEMENT + RL3 RCOMP LOOP = RL1 + RL2 www.process-heating.com • A p r i l 2 0 1 1
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Temperature Sensors Lead
Wire
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Lead Wire 1
Lead
Wire
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Wire
2
Compensation Loop
Sensing Element
Lead Element Loop
Lead Wire 2
Sensing Element
Supplied Current
Measured Voltage
Lead
Lead Wire 3
Lead Wire 3
Lead 2-Wire Circuit
So RELEMENT LOOP – RCOMP LOOP = (RL2+ RELEMENT + RL3) – (RL1 + RL2 ) Assuming RL1 = RL2 + RL3 Then, the lead resistances cancel out and RELEMENT LOOP – RCOMP LOOP = RELEMENT In practice, however, the theoretical assumption that RL1 = RL2 = RL3 is rarely true. Within any set of wire, there is always some difference in these values. This imbalance results in the residual difference between the three values being included in the measurement of RELEMENT, resulting in an offset in the element resistance and, therefore, in the resulting temperature measured. Typically, the sensor manufacturer will use one lead color for RL3 and another lead color for both RL1 and RL2. (In other words, RL1 and RL2 will be the same color.) If the resistance imbalance is large between RL1 and RL2, then depending on which way these seemingly interchangeable leads are connected to the readout in the field, a significant error can result in the temperature measurement.
Sources of Cable Resistance Imbalance The resistance of a conductor (R) is based on the formula: R = l x L/A 18
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A p r i l 2 0 1 1 • Process Heating
3-Wire Circuit
Sensing Element
4
Wire
4-Wire Circuit
Figure 1. This diagram shows the differences among two-, three- and true four-wire temperature sensor lead wire configurations.
where l is resistivity, a constant for a particular material at a particular temperature (1 ft). L is the length of the conductor (ft). A is the cross-sectional area of the conductor (ft2). As the length increases or the diameter decreases, the resistance of the conductor increases. To maintain flexibility, cables usually are manufactured from multiple drawn strands of thin wire that are twisted together to form a conductor of the correct diameter for the particular wire gauge size. The bare twisted strand conductor then is insulated. Several insulated conductors are twisted together to form the cable, then an insulating, protective jacket is applied over the twisted conductors. Each these cable manufacturing steps involves de-reeling the wire, passing it through a series of tensioning pulleys through the process, and then spooling it back onto another reel before it goes to the next step. This processing of the wire, despite the best efforts of the cable manufacturers, causes the conductors to stretch. The stretching of the cable results in a reduction in cross-sectional area and an increase in cable resistance. From lot to lot, it is difficult to consistently control the stretching. Typically, the conductors that make up the cable come from different production runs. Ultimately, when the different
RL
1
RCOMP LOOP
R L2 RELEMENT RELEMENT LOOP
RL3
Figure 2. In a three-wire circuit, it is necessary to measure the resistance of the element loop and subtract the resistance of the compensation loop.
conductors are brought together to form the cable, they have slightly different crosssectional areas although they are each still within the standard for the gauge size. These slight cross-sectional variations result in an imbalance in their resistances. In addition, in the case of copper conductors, the copper typically is plated with silver or nickel to improve corrosion resistance. The overall resistance of the conductor is a function of the resistivity of the two materials and their corresponding cross-sectional areas. Unfortunately, thickness control in the plating process is difficult. Any variation in the thickness results in a variation in the cross-sectional area. When the resistivity of the plating material is high, this problem is exacerbated. Nickel is a common plating material used for copper conductors and has a
Temperature Sensors much higher resistivity than the copper. So, a variation in thickness of the nickel results in a larger variation in the resistivity of the conductor. Another common plating material for copper is silver, which has a lower resistivity than nickel. Any variation in the thickness of the coating of the silver has much less of an effect on the conductor resistivity compared to what a similar variation in nickel plating would have. Silver plating is not a miracle cure for resistance, however. There are cost, corrosion and temperature constraints that have to be considered when selecting silver rather than nickel. For applications where circuit resistance is not important to the function, the imbalance in the cable’s conductors is not significant enough to cause a problem. The ASTM standards only specify the cross-sectional area of the conductor and the plating thickness. Yet the variation allowed in the standards yields a range in wire resistance greater than the three-wire RTD compensation method can accept. Most cable manufacturers are able to do much better than what the ASTM standards dictate.
Methods to Mitigate Errors from Cable Imbalance Steps can be taken to mitigate the problem of cable imbalance in a three-wire RTD. Typically, some compromise needs to be made in order to reduce the effect of cable imbalance. There are several options. • Switch from a Three-Wire Sensor to a True Four-Wire Sensor. A true fourwire measurement negates any effect of lead wire resistance; thus, it will always give a superior measurement. It is not always possible to switch to a four-wire configuration. Sometimes, due to space constraints in the probe, or because the existing control or meter infrastructure is configured for three-wire sensors, the option is not available. • Increase the Cable Gauge. For a threewire measurement, the cable conductor gauge used should be as large as possible. The larger the cable gauge, the lower the resistance and the lower the imbalance in the conductors in the cable. Unfortunately, space constraints inside
the RTD may not allow for a larger cable size in all applications. Even with a larger cable, there will be a cable length at which the possible cable resistance imbalance will result in the sensor being out of its accuracy tolerance. • Splice to a Large Cable Outside the RTD. If space constraints inside the RTD prevent users from incorporating a larger cable size, then a larger cable can be spliced to the small cable outside of the sensor. One drawback to this approach is that in the area of the splice, the cable will be stiffer and have a slightly larger diameter than either of the cables. This may make it difficult to pass the cable through conduit. Also, even with a larger cable gauge in the circuit, there is still a cable length at which the possible cable resistance imbalance will result in the sensor being out of its accuracy tolerance. • Resistance Trim the Cable and Fix the Length. The cable can be balanced by adding a compensation resistance to the appropriate conductors in the cable. Typically, the compensation resistance is added near the end of the cable to keep it away from process temperatures. To maintain the accuracy of the temperature sensor, it is important that the cable is not cut during installation as this will physically remove the compensation resistance and return the cable to its original unbalanced state. • Switch to a Silver-Plated Copper Cable. Switching from a nickel-plated copper to a silver-plated copper cable will allow for longer cable lengths. Unfortunately, silver has a lower temperature rating and does not do particularly well in moist environments.
A four-wire cable design offers the highest accuracy for temperature measurement.
In conclusion, a high accuracy temperature measurement requires a true four-wire sensor. When the application will not allow this, a three-wire sensor can be used, but the end user should be aware of how the accuracy is potentially being affected by the three-wire circuitry. Some probe manufacturers do not address the issue of degradation of measurement accuracy with reduced cable gauges or longer cable lengths. However, the cable imbalance issue is always present. By taking into consideration the effects of cable imbalance at the time that a threewire sensor is specified, and by carefully evaluating and selecting one of the techniques to reduce the effect of cable resistance imbalance, it is possible to produce a three-wire measurement probe that will provide a temperature measurement at the needed accuracy. PH This article was written by the engineering team at Burns Engineering, Minnetonka, Minn., a manufacturer of RTDs, thermowells and temperature transmitters, among other temperature measurement products. For more information, call (800) 328-3871 or visit www.burnsengineering.com.
WEB EXCLUSIVE Common Sources There are a number of errors typically made during RTD selection and installation. READ MORE @ WWW.PROCESS-HEATING.COM
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Equipment Overview Boilers
Fulton Companies www.fulton.com Hurst Boiler & Welding Co. Inc. www.hurstboiler.com Miura North America www.miuraboiler.com Parker Boiler Co. www.parkerboiler.com Acme Engineering Products Inc. Ajax Boiler Inc. Babcock & Wilcox Co. Bryan Steam Clayton Industries Cleaver-Brooks Inc. Columbia Boiler Co. Halgo Power Inc. Heat Exchanger Applied Technology Indeck Power Equipment Lattner Boiler Co. Nationwide Boiler Inc. Precision Boilers Reimers Electra Steam Inc. Rentech Boiler Systems Inc. S.T. Johnson Co. Sussman Electric Boilers Teaford Co. Triad Boiler Systems Inc. Unilux Advanced Mfg. LLC Vapor Power Intl. Victory Energy Operations LLC Wabash Power Equipment Co.
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Propane
Natural Gas
Light Oil
Heavy Oil
Electricity
Dual Fuel (combination oil and gas)
Coal
Fuel / Energy Source
Other
Field Erected
Packaged/Skid-Mounted
Other
Tubeless
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Steam Generator
Fire Box
Cast Iron
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Water Tube
Firebox
Fire Tube, Scotch/Scotch Marine/Shell
Type
Fire Tube, Horizontal Return Tubular
You also can conduct your supplier search online! www.process-heating.com Click on Equipment Overviews, then on boilers.
Coil-Type
Courtesy of Hurst Boiler & Welding Co. Inc.
Used for generating steam for power, processing or space heating, or for producing hot water to heat products or a hot water supply, a boiler delivers steam or hot fluid to the end use point at the desired pressure and temperature. Consisting of a closed vessel in which water or other fluids are heated under pressure, the boiler transmits heat from an external combustion source to a fluid contained within the tubes in the boiler shell. The steam or hot fluid is then circulated out of the boiler for use in various process or heating applications. A safety valve is required to prevent overpressurization and possible explosion of a boiler.
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Manufacturers listed in this Equipment Overview responded to a special mailing by Process Heating and do not necessarily represent the entire industrial process boiler market. To be included in future listings, contact Linda Becker at (847) 405-4020 or e-mail
[email protected].
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Pulp/Paper/Forest Products/Converting
Plastics/Rubber
Pharmaceutical
Packaging/Printing
Food Processing
Finishing
Ethanol/Biodiesel Fuels
Electronics
Chemical/Petrochemical
Industries Served
Other
Low NOX Burners
Water Conditioner/Treater
External Heater Unit (to pre-heat water)
Economizer/Heat Recovery System
Deaerator
Condensate Return System
Atmospheric Feedwater Receiver
Greater Than 1,000 psig
Auxiliary Systems Offered
501 to 1,000 psig
301 to 500 psig
201 to 300 psig
16 to 150 psig
Less Than 15 psig
Greater Than 1,000 KW
501 to 1,000 KW
Design Pressure
301 to 500 KW
200 to 300 KW
101 to 200 KW
51 to 100 KW
26 to 50 KW
11 to 25 KW
Less Than 10 KW
601+
Kilowatt Rating
600 | 20,085,000 | 20,700
501 | 16,770,975 | 17,285
500 | 16,737,500 | 17,250
301 | 10,075,975 | 10,385
300 | 10,042,500 | 10,350
201 | 6,728,475 | 6,935
200 | 6,695,000 | 6,900
101 | 3,380,975 | 3,485
<100 | 3,347,500 | 3,450
Rating (Provided in BHP | BTU/hr | lb/hr of Steam)
capabilities: You set the criteria and let the search engine work for you. Hyperlinks take you to some manufacturers’ web sites. If you need more information than what we have specified here and on our website, and you would like to talk to a manufacturer immediately, call or e-mail editor Linda Becker for the contact information you need: (847) 405-4020 or e-mail
[email protected].
151 to 200 psig
Once you know that you need a boiler, how do you find a supplier? One source is Process Heating’s annual Equipment Overview on Boilers. This matrix, available in print and online at www.process-heating.com, will give you a head start on finding manufacturers with experience with your process. You also can conduct your search for a boiler at www.process-heating.com. The online version includes advanced search
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Heaters
A Combo By Bob Narang, Radiant Energy Oven selection and design can have a major impact on production quality and efficiency. This combination infrared and convection dryer helped the manufacturer of nonwoven material properly cure a e ccoating without overheating the substrate.
Combining infrared and convection technologies solves a challenging drying application.
S
ales of a new nonwoven felt product used in the manufacture of electronic components grew exponentially for a processor of the material. The nonwoven felt is used in all kinds of electronic devices for thermal and electrical insulation. Devices like laptop computers and smart phones, which increase the number of features while decreasing in size, present challenges that this nonwoven felt insulation is designed to meet. While increasing sales are always a good thing, the processor’s existing coating line was severely limited in its production capacity, primarily due to an inadequate dryer. The company scrambled to put a new coating line in place with a more efficient dryer in an effort to meet the
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increasing demand for the nonwoven felt. The challenge was to come up with a process that would increase production while maintaining the necessary high level of product quality. The existing line dryer required five minutes to dry and cure the coating. However, the higher line speed the processor required would not allow a five-minute residence time due to space limitations. Drying a Saturated Web. Made from various materials, the nonwoven felt is saturated with a water-based coating containing 50 to 60 percent solids. The web is unwound from a roll with proper tensioning for consistent pick up of coating. The coating is applied by dipping the felt into a coating pan, and the excess is squeezed out by passing the web through a set of
p precision rollers exerting controlled press sure. The amount of wet coating pickup is a almost 10 times the weight of the substrate. Faster Line Speed with Sufficient Drying. Having so much wet coating creD a a drying challenge because the coating ated c could drip from the saturated web while in t dryer. If heaters were installed on the the bottom, the coating might fall onto them. The processor first evaluated a convection dryer, which turned out to be too long for the desired line speed. Significant space constraints in the factory building further ruled the convection-only option out. The material processor also looked into an infrared dryer, which would be quite short in length for the proposed process. However, the dryer supplier contacted did not have much experience with the customer’s end product so the comfort level was not there. Next, the nonwovens manufacturer contact Radiant Energy Systems, and the heat processing equipment maker invited the nonwovens manufacturer into its manufacturing facility to run tests on a pilot line. Due to the space constraints, initial drying tests were performed using the company’s medium-wavelength combination heaters. These heaters combine infrared and air to dry the web. Although the heaters dried the coating in the available space, two issues arose.
Heaters Rick Luedtke, Radiant Energy System’s engineering manager of air systems. The equipment maker’s process engineering group suggested that hot air dryers could be incorporated at the entrance and exit ends of the dryer to address the concerns. “We realized this was an ideal application for a combination dryer,” Luedtke says. The team retooled and set up a short hot air section right next to the coater. It also added a somewhat longer hot air section after the infrared. The tests were re-run using the combination dryer, with encouraging results. The product dried and the coating cured in less than 2.5 min. In the 15' infrared-air heater section, the fast response combination infrared and convection heaters are mounted above and below the web, which is supported on nonstick, plasma-coated driven rolls.
• When the saturated web came out of the water, there was some dripping. The companies were concerned that the bottom heater might get covered with coating. • On the exit end, when the web was almost dry, the moisture level had to be reduced
below 5 percent to cure the coating. Some spots were overheated because the nonwoven web is somewhat uneven in density. “We tried multiple zones, which helped, but the two problems persisted,” says
The Final Solution A solution was found by using a short (3') convection heating section to provide enough heat into the coating to increase its viscosity, so it would not drip. The coating had to be dry enough so that it did not pick off on the idlers that were supporting the web. The heated air was applied to both sides of the web to raise
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Heaters
To get the coating to cure while not overheating the substrate beyond the maximum temperature, a convection zone follows the center infrared air dryer section.
the temperature from approximately 70 to 135°F (21 to 57°C). This was followed by a 15' infrared-air heater section. The fast response combination infrared and convection heaters are mounted above and below the web, which is supported on nonstick, plasma-coated driven rolls. The heaters are staggered to
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WEB EXCLUSIVE
provide extended residence time for gentler drying. Three zones in the machine direction are controlled automatically with an optical pyrometer in each zone looking at the web. Multiple zones provide precise control of the drying rate. When leaving the infrared section, the product reaches a temperature of 185°F (85°C), and most of the moisture is gone. The air is recirculated to conserve energy to minimize the dryer’s carbon footprint as well as to save on energy costs. The coating requires curing but the substrate cannot exceed 220°F (104°C). To get the coating to cure while not overheating the substrate beyond the maximum temperature, another convection zone follows the center infrared air dryer. This final zone is 5' long. The oven design was finalized after the dryer manufacturer ran pilot line trials for the nonwovens manufacturer. Favorable trials gave the customer confidence in selecting a combination dryer to meet the critical needs of this process.
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It’s Time for You to...
The Value of Pilot Line Trials Companies do not have time to buy a piece of capital equipment and spend weeks or months in trial and error striving to optimize their process. READ MORE @ WWW.PROCESS-HEATING.COM
All controls are managed by a PLC so the processor has live control of the process. Any deviation from the process is alarmed and recorded. Data such as line speed, web tension, nip roll pressure, web temperatures in each of the different zones are logged and help the company meet ISO requirements. PH Bob Narang is president and owner of Radiant Energy Systems Inc., Hawthorne, N.J., a manufacturer of infrared and convection ovens and heaters. For more information, call (800) 4867786 or visit www.radiantenergy.com.
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Save Money Improve Efficiency Reduce Operating Costs Lower Utility Bills
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It’s Time for Your New...
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Thermal Fluid Heater Steam Boiler Medium Temp Process Heaters Heating Medium: Thermal Fluids Temp Range: 350° - 650°F BTUs: 126,000 - 6,250,000
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Available with: Expansion Tanks with Level Controls Distribution/Air Separation Tanks Air-Cooled 650° Pumps Custom Skid Mounts
Steam Boilers: NEVER A COMPROMISE FOR QUALITY OR SAFETY
Parker Boiler Co. 5930 Bandini Blvd. Los Angeles, CA 90040 (323) 727-9800 Fax: (323) 722-2848
[email protected] www.parkerboiler.com 24
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15 to 250 PSI HP: 1.5 to 150 HP
Available with: Feed Systems or DA Tanks Blow Off Tanks Softeners Chemical Feed Systems Custom Skid Mounts
Medium Temp Process Heaters Temp Range: 130° - 400°F BTUs: 300,000 - 6,800,000 Hot Water or Glycol
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All Units Available with: Expansion Tanks with Level Controls Distribution/Air Separation Tanks Air-Cooled 400° Pumps Custom Skid Mounts Natural Gas, #2 Oil, Propane, Combination Fired, Low NOx, or Bio Fuel Firing
All Parker Boilers Use a Flexible Staggered Tube Design with 8 to 10 Pass Flow with a 25-Year Guarantee Against Thermal Shock.
Product Highlights Wondering where to find products beneficial to your process? This department provides a number of new products each month and allows you to easily request more information. Simply call those companies in which you are interested, or visit those companies’ web sites using the published web addresses.
Motor Control and Protection
Oxidizers Ovens Furnaces
electrically heated oven has two independent oven chambers stacked one above the other, each with separate controls, that share a single dampered exhaust system. It weighs 1,180 lb with two internal working spaces of 32 x 18 x 18" and exterior dimensions of 43 x 29 x 45". With a maximum temperature
Three-pole contactors and thermal overload protection relays can be supplied individually or assembled as a single- or three-phase enclosed motor starter. Definite purpose (DP) contactors are offered as one-, two, three- or four-pole devices, 20 to 50 A, for lighting and HVAC control. Electrotech Direct (215) 997-8855 • www.esgllc-usa.com
Food-Grade Heat Transfer System Cleaner Cleaning heat transfer systems in the food industry has meant taking machinery apart and cleaning parts by hand. With the development of DuraClean FG, companies can now run a food-safe cleaner through the system while it is running production. The product is the only heat transfer system cleaner that is safe to use in food-grade applications, says the manufacturer. It functions as a heat transfer fluid and a cleaner that dissolves sludge and fouling from heat transfer systems while they run production, reducing the need for downtime. The formulation is capable of running in systems up to 550°F (288°C). Duratherm Extended Life Fluids (800) 446-4910 www.heat-transfer-fluid.com
Double Oven Does Double Duty Model 49C-650D is offered in NFPA 86 Class A or Class B configurations. The
of 650°F (343°C), the oven can be supplied with a heavy-duty stand. Precision Quincy Corp. (815) 338-2675 www.precisionquincy.com
Custom High Temperature Oven Model PTD is based on the company’s Model PTC, which commonly is used for burn-in and qualification testing of down-hole logging equipment. The custom high temperature oven will be used to cure a coating on tools. The custom oven has a larger chamber size and increased weight capacity. It also has an increased maximum temperature of 650°F (343°C) to meet the conditions of the curing application. Prior to shipping, the manufacturer completed factory testing and the oven achieved ±5.4°F (±3°C) end-to-end uniformity. Despatch Industries (888) 337-7282 • www.despatch.com
¾ Oxidizers RTO Recuperative Catalytic ¾ Ovens & Furnaces Conveyorized Low Temp. & High Temp. Batch
936-273-3300
[email protected] www.epconlp.com www.process-heating.com • A p r i l 2 0 1 1
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Product Highlights Selective Soldering Fixture Selective soldering is employed in applications where a small number of conventional components must be soldered to a high standard on an electronic assembly containing mostly surface-mounted components. It can be difficult to obtain a temperature profile from a product assembly as it passes through the selective soldering process. The assembly moves in both the X and Y directions, so the datalogger must be
co-located with the assembly in an area where space may be limited. Model PA2200A allows manufacturers to measure process stability during selective soldering, both preheat and solder pot performance, with a single datalogging fixture. Datapaq Inc. • (978) 988-9000 • www.datapaq.com
Compact Steam Boiler Tribute has the capability to operate at less than 9 ppm NOX with an advanced boiler control system. The compact boiler utilizes a fiber mesh burner, variable-speed fan and integrated gas train. It provides low emissions combustion with only 4" incoming gas
pressure. Other features include full 4:1 modulation, a stainless steel jacket and the company’s SC-750 advanced boiler control system that shows operators the current boiler status. Fulton (315) 298-5121 • www.fulton.com
Electric Shelf Oven No. 881 has a workspace that measures 68 x 30 x 66". The 250°F (121°C) electric oven has 12 kW installed in Nichrome wire elements. A 1,000-cfm, 1-hp recirculating blower provides horizontal airflow across the load. It also includes a 325-cfm forced exhauster, digitalindicating temperature controller, manual reset excess temperature controller with separate heating element control contactors, and recirculating blower airflow safety switch. Grieve Corp. • (847) 546-8225 www.grievecorp.com 26
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A p r i l 2 0 1 1 • Process Heating
Product Highlights Infrared Heat Tool Model LH115 Hand Glo-Ring is suited for applications such as heat shrinking, plastic tube bending, soldering, adhesive curing, solder performs and butt welding. The infrared heat tool incorporates quartz-encapsulated heating elements that open and close to encircle work pieces with instant radiant heat at temperatures up to 1,500°F (815°C). Radio frequency interference is not generated with the heater and it is suitable for use in clean rooms and testing areas. Eraser Co. Inc. • (800) 724-0594 • www.eraser.com
Programmable Logic Controller Model FA-M3V can be used to control discrete and batch manufacturing processes. Offering high CPU scanning speed, the PLC can scan a 100 K-step program in just 1 msec. With a built-in Ethernet port, it delivers single module processing and eliminates communications overhead, ensuring both higher throughput and a smaller footprint. The PLC provides a login function with three layers of access control. The login history can be archived on an SD card. Yokogawa • (800) 888-6400 • www.yokogawa.com/us
PREVENT BORE SEIZURE Watt-Flex
®
Split-Sheath Cartridge Heaters
Split sheath expands when energized for maximum heat transfer — even in oversized bores! Contracts when de-energized for warranted removability Higher watt densities and operating temperatures Continuous heating coil provides uniform temperature profile, prevents warping, and allows hot tip option Better heat transfer means longer life, lower cost
Energized Watt-Flex
De-energized Watt-Flex
(978) 356-9844
www.daltonelectric.com
Clamp-On Digital Multimeters Series HHM590 includes more than 10 fullfeatured models. All clamp-on meters include a set of safety test leads, a 9 V alkaline battery, and an operator’s manual. The temperature models also include a Type K beaded wire thermocouple. Each multimeter has a GS-Mark EN61010-1 Approval Voltage Category III 600 V. Functions include maximum, data hold, peak and zero. Some models have auto-ranging operation. Omega Engineering Inc. (203) 359-1660 • www.omega.com
Free Literature To request any of these free brochures, use the contact information in the literature item in which you are interested, or consult our ad index for the phone, fax, web and e-mail information.
Gas Fired IR Burners Red-Ray Manufacturing, industry leader in gas fired infrared process heating burners, has new product literature available. These can be ordered free of charge via email to
[email protected]. Red-Ray Manufacturing. http://red-ray.com/
For over 50 years, we have provided Electrical Safety Equipment for the Industry. For complete info, contact us at
[email protected]. Visit our website at www.protectioncontrolsinc.com
www.process-heating.com • A p r i l 2 0 1 1
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PH Classifieds
Send advertising copy to: Process Heating/Attn. Becky McClelland Phone: (412) 306-4355 • Fax: (248) 502-1076 E-mail:
[email protected]
Display Classified Rates: 1X $100 • 3X $95 • 6X $90 • 9X $85 • 12X $80
Equipment for Sale Significantly reduce your drying time
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t: 905-356-1327
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Contact: JOE SALIBA (ext:2058) z KIM IAMARINO (ext:2037) z ANNA ROLFE (ext:2056) Air Radiation Heater
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Locate the industrial equipment, components and services specifically used in applying, transferring, measuring, monitoring and controlling heat in the manufacturing operations that you need! • Search by Company Name or Product Category • Downloadable Product Spec Sheets • Alpha Company Listings • Live Web & Email Links • Product Photos
2011 Buyers Guide Start your search today! Watch for expanded - listings! www.process-heating.com/buyersguide
28 | A p r i l 2 0 1 1 • Process Heating
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Advertising Index
Produced and managed by UBM Canon £{{{Ê7°Ê"Þ«VÊ Û`°ÊUÊ ÃÊ}iiÃ]Ê ÊääÈ{£x{ÊUÊ/i\ÊΣäÉ{{x{ÓääÊqÊ>Ý\ÊΣäÉÈ{
Page
Company
Phone
Fax
Web
E-Mail
11
Burns Engineering Inc.
(800) 328-3871
(952) 935-8782
www.burnsengineering.com
[email protected]
27
Dalton Electric Heating Co.
(978) 356-9844
(978) 356-9846
www.daltonelectric.com
[email protected]
8
Davidon Industries Inc.
(401) 737-8380
(401) 737-8395
www.davidonindustries.com
[email protected]
9
Despatch Industries
(952) 469-8278
(952) 469-8206
www.despatch.com
[email protected]
11
Despatch Industries
(952) 469-8278
(952) 469-8206
www.despatch.com
[email protected]
13
Despatch Industries
(952) 469-8278
(952) 469-8206
www.despatch.com
[email protected]
26
Dickow Pump
(800) 880-4442
(770) 933-8846
www.dickow.com
[email protected]
25
Epcon Industrial Systems
(936) 273-3300
(936) 273-4600
www.epconlp.com
[email protected]
23
Fostoria Process Equipment Division TPI (800) 495-4525
(423) 477-5721
www.fostoriaprocessequipment.com
[email protected]
4
Fulton Thermal Corp.
(315) 298-5121
(315) 298-5311
www.fulton.com
[email protected]
16
General Combustion
(407) 290-6000
(407) 578-0577
www.gencor.com
[email protected]
2
Heatec
(800) 235-5200
(423) 821-7673
www.heatec.com
[email protected]
32
Heatec
(800) 235-5200
(423) 821-7673
www.heatec.com
[email protected]
9
Higuchi USA
(310) 792-7051
(469) 241-1902
www.higuchiusa.com
[email protected]
12
Hubbell Electric Heater Co.
(800) 647-3165
(203) 378-3593
www.hubbellheaters.com
[email protected]
8
Hurst Boiler & Welding Co. Inc.
(229) 346-3545
(229) 346-3821
www.hurstboiler.com
[email protected]
10
Miura North America Inc.
(770) 916-1695
(770) 916-1858
www.miuraboiler.com
[email protected]
10
MultiTherm
(800) 225-7440
(610) 408-8365
www.multitherm.com
[email protected]
24
Parker Boiler Co.
(323) 727-9800
(323) 722-2848
www.parkerboiler.com
[email protected]
12
Payne Controls
(800) 331-1345
(304) 757-7305
www.payneng.com
[email protected]
29
Plastec/Canon Communications
(203) 601-3730
(203) 268-5874
www.plastecsouth.com
[email protected]
6
Precision Quincy Corp.
(815) 338-2675
(815) 338-2960
www.precisionquincy.com
[email protected]
31
Process Heating Webinar
(248) 244-1725
(248) 502-1095
webinars.process-heating.com
[email protected]
27
Protection Controls
(847) 674-7676
(847) 674-7009
www.protectioncontrolsinc.com
[email protected]
3
Yokogawa
(770) 251-8700
(281) 340-3838
www.us.yokogawa.com
[email protected]
www.process-heating.com • A p r i l 2 0 1 1
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®
Places & Faces Buhler Aeroglide promoted Frank Rafter to regional director, industrial markets, Americas. For the past six years, he has been a market manager for American industrial projects, working out of Buhler Aeroglide’s Philadelphia office. Also, Paul McKeithan was Rafter promoted to regional director, food and feed markets, Americas. Since 2004, he has been a market manager for pet food, aqua feed and snack foods, working out of the company’s headquarters McKeithan in Raleigh, N.C. St. Louis-based Solutia Inc. has sold its dithiocarbamates and tetrabenzylthiuram disulfide businesses to
Performance Additives Europe GmbH, Hamburg, for $26 million.
Food processor Cargill, Minneapolis, plans to build a corn processing plant in Brazil to produce starches and sweeteners to keep up with that country’s rising customer demand. The new plant will add about 30 percent to Cargill’s existing corncrushing capacity in South America. It will be based in one of three Brazilian states under consideration. A decision on location is expected in early 2011 with the plant scheduled to start operating in 2013.
Alfa Laval, Lund, Sweden, received a $7.8 million food-equipment order in India for a vegetable oil plant, which includes separators, mixers and heat exchangers. According to the company, the project is India’s first complete, integrated edible-oil complex for refining different types of crude oils, in this case sunflower and soya bean, into high quality oils. Delivery is scheduled for 2011.
PUBLISHING STAFF Senior Group Publisher, Manufacturing Group TOM ESPOSITO • (610) 436-4220 ext. 8530 Group Publisher • DOUG GLENN (412) 306-4351 •
[email protected] Publisher • ANNE ARMEL (847) 405-4043 •
[email protected] Associate Publisher and Editor • LINDA BECKER (847) 405-4020 •
[email protected] Contributing Editor • JOY LEPREE ANDERSON (856) 582-9554 •
[email protected] Art Director • COURTNEY FATHERS (248) 244-1292 •
[email protected] Production Manager • BETH MCCLELLAND (412) 306-4354 •
[email protected] Reprint Sales • JILL DEVRIES (248) 244-1726 •
[email protected] E-Media Sales • SUSAN HEINAUER (412) 306-4352 •
[email protected] Classifieds • BECKY MCCLELLAND (412) 306-4355 •
[email protected] Publishing Director, Manufacturing and Gaming Groups JOHN R. SCHREI • (248) 786-1637 Editorial Office 155 N. Pfingsten Road, Suite 205, Deerfield, IL 60015 (847) 405-4000 • FAX (248) 502-1001
ADVERTISING SALES NORTH AMERICA • Sean Meaney • National Sales Manager 530 Humiston Drive • Bay Village, OH 44140 (440) 895-0919 • FAX (248) 502-1051 •
[email protected] NORTH AMERICA • Anne Armel • Publisher 155 N. Pfingsten Road, Suite 205 • Deerfield, IL 60015 (847) 405-4043 • FAX (248) 786-1441 •
[email protected] EUROPE • Carolyn Eychenne • European Sales Representative 7 rue de Maurepas • 78000 Versailles France tel/fax: 011 33 1 30 21 15 62 •
[email protected]
CORPORATE STAFF BNP Media Corporate Office • (248) 244-6400
Chromalox, a manufacturer of electric heat and control products in Pittsburgh, has expanded its sales team in China with the addition of sales representation by Lumax International Corp. Ltd., Taipei. Lumax will provide sales, design and service for customers in process industries across China with offices in Dalian, Beijing and Suzhou in addition to the existing Chromalox office in Shanghai.
Todd Shelden joined Colmac Coil
Manufacturing Inc., Colville, Wash., as a sales engineer specializing in industrial refrigeration and heat transfer coil applications. Also, Bruce Kietzman was named to serve as general manager of Colmac Coil Midwest, Colmac’s manufacturing plant in Paxton, Ill.
Shelden
Kietzman
Chevron Corp., San Ramon, Calif. has announced that Chevron Lubricants will start construction of a lubricants manufacturing facility at the company’s Pascagoula, Miss., refinery. The $1.4 billion Pascagoula Base Oil Project is projected to generate approximately 1,000 jobs over the two years of construction and about 20 permanent positions once the facility is operating.
BASF, headquartered in Iselin, N.J., has started operations at its expanded plant for the production of the biodegradable plastic Ecoflex. Expansion of the existing plant in Ludwigshafen, Germany, will increase production capacity for Ecoflex, a plastic that has the properties of conventional polyethylene but is fully biodegradable under industrial composting conditions.
SINGLE COPY SALES ANN KALB • (248) 244-6499 •
[email protected]
POSTAL LIST RENTAL ROBERT LISKA • (800) 223-2194 x726
[email protected]
E-MAIL LIST RENTAL SHAWN KINGSTON • (800) 409-4443 x828
[email protected]
AUDIENCE DEVELOPMENT Audience Development Coordinator • HAYAT ALI-GHONEIM Corporate Fulfillment Manager • MEGAN NEEL Corporate Audience Audit Manager • CATHERINE M. RONAN
SUBSCRIPTIONS Contact Customer Service at Tel. (847) 763-9534 or Fax (847) 763-9538 or e-mail
[email protected]. Via Web: to subscribe or submit an address change, visit www.process-heating.com and click on subscribe. Via Mail. Send your old address label along with your new address to Process Heating, PO BOX 2146, Skokie, IL 60076.
GET MORE ONLINE Search and read our archives. Every article and column published in Process Heating since 1998 is available online! • • • •
• •
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A p r i l 2 0 1 1 • Process Heating
FREE 60-min. Webinar Register Now at http://webinars.process-heating.com
Setting Up & Troubleshooting Burner Ratio Controls May 3 | 2:00 p.m. EDT Gas trains have two main components - safety and flow controls - that must be set accurately for your combustion system to function. Human error is the biggest reason for annoying shutdowns or the inability of a burner to start up. And setting the fuel-to-air ratio for economical operation, fuel efficiency, system reliability, consistency and less environmental impact is tricky. Lots of things can go wrong. But why? Attend the webinar to learn how to face down and solve problems, set up your burner, and more, such as: • Understanding gas trains
• Troubleshooting your gas train
• Setting up fuel-to-air ratio
• Troubleshooting your safety controls
• Keeping fuel-air ratio where it should be
• Avoiding nuisance shutdowns
• Determining flow controls
• Stopping interference with system startup
• Finding the strengths & weaknesses of your gas train configuration
Advertising Sponsors:
SPEAKER Dick Bennett Combustion Specialist Janus Technology
MODERATOR Linda Becker Editor and Associate Publisher Process Heating Magazine
Register for FREE at http://webinars.process-heating.com Can’t attend live? Register to receive the on-demand version.
Got Maintenance? Plant operators are finding out the advantages of having their heaters serviced by Heatec on a regular basis. There are important benefits of having a contract for our service technicians to do preventative maintenance once or twice a year. An important benefit is safety. Our technicians make sure all limit devices are working properly. Insurance companies usually prefer that specialists, such as Heatec technicians, perform services related to safety. Fuel savings is another important benefit that results from maintenance that includes tuning the burner. Moreover, preventative maintenance usually eliminates unexpected heater
shutdowns at times that interrupt production. Preventative maintenance can usually be done without adversely affecting production schedules. Another benefit is usually a reduction in costs for each service call. This results from lower travel expenses when our technicians can make service calls at other plants in the same area. Moreover, many of our technicians reside in diverse locations that reduce travel to plant sites. Call today to find out what kind of service contract would work best for you.
HEATEC
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