Dukane Ultrasonic Welding News and Information Channel

Happy 38th Birthday "Welder"

noreply@blogger.com (Dukane Ultrasonics) — Wed, 07 Jun 2017 20:50:00 +0000

Yes! You read it right, we recently celebrated the 38th Birthday of our ultrasonic work station built in 1979 to assemble whistles for SERON® Manufacturing. This was the first-time ultrasonic welding was used for manufacturing of whistles. Before this, whistles were assembled using adhesives. Mr. Suren V. Seron, current president and owner of Seron Manufacturing designed these whistles and received a patent in 1981. He chose ultrasonic welding to provide a strong and airtight bond of the whistles for maximum sound generation and to eliminate the concern of aging of adhesives. Patented SERON® P-38® whistles are made of high impact shatterproof ABS plastic and are used internationally by professional referees, coaches, dog trainers, teachers and sports enthusiasts. Underground workers in many industries also use P-38® for personal protection as a safety-sounding device.

Birthday Party Celebrations

Established in 1952 Seron Manufacturing is a family owned business in Joliet, IL. It all started when Mr. Suren V. Seron, was a little boy and like any young boy was playing basketball with neighborhood kids. He accidentally dropped his eyeglasses and broke them. He took the glasses to his dad Dr. Seron, who was a dentist. Instead of just fixing the eyeglasses Dr. Seron thought of having something that would secure the glass on the young boys head during sporting activities. Thus, a new product Glass-Gards® was born, which quickly gained popularity among parents of young kids, schools and people engaged in active sports. Soon Seron Manufacturing became a leading manufacturer and worldwide distributor of safety and industrial supplies including safety eyeglasses, Glass-Gards®, badge holders, lanyards, cords and whistles.

Ultrasonic Welding Workcell

Mr. Suren V. Seron joined his family business in 70s and designed SERON® P-38® whistles. Dukane was his preferred supplier to meet the need for a custom-built ultrasonic welding work-cell. Wendell Harley, who is currently the Custom Engineering Group Leader at Dukane was an Engineer at Dukane in 1979 and was involved in the project. A 20 kHz, six-station rotary part indexing ultrasonic welding work cell was built to meet the production goal of SERON® whistles. Today, SERON® P-38® whistles comes in 15 solid colors and 225 dazzling combinations. These whistles can be customized with specific logo, slogan, company or product name molded in the cap. The work cell is still producing quality whistles, which are supplied worldwide to meet custom wholesale and retail orders.
After 38 years of togetherness, Mr. Seron has personalized the work cell and calls it “Welder”. Keith Day, Sales Engineer at Dukane has been assisting Mr. Seron with any service needs for last 10 years and is now a good friend. He invited Mr. Seron to our headquarters in St. Charles, IL to celebrate 38th Birthday of our ‘Welder’. He accepted the invitation and was excited to meet Wendell Harley and other team members. He shared, “Welder is going strong and producing quality whistles to meet demand.”
We celebrated our quality, customer service, and our passion to take on exceptional projects as an opportunity to provide an outstanding solution. We are looking forward to the celebrate Welder’s 40th Birthday with the whole gang in 2019.

For more information on Dukane's custom built work cells visit http://www.dukane.com/us/PCU_Custom.htm or call 630-797-4900.

Dukane’s ISTeP – New member of Eastman Tritan Medical Toolkit

noreply@blogger.com (Dukane Ultrasonics) — Wed, 29 Mar 2017 15:28:00 +0000

Dukane's Industrial Standard Test Part (ISTeP), a two-piece cylindrical part designed to test various characteristics of different resins and plastic welding processes, is the new addition to the Eastman TritanTM Medical Toolkit. Each application in the Medical Toolkit demonstrates key attributes TritanTM offers in the medical device and packaging markets.

Eastman Tritan^TM Medical Toolkit with Dukane’s ISTeP

Complex medical devices often require secondary operations to complete the assembly or fabrication process of molded or otherwise formed parts, which includes bonding, welding and various other joining methods. TritanTM offers a unique combination of toughness and chemical resistance that makes these molded or formed components well suited to secondary operations that complete the assembly or fabrication process. ISTePs made with TritanTM have been successfully assembled using a variety of welding methods including servo driven ultrasonic welding and the recently developed 2-micron laser welding process that allows joining clear unfilled thermoplastic without the need for any absorbing additives.
ISTeP is replacing the I-beam test part that was previously in the Medical Toolkit. ISTeP’s unique design facilitates a number of testing techniques in which medical device manufacturers can evaluate performance of specific resins, joint designs and welding methods for their particular applications. The ISTeP mold is designed for even filling, preventing warping, sink marks, and ensures consistent wall thickness. The mold design also includes an insert to allow molding of numerous varieties of weld joint designs. Three tabs on the top and three on the bottom portion of the part make it easy to place it into a tensile test fixture. When the welded ISTeP comes apart during the tensile testing, the assembly will do so evenly, avoiding the so-called ‘zipper effect’. An integral port in the lower portion of the part makes it easy to insert an air tube for a static pressure test or burst testing. The ISTeP design also allows for measuring part height before and after welding, determining actual collapse distance. Following video demonstrates ultrasonic welding, pull & leak testing of ISTeP.

The ISTeP injection mold is available upon request from Dukane for firms wanting test parts molded with an alternate material available in Eastman’s family of resins. For more information on Dukane’s ISTeP and other ultrasonic welding products, contact ussales@dukane.com or call 630-797-4900 and for Eastman TritanTM contact tritanexperts@eastman.com or call 423-229-2000.

Dukane presenting at The 46th Annual Ultrasonic Industry Association Symposium

noreply@blogger.com (Dukane Ultrasonics) — Wed, 15 Feb 2017 16:05:00 +0000

The Ultrasonic Industry Association (UIA) is a unique association that brings together manufacturers of ultrasonic equipment, users of ultrasonic equipment, and academicians and researchers involved in ultrasonics. UIA has perfectly managed to blend academic and industrial world interests to boost a wonderful discipline. UIA Symposia are places where one can meet professionals, who practices various non-traditional applications for power ultrasonics. Dukane has been supporting UIA from its early days. Leo Klinstein, VP of Engineering and R&D, has represented Dukane on UIA’s Board since 2005. Annual Symposiums are one of the many ways UIA offers companies access to key influencers in the international ultrasonic community. The 46th Annual UIA Symposium will be held in Dresden, Germany from April 24th-26th of 2017. This event will offer a global focus on the latest advances in ultrasonics in Europe, US and beyond. Leo Klinstein from Dukane, USA and Thomas Daue from Smart Material Corporation /Smart Material GmbH, Germany chair the Symposium. The Monday Medical session chairs are Jay Sheehan, Integra Life Sciences, US and Klaus Van Jenderka, Physik, Sensorik und Ultraschalltechnik, Germany. The Tuesday Workshop chair is Dominick DeAngelis, Kulicke & Soffa Industries, Inc., US. Poster session chair is Margaret Lucas, University of Glasgow. The Wednesday Industrial session chairs are Leo Klinstein, and Rasmus Lou-Moeller, Meggitt, Denmark.

Presenting Dynamic Hold Capability of Servo-Driven Ultrasonic Welding

Leo Klinstein, will present recent study conducted by him and his team to utilize dynamic hold capability of servo-driven ultrasonic welders during the cooling phase of the ultrasonic welding process. Ultrasonic welding of thermoplastic is widely used by many industries to fuse together two parts in a short time without introducing additional consumables such as fasteners, adhesives, or solvents. Recent development of servo-driven ultrasonic welders, as opposed to pneumatically driven welding machines, introduces unique levels of control throughout the welding cycle. This study focuses on the final phase of the welding process, i.e., the hold cycle, and the benefits that the servo-driven ultrasonic welders can provide to this final phase by controlling both hold distance and the velocity at which this final phase is accomplished.

The ultrasonic welding cycle is divided into four separate phases, contact, heating, melting of the joint detail and cooling or hold phase. Hold phase is critically important for the joint quality. During this phase, the weld is actually formed and intermolecular bonds and final microstructure responsible for the joint strength are established.

Leo’s presentation would investigate effects of the hold phase settings on weld’s quality with the aim to alleviate the lack of scientifically based recommendations in setting the parameters of both hold distance and velocity during this phase. It would present and compare test results of not only several hold distances but also the velocities used to achieve them. Dukane’s servo ultrasonic welding equipment with patented Melt-Match® technology will be demonstrated at the event. Bob Aldaz, Zdenek Vondra and Veronica Pekarska from Dukane will also attend the symposium.

Symposium Exhibitor and Sponsor Information

There are four sponsorship packages available, each with different levels of access to exposure in the Vibrations newsletter, UIA website and more. Here is the complete information about the UIA Sponsorship Opportunities. Once you have decided your level of participation, complete the registration form for Exhibits and Sponsors.

Monitor the performance of your Vibration Welding System by utilizing Dukane's patented 'Q' Factor Technology

noreply@blogger.com (Dukane Ultrasonics) — Thu, 04 Aug 2016 16:45:00 +0000

Dukane’s patented ‘Q' factor technology for Linear Vibration Welders is an algorithm to help users monitor and maintain the quality of a welding system over its lifetime. ‘Q’ factor is calculated using the resonant frequency of the welding head of the vibration welder and the time between which its amplitude reaches its peak and declines to half of its peak amplitude. In other words, ‘Q’ factor determines how many cycles of the resonant frequency does it take for the welding amplitude to decline in half. This is system’s resonance quality factor, which determines how quickly a weld fixture’s amplitude decays. The longer it takes for the weld fixture to decay, the higher is the ‘Q’ factor.

Dukane's 5000 Series Vibration Welder

The Plastic Industry uses linear vibration welders to weld two plastic components, by creating linear oscillatory motion of one part relative to another part. The parts are brought together by force, the oscillatory motion generates heat, which melts the adjacent surfaces of the plastic parts and creates a weld after the parts cool. The vibratory movement of one part relative to another part is generated by two electromagnets positioned between moveable and stationary part of the welder. Both electromagnets apply force along the same coordinate line, but in opposite directions. The electromagnets are energized with a 180-degree phase shift so that when the first electromagnet is energized, the second one is de-energized and vice versa.

HMI Screen showing 'Q' Factor

It is important to maintain the frequency of the energizing cycle at the resonant frequency of the movable mechanical part of the welder. This allows for maximum energy transfer to the parts being welded. Any decrease in the ‘Q’ value would indicate that something has deteriorated in the system and that the maximum energy is not been transferred to the plastic components. A typical value of the Q factor for a vibration welder is between 100 and 260. The higher value indicates a more robust system that runs more efficiently with fewer energy losses and is more reliable. This value is measured and stored in the machine process controller (or HMI) during factory testing. As machine ages, the Q factor is monitored and compared to the original value. A decrease can serve as an early warning of the improper tool installation or machine/tool deterioration.

Vibration welders are key investments for many manufacturers. Therefore, manufacturers seek ways to optimize their use and get better ROI on these machines. One of the ways to do so is to rotate tools on the same machine and weld various plastic assemblies. However, the challenge is to monitor and maintain the quality of tools and their proper installation during tooling changes. Calculating and storing the ‘Q’ value for each tool helps in monitoring proper installation. When a user changes the tool, a new ‘Q ‘value is calculated, which serves as a quantitative measure of the tool quality. Difference between original ‘Q’ value stored at the time of factory testing of the tool and the new calculated ‘Q’ value after installation at plant floor can indicate improper installation.

‘Q’ factor of a welder is a function of the quality of its springs, coils, lamination carriers, drives, and the actual upper tooling. While springs, coils, lamination carriers and drives have good repeatability and tight tolerances (since they are standard components shared among the machines), the upper tooling is unique to every part being welded. Therefore, the quality of the tooling design, manufacturing, and installation can have a significant effect on the overall welder performance.

For more information of Dukane's Vibration Welding technology and products visit http://www.dukane.com/us/PVI_VibeWeld.htm or call 630-797-4900.

New White Paper at SPE Events - A Great Platform for Plastic Industry

noreply@blogger.com (Dukane Ultrasonics) — Thu, 19 May 2016 21:29:00 +0000

iQ Series Servo driven Ultrasonic Welding System
with patented Melt-Match® and Melt-Detect™
features

Dukane is participating at two upcoming SPE (Society of Plastics Engineers) events, ANTEC® and SPE Decorating & Assembly Division Topical Conference of 2016. We are presenting a paper on “Generating Stronger and Reliable Ultrasonically Welded parts by Utilizing Advanced Melt Flow Controls of Servo Driven Ultrasonic Welding Equipment.” Chief Engineer for Advanced Technologies, Dr. Alexander Savitski and Sr. Application Engineer, Mr. Kenneth Holt will represent Dukane at these events.

Attendees will benefit by learning the advanced control capabilities offered by the servo-driven system. Ultrasonic welding of thermoplastics is widely used by many industries to fuse together two parts in a short time without additional consumables. Development of servo-driven ultrasonic welders introduces unique levels of control. This paper pursues previous research and investigates the capabilities of iQ Series Servo driven ultrasonic welders to produce stronger welds. The focus is to develop a more robust and controlled joining process for medical devices that increases the strength and reliability of welds without fully collapsing the joint or creating excessive weld flash.

During a typical ultrasonic welding cycle most of the plastic melting takes place in the energy director body, and its molten material forms a bond. Generating maximum weld strength when using pneumatic welding systems typically requires that the weld distance be set close to the nominal energy director height, so the energy director is completely melted. Failure to achieve full melt often results in lower strength, incomplete welds, and poor appearance of welded assemblies. As the actual height of the energy director varies, there is always a risk that some of the parts with a shorter energy director will have excessive flash, and if the programmed weld distance is reduced to avoid that, then there is a risk of generating non-hermetic welds. This paper investigates the effect of weld velocity profiling on developing a more robust and controlled joining process capable of achieving strong and reliable welds without fully collapsing the joint while minimizing the risk of excessive flash.

Experiments were completed in which the weld velocity was varied, and the resulting strength and appearance of the welds were evaluated against the intense requirements of the medical industry. Analysis of weld cross sections suggests that higher weld strength was associated with a linearly increasing weld velocity profile.

Details and key findings of these experiments will be shared at these events. ANTEC® 2016, produced by the SPE (Society of Plastics Engineers) is the largest, most respected, and well-known technical conference in the plastics industry. This year it will be held in Indianapolis, IN from Mar 23rdth – 25th. Dukane has been a part of ANTEC® for a significant number of years. SPE Decorating & Assembly Division Topical Conference will be held in Franklin, TN from June 5th-7th. TopCon will include more than 20 papers on the latest technologies in plastics decorating and assembly.

Please find the white paper by visiting http://www.dukane.com/us/WP-Servo-driven-ultrasonic-welding.htm or call 630-797-4902 for more info.

A Success Story about Team Work and Tenacity - Vibration Welding Toyota Tonneau Cover

noreply@blogger.com (Dukane Ultrasonics) — Wed, 24 Feb 2016 16:06:00 +0000

Dukane feeling honored and proud to be part of this award winning team for Tonneau cover assembly on the 2016 Toyota Tacoma pickup. This winning team in eleven months designed and created a Tonneau cover that is not only flexible and light weight but also provides the required strength and security to the end user. All these unique features have made the Tonneau cover a winner in Parts Competition in Exterior Trim Category at 2015 SPE TPO Automotive Engineered Polyolefins Conference.

SPE Trophy for the winning team

New Toyota Tonneau cover has a trifold design, which can be easily secured or removed from the vehicle. Thermoplastic polyolefins is injection molded to form the upper and lower panel of these three folds. Injection molding was the choice, to get consistent thin wall and dimensional stability. Further these panels are trimmed for additional weight savings. Aluminum bars, “T” nuts and nut plates are placed on the panels for required strength. All the three panels have more weld area on the right and left side to prevent the use of a crow bar to pick up or pry open the assembly and provides security from theft.

Initially, leading suppliers of Vibration Welding technology from the plastic welding industry, including Dukane, felt that this application was a low frequency weld application. Due to the high cost of the low frequency Vibration Welders and the extra expense required to build the larger tooling, it was evident that using low frequency equipment would be a very expensive way to weld these panels. However, Dukane’s technical experts kept an open mind and tested the application using both high and low frequency Vibration Welders, proving it could be done by a high frequency welder. Finally, Dukane built a standard 240 Hz Dukane Vibration Welding machine and kept the cost to a minimum.

Two versions of the assemblies were designed one for short bed truck and another for long bed truck. Dukane built three panels per version which means six vibration tools to weld the six individual parts. Dukane’s customer Nyloncraft, welds these parts in batches. The quick tool change feature of Dukane’s Vibration Welders allow Nyloncraft to weld all the three panels of bed cover using the same welder. Tools are typically changed in less than ½ an hour much less than the changing of the mold tools.

Inductive part sensing capabilities of Dukane’s Vibration Welders are used to make sure that all aluminum bars, “T” nuts and nut plates are placed securely before welding the upper and lower parts. Dukane’s proprietary HMI software is programmed to look for upto 15 parts before welding the upper and lower molds of the cover panels. There is somewhere between 55 and 70 square inches of weld area on each assembly. Some panels are larger so they are closer to the 70 square inches of weld.

Initial challenges on this project were met with team work, persistence and clear vision. The result is an award winning product that helps Toyota meet stringent CAFÉ (Corporate Average Fuel Economy) standards for mpg of fleet vehicles.

For more information on Dukane's Vibration Welding technology visit http://www.dukane.com/us/PVI_VibeWeld.htm or call 630-797-4902

Intelligent Assembly Solutions for Medical Devices

noreply@blogger.com (Dukane Ultrasonics) — Tue, 30 Jun 2015 20:12:00 +0000

Medical devices are complex by nature and designed to assist in healing the human body. Therefore, these devices have the highest quality standards and are subject to stringent regulations. In addition, staying cost effective and employing sustainable manufacturing practices are emerging needs for Medical Device Manufacturers (MDM). Dukane, as a provider of assembly solutions to MDM industry recognizes these requirements and provides its customers with the most advanced assembly solutions and plastic welding technology. Dukane’s equipment options are designed to provide the best quality welds for the most complex of medical devices and components. Dukane’s welding systems are FDA compliant and offer advance process controls, which increase repeatability, deliver consistent part geometry, and reduce scrap rates. In addition, Dukane collaborates with MDM clients to provide technical expertise in assembly method selection, assistance in joint design, feasibility studies, welding systems validation and calibration.

Dukane’s iQ Series Servo Driven Ultrasonic Welder, with patented Melt-Match® technology, has a proven track-record of delivering quality results in welding medical parts like valves, ports, filters, surgical instruments and implant devices. iQ Servo’s patented process control features like Melt-Detect™ confirms the presence of the molten material in the contact area before prompting the press to initiate downward movement. This is especially important in welding small parts and assemblies, which requires hermetic seal, as it eliminates the risk of deforming the energy director before melt is initiated, which could result in a leak path and “cold welds”.

View this video to understand Dukane's patented Melt-Detect™ feature of iQ Servo Ultrasonic Technology

The Melt-Detect™ also enables a user to accurately establish the necessary amplitude required by specific material properties and part configuration by using welder’s graphical output. This authentic approach for amplitude setting allows the user to apply just the right amount of ultrasonic energy that is needed to initiate the melt, avoiding excessive heating and material degradation in the weld. This is especially important for building filter assemblies, where excessive amplitude is associated with tiny pin-holes occurring in the filter media.

Medical Devices and Components Assembled using Dukane's Welding Technologies

In addition, iQ Servo technology eliminates the variability associated with pneumatic press components resulting in improved process repeatability and accuracy, which results in fewer rejects for manufacturers. The elimination of compressed air in Dukane’s ultrasonic welding systems significantly simplifies equipment installation and lowers manufacturing cost.

Watch Dukane's Laser Welder in action

Dukane’s Laser welding systems are capable to weld clear-to-clear and clear-to-colored parts, including typical tube-to-tube-and tube-to-port assemblies. In general, the laser welding technique is dependent on the upper component being transparent to the laser and having the presence of an absorbing agent in the lower component. This configuration limits the process applicability for manufacturing medical devices when a "clear-to-clear" or a "clear-to-colored" assembly is required. Dukane engineers have successfully overcome this obstacle by integrating a recently developed 2-micron laser. This laser produces a beam which is greatly absorbed by clear polymers and enables a highly controlled melting through the thickness of optically clear parts. This has resulted in a greatly improved and simplified technique for laser welding of clear polymers for the medical device industry, which now can fully capitalize on benefits of this advanced Laser assembly process.

For more information on Dukane’s Welding technology and technical expertise call 630-797-4900 or visit http://www.dukane.com/us/AP_Med.htm

Servo driven Ultrasonic Welding technology provides sophisticated results in assembling Mini Medical Device

noreply@blogger.com (Dukane Ultrasonics) — Wed, 06 May 2015 17:15:00 +0000

A leading medical device manufacturer uses Dukane’s iQ Series Servo Ultrasonic Welding System to produce high-quality results in assembling small, delicate Test Strips. These Test Strips are used to measure a person’s Total Cholesterol, HDL, Glucose and Triglycerides. Assembling small medical devices, like these Test Strips, requires precise, repeatable and consistent process control. The Test Strips are made of two thin layers of Polyethylene Terephthalate (PET) film. Between the two PET layers is a mesh membrane infused with the diagnostic chemical.

Prior to investing in Dukane’s iQ Servo Ultrasonic Welder technology, the biggest challenge for this manufacturer was misalignment of the thin PET films during the assembly process. Scrap rate was more than 30%. The iQ Series Servo Ultrasonic Welding System with patented Melt-Match® technology solved the assembly alignment problems and provided accurate, repeatable and reliable process. By using the digital process control from the iQ Series Servo Ultrasonic Welders, they have produced 20+ million Test Strip assemblies in less than three years while reducing their scrap rate to less than 5%.

iQ Series Servo Ultrasonic Welding System

Multiple parameters are available for defining the weld cycle sequence for iQ Servo systems. For this application, the iQ Servo system is programmed to trigger the weld cycle using minimal force. As each weld cycle is initiated, the ultrasonic horn descends towards the assembly at a fast rate of speed. Then, approximately 1.0 mm above the assembly, the horn slows down to a programmed, controlled speed prior to coming in contact with the Test Strip. This is when the iQ Series Servo Melt-Match® feature is initiated. This is best described as when the system reaches the programmed trigger force value on the Test Strip, the horn’s downward movement stops and the ultrasonics start vibrating the horn to soften the PET material. Next, the system’s load cell detects a programmed drop in force, indicating that parts have begun to melt. At that point the weld cycle downward motion re-initiates to further compress the parts. Part welding continues for a programmed distance or energy value at a determined collapse speed. With the weld speed precisely controlled in addition to using Melt-Detect™, unnecessary force is reduced on the thin film that would otherwise distort it. This, in turn, results in improved weld quality.

In the final stage of the weld cycle, the iQ Servo system also gives the flexibility to program Dynamic and/or Static Hold. Dynamic Hold will have the horn further compress the parts after the ultrasonics has been turned off. Static Hold has the weld horn hold its final end-of-weld position for a given amount of time. In this application, Static Hold has been programmed. This gives the materials enough time to solidify without misalignment. Once the Static Hold time has been completed, the horn then returns to its home (or Top of Stroke) position ready for the next weld cycle. This was the most helpful feature for these thin PET Test Strips.

Another major advantage of using iQ Servo system is the ability to duplicate a known process on multiple iQ Servo Systems without any variation in weld results. In this application, this feature was of major benefit for the manufacturing company. They were able to install multiple iQ Servo Systems for their growing need without investing extra time or effort in fine-tuning the process for each welder.

Dukane’s extensive product line of servo-driven technology and our professional sales and engineering team will collaboratively work with customers to provide the best solution for their given application. For more information on iQ Series Servo Ultrasonic Welder and other Ultrasonic Welding products visit http://www.dukane.com/us/ or call 630-797-4900.

Dukane’s Technical Seminars_ a great opportunity to sharpen your saw and get better results

noreply@blogger.com (Dukane Ultrasonics) — Thu, 09 Apr 2015 15:47:00 +0000

Have you heard the story of the man who is working feverishly to cut down a tree? He has been working hard for hours when a passerby suggests that his work might go faster if he would take a short break to sharpen the saw. “I don’t have time to sharpen the saw,” the man says. I’m too busy sawing!”

Unfortunately, this is often the most prevalent attitude towards training. We are so busy trying to meet production demands, cost targets and quality standards that we simply do not stop and sharpen our saw. With this in mind, Dukane's technical team designed two comprehensive technical seminars to help plastic part manufacturers learn and sharpen their Ultrasonic and Vibration welding skills.

Ultrasonic Technical Seminar_conducted by Ken Holt

The Introduction to Ultrasonic Plastics Assembly seminar is a comprehensive two-day technical forum designed to provide a general understanding of ultrasonic plastics assembly and its capabilities. Participants learn practical theory, principles, and benefits of ultrasonic assembly and how to incorporate ultrasonic welding into their manufacturing processes. The workshops are designed to be very interactive and participatory. Participants are encouraged to bring their specific questions, concerns, and applications for discussion and analysis.

Vibration Welding Seminar_conducted by Ray LaFlamme

The second program Introduction to Vibration Welding is a one-day technical forum designed to provide basics of vibration welding. It also gives an opportunity to understand frequency and amplitude of different machines, part design requirement for the process and typical applications for vibration welding.

Classes are small and interactive; Dukane encourages participants to bring in their specific questions and applications for group discussion. These technical seminars are great opportunities for professionals to learn and catch up on advanced Assembly Technologies, network with industry peers and share mutual experiences to articulate better solutions.

Dukane conducts two In-House Technical Seminars annually in St. Charles, IL and multiple regional seminars to provide local opportunities to customers worldwide. For more information on all Technical Seminars and workshops provided by Dukane, visit this Training page or call training hotline (630) 797-4929.

Reference(s):
The 7 Habits of Highly Effective People by author Stephen R. Covey

Ultrasonic Cutting - Various Food Products

noreply@blogger.com (Dukane Ultrasonics) — Fri, 27 Feb 2015 22:55:00 +0000

Dukane offers high quality ultrasonic food processing and cutting equipment including generators, converters, cutting blades, guillotines and slitters. Over the years Dukane’s Ultrasonic food cutting technology has given the best precision and uniformity to the food industry, worldwide. Dukane offers technology and equipment that is reliable and controllable - and backs it up with unparallel service and support. This video demonstrates Dukane’s Ultrasonic food cutting technology and highlights several benefits in using this technology for food processing and packaging.

Throughout the process, food manufacturers find consistent quality, clean cuts and significantly reduce rejects. It also reduces down time for clean up and increases cutting speed, substantially. For more information on your next food, cutting project visit our webpage http://www.dukane.com/us/PFO_food.htm or call 630-797-4900.

Plastic Welding Technical Tip - Weld them while they are hot

noreply@blogger.com (Dukane Ultrasonics) — Thu, 12 Feb 2015 17:12:00 +0000

Molded parts welded hot off the press will weld differently than if they are allowed to cool. Since these parts are not fully cured, their size and shape can change significantly in the first few minutes out of the molding machine.

Freshly molded parts may also retain quite a bit of heat, which can be beneficial in some welding processes. It’s important to realize that the set up for welding warm parts must be different than that for cold parts. Finished part consistency will suffer otherwise. For instance, polycarbonate is one material which reacts well when warm, for two reasons. First polycarbonate is one of the most thermally conductive of the common thermoplastics. Welding warm polycarbonate eliminates one of the problems in welding this material cold. It is often difficult to retain heat in the joint long enough to accomplish the desired weld. Second, since polycarbonate requires a relatively high temperature to flow, less energy will be required to make it flow if the part is already warm. Stress in the joint area may also be reduced by having the surrounding material somewhat warmer, allowing the weld to cool more slowly.

Of course, not everything behaves like polycarbonates. Materials such as olefins (polypropylene and polyethylene), which are not very stiff and have relatively low thermal conductivity, usually weld better when allowed to cool. On the other hand, hygroscopic materials should almost always be welded while they are still warm to reduce absorption of moisture.

Many factors must be considered in determining whether welding hot off the press is appropriate for a particular assembly. Therefore, it is important to process sample parts using this method to define as many parameters as possible before going into full production.

Dukane’s Contribution in Advance Research and Education to strengthen New Talent in plastic technology:

noreply@blogger.com (Dukane Ultrasonics) — Thu, 08 Jan 2015 15:09:00 +0000

In recent years, reshoring and the resulting skill gap are the two most distinct trends in US manufacturing sector. Some of the cost related reasons pointed by industry experts for reshoring are, increased ocean freight cost, increment in manufacturing wages overseas or changes in exchange rate. Experts also reason that companies want to produce close to demand. Whatever the reason is reshoring is very much the new trend. However, on the other end the problem surfacing and hindering reshoring is lack of skilled workforce in manufacturing industry. In May of 2014, The National Press Club hosted an event entitled “The Manufacturing Skills Gap: How a Shortage of Skilled Workers and Needed Education is Affecting the Economic Recovery,” where speakers cited two worrisome figures: There are approximately 600,000 skilled manufacturing jobs that are currently unfilled in the U.S., and 2.7 million manufacturing workers are expected to retire in the next 10 years. Part of the gap is explained by the overall decline in manufacturing over the last three decades or so. Some blame a shift in educational priorities. To rectify this situation, manufacturers are rolling up their sleeves and contributing to initiatives like education in the area of science, technology, engineering, and mathematics (STEM). Some manufacturers are conducting onsite or offsite training to interest local high school students in manufacturing sector.

Dukane Corporation is also proud to contribute its own share to fill the skill gap by providing upcoming talents with resources that can enhance their education and research activities related to plastic technology. Recently, Dukane’s Intelligent Assembly Solutions division facilitated the donation of iQ Series Pneumatic Ultrasonic Welding Press System to the Department of Technology’s Engineering Technology plastics laboratory at Illinois State University (ISU). This device is an Ultrasonic Press System from Dukane’s iQ Series. Features of this equipment as 100% digitally controlled generator, ultra-rigid press, coupled with the iQ Explorer user-interface provides superior accuracy and ease of use. The generators have new multi-core processor technology that allows them to operate at a processing rate of .5 milliseconds. iQ Explorer’s intuitive touch-screen graphical menu structure incorporates a one-page setup screen that makes welder operation easy to learn and program. Ethernet Connectivity and multiple USB ports are all options for weld and graph data storage. Over 25 programmable upper and lower process limits along with reference, weld graph logic are available for weld diagnostics and process consistency. Future Engineers and researchers at ISU will have this unique opportunity to interact and learn from this technically advanced equipment. Dukane and ISU are hoping to strengthen their relationship further through the development of student and faculty research projects.

Reference(s):
• Reshoring is not just a buzzword, it’s an economically driven correction to a supply chain that had become unbalanced. http://www.ptonline.com/articles/the-truth-about-reshoring
• What Processors are doing to Bridge the Skill Gap, Plastics Technology September 2014 http://www.ptonline.com/articles/what-processors-are-doing-to-bridge-the-skills-gap
• Ten for STEM – Ten developments promoting science & technology learning, Machine Design June 2014 http://machinedesign.com/blog/ten-stem-ten-developments-promoting-science-technology-learning

Dukane’s ISTeP---Gaining Industry Wide Recognition as a Standard Test Part

noreply@blogger.com (Dukane Ultrasonics) — Tue, 28 Oct 2014 19:12:00 +0000

The Plastic Welding industry is well aware of the benefits gained from a better weld strength of any plastic material. Whether we are making and delivering medical equipment or packaging for consumer goods, weld strength is the key to achieve customer satisfaction. Dukane’s Industrial Standard Test Part (ISTeP), initially created to test the capabilities of Dukane’s Ultrasonic Servo-driven welders is gaining industry wide recognition as a standard test part in the Plastic Welding industry.

Excitingly, a global specialty chemical company is using ISTeP to compare the weld strength of different types of plastic resins they produce. The chemical company produces a broad range of advanced materials, additives and functional products, specialty chemicals, and fibers found in items people use every day. They are a world leader in the diverse markets they serve and focus on delivering innovative and technology-based solutions while maintaining their commitment to safety and sustainability.

ISTeP is a two-piece cylindrical part used to test a variety of welded parts’ characteristics. ISTeP’s cylindrical shape allows for Spin weld testing along with Laser and Ultrasonic weld testing and is one of the several advantages it has over the Standard plastic I-beam test part. Following video demonstrates Ultrasonic Welding of Dukane's ISTeP parts using iQ Series Servo Ultrasonic Welder. This video also highlights some of the unique design charecteristics of ISTeP for performing better pull and leak testing.

Additionally, the mold for ISTeP is designed for even filling, which prevents warping and sink marks, and ensures consistent wall thicknesses. The mold design also includes an insert to allow molding of an unlimited number of weld joint designs. Already, the mold has been used to produce a shear joint, a butt joint with a 60-degree energy director, and a butt joint with a 90-degree energy director. However, any joint design can be implemented, easily and quickly. The ISTeP allows for pull testing, pressure testing via a tube opening, and measuring part height before and after welding, determining actual collapse distance.

Each ultrasonic plastic welding method has its distinct advantages. ISTeP can also be used to find which welding equipment, process and feature works best. Features such as Trigger by Power, Static hold or Melt-Match® technology can be evaluated. Dukane’s enhanced iQ Series generators and iQ Explorer II software are available to provide even more versatility and process documentation to make the testing process complete and comprehensive.

ISTeP’s injection mold is available from Dukane for firms wanting test parts molded in their choice of resin. Dukane Corporation, Intelligent Assembly Solutions experts offer experience and expertise for your application. For more information on ISTeP and other ultrasonic welding products please contact Dukane IAS division at 630-797-4900 and visit www.dukane.com/us

Dukane IAS, Exhibiting at Upcoming Trade Shows

noreply@blogger.com (Dukane Ultrasonics) — Tue, 30 Sep 2014 22:01:00 +0000

Fall is here and Team Dukane is ready to show and share the fruits of our innovative welding technology. We are exhibiting at upcoming trade shows and will be demonstrating our advance Ultrasonic Welding solutions.

The Assembly Show Booth #1439:

The Assembly Show gives a unique opportunity to witness new technology and products and interact directly with working equipment and machinery. Suppliers, buyers and users of assembly equipment in manufacturing plants connect, learn, share and explore all things related to “Assembly”. Dukane being a pioneer in providing Intelligent Assembly Solutions is exhibiting at the trade show. We are demonstrating our iQ Series Servo Ultrasonic Welder with Melt-Match® technology at this show. There are several economical and environmental benefits of using Servo over Pneumatic welders. Team Dukane will be highlighting those benefits during our demonstration. ISTeP Dukane’s standard testing part is gaining Industry wide recognition. We will weld the test part at the show and explain how you can use the test part to compare the strength of different Resins.

Join us as our special guest on October 28th – 30th 2014, with a FREE* registration to The ASSEMBLY Show at Donald E. Stephens Convention Center, Rosemont, IL. Use discount code “Dukanefree” when registering online to take part in valuable networking and educational sessions focused exclusively on assembly. This is a one-stop event to experience a resource-rich expo floor with live demonstrations and working machinery of the latest assembly technology, welding equipment and products.

PackExpo International, Booth #8352:

Pack Expo International is a great opportunity to witness advanced packaging solutions. Only PACK EXPO focuses on processing and packaging solutions while at the same time introducing you to technologies and ideas from all different industries. It is the one place you can discover innovations you did not know existed and truly see what is possible.

Dukane provides state of art packaging solutions using Ultrasonic Welding Technology and is exhibiting its OEM iQ Series of Ultrasonic Generators with Sealed Converters for aseptic applications. The compact components allow easy integration into OEM equipment. Applications include package sealing & attachments such as re-sealable zipper, films, spouts, fitments, clamshells, tubes and pouches. Dukane will be demonstrating welding of caps to cartons using iQ Series Servo Ultrasonic Welder with patented Melt-Match® technology. On display will be Dukane’s latest iQ welding systems with integrated Ethernet I/P for ease of integration with automated machinery.

We invite you to register for PACKEXPO held at McCormick Place, Chicago, IL from November 2nd - 5th 2014. Use discount code “76R91” and register online by clicking here. Meet the Dukane team at booth # 8352 and witness great technological advancements in packaging.

MD&M Minneapolis Booth # 1532:

For over 20 years, MD&M Minneapolis has been the trusted resource for what is next in medical design and manufacturing. Regardless of your particular design and development objectives, MD&M offers everything you need to drive your project to the finish line. Dukane being highly involved in designing and implementing packaging and assembly solutions for medical industry exhibits at this show. We will be exhibiting our iQ Series Servo Ultrasonic Welder with patented Melt-Match® technology. Stronger weld strength, tighter standard deviation and a significantly higher process capability (Cpk) are some of the benefits our medical industry customers had received using this technology and we would highlight those in our demonstration. We will also weld our new Industrial Standard Test Part (ISTeP) which is being used by the plastic industry to compare weld strength of different Resins.

Mark your calendar and visit us at Booth# 1532 on October 29th and October 30th, 2014 at Minneapolis Convention Center, Minneapolis, MN. For free registration click here and enter code “invite”.

See you at the show and for more information on Dukane's ultrasonic welder and other products visit http://www.dukane.com/us/default.asp

Using a Buffer Sheet in the Ultrasonic Welding Process

noreply@blogger.com (Dukane Ultrasonics) — Thu, 24 Jul 2014 18:55:00 +0000

Appearances matter, and your reputation may depend on that. These days every edge in making consistently appealing and attractive parts is important. So, here’s where the idea of using a buffer sheet in the ultrasonic welding process comes in.

What is a buffer sheet anyway? Basically it is a thin film – think sandwich bag type material, a heavy-duty clear plastic wrap – positioned between the ultrasonic machined tool (horn) and the part that is being welded.
Material used as the buffer sheet should not be the same as that of the parts being welded. For instance, polyethylene film could be used with ABS plastic parts. Polyethylene film is used in most all cases. Sometimes Mylar is considered as buffer sheet material, but it tends to be pricier.

What does the buffer sheet do? The buffer sheet provides a protective cushion to prevent the part from being marked during the welding process. The buffer sheet helps minimize the effects mold imperfections or variations might have as the ultrasonic horn meets the part. Essentially the buffer sheet fills voids due to contouring where the molded part does not match precisely with the horn. The sheet helps alleviate marking that might be caused by mold imperfections such as sinks and warpage and other variations.

What kinds of parts would benefit? Many kinds of parts will benefit from use of a buffer sheet during the ultrasonic welding process. In general electronics that have high internals cost are good candidates. Examples are parts associated with personal electronics, medical devices, and automotive controls and instrumentation. Consumer goods with high appearance requirements such as appliances can also benefit. Welding painted or decorated parts can also be done with a buffer sheet and reduce the concern of marking those surfaces. Whenever there is a critical need for superior quality appearance, using a buffer sheet when welding makes sense.

Machine Equipped with Film Feeding System

Film Feed Device A cost-effective option that provides a solution to position and dispense buffer sheet material is Dukane’s film feeder at approximately $4, 300*.
A 6” wide by 500’ roll of film costs about $20* or $.04 per foot.
Some advantages in using this film feeder:
• Timing adjustments allow consistent film advance.
• This rugged, long-lasting unit will fit nearly any ultrasonic welder.
• Quality and consistency pay off.
• Higher quality parts reflect positively on company reputation and on sales.
• Positive return on investment.
For more information about Dukane’s film feed system, please go to: http://www.dukane.com/us/PPL_Film_Feeder.htm

Contributor:
Ken Holt, Sr. Application Engineer, Intelligent Assembly Solutions
Dukane Corporation, 2900 Dukane Drive, St. Charles, IL 60174
630-797-4900
www.dukane.com/us

*Pricing as of June 2014, and subject to change without notice.

Dukane Japan at the Medical Device Development & Manufacturing Expo in Osaka, Japan

noreply@blogger.com (Dukane Ultrasonics) — Mon, 14 Oct 2013 19:58:00 +0000

The Dukane Japan team participated for the first time at Manufacturing World Osaka 2013. Dukane had a booth at the 4th annual Medical Device Development & Manufacturing Expo.

Dukane Japan team at the Medical Device Development &
Manufacturing Expo in Osaka, Japan.

The staff in Tokyo is ready to assist with your next project – from concept to build. Services include running tests in the lab with a variety of welders including Dukane iQ servo-controlled ultrasonic welders in 15, 20, 30, 40, and 50 kHz and servo-controlled spin welders, and commissioning welding equipment for launch at customer sites with Dukane’s expert resourcing available for each step of the process.

Pictured in the stand from left to right are
Kunihiko Shinjo, Kohei Tajima, and Sunao Nagashima.

The Dukane Japan Tech Center team has expertise working on projects in various markets, including medical device, automotive, packaging, and electronics. Wherever parts assembly solutions are needed, Dukane can offer its wealth of knowledge combined with an advanced line of hardware and software to meet the most demanding requirements.

Kunihiko Shinjo demonstrating Dukane's iQ Servo Ultrasonic welder.

You are welcome to visit the Dukane Japan Tech Center at First Building 6F, 17, Kanda-Higashi-Matsushita-cho, Chiyoda-ku, Tokyo 101-0042 TEL: +81-3-3525-8301 For more information you can also email Dukane Japan: Japan@dukane.com or the Dukane Japan website at http://www.dukane.jp.

Aesthetic Assembly - The Art to Attractive Bonding

noreply@blogger.com (Dukane Ultrasonics) — Tue, 16 Jul 2013 15:40:00 +0000

Miranda Marcus
Dukane Corporation - Intelligent Assembly Solutions

After carefully molding a beautiful product, nothing is worse than seeing it destroyed during assembly. Every joining process is capable of causing marking, flash, particulate, damage to appendages, or other aesthetic defects. However, with proper part design and processing, a finished weld can be imperceptible or even a cosmetic asset. The art to attractive bonding is specific to each process or type of product. Whether processing parts through ultrasonic, spin, vibration, hot plate, laser welding or thermal staking, methods do exist to improve the appearance of the overall product after bonding.

Welding is a common necessity for a wide variety of industries, including automotive, medical, electronics, and consumer products. Whether there are components that must be securely enclosed or the part geometry is too complex to be processed in one piece, a secondary joining step is often required.

A wide variety of products must have aesthetic welds, or bonds. Packaging, especially clamshells, are probably the most prominent example. Some other demanding cosmetic applications are vehicle headlamps and taillights, spoilers, battery enclosures, medical devices, toys, dishware and utensils, electronics housings, facemasks, fencing, furniture, and filters. For these products, and many others, melt flow must be contained, flash or particulate eliminated, tool marks prevented, and any other part damage eradicated.

The methods for preserving cosmetics are as varied as the welding processes available. Each assembly process can produce its' own variety of decorative debacle. Fortunately, for each potential aesthetic issue, there is a solution.

Ultrasonic Welding

Ultrasonic welding uses piezo-electric ceramics that convert electrical current into mechanical motion. High frequency (15 kHz up to 90 kHz) vibrations are transmitted through the plastic part to the joint where intermolecular stress and strain cause melting of the surface of both parts, and welding. Ultrasonic welding is used for a wide variety of applications including clamshells, electronics housings, medical applications, and fabric welding.

Joint Design,

One of the most common cosmetic defects that result from ultrasonic welding is flash; melted material that is pushed out of the joint at the weld interface. In addition to being unsightly, this flash can also be a functional defect in certain applications. For example, air or water filter housings usually cannot have flash internally.

Fortunately, flash can be easily avoided through proper joint design. Generally, in production, there is balance between weld strength and amount of flash. In order to get greater strength, more collapse of the joint is required, and more flash is produced. Simply adding a flash trap to the part design, however, can allow sufficient strength with no flash. Figure 1 shows some common ultrasonic joints that can effectively hide flash and produce a strong weld.

Figure 1: Ultrasonic Joints that Hide Flash

De-Gating

A second common defect with ultrasonic welding is de-gating of small features in the assembly during the weld. Because ultrasonics depends on high frequency vibration of the parts, there is a chance for cracks to form in areas with sharp corners or small cross-sectional areas. Sometimes these cracks are so severe that small features can be complete sheared off, or de-gated.

There are two main ways to prevent this type of damage. Either increase the radii or cross-section of the troubled area, or decrease the amplitude of the process. However, reducing amplitude often has a negative impact on the weld, as it essentially reduces the energy available to weld the parts. Therefore, whenever possible, it is best to eliminate small or fragile features when ultrasonic welding will be used.

Surface Marking

When welding textured parts, there is a strong possibility that the ultrasonic horn will mar the contact surface. On textured surfaces, there may be shiny places where the texture has been removed during welding. To prevent this occurrence, simply put a layer of thin film between the part and the horn. Figure 2 shows an example of this type of cosmetic flaw.

Figure 2: Ultrasonic Welding can cause damage to the parts texture.

Marking can also occur when the horn leaves a residue on the part, see Figure 3. This is most often seen with aluminum horns or with titanium horns that are welding white parts. Using chrome plated aluminum horns is the best way to prevent this type of problem.

Figure 3: Ultrasonic welding with an aluminum horn can leave residue on the part.

Film &Fabric

As mentioned in the introduction, clamshell packaging is one of the biggest areas where cosmetic assembly is required. Ultrasonic welding is one of the processes most often used for such applications. A wide range of weld patterns have been developed to improve the appearance of such welds. Figure 4 shows some common welding patterns used for clamshells.

Figure 4: Examples of patterns used to weld clamshells

These same patterns can also be used for welding of fabrics, as is often done for shower curtains, plastic bed sheets, or even clothing. In fact, fabrics can be welded using ultrasonics, very similarly to how they can be sewn, using a rotating anvil under a stationary horn that is operated by a foot pedal. An even wider range of attractive patterns can be used for fabric welding; some are shown in Figure 5 below.

Figure 5: Patterns used to weld film or fabric

Spin Welding

Another common welding process is spin welding. In this process, one of the parts is held stationary, and the other is spun at high revolutions per minute to generate frictional heat at the circular joint. While spinning, the parts are pressed together to form a weld. Spin welding is often used to join pipes, insulated cups or bowls, and filter housings, among others.

Joint Design

The biggest drawback, cosmetically, to spin welding is that it generates a significant amount of flash. Unlike ultrasonic welding, the parts are moving during the weld process, meaning that the melt layer is also in motion. Subsequently, more melt must be generated to ensure good contact between the parts and a strong weld. Figure 6 shows an example of the type of flash generated during spin welding.

Figure 6: Spin weld flash

Therefore, for every application where aesthetics is a concern, the part should be designed to hide that melted material, some weld joints that can hide flash are shown in Figure 7. With out-of-round parts, however, it is often not possible to contain the flash simply by using a different joint design. In these instances, a secondary flash removal step is required.

Figure 7: Spin weld joint designs that can hide flash while providing a strong weld.

Particulate

In addition to solid pieces of displaced material, spin welding tends to generate particulate (tiny particles of plastic dust). Most times, this can be blown out after welding, but sometimes it cannot be present at all (as with medical or food industry applications). Reducing the rotational spin welding speed reduces the generation of particulate. Additionally, soft materials like polypropylene tend to produce much more particulate during welding, as shown in Figure 8.

Figure 8: Spin welding particulate

Tooling Marks

Like most other welding processes, there is the possibility of leaving tooling marks on the parts. Typically, this occurs on the upper part when it is not securely held in place using designed driving features. Tooling marks occur when the upper part slips in the tool. When the fixture is made of urethane, this can cause black marks on the parts. When it is made from stainless steel or aluminum, it can leave gouges in the parts, see Figure 9.

Figure 9: Spin welding tooling marks

To avoid this type of marking, it is essential to provide driving features on the part itself. A "driving feature" is simply some type of protrusion or depression on the upper part upon which the upper tool can apply rotational force. In addition, the parts should have relatively consistent external dimensions.

Vibration Welding

Vibration welding is one of the most often used welding processes for large parts, such as vehicle headlamps and taillights, glove boxes, intake manifolds, fencing, and even furniture. In this process, one part is held stationary while the other is vibrated horizontally on top of it at low frequency (120 Hz - 240 Hz) and high amplitude. During this vibration, the upper part is also pressed down on to the lower part to create the weld.

Joint Design

Vibration welding depends on the movement of large amounts of melted material to generate a weld. Therefore, for this process as well, the joint design is critical for flash containment. With the proper design, a strong flash free weld can be achieved consistently. Figure 10 diagrams some joint designs that can produce a strong weld with no flash.

Figure 10: Vibration joint design diagrams

De-Gating

As with ultrasonic welding, the movement of the parts during vibration weld can cause de-gating of small features. The high amplitude used in vibration welding causes excess stress on large projecting features. De-gating is especially likely to occur when the base of the feature has a small cross-sectional area or sharp corners.

Tooling Marks

Vibration welding is similar to spin welding in that driving features on the part are required to prevent tooling marks. In the absence of such features, a knurl pattern may be used to grip the part. The use of a knurl, however, will cause abrasions on the part, as shown in Figure 11.

Figure 11: Vibration welding tools often use knurling to grip the parts.

If such marking is not acceptable a urethane upper tool combined can sometimes be used to prevent scratches on the part. Often, a vacuum must be used with urethane tooling to provide sufficient holding force. Whatever tooling material is used, the parts must still be kept as dimensionally consistent as possible.

Hot Plate Welding

In hot plate welding, the two parts to be joined are pressed against or brought into close proximity of a heated surface to generate a melt layer, then pressed against each other to complete the weld. In this style of welding, the joint may be contoured quite extensively and strong hermetic welds are generally achievable. Nothing can be captured inside the parts, however, as any internal components would be damaged by the hot plate. Hot plate welding is often used for large pipes or tanks.

Joint Design

Although hot plate welding generates a lot of flash, it is the most controlled, good-looking flash of any weld process. The melted material pushed of the joint when the two parts are pressed together forms a very nice rounded line that can almost look as if it was designed to be there, this can be seen in Figure 12. However, if the double line of melt does not suit the application at hand, it can be hidden with a change of joint design.

Figure 12: Hot plate flash can look very controlled and nice

Out-Gassing

One of the unique potential cosmetic issues with hot plate welding is out-gassing. When plastic is heated, it emits gasses that can discolor the parts when they are welded, especially on metalized surfaces. The effects of out-gassing are identified in Figure 13. This can be eliminated by applying a vacuum to one of the parts to extract the fumes before they can cause any discoloration or degradation.

Figure 13: Hot plate out-gassing

Warping

Due to the high heat input used in hot plate welding, the parts can be warped during welding. The best way to prevent this is to use thicker part walls. Excess warping can also be avoided by using vacuums and clamping in the tooling to keep the parts in the correct shape during the weld.

Laser Welding

One of the newest polymer joining processes is laser welding and is growing in popularity, particularly for medical applications. This assembly method uses a focused laser beam to heat the weld joint. The two parts are simultaneously pressed together to create the weld. Laser welds are known for being very clean; flash and particulate free. Laser welding never causes de-gating of features and generally never causes warping. Still, for some components, there is potential for cosmetic defects.

Surface Degradation

If improperly set up, there is a chance that surface degradation will occur during welding. This happens if the top part absorbs too much of the laser energy or if the bottom part absorbs too little. This can be somewhat adjusted for by changing the focal point of the laser, but it is best avoided by choosing the materials with good laser welding properties at the outset.

Burning

The greatest potential for aesthetic flaws in an established process is marring from dirt or dust that is burned by the laser during the weld. Any dust in the path of the laser will absorb the weld energy and cause a disparity in the weld. To prevent this, it is important to maintain the cleanliness of the lens and the weld joint.

Burning can also appear in the process set-up phase as over-welding. An example of over-welding by laser is shown in Figure 14. To resolve this issue, decrease wattage to lessen the laser energy or increase the travel speed of the laser. In some systems, over-welding can be eliminated by adjusting the focus point of the laser so that it is further from the part.

Figure 14: Laser over-welding causes burns at the joint

Thermal Staking

Thermal staking is a method of mechanically bonding two parts by melting and reforming one of the parts to contain the other. Most often, a post on the part with the lower melting temperature is melted and formed into a dome shape to hold in the second part, similar to a rivet. Thermal staking is frequently used to contain circuit boards or to replace screws on consumer products.

Stake Design

The most common cause of unattractive stakes is improper post or tool detail design. It is vital that the staking detail has the same volume as the unformed post. If it is too small, excess material can be pushed out around the base of the stake. If it is too larger, the detail will be only half-formed and uneven in appearance. Figure 15 shows two of the most common staking detail design.

Figure 15: Thermal staking design diagrams

Sticking

Even if the post and staking detail are properly designed, however, there is a chance that the formed dome can be marred if the melted material sticks to the thermal tool. This is especially common with soft materials, like polyethylene. Happily, it can easily be avoided through temperature modulation and the use of post cool. Figure 16 shows the type of stringy wisps of material that can be left behind when the parts sticks to the thermal tool.

Figure 16: Thermal sticking

Conclusion

If an application must be beautiful, then it is best to begin considering the assembly method early in the design process. Most of the common cosmetic defects can be avoided with proper part design. Planning for aesthetic assembly in these early stages will help allow a widened processing window in production and reduce reject rate.

However, if a part is already in production without having planned for the welding process, do not panic. There is plenty that can be done to prevent unsightly flash, marking, or other defects. Figures 17-20 show some examples of attractive welds.

Figure 17: A well-designed ultrasonic joint results in a strong, flash free, weld

Figure 18: An attractive spin weld, free of tool marking, particulate, and flash

Figure 19: A properly designed vibration joint shows no flash zig-zag_with_penny

Figure 20: Laser welding is one of the cleanest joining methods available. Photo courtesy of Leister Corporation.

Figure 21: A nicely formed thermal stake

Assembly Demands Grow for Medical Plastics

noreply@blogger.com (Dukane Ultrasonics) — Wed, 05 Jun 2013 14:52:00 +0000

Published: May 6, 2013
By: Plastics Today

A study done at Value Plastics, a molder of precision molded couplers for medical applications, shows that a servo welder produces hermetic welds with a standard deviation of 0.4% compared to 2.9% when using a pneumatic welder.

Those results were reported last month at ANTEC in Cincinnati, OH by three officials at Dukane Corp., which has been testing potential benefits of its recently developed servo-driven ultrasonic welder.

iQ Series Servo-Driven Ultrasonic Welder
with Melt0Match technology

"These benefits include increased precision and repeatability, increased weld strength, the ability to precisely define velocity control, reduced residual stress in parts, and almost complete control of the process," the three authors reported. "Our most recent experiments have shown that the optimal weld velocity can be calculated and that residual stresses can be further minimized through careful hold phase control."

The authors of the Dukane ANTEC paper are Miranda Marcus, applications engineer; Satish Anantharaman of the Technology Demonstration Center in Tamil Nadu, India; and Bob Aldaz, a senior project engineer.

Dukane developed the iQ series Servo-Driven Ultrasonic Welder with Melt-Match technology in response to a growing call, particularly in the medical market, for more controlled and consistent ultrasonic welding processes as part designs become more complex and requirements escalate. There is also a need for strong, dimensionally consistent parts with good cosmetics.

Weld data can be exported to Excel or Minitab for process optimization analysis.

Experiments at Ohio State University have shown a standard deviation of weld strength of 5.1% when using Dukane's servo-driven ultrasonic welder, compared to 9.4% when using a pneumatic welder.

Original Article from Plastics Today:
http://www.plasticstoday.com/articles/assembly-demands-grow-medical-plastics0506201301

Experiments in Reducing Residual Stress with Dukane’s Servo-Driven Ultrasonic Welder

noreply@blogger.com (Dukane Ultrasonics) — Tue, 30 Apr 2013 13:57:00 +0000

Miranda Marcus & Satish Anantharaman

Even on parts with good weld strength, failure can occur in the field due to residual stresses [A]. With ultrasonic welding, residual stresses are typically in the range of 35 MPa due to the rapid cooling of the small amount of melt [A, B]. Recent experimentation at Turku University of Applied Sciences in Finland have demonstrated that parts welded with a servo welder have significantly less residual stress than parts welded with a pneumatic welder. This research also demonstrated that parts with shear joints retained less residual stress than parts with energy directors [C].

Experimentation
While residual stress due to cooling is a characteristic of the ultrasonic welding process, orientation induced residual stresses are affected by the hold force applied after the weld phase. Control over the hold force could therefore result in reducing orientation induced residual stresses and thereby minimize the overall stress in the part due to welding. In order to test the validity of this theory, molded polycarbonate parts were welded at a variety of hold speeds and distances.
For all the samples the weld speed was 2 mm/s. One part was welded with no hold time. Three parts were welded at a hold speed matching the weld speed (2 mm/s) with varying hold collapse distances. The last three parts were welded to 0.5 mm collapse at half, double, and quadruple the weld speed.

Table 2: Hold phase settings used

After welding, the polycarbonate parts were exposed to various mixtures of Methanol and Ethyl Acetate for three minutes. The parts were examined under the microscope for crazing and cracking due to the solvent exposure [13]. The residual stresses were quantified using the chart developed by GE plastics shown in figure 4. They were then examined for crack formations to determine the level of residual stress at the weld.

Figure 4: Graph showing critical stress levels in Polycarbonate as a function of solution concentration [13]

For these tests, AWS I-Beams with energy directors were used. This was for two reasons. First, previous studies indicated that higher stresses occur in energy director parts thereby allowing a greater range of stress to observe. Second, it is far easier to observe cracks in the energy director parts than in the shear parts due to the part geometry.

Figure 5: Drawing of AWS I-Beam with Energy Director [12]

Results
Some differences in residual stress levels were noted after testing. Crack formation was seen in varying locations and amounts in the parts. For the purpose of this paper, number and location of cracks were not considered, only presence or absence.

Figure 6: Cracks shown in a weld joint after exposure to Methanol and Ethyl Acetate mixture.

The results show that increased hold distance may reduce residual stresses at the weld. Additionally, lower stresses were observed when the hold speed was about double the weld speed. Further investigation into the effect of hold settings on residual stress in the weld joint is merited based on these results.

Table 3: Stress level as determined by crack formation.

References
A. S. Anantharaman and A. Benatar. “Measurement of Residual Stress in Laser Welded Polycarbonate using Photoelasticity” ANTEC 2003.
B. A. Benatar. “Servo-Driven Ultrasonic welding of Semi-crystalline Thermoplastics” 39th Annual Symposium of the Ultrasonic Industry Association. Cambridge, MA. 2010.
C. H. Turunen. “Ultrasonic Welding for Plastics” Bachelor’s Thesis, Turku University of Applied Sciences, Finland. 2011.

Experiments in Velocity Control with Dukane’s Servo-Driven Ultrasonic Welder

noreply@blogger.com (Dukane Ultrasonics) — Thu, 11 Apr 2013 14:21:00 +0000

Miranda Marcus, Satish Anantharaman, & Bob Aldaz

Even before the introduction of Dukane’s servo-driven welder, the need for velocity control was recognized. As Mikell Knights wrote in 2005, “Research has proven that consistency of melting rate has a direct influence on bond strength,” A linear velocity means a steady melt rate which, in turn, creates a homogenous molecular structure and a stronger weld [A].

In past years there has been much effort put into attempting to get consistent velocity control with pneumatic systems [2, 3]. These efforts have been in vain, as it is simply not possible to get precise velocity control with a pneumatic welder [C]. As one writer put it trying to achieve precise speed control with a pneumatic press was “the equivalent of sending a ship on an ocean voyage with a map and a compass from a box of cereal” [B]. Dukane’s servo-driven ultrasonic welder offers clear improvement in process control.

Studies using servo ultrasonic welders have shown that the programmed weld velocity can be directly correlated with weld strength [C, D, E, F]. In a study at The Ohio State University it was shown that by using a defined velocity profile with a slower speed during melt initiation and a faster speed in the middle and end of the weld, strength could be increased with less weld time and reduced surface marking [F]. Dukane has provided a unique new weld control to achieve this initiation of melt before collapsing the weld through the use of the patented “melt detect” feature. This features allows the press to contact the parts and turn on ultrasonic vibration with no vertical movement until a drop in force is detected which indicates that welding has initiated [C].

Experimentation
One of the greatest benefits of servo-driven ultrasonic welding is the ability to program a specific weld velocity. It has often been said of plastic welding that it is more art than science. With the new controls available, this no longer needs to be the case. In this experiment, we made both a finite element model and a finite difference model of a shear joint in a standard AWS I-Beam sample to determine the rate of melt formation and then welded parts at varying weld velocities to determine if the modeled weld velocity could be correlated to the optimum weld velocity through experimental data.

Figure 1: Drawing of AWS I-Beam with Shear Joint [12]

For the Finite Element Analysis, a ProE 3D CAD model was made of the AWS I-Beam part consisting of three individual pieces, the top part, the bottom part, and the shear joint. The shear joint was assigned a heat generation rate based on the following equation: Q = πƒ•ε²•Eloss, Where ε² is the strain amplitude at the shear joint calculated by amplitude divided by length and Eloss is the loss modulus of the material (Nylon 6,6 in this case).

Figure 2: Screenshots of finite element analysis (modeling half of the part)

The finite difference analysis was performed with the same initial steps. However, instead of using a CAD model, Mathcad was used for the 1D analysis.

Figure 3: Screenshot of 1D finite difference analysis

Both methods were used to produce a graph of temperature vs. distance at discrete 0.05 second intervals. The width of the melt layer was determined based on attainment of the melting temperature (354 °C). From this, the rate of melt formation was calculated.

Table 1: Calculated melt formation rates for Finite Element
Analysis (FEA) and Finite Difference Analysis (FDA).

After determining the theoretical ideal welding velocity to match the melt formation, five parts were welded at each of five velocities: 0.5 mm/s, 2 mm/s, 4 mm/s, 6 mm/s, and 10 mm/s. After the parts were welded, they were cut in half and each half was pull tested to determine the relative weld strength.

Results
After tensile testing, a clear relationship was observed between weld speed and strength, as expected. Most interesting was that the maximum weld strength was observed at 4 mm/s and 6 mm/s which were modeled to be the initial melt formation rates in the part.

Another interesting result was that the toughness of the weld, as measured by elongation, followed the same general pattern as the weld strength, although the difference between weld speeds was not as distinct.

Figure 5: Weld strength and elongation as a function of weld speed

References
A. M. Knights. “Graphical Analysis Helps Find and Fix Ultrasonic Welding Problems” Plastics Technology. Sept 2005.
B. T. Kirkland. “Ultrasonic Welding: The Need for Speed Control” Plastics Decorating. July/August, 2012.
C. S. T. Flowers. “Servo-Driven Ultrasonic Welding of Biocomposites” ANTEC 2012.
D. A. Benatar. “Servo-Driven Ultrasonic welding of Semi-crystalline Thermoplastics” 39th Annual Symposium of the Ultrasonic Industry Association. Cambridge, MA. 2010.
E. M. Marcus, P. Golko, S. Lester, L. Klinstein. “Comparison of Servo-Driven Ultrasonic Welder to Standard Pneumatic Ultrasonic Welder” ANTEC 2009.
F. A. Mokhtarzadeh and A. Benatar. “Comparison of Servo and Pneumatic Ultrasonic Welding of HDPE Shear Joints” ANTEC 2011.

Tech Center Shines!

noreply@blogger.com (Dukane Ultrasonics) — Fri, 15 Mar 2013 14:52:00 +0000

We invite you to come see us at Dukane’s Automotive Technical Center in Wixom, Michigan. The place has taken on a new, refreshing look, and really shines!

A recent upgrade to the facility coincides with some milestones for the company: 5 years for the Wixom Center, and 90 years for Dukane Corporation, St. Charles, Illinois. What a great way to salute the firm that has been providing innovative assembly solutions through its outstanding equipment and worldwide network of highly qualified experts.

At Wixom there’s a welding lab showcasing the latest Dukane technology in its full line of welders. We have the most recent additions, the iQ Series ultrasonic press systems, and hand probe units with their best-in-class ergonomics. You will also find systems that demonstrate Servo Spin welding, Thermo Press for heat staking or inserting, and Vibration Welding. Especially impressive is our Model VWB 4700 vibration welder, which is capable of handling a large range of part sizes.


From left to right - Thermal Press, iQ ultrasonic Hand Probe system, Dual Servo Spin Welder, iQ ES pnuematic 20 kHz Ultrasonic Press System

Model VWB 4700 vibration welder capable
of handling a large range of part sizes.

The lab itself features an acoustical tile ceiling to keep things quieter, and the environment is temperature controlled, so the lab can be easily used year round.

The staff in Michigan is ready to assist with your next project – from concept to build. Services include commissioning welding equipment for launch at customer sites with Dukane’s expert resourcing available for each step of the process.

The Tech Center offers its expertise not only for automotive applications, but for other markets as well. Wherever parts assembly solutions are needed, Dukane can offer its wealth of knowledge combined with an advanced line of hardware and software to meet the most demanding requirements.
Stop by the Tech Center, 47757 West Road, Suite C101, Wixom, Michigan.

Advantages of Servo Driven Ultrasonic Welder

noreply@blogger.com (Dukane Ultrasonics) — Fri, 22 Feb 2013 16:04:00 +0000

Miranda Marcus

Ultrasonic welding is one of the most widely used processes for bonding polymers, valued for its speed, flexibility, and low cost. Recently, there has been a call for more controlled and consistent ultrasonic welding processes, as part designs become more complex and requirements more stringent. There is also a need for strong, dimensionally consistent parts that show good cosmetics. The process used to meet these increasing demands must be consistent and repeatable over time. Dukane has worked to meet this demand through the development of a new iQ series Servo-Driven Ultrasonic Welder with Melt-Match® technology.

In the ultrasonic welding process, there are three fundamental process variables that have a direct effect on weld quality: amplitude, force, and duration. The first of these parameters, amplitude, has long been controlled through frequency selection, horn-booster design and modulation of the electrical input to the transducer. The second of these parameters, duration, could only be controlled only by setting a specific weld time for 50 years. In 1988 this was revolutionized by Dukane’s development of welding by distance, thus allowing greatly improved troubleshooting and process control.

Recently, a new precise method of force control has been introduced with Dukane’s servo-driven ultrasonic welder in 2009. This new development allows complete control of the third parameter that defines ultrasonic welding, force. In recent years, there has been a plethora of research conducted with the new servo-driven ultrasonic welder. Each of these experimental studies has demonstrated unique benefits of using servo-driven ultrasonic welders.

We are entering an exciting new age of ultrasonic welding. Dukane’s servo-driven ultrasonic welder offers greater process control than was every possible before which will allow welding of ever more complex and demanding applications.

Process Control

It has long been known that better process control leads to improved part quality and consistency. As Robert Leaversuch noted in 2002, “in automotive, medical, and other demanding sectors, use of advanced controls is critical to meeting strict quality requirements” [G]. In this, as so much else, servo welders are at the “top of the process-capability food chain” [F]. Because all of the process settings are controlled electronically, it is easy to switch between welders [I]. Also, this greatly simplifies the calibration and validation processes. Dukane’s servo-driven ultrasonic welder further eases process optimization by allowing all the weld data to be exported in formats that can easily be imported to excel or Minitab for analysis [E]. The data produced by the generator in the form of graphs or weld data is very useful for process optimization and troubleshooting [H]. Simply said, servo welders “take control of the process away from the plastic” [F].

Precision and Repeatability

The servo welder has been shown to consistently produce more repeatable results through multiple methods of evaluation. A study done at Value Plastics, a manufacturer of precision molded couplers and components for various industries including medical, showed that the servo welder produced much more consistently hermetic welds (as measured using pressure decay) with a standard deviation of 0.4% compared to 2.9% when using a pneumatic welder [A].

15 kHz Ultrasonic Servo Press System

The servo-driven ultrasonic welder also offers “excellent repeatability of collapse distance from part to part” [B]. In a pneumatic system there is a limit to the speed at which air can escape the cylinder, preventing abrupt changes in velocity and reducing distance control. Dukane’s servo ultrasonic welder can accelerate up to a rate of 1270 mm/s², allowing almost instantaneous velocity shifts during the weld and hold phases [I]. An initial study of the servo ultrasonic welder in 2009 showed that the servo welder was able to achieve a standard deviation of 1.1% in measured collapse distance compared to 3.9% achieved with the pneumatic welder [C]. Value Plastics was able to achieve a standard deviation of collapse of 0.9% in production using Dukane’s servo-driven ultrasonic welder [I].

Other studies have shown that using servo ultrasonic technology produces parts with more repeatable weld strength. Experimentation at The Ohio State University has shown a standard deviation of weld strength of 5.1% when using Dukane’s servo-driven ultrasonic welder, compared to 9.4% when using a pneumatic welder [D]. At Turku University of Applied Sciences in Finland, experiments demonstrated that standard deviation in weld strength can be halved when switching from a pneumatic welder to a servo-driven welder on parts with shear joints [E].

Clearly, servo-driven ultrasonic technology offers improved repeatability, measurement accuracy and more precision. This improved consistency will be needed as products become increasingly complex.

Weld Strength

In addition to increased repeatability, multiple studies have shown that servo-driven ultrasonic welders produce parts with increased weld strength over parts produced with pneumatic welders [1, 2, 6, 8]. Even under non-ideal circumstances (such as when grease is present in the joint or the energy director is damaged), servo welders were able to create stronger bonds than pneumatic welders [F]. Servo technology has proved to provide greater tolerance of part variations, allowing greater weld strength – as demonstrated by fracture occurring in the bulk material rather than in the joint as was seen when using pneumatics [A].

Experimentation at a Finnish University showed that parts welded with Dukane’s servo-driven ultrasonic welder were 19.1% stronger when using a shear joint and 21.4% stronger when using an energy director than parts welded using a pneumatic welder [E]. In the first study performed by Dukane on the new servo welder, weld strength was 16.7% greater than pneumatically welded samples [C]. Even with just 59% of the energy input, parts welded with Dukane’s servo-driven ultrasonic welder were consistently more leak tight than parts welded with a pneumatic welder [A].

References

A. M. Marcus, K. Holt, A. Mendes. “Benefit of Servo-Ultrasonic Welder to Medical Industry – A Case History” ANTEC 2012.
B.     A. Benatar. “Servo-Driven Ultrasonic welding of Semi-crystalline Thermoplastics” 39th Annual Symposium of the Ultrasonic Industry Association. Cambridge, MA. 2010.
C.     M. Marcus, P. Golko, S. Lester, L. Klinstein. “Comparison of Servo-Driven Ultrasonic Welder to Standard Pneumatic Ultrasonic Welder” ANTEC 2009.
D.     A. Mokhtarzadeh and A. Benatar. “Comparison of Servo and Pneumatic Ultrasonic Welding of HDPE Shear Joints” ANTEC 2011.
E.    H. Turunen. “Ultrasonic Welding for Plastics” Bachelor’s Thesis, Turku University of Applied Sciences, Finland. 2011.
F. T. Kirkland. “Ultrasonic Welding: The Need for Speed Control” Plastics Decorating. July/August, 2012.
G. R. Leaversuch. “How to Use those Fancy Ultrasonic Welding Controls” Plastics Technology. Oct 2002.
H.     M. Knights. “Graphical Analysis Helps Find and Fix Ultrasonic Welding Problems” Plastics Technology. Sept 2005
I. P. Golko. “Boost Performance, Speed, Economy with Servo-Controlled Welding” Plastics Technology. Aug 2011

Dukane Announces ISTeP - An Advanced Test Part

noreply@blogger.com (Dukane Ultrasonics) — Tue, 12 Feb 2013 21:41:00 +0000

Dukane Corporation has taken a significant step to improve the ultrasonic industry’s standard test part. They’re calling it the ISTeP, a two-piece cylindrical part used to test a variety of welded parts’ characteristics. With ISTeP, ultrasonic weld quality and reliability can be determined with enhanced confidence.

ISTeP standard test part

Outside the I-beam – By rethinking the design of the standard part currently used for testing, it became clear there was room for improvement. Consider ISTeP’s cylindrical shape which allows for spin weld testing as well as ultrasonic weld testing.

Dukane’s investment to develop a better industry standard test part included a fresh part design, but also production of a quality injection mold. The ISTeP team took care to create the mold so that gates and knits insured a uniform mold fill, especially in the joint area. There are three joint design options – 60° or 90° energy directors, and a standard shear joint. In addition, the mold has inserts for the joint area. These allow for additional options manufacturers and designers may bring that are unique to their weld joint specifications.

Standard shear joint

Pull Testing – This is simplified by the use of ISTep’s unique tabs, three on the top piece, and three on the lower portion. The tabs help reduce time spent assembling the test part into it’s pull test fixture.

• Bond strength of different plastic resins can be compared - polycarbonate vs. ABS as an example.

• When parts come apart under testing, they will do so evenly, avoiding the so-called “zipper effect” that was previously common.

Energy director joint

Pressure/Burst/Leak Testing - An integral port in ISTeP’s lower portion makes it easy to insert an air tube for a variety of checks that can be made.

Testing Weld Processes and Features– Welding methods each have their distinct advantages. To find which combination of process and features work best, ISTeP could be used with pneumatic and servo welders, using features such as amplitude profiling or Melt-Match^® technology, for instance. Dukane’s enhanced iQ Series generators and software are available to provide even more versatility and possibility to make the testing process complete and comprehensive.

Mold Availability – ISTeP’s injection mold is available from Dukane for firms wanting test parts molded in their resin of choice. Dukane Corporation through its Intelligent Assembly Solutions experts offers experience and know-how for your application.

ISTeP exploded view

Side by side ISTeP standard part

Dukane Donates Equipment to Bioplastics Characterization Lab

noreply@blogger.com (Dukane Ultrasonics) — Tue, 14 Aug 2012 21:59:00 +0000

Dukane Corporation donated a pneumatic ultrasonic welder and loaned a servo-actuator controlled ultrasonic welding system to David Grewell’s bioplastics research group. The new equipment will be used to study various control algorithms for cutting polylactic acid (PLA) films. They were installed in the Bioplastics Characterization Lab, part of the suite of research labs operated by the Center for Crops Utilization Research (CCUR).

Mike Johnston, Dukane Vice President of Sales and Marketing,
shows Sara Underwood, graduate student in agricultural and
biosystems engineering, how to use the ultrasonic welder.

“The donation will enhance learning outcomes in laboratory exercises as well as give students a one of a kind, hands-on experience. In addition, the research with the servo system will allow us to develop fundamental knowledge on ultrasonic cutting,” said Grewell.

Dukane also delivered a 30 kHz handheld ultrasonic welding system to the Department of Agricultural and Biosystems Engineering’s Technology Systems Management teaching laboratories.
Grewell is an associate professor of agricultural and biosystems engineering and CCUR affiliate. His bioplastics research group focuses on formulating, processing, testing, characterizing, and joining bioplastics. He also chairs the Biopolymers and Biocomposites Research Team, a CCUR research program.

Dukane is a global provider of plastic welders for welding thermoplastic materials.

Courtesy of Iowa State University:
http://www.ccur.iastate.edu/news/newsletters/2012/jan_feb/equipmentdonation.html

Why am I getting inconsistent parts?

noreply@blogger.com (Dukane Ultrasonics) — Fri, 03 Aug 2012 20:38:00 +0000

QUESTION: I'm getting inconsistent parts even though I'm following the same parameters. Why?

ANSWER: You need to look at all elements of the project in order to pinpoint the problem. We suggest looking at the molded parts for warpage, heat sinks and cavity-to-cavity variations. Look at the joint design to make sure you have the right joint for the material and the part configuration. For example, using an energy director on a nylon part is a bad match.

Next, check out the elements of the welding system itself. Does the horn match the contours of the part? Or maybe the horn has a small, hairline crack.

Check the fixture to make sure it isn't allowing the part to move around or is in some other way dissipating energy.

Check the booster. Is it providing the right amount of amplitude for the resin and the part design?

The fastest way to diagnose all these problems is with iQ Explorer II advance user software. You can analyze distance, energy level, peak power, force, pressure--any relevant variable-- Along with detailed graphs of the weld process. It's worth the investment.

Call Dukane. They'll come in and do a full diagnostic test using their own iQ Servo welders with patented Melt-Match® technology, and the price is right--it's free!