The Rise of Robots-as-a-Service
Maybe you’ve heard of Software as a Service (SaaS), and maybe even Platform as a Service (PaaS). The intent behind these “as-a-Service” implementations is to democratize the technology while lowering the barrier to entry for businesses, large and small alike. The “as a Service” philosophy is becoming more prevalent in today’s working environment and is spreading to new aspects of work. One of those new arenas is “Robotics-as-a Service” (RaaS). RaaS takes the capabilities of robotics and removes the upfront cost of typically expensive automation upgrades. RaaS is a cloud-based “robotic rental” system that allows users to incorporate the capabilities they need when they need them, upgrade or downgrade systems as requirements change, and install robotics without requiring the necessary infrastructure required by more traditional robotics implementations. RaaS works by utilizing on-site robotic hardware with cloud-based programming and automation, allowing the users to supply power, train the robot, and begin using it. This capability allows users to rapidly spool up production, reduces the upfront installation costs, and adjust capabilities on the fly. Typically, a robot installation requires large amounts of computing power, utilities, and knowledge, and that’s just to get it installed. The cloud-based robotic system removes a lot of the upfront requirements, as the computing power and knowledge are already established at the service provider, leaving just the requirements for the on-site hardware (physical installation and power). Having an established control system and control infrastructure greatly reduces the initial outlay to the user, as they don’t have to purchase those items in addition to the robot. Additionally, as requirements change, the system can be upgraded or downgraded as necessary. This prevents unnecessary robots from taking up much-needed resources like floor space, electrical power, and computing power. Instead of repurposing a now obsolete robot for a job it may or may not be suited for, a new robot that is matched to the job can be brought in and begin producing while the old robot is returned to the service provider. Examples of Robots-as-a-Service include: Building Security: Having robots patrol buildings can result in savings of up to 65% over traditional human guards. Further, the data the robots collect is fed back to artificial intelligence algorithms that can find insights to help make the security systems better. Warehouse Operations: Warehouse operators are often stressed to find sufficient workers during seasonal surges in demand. With a RaaS system, those seasonal labor shortcomings can be mitigated without having to pay for a full-blown system that would otherwise not be needed during other times of the year. Further examples of markets primed for RaaS implementations abound, as the reduction in resources makes these systems more easily available to companies. If you’re trying to figure out how to improve productivity or reduce risk but have always thought robots were out of your price range, RaaS might be the answer for you. RIA
Set for Take Off
The Government recently announced that drones would be used to carry medical supplies from Hampshire to the Isle of Wight, and is funding drone tests and a new air traffic control system. The initiative has been welcomed by the UK industry. Robert Garbett, Founder of Drone Major Group and Chairman of the Drone Delivery Group has welcomed the move by the Department for Transport and has suggested that it will help to open the way to accelerated growth of the UK drone industry. “It will provide the opportunity for UK plc to become a world leader in this fast growth technology,” he said. He has warned that for drones to succeed public perception needs to better understand what is possible with drone technology and how it can be applied most effectively. “In most people’s vision of drone delivery, there is an image of thousands of small air drones with parcels hanging from them being delivered to virtually every home in the Kingdom... but this would be the least practical and least achievable application for air drones yet conceived. Equally, although it may disappoint many people, the opportunity to see all our online orders delivered to our homes by drone any time soon is very slim indeed.” If such a scenario was to be delivered, Garbett makes the point that significant investments in safety, security and expensive infrastructure would be necessary. He does suggest, however, that the future of air drones is far more exciting, and far closer than anyone thinks but that.....”it does not look as the public or the media currently imagine it." According to Garbett the evolution of delivery by air drone is more likely to look like this: Mid-mile delivery – the bulk transportation of cargo from storage hub to storage hub, or from airport to storage hub for onward delivery to increase capacity into remote and hard to reach areas or during emergencies, (such as the delivery of medicines and supplies during the current pandemic) or where access is temporarily restricted. Limited last-mile delivery - the delivery of items between locations where rapid delivery will save or significantly improve quality of life, such as medical supplies, medicines, organs and blood between or to hospitals. Industrial delivery applications – the movement of cargo and assets around industrial and transportation locations such as refineries, airports, or large logistics locations and smaller internal delivery operations for the delivery of mail, spares or tooling. Blue light support – the movement of supplies and equipment in support of blue light operations such as accident and traffic management, crime scene management and terrorist or public safety incident handling. Beyond this he argues that undoubtedly there will be other limited scenarios that will be possible, such as supplies to remote locations, or the delivery of emergency spares and tools to address leaking gas mains or ruptured water mains, as an example. He makes the point that in order for any of this to become a reality all stakeholders in the drone industry will have to recognise the need for drone testing areas for applications to be developed safely and effectively. Which is why the announcement by the UK Government should be welcomed, as we look to facilitate wider-scale adoption of drones. NEWELECTRONICS
Remote Learning: Why Onshape is the CAD Solution
For many students across the country and the world, school is in a state of disruption. At the university level, many students and instructors are moving their teaching and learning entirely online for the duration of the semester. Perhaps you’re in a 3D computer-aided design (CAD) class, working on your capstone, or participating in a competition like Formula Student. Assignments continue and deadlines persist. In order to keep up, you need a CAD system you can access at home since campus computer labs are no longer an option. You need to be able to remotely collaborate with your peers and teammates in real time without worrying about lost data or overwritten work. To top it all off, you need to be able share projects and assignments with your professors and in turn get their feedback. And you need to do it all fast. Enter Onshape. As a professional grade SaaS (Software as a Service) CAD solution, Onshape makes all of this possible: Hardware With Onshape, you can use whatever device works best for YOU. This includes PCs, Macs, Chromebooks, smartphones, or tablets. As long as you can connect to any of these compatible internet browsers, then you should be good to go! No need for a campus computer lab. Tip: View this Onshape help page to read about hardware and graphics performance recommendations. Collaboration You can collaborate with your classmates effectively and efficiently. Whether you’re on a web browser or in the app, you can see and contribute real-time changes and comments using Onshape. The real-time capabilities include chats, task assignments, as well as simultaneous editing on an assembly, part, and even sketches. Tip: Put time management and organization to use when collaborating with Onshape to build soft skills that will stand out to future potential employers. Onboarding Onshape’s fully online system and learning resources make it easy to get up and running quickly, whether you’re a beginner, intermediate, or advanced CAD user. You don’t need to be in a physical classroom to sign up and log on with Onshape—it literally takes just minutes to create an account and start designing. Tip: Onshape has a friendly user interface that is easy to navigate. See how it helped this student team turn their idea into a reality with Onshape. Onshape is a professional, modern CAD system used by thousands of companies. While it certainly solves your immediate problem of having to study remotely, that is just the start. As more and more companies move to a SaaS CAD solution (Onshape being the only one out there), your own move to Onshape during this critical period will prepare you for a successful career with enterprises that are embracing modern CAD and product development. PTC
Need A Free Robot to Clean During COVID-19 ?
During the COVID-19 health crisis, autonomous mobile robots are playing a vital role in helping support essential businesses and their workers on the front lines. Retailers, airports, and hospitals are required to clean more frequently and deliver more cleaning coverage. To help this effort Brain Corporation employees came up with an idea that resulted in the company providing a $1. 6 million program to donate robots to support essential businesses. The Robot Relief program initially came from Brain Corp employees through an internal initiative called “Brain Matters.” Employees were encouraged to think about ways to apply their ingenuity to help the local community with COVID-19. Donating Brain-powered robots and associated services to help those on the front lines is one of the ideas proposed by multiple employees. “ We hope that this donation will make a difference during this pandemic and help businesses to better support and empower their employees while providing a safe and clean environment,” the company said in a statement. BrainOS-powered autonomous floor scrubbers are providing more than 8,000 hours of daily work -- equal to a quarter-million hours over the next 30 days—that otherwise would have to be done by an essential worker. Using these robots allows those workers to focus on other critical tasks, such as disinfecting high-contact surfaces, re-stocking, supporting customers, or even taking a much-needed break. This program includes the rental, deployment, training, and support of the BrainOS-powered cleaning robots at no charge to a business. The robots will be provided for a minimum of 90 days, depending on the changing conditions of the health crisis. This program is available to essential businesses, including grocery stores, medical facilities, manufacturers of essential goods, and organizations that provide professional cleaning services to essential businesses. Users of the cleaning robot under this program can either be in-house cleaners or third-party cleaning service providers. INDUSTRYWEEK
Injection Molding Biopolymers: How to Process Renewable Resins
U.S. injection molders are still pretty green when it comes to processing the new crop of renewably sourced biopolymers. These biologically derived polymers made from PLA, PHA and starch-based resins are attracting growing market interest as materials with no ties to petrochemical-based thermoplastics. These resins require some care in molding so as not to exceed their heat, shear, and hydrolytic stability. Materials suppliers have been developing new and enhanced grades with improved processability and end-use properties, which could help the material to advance into a wider range of applications. Additive suppliers have also come out with products to overcome processing and performance limitations. “We have worked with the majority of the leading suppliers of biopolymers and have trialed the materials extensively,” says Michael McGee, director of technology at Nypro in Clinton, Mass. It’s not as simple as a drop-in substitution for a familiar material like PP. “The rheology, shrink rates, and venting requirements are different from material to material, but the differences are subtle so you have to understand product design, tool design, processing equipment and the parameters of your process. We have been amassing considerable knowledge about biodegradable and biobased materials. We understand more now about their drying, about gate design and location, runner channels, flow rates, venting, and molding.” “Some say they are extremely difficult to process, but that view is starting to change,” says Dr. Jim Lunt, North American v.p. of sales and marketing for Tianan Biologic, a Chinese supplier of PHBV biopolymer (a type of PHA). “Many biopolymers seem tough to process because they have a small window between the melting point or processing temperature and the decomposition point. With biopolymers such as PHBV, a resin may melt at 310 F but degrade at 360 F, which is a fairly tight processing window. Too much heat can generate gels, black specs, or yellowing in your parts.” As a result, molders need to watch their melt temperature, screw speed, and injection speed—as well as proper drying, since these materials tend to be hygroscopic and moisture sensitive. SUCCESSES IN THE FIELD More and more molders are likely to be approaching this learning curve. Biopolymers established themselves first in film and sheet extrusion markets, but successful molded part applications are starting to prime the market for growth. The few current molders of bioresins are targeting mainly rigid packaging, disposable cutlery, medical parts, and consumer products. Nypro says it sees interest in molded parts from biopolymers coming from its core markets in consumer packaging, electronics, telecom, and medical industries. “We are not trying to push the technology, the customers are pulling it,” says McGee. Nypro customers are interested in sustainability and biodegradability and want to know if these materials suit their products and markets. “Demand is growing so quickly, we expect to see double-digit growth for biopolymer products every year for the next few years,” says McGee. Nypro has developed its own proprietary flow-simulation package to simulate molding behavior of biopolymers, including shrinkage and warpage. Consumer products firm Design Ideas introduced its new EcoGen line of bath products produced from the Tianan PHBV materials that are compounded into a proprietary grade by PolyOne. Design Ideas has the products molded under contract in Asia, says Chris Hardy, design director. “EcoGen is our first opportunity to get into injection molded parts that are durable and 100% biodegradable,” he says. As shown on the front cover, the products include a toothbrush holder, bath cup, large and small bath boxes, a pump dispenser, soap dish, and bath bin. Most parts are fairly small, the largest being the bath bin, weighing 500 g (1.1 lb). Meanwhile, EcoGen office desk accessories were launched in 2008. The next development will be larger parts such as storage bins for the kitchen and office, says Hardy. Other injection molding applications for Tianan’s PHBV include dishes, office trays, toys, rulers, pencil sharpeners, cartridges, and plant pots. PHA supplier Telles (a joint venture of Metabolix and Archer Daniels Midland) is focusing on agricultural applications, since its Mirel resin biodegrades in water and soil. An example is an agricultural stake designed to hold down sod. Mirel material is also being used in its first aquatic application. Bioverse Inc. in Pipestone, Minn., is producing a biodegradable version of its AquaSphere Pro pond and lake treatment system for golf courses. Mirel can also be used in single-use consumer items, disposable razors, and packaging. Explained Bob Findlen, v.p. of marketing and sales, “Telles will target rigid applications, where PHA could replace ABS. There is R&D on injection molding parts for hand-held devices such as cell phones and PDAs, and office equipment like printers. There is already a small injection molded pipette tray for laboratory use, which is manufactured by Labcon North America in Petaluma, Calif.” Salvador Ortega, market development manager for NatureWorks, the first and still largest supplier of PLA biopolymer, says a variety of parts are being injection molded, from waste baskets to cups and cosmetic items such as lipstick cases. Ortega says PLA can replace GPPS, HIPS, and ABS: “I think it can compete against styrenic parts and can replace PET and PP in some consumer goods. It shrinks like a styrenic and can use the same type of molds.” NatureWorks also has customers using its Ingeo resin in injection stretch-blow molded bottles for water and dairy drinks. That raises the potential of a market for injection molded PLA preforms, which has motivated some tooling and equipment firms (see below). “Molders are using a number of our injection molding grades,” says Thomas Black, v.p. for the Americas and global alliance manager for Plantic Technologies, an Australian firm that offers starch-based bioresins through DuPont Packaging & Industrial Polymers. “We are transferring our commercial successes in Australia to applications here in North America and in Europe. We are seeing strong interest.” A molder in Australia is producing seedling and planter pots using one of Plantic’s water-resistant grades. Another water-resistant grade is also used to injection mold containers for trapping and killing disease-carrying mosquitoes and their eggs. Now, Plantic is exploring applications in meat packing, such as clips used to isolate animal entrails. Injection molding applications for Cereplast Compostable PLA blends include dental products, toys, tools, tableware, packaging, mugs, and its own Nat-Ur line of disposable cutlery. Cereplast resins are also used in the Natures Plast line of spoons, drink stirrers, sandwich picks, flying discs, and other items from Harco Enterprises Ltd., Peterborough, Ont. Teknor Apex Co., which recently obtained the license for thermoplastic starch (TPS) blends developed by Cerestech, is also targeting injection molding. “We anticipate applications like cutlery, containers, electronics, toys, and other consumer products,” says Edwin Tam, manager of new strategic initiatives. The license allows Teknor to make and sell globally alloys of TPS with PLA, PHA, biopolyesters, and PP. Teknor plans to roll out the first commercial grades at the NPE show in Chicago in June. KNOW THEIR QUIRKS “The biggest issues in injection molding these materials are heat, moisture, and degradation caused by excessive temperature, shear, or residence time,” says Stefano Facco, director of business development for Novamont, a supplier of thermoplastic starch-based resins. Processors face these issues with all resins to some extent, he adds, but a bit more so with biopolymers. “We have found PLA unique in its processing requirements, says Bob Ameel, global business manager for hot-runner systems at D-M-E Co. Compared with standard resins like PS, he says, “PLA retains heat more, so longer cooling time is required. It tends not to flow well in thin walls over long distances. Adding more pressure to fill only increases shear, which can cause it to break down and become brittle.” D-M-E has just commercialized its Eco-Smart standard hot-runner system for PLA and emerging biopolymers. It uses noncorrosive components to resist the acidic properties of PLA and its tendency to plate out acid residues on the walls of the molding system. It also has specially designed nozzle tips to minimize shear and provide high cooling capacity; low-pressure, low-shear channels; and a thermal profile to counteract PLA’s “temperature hypersensitivity.” Bioresins are hygroscopic and must be dried or they will suffer a drop in molecular weight and melt viscosity, as well as increased potential for flashing and brittle parts, says NatureWorks’ Ortega. PLA and PHA are polyesters, and drying requirements are in the range of those for PET and PBT—i.e., more strict than for ABS, nylon, or PC. “Moisture sensitivity and lack of heat resistance appear to be the biggest issues surrounding unmodified biopolymers,” says Marcel Dartée, biomaterials market development leader for PolyOne, which offers a range of bio-based modifiers designed to remedy some processing and performance limitations of biopolymers. Other firms like Arkema, Clariant Masterbatches, DuPont, and Rohm and Haas also offer additive solutions that address these issues (see Learn More box). Dartée says some biomaterials process like a PE or PET. “After some initial adjustments, even an inexperienced molder should be able to process these materials consistently,” he adds. And even if not handled correctly, he says, “Unlike traditional resins, melt degradation of these materials isn’t likely to clog up the molding equipment.” While bioresins have their own particular requirements in terms of drying and processing conditions, Telles applications development engineer Tom Pitzi says that does not always impose any special requirements on tool design. “You can use sub gates, fan gates, all standard gating geometries with Mirel.” Bioresin suppliers say their materials process like traditional thermoplastics such as PC or ABS and can be run on conventional machines using general-purpose screws. They don’t recommend high-shear screws, such as a nylon screw, that can generate a lot of shear heating. Suppliers also warn that you cannot have hot spots in the machine. “A general rule of thumb is for shot volume to be 30% to 80% of barrel volume, much like a standard thermoplastic,” says Plantic’s Black. These materials can be run on any type of injection press. Wittmann Battenfeld says its 5.5-ton Microsystem press is used to mold special PLA resins designed for medical implants. These “bio-sorbable” medical-grade materials reportedly process without degradation in the two-stage dosing and injection system, which minimizes melt residence time. The full inventory of melt is injected on each shot, notes David Purcell, injection molding sales manager. The Microsystem minimizes sprue size, which is significant for these very costly medical grades, which often do not allow use of regrind. It also offers complete integration of feeding, drying, molding, and packaging under cleanroom and dry-air conditions. Stefan Bock, Netstal’s manager of application technology for PET systems in Switzerland, says its PET-Line preform presses have run PLA successfully using its standard PET screw. “The system has to be totally cleaned of PET resin because the processing temperature is lower for the biopolymer. It processes closer to PVC but is less difficult. Molders should hold process temperature to ±2° C,” says Bock. He notes that the hot-runner system may be modified to prevent leakage, and the mold should be run with water at around 24 C (75 F) to avoid plateout. PLA preforms up to 24 g have been molded in PET molds on its presses, says Bock. Netstal isn’t alone in appreciating the potential of PLA preforms. As we reported in February 2008, Husky developed a 24-drop hot-runner system with NatureWorks, bottle maker Biota Brands of America, Inc. (Telluride, Colo.), and stretch-blow machine builder SIG Corpoplast to produce the world’s first compostable water bottle. Husky’s hot-runner system was used with its HyPet injection machine to mold the preforms for 0.5L to 1L bottles. Timothy Womer, chief technical officer at Xaloy, says current-generation biopolymers “process a lot cleaner these days, so a specialized screw may not be required.” Molders might find that these resins process more like engineering thermoplastics than like PE, PP, or PS, he adds. Most biopolymers are semi-crystalline, but they can tend be relatively slow to crystallize or set up in the mold, even though they have relatively low melting temperatures. Additives are helping to overcome this limitation, says NatureWorks’ Ortega: “Nucleation technology is making it possible to improve both cycle times and heat resistance.” Some sources have accused the biopolymers of a tendency to stick to metal surfaces in processing. But suppliers say sticking is mainly a concern when running high levels of amorphous (uncrystallized) reprocessed material. Adding mold release might help reduce chance of sticking to metal surfaces in the press or tool. Today’s biopolymers are designed to process more easily. Many of the materials are “some form of copolymer, with the main aim being to increase the material’s operating window, primarily the temperature gap between crystallization and decomposition,” says Tianan’s Lunt. Use of copolymers also provides the opportunity to enhance or vary properties, such as rigidity or melt strength. “You can now widen the operating window to improve processability. Widening the window allows you to run the product on more conventional equipment.” That doesn’t mean these materials are as forgiving as PE or PS or that they can be run on ancient injection presses where some of the heaters aren’t working, he cautions. If exposed to ambient air, these materials can absorb enough moisture in five minutes to defeat most of the benefits of drying,” warns Jamie Jamison, dryer product manager for the Conair Group. “They need to be properly handled at all stages to minimize moisture regain. If drying temperature is too high, the material may soften and agglomerate in the drying hopper. If it is too low, it will not dry as readily,” says Jamison. Users can employ hopper agitation, fluid-bed crystallizers, or infrared crystallizing and drying units. Typical twin-bed desiccant dryers are not able to maintain the low temperatures required by these biopolymers, owing to temperature spikes after regeneration, warns Sonny Morneault, dryer product manager at Wittmann. His company made software modifications to adapt its Drymax E series dryers, which have special counter airflow and regeneration features, for the lower temperatures needed for bioresins. The updated dryers can maintain drying temperatures of 120 F. Wittmann dried a biopolymer with starting moisture content of 2400 ppm down to 250 ppm in 5 hr at around 158 F, says Morneault. Wittmann also suggests conveying the dried material to the throat of the injection press in small volumes in order to minimize chances of moisture regain. Says Novamont’s Facco, “Starch-based materials must be purged out from the barrel by LDPE at the end of production to prevent excessive degradation.” Telles’ Pitzi also recommends purging Mirel PHA, and most sources do not recommend leaving bioresins in the machine at the end of the work day. Autodesk’s Moldflow laboratory has been investigating the processing of biopolymers to optimize its simulation software for these materials, according to Russell Speight, senior manager and principle materials engineer at the lab in Melbourne, Australia. SUPPLIERS’ GUIDELINES At least eight companies offer or plan to offer injection moldable biopolymers. NatureWorks’ Ingeo PLA line includes three injection grades, though its newest—Ingeo 3251D—is a higher flow material that will replace the previous two Ingeo grades (3001D and 3051D). NatureWorks developed Ingeo 3251D for thin-wall applications. It has a melt flow of 70 to 85 g/cc at 410 F and 30 to 40 g/10 min at 374 F. Those compare with 10-25 g/cc and 10-30 g/cc, respectively, for the older injection grades. Mechanical properties are said to be virtually identical to the other grades. It can be molded with the same screws and molds used for PS, SAN, and ABS, though gating changes are required. Ingeo 3251D is transparent and is aimed at consumer electronics, cosmetics packaging, housewares, toys, and custom molding. “We are initially targeting semi-durable parts (less than 3-yr life) where process heat requirements are no more than 370 to 410 F,” says NatureWorks’ Ortega. “We get good optics, high clarity, high gloss, high modulus, good toughness, and UV transparency with no UV stabilizer required. The material should be dried to less than 400 ppm moisture, with best moisture content being less than 100 ppm. It can be dried with desiccant, infrared, and wheel-type dryers at 80 C for 1-2 hr, or 3-4 hr if the bag was left open.” NatureWorks recommends a general-purpose screw with a 3:1 compression ratio and 20:1 L/D to melt the material without excessive shear. Feed-throat temperature should be about 70 F, while recommended melt temperatures are 370 to 410 F. Screw speeds from 100 to 200 rpm should be used with 50 to 100 psi backpressure. Metering zone and nozzle should be at 370 to 400 F. Molds should be kept cool, around 75 F, and expect part shrinkage 0.004 in./in. Novamont’s Mater-Bi starch-based biopolymer comes in an injection grade with MFI range from 6 to 30 g/10 min. It should be processed with a constant-taper, single-flighted screw having a 2.5:1 compression ratio and 25:1 L/D. A standard check ring can be used, along with medium to high injection speed, says Facco. Melt temperature is 302 to 430 F. Molding of semi-crystalline biopolymers can be up to 50% slower than more commonly used semi-crystalline resins. Mold temperature of 65 F is typical. Novamont’s Facco says any gate design can be used with Mater-Bi. Minimum gate size is normally 1 mm (full round) but can be greater or lower depending on the particular grade’s viscosity. Cold or hot runners are both suitable, notes Facco, though “the manifold must be free of dead spots and the nozzles of a free-flow type.” The company also recommends fast injection. Mater-Bi may require use of stainless-steel tooling. Molds are typically run at 68 to 104 F Novamont can perform Moldflow simulation of mold filling. The company can develop process guidelines and can specify part wall thickness, pressure, sprue diameter, and use of hot or cold runner. A biopolymer made from chemically modified, high-amylose industrial cornstarch by Plantic Technologies of Australia is offered here in five injection grades by DuPont under the Biomax TPS (thermoplastic starch) brand. There are general-purpose, high-flow, and water-resistant grades, as well as an “engineering” grade for thick parts requiring high stiffness. Two water-resistant grades withstand water exposure for up to four or 12 weeks before biodegrading. Low-compression screws (2.2 to 2.8) with a 20:1 L/D are recommended. “A screw you might use for flexible or rigid PVC will be fine,” says Plantic’s Black. Mirel PHA (polyhydroxyalkanoate) resins from Telles are described as high-performance semi-crystalline polyesters engineered for high modulus. They are made by bacterial fermentation of cornstarch. The new P1003 injection molding grade will replace two other experimental grades (P1001, P1002). “It is a huge market opportunity for us. There is strong demand for it to be readily injection moldable in durable applications,” says Telles’ Pitzi. Mirel should be dried to 1000 ppm (0.1%) or less. P1003 is processed using a reverse barrel-temperature profile ranging from 350 F in the rear to 320 F at the nozzle. “We are cooling down the melt as we go through the process,” says Pitzi. He recommends use of a single-flighted, general-purpose screw with 2:1 to 2.5:1 compression ratio. Backpressure can be as low as 50 psi. Screw speed should be 50 to 150 rpm. Mirel has a recommended melt temperature of 320 F, and it decomposes above 356 F so control of melt temperature is vital. Molders should inject slowly at first—0.5 to 2 in./sec—then gradually increase the speed until 95 to 99% of the mold is filled. Injection pressures from 5000 to 13,000 psi have been found to work, says Pitzi. To avoid longer residence times, keep no more than three to four shots of material in the barrel, though two is better. Mold temperatures should be 120 to 140 F to promote crystallization. “Instead of injecting into a cold tool at 70 F, we run the mold at 140 F. If you run it too far from the melt temperature you will waste time trying to get the heat out. Allow the material to crystallize first, then you cool it,” says Pitzi. Telles recommends that gate sizes be up to 80% of the part thickness. Most parts require 3 to 5 tons/sq in. of clamp force. Pitzi says Telles has been working with the Autodesk Moldflow simulation software to develop a database. Mirel can be used with hot runners and valve gates. It can be purged with LDPE. Tianan Biologic’s PHBV (polyhydroxybutyrate-valerate) is a bio-polyester produced via bacterial fermentation of plant starches. The Chinese company is said to be the world’s largest producer of PHBV, a member of the PHA family. Its Enmat PHBV material is approved for food contact in Europe and is approved by the Biodegradable Products Institute (BPI), N.Y.C., for composting. Tianan offers Enmat Y1000P injection grade powder and pellets and EnMat Y5010P pelletized blend of PHBV and BASF’s Ecoflex biodegradable (but not bio-based) resin. Compounder PolyOne formulates an injection grade based on the Tianan material blended with its biodegradeable additives. PHBV should be dried to 250 ppm moisture. Tianan recommends a melt temperature of 338 to 347 F. Users should keep feed throat temperature to no more than 275 F, compression section to 293 F, metering section to 311 F and adapter temperature to 322 F. Tianan says shrinkage of its PHVB is similar to that of PLA. Cereplast supplies a Compostables line composed of PLA blends and a new “Hybrid” line of starch reactively blended with PP. Cereplast offers standard and higher flow (35 MFR) Compostable injection grades, as well as one recommended for cutlery, plates, and bowls and one with higher flexibility for freezer applications. Processing recommendations for new Compostable 1001 grade are shown in the accompanying table. Teknor Apex says its TPS/PP blends can run in standard injection machines with no screw modification. Cereplast recommends low-shear screws with its starch/PP Hybrids. Cereplast recommends melt temperatures below 392 F. Teknor says its new blends can take barrel temperatures up to 400 F. Tam recommends slow early-stage injection, larger-diameter nozzles, and vented molds with cold slug wells and full-round rather than half-round runners. PLASTIC TECHNOLOGY
How to Choose the Optimal Temperature Sensor
When designing a temperature detection circuit, it is important that you don’t pay for more than what is actually needed. By understanding the requirements of an application, an optimal temperature sensor can be selected that minimizes cost without compromising performance, accuracy, or reliability. There are several factors to consider when selecting a sensor. Temperature Sensor Selections Temperature Range The first consideration when selecting a temperature sensor is temperature range. For operating environments over 1000 °C, for example, a thermocouple is often the only option. However, only a few applications involve such extreme temperatures. For most industrial, medical, automotive, consumer, and general embedded systems, the typical operating temperature range is much narrower. When semiconductor-based components are in use, the range is even more limited. For example, MCUs for commercial and consumer applications are rated at 0°C to 85 °C. MCUs for industrial applications extend the range to -40 °C to 100 °C while automotive MCUs need to operate from -40 °C to 125 °C. Thus, engineers often have the option of using any of the standard types of temperature sensors. Packaging A temperature detection component needs different packaging, depending upon what is being measured. For example, a semiconductor-based sensor cannot be immersed directly in hot oil. A low-cost sensor may be protected by an epoxy coating. For higher temperature operation, the temperature sensors can be hermetically sealed in glass. This also protects them from other environmental factors, including liquids and debris. Sensors can be placed in stainless steel housing for greater robustness. The more complex the housing required, the greater the cost for the sensor. Sensors also come in a variety of shapes and sizes. Selecting the appropriate sensor for an application can improve performance, responsiveness, and reliability. For example, all temperature sensors are subject to self-heating due to the power running through them. This self-heating raises the ambient temperature around the sensor, thus introducing error and negatively impacting accuracy. With an NTC thermistor, the mass of the sensor can be increased to reduce the errors due to self-heating. Even a small change in size can have a large impact on reducing self-heating. For example, a 3 x 3 x 3 mm thermistor has more than 3X the volume/mass compared to a 2 x 2 x 2 mm thermistor. This flexibility is only possible with a thermistor. Semiconductor-based sensors by their nature are fixed in size. As both RTDs and thermocouples are wire-based, this limits an engineer’s ability to adjust their mass to reduce self-heating errors. Stability A temperature sensor can drift over time, depending upon the materials, construction, and packaging used. For example, an epoxy-coated NTC thermistor changes by 0.2 °C/year while a hermetically sealed one changes by only 0.02 °C/year. Platinum RTDs offer excellent stability as well: 0.05 °C/year for film and 0.002 °C/year for full wire. Both thermocouple and semiconductor-based sensors have much lower stability at 1 °C and 2 °C/year respectively. Stability is important in applications that need to be operational for many years. The effects of stability can be mitigated if the system can be calibrated from time to time, though this comes with the trade-off of introducing maintenance complexity and cost. Ideally, the stability of the system is enough to extend through entire expected operating life. Accuracy Without a reliable detection circuit, the quality and reliability of temperature control and compensation functionality degrades. There are several factors that affect the accuracy of a temperature detection circuit, including resolution and responsiveness. Accuracy is clearly a concern for applications where precise temperature control is required. However, accuracy can also have a substantial in applications where temperature is solely a reliability concern. Consider an embedded system that employs a fan to keep the MCU from overheating and as a result losing reliability. The fan turns on whenever an upper threshold is exceeded. If a low-cost thermocouple is used, the accuracy of the measurement could be off by up to 5 °C. In addition, the responsiveness of such a thermocouple is on the order of 20 s. This means that when the upper threshold is exceeded, the temperature might have been rising steadily for another 20 s before the system can register the change. It might also take additional time for preventative measures to take effort. Furthermore, with a stability of 1 °C/year, a device expected to operate for 10 years will need to account for another potential 10 °C variation. When selecting the upper threshold temperature, engineers have to take into account that this thermocouple-based detector circuit could be 5 °C and 20 s behind where the system truly is. One solution to the accuracy issue is to calibrate the detection circuit during manufacturing. However, this adds undesirable expense. More commonly, engineers will lower the upper threshold to a level where, to compensate for the 5 °C variation and 20 s delay, the system will have less chance of overheating beyond its reliability limits. A lower threshold, however, means that preventative measures will be enacted sooner than they would need to be with a more accurate and responsive detection circuit. It’s like running the A/C when you don’t have to. Such overuse impacts the reliability of the fan and consumes more power than necessary. An NTC thermistor is able to achieve the highest accuracy of the basic sensor types within the -50 °C to 250 °C range. Accuracy ranges from 0.05 to 1.5 with high long-term stability, depending upon the type of sensor and packaging used. NTC thermistors also offer superior responsiveness, on the order 0.12 to 10 s. Contrast this to the very slow responsiveness of a platinum RTD or semiconductor-based detector at 1 to 50 s and 5 to 60+ s respectively. By the time other components have registered a change in temperature, an NTC thermistor-based circuit has already enabled the system to take corrective action. The result is that with an NTC thermistor, engineers have the ability to select a tighter upper threshold, optimizing both fan reliability and power consumption. In addition, because of its fast responsiveness and the wide dynamic range of its output resistance, NTC thermistors can be very accurate over even a small range of temperature. This makes them extremely versatile across a wide range of embedded applications. Noise Immunity There are other factors that affect accuracy, including susceptibility to electrical noise and lead resistance (i.e. noise arising from the leads coming out of the temperature sensor component). While thermocouples are not affected by lead resistance, they are the most susceptible to electrical noise, especially cold junction thermocouples. Semiconductor-based sensors also experience no lead resistance but immunity to electrical noise depends upon the board layout. Platinum RTDs are fairly immune to electrical noise but they are quite susceptible to lead resistance noise, especially in 3- and 4-wire configurations. NTC thermistors, because their initial resistance is so high, have excellent noise immunity to both electrical noise and lead resistance. Cost The cost for a temperature detection circuit typically rises with increased accuracy for a particular sensor type. More robust packages will also increase cost. For applications in the temperature range of -50 °C to 250 °C, platinum RTDs have the highest cost of up to $6. Semiconductor-based sensors are the next highest, at around $0.9. Thermocouples have a reputation for being low cost, but are actually moderate in cost at $0.5. NTC thermistors come in at the lowest cost at <$0.2 for a hermetically sealed, glass encapsulated sensor. If the application does not require a hermetically sealed sensor, NTC thermistors can be less than $0.5 each in volume. AMETHERM
Ferrous vs. Non-Ferrous Metals: What's the Difference?
The short answer is iron! Ferrous metals contain iron, while non-ferrous metals do not contain iron. However, the difference in the composition of these types of metals means that each has unique qualities and uses. So let's learn more about the differences between ferrous and non-ferrous metals. Ferrous Metals As we mentioned earlier, ferrous metals are types of metals that contain iron. Since ferrous metals are known for their strength and durability, they are often used in both architectural and industrial fabrication. Due to the iron they contain, ferrous metals are also magnetic. Some examples of ferrous metals include: 1. Steel Steel is made by adding iron to carbon, which strengthens the iron. This type of metal is frequently used in construction and manufacturing industries. 2. Alloy steel Alloy steel is created by incorporating elements such as chromium, nickel or titanium to enhance the metal's durability and strength without increasing its weight. This type of metal is often used in manufacturing related to construction, machine tools, and electrical components. 3. Carbon steel This metal's higher carbon content makes it one of the hardest steels available. Carbon steel is often used when manufacturing machine tools such as drills and blades. 4. Stainless steel One of the most durable types of steel due to its ability to self-heal. Stainless steel is also heat and corrosion-resistant. Due to its durability and resistance to corrosion, stainless steel is used to manufacture a variety of tools and appliances such as surgical instruments, storage tanks, grills, refrigerators, and pipes. 5. Cast iron Cast iron manages to be strong and very brittle at the same time. This kind of metal is often used when manufacturing engine blocks and manhole covers 6. Wrought iron An alloy with very little carbon content, wrought iron is resistant to corrosion and oxidation due to the addition of slag during manufacturing. This type of metal is often used for manufacturing chains, barbed wires, and railings. Non-Ferrous Metals Although non-ferrous metals are typically not as strong as ferrous metals, their lack of iron does give them some advantages. Non-ferrous metals are far more malleable and have a higher resistance to rust and corrosion. Some examples of non-ferrous metals include: 1. Aluminum This metal has low strength but is very light and highly malleable. Its lightweight makes it ideal for the manufacturing of aircraft or food cans. 2. Copper Copper is malleable and has high conductivity for electricity and heat. Due to its incredible conductivity, this type of metal is often used when manufacturing wires or other conductors. 10. Zinc Zinc is stronger than most non-ferrous metals and has a very low melting point. This type of metal is often used in galvanization (the process of applying a protective coating to iron or steel to prevent it from rusting) 3. Brass Brass is a combination of copper and zinc. This type of metal is often used when manufacturing ornaments and electrical fittings. 4. Lead This heavy malleable metal has a low melting point and low tensile strength. Since it is highly resistant to corrosion, lead is often used in electrical power cables, batteries, and building construction. 5. Tin An extremely soft and malleable metal, tin is often used to coat steel to prevent corrosion. This type of metal is widely used for plating steel cans that contain food and in metals used for bearings. CAMM METALS
A Brief Overview: Cost Saving Welding Tips for Your Next Welding Project
Are metal welding costs draining your fabrication project’s budget? It’s possible that your fabrication partner isn’t doing everything possible to optimize their welding processes and find ways to minimize your expenses. It’s a difficult balancing act. After all, the end product’s structure and safety is dependent on the strength of the welds. Any welding defects will result in additional costs for your business. Check in with your metal fabrication partner to find out if they offer any of the following welding solutions to drive down your project costs (without sacrificing quality). Eliminating Unnecessary Welds from the Design It’s important to work with a welding contractor who you can trust to look for ways to modify product designs to eliminate unnecessary welds. For instance, if one company that manufactures boxes originally has a design that calls for welded lift handles on each side of the box, the welding partner could save money by simply changing the design of the box to cut out lifting slots, eliminating the need for welding the handles. Essentially, there are many instances where a professional welder will be able to recognize the opportunity to eliminate unnecessary welds from the design, saving time and money down the road. Optimize Welding With Other Fabrication Processes It’s not surprising— OEMS typically use welding contractors for more than welding services alone. Typically, it’s fair to expect your metal manufacturer to supply material and fabrications as well. It’s common for OEMs to request specialty welding, machining and painting services grouped together as one project. Ideally, suppliers must use their specialized knowledge to streamline welding with other manufacturing services. For instance, we work on many projects where a part may need post-weld machining using a large piece of equipment. In cases like that, it’s important that the project is optimized to save time. If the feature that needs to be machined is small, your supplier may opt to machine the component on a smaller, less expensive machine before welding. However, it must be pre-machined in a way that compensates for how welding will change and distort the part. You save money by using less expensive machining equipment if your welding contractor’s plan is successful. Understand the Nuances and Science of Welding Welding is a balance of art and science. As you may know, the order in which your fabrication partner applies welds affects the quality of your completed parts. Heating a metal causes it to move, shrink and distort. If your supplier controls the distortion, it controls how your finished part comes out. Believe it or not, suppliers can actually assemble components improperly, knowing that the welding process will inevitably change certain features, and end up with a correct assembly. In other words, if a professional welder understands that something is going to move an inch after welding, he or she can compensate by moving it an inch the opposite way prior to welding. Essentially, if you work with a professional welding supplier with years of expertise, you are more likely to receive higher-quality parts and fewer welding defects that would otherwise slow down your production line. Minimize Welding Equipment Downtime Wasted time costs money for both you and your fabrication partner. The two most effective methods for a welding contractor to reduce welding equipment downtime is to use the appropriate filler metal packages and to schedule downtime for machine maintenance. Ideally, your welding supplier should use filler metal packages that are large enough to reduce wire changeovers. Yet, the packages should not have so much excess wire that they can’t be used within a few days. Once the package is opened, the filler metal absorbs moisture from the environment and contaminants like dust and oil, which will negatively impact welding processes. Your partner’s adherence to scheduled machine downtime will help to prevent equipment failure, ensuring higher-quality parts with better equipment performance. Your welding partner will be able to offer more efficient welding services at a better cost by reducing machine downtime. Your welding contractor should make your budget goals its focal point. The right partner for your business continuously improves its processes, supporting your growth by working with you to minimize costs as your needs change. CAMM METALS
Back to Basics - Learning About Variable Speed Drive VFD
A variable-speed drive (VSD) is a piece of motion control hardware that regulates the RPM (Hz) and/or torque (voltage) of an AC motor.Some people simply call them "drives" but they go by a number of different names including AC drives, inverter drives, frequency inverters, adjustable-frequency drives (AFD), variable-frequency drives (VFD), variable-voltage drives (VVD) and micro drives.You might find a VSD in a water treatment facility, where water pumps are used to control the amount of water coming into, and leaving, the plant.A VSD might be controlled manually via it's hardware interface or intelligently via a programmable logic controller (PLC).Without a VSD, and when a motor's RPM or torque is too high or too low for its application, mechanical controls are sometimes used to slow, shift and control an application's output — this is often wasteful, using energy and materials inefficiently.Variable-speed drives are a great alternative to mechanical equipment because they can regulate process output right at the source, saving energy and money whilst cutting down on motor wear, maintenance and scrap.Implementing VSDs around your facility can be an excellent way to meet your annual emissions and environmental goals, financial goals or just reduce the noise around the facility.Finally, although a VSD should not be confused with a soft starter, you can also use a VSD to "soft start" motors with a heavy load when they are being powered up and powered down. Again, this provides significant cost and wear benefits for the motor, preventing overheating and excessive wear.If you want to know more about variable-speed drives or if you are simply looking to purchase, please contact one of our team members at Fictron.We support, sell and repair industrial drive equipment for a number of key brands, including KEB, Lenze, Yaskawa, Mitsubishi, Danfoss, ABB, Siemens and Allen-Bradley.
What's the Difference Between Carbon Steel and Stainless Steel?
When you're embarking on your next metal fabrication project, it's important to consider which type of steel you will use. Selecting the appropriate type of steel for a metal fabrication project is a critical and less-mentioned decision. Before you even begin to contemplate between which individual grade of steel you'll choose, you first have to determine what type of steel to use. Typically, the choice is between carbon steel or stainless steel. Appearance If the particular job requires an aesthetic appeal, it’s important to consider the appearance of the metal. Frequently, stainless steels with particular finishes are preferred when cosmetic appearance is important to the customer. Even to a casual observer, carbon steel and stainless steel have a few distinguishing characteristics. Typically, carbon steel appears dull with a matte finish. On the other hand, stainless steel appears to be more glossy and comes in various grades that can increase the chromium in the alloy until the steel finish is as reflective as a mirror. Though both can be sanded and polished to have a bright, shiny appearance, carbon steel requires a clear coat of paint rather quickly after the polishing process to avoid tarnishing and eventual rust. Cost Implications As with any project, cost is an important consideration. Although different grades have varying costs, it's fair to say that stainless steels are often more expensive than carbon steels. This is largely due in part to the fact that stainless steels have additional alloying elements, including chromium and nickel. These additional elements all add up to an increased cost when compared with carbon steels. Carbon steel, by comparison is mostly composed of relatively affordable iron and carbon elements. So, if you're next fabrication project requires a tight budget, carbon steel is likely the better option. Properties Again, it's not fair to make sweeping statements about the differences in mechanical properties between carbon and stainless steels, since there are a variety of different types and grades of each. Stainless steels can be more ductile than carbon steels because they usually have higher amounts of nickel. However, there are very brittle grades of stainless steel as well, such as the martensitic grades. Carbon steels with very low amounts of carbon may not match tensile strengths of some stainless steels due to the alloying elements that many stainless steel grades contain, which increase its strength. Corrosion Resistance One of the most often discussed differences between carbon steels and stainless steels is their ability to resist corrosion. Stainless steel often offers more corrosion resistance. Both carbon steels and stainless steels contain iron. Iron oxidizes when it's exposed to the environment, creating rust. However, stainless steel has added chromium, which helps to make it more corrosion resistant than carbon steels. Here's how it works: the chromium attaches itself to oxygen more easily than iron, creating a chromium oxide layer, which protects the rest of the material from degradation and corrosion. So, if corrosion resistance is important for your project, stainless steel is the way to go. CAMM METALS BLOG
How Laser Cutting Can Improve Your Next Fabrication Project
The modern metal fabrication process is composed of a variety of techniques that promise quality returns; laser cutting stands out as one of the most interesting, as it’s adaptable, precise, and efficient, which make it quite compelling whether you are seeking help on a simple or complex fabrication project. Consider Material Thickness and Type During the Design Process When you begin the design process for your next project, consider your options in regards to the type of material and required thickness. As you know, different materials burn at different rates, and the thinner the material is, the faster the laser will cut through it. After all, you are paying for the time the laser spends running. Ultimately, choosing the proper material type or working to find the optimal material thickness for your part can help to cut laser cutting costs considerably. This isn’t always easy, though, depending on the complexity of your project, so if you have questions about material type or thickness in consideration for an upcoming project, feel free to contact us. Simplicity is Your Friend Keeping design elements simple is an often overlooked aspect of project planning, yet it’s valuable to strive for designs that will minimize laser-cutting time. It’s not always easy to design a project in its simplest form, but remember: the less time it takes to cut, the less it will cost. You end up paying for every movement a laser cutting makes. Whether a technician is cutting, engraving or traveling between cuts, it adds up. To help your design details stay simple, remember that tracing small detailed shapes with the laser cutting machine will eat up more time than tracing larger ones and straight lines take up less time to cut than circles. Remember, Laser Cutting Is Just One Piece of Metal Fabrication While it’s beneficial to find a metal fabrication company that can build the main part of an enclosure or a custom part, it’s much better when you find a company that can also perform the powder coating, spot welding, and other techniques that transform your planned component into a seamless finished project. Some may argue, why can’t I contract out different parts of the job to as many low bidders as necessary? The answer is simple: no matter how cheap these services are, the added logistics of working with multiple companies immensely burden the project, often leading to increased overhead and potential costly mistakes. Laser cutting and fabricating technologies have been around for a long time, so it’s preferable to find a qualified vendor that can offer a wide variety of complementary services. It's Critical to Find the Appropriate Fabrication & Laser Cutting Partner As you can imagine, success in any fabrication project is entirely dependent on absolute accuracy; finding a company with skilled workers who can perform precision laser cutting for your parts and comments is crucial to ensure high quality products. Does the company have on-site testing capabilities? Detailed inspections are necessary to guarantee the accuracy of laser cutting processes and fabrication procedures. Look for a company that can conduct these tests on-site and offer quick feedback on the precision achieved for your components— this is helpful for evaluating the quality of their services. Is the company accessible and easy to work with? Does the prospective fabrication and laser cutting partner offer the ability for you to scan and transmit drawings electronically? This can help to greatly speed up the production process while improving overall productivity. Keep in mind: companies that can receive a wide variety of electronic formats are quite helpful in providing added flexibility and improved speed for last minute changes and adjustments to necessary parts and components for your company. Has the company proven to be a reliable presence in the industry? Search for a company with a stellar track record of quality and on-time delivery. Ultimately, hiring an experienced laser cutting firm with a reputation for dependability can help you to manage supply chains more effectively. Scour through company reviews and look through a gallery of their recent projects— if the company is proud of their work, they should be showing it off! CAMM METALS BLOG
How Swarm Bots will Change the Construction Industry
In the construction industry, safety is paramount. Some environments during construction phases are obviously unsafe and don't have viable human solutions -- ask a worker to reinforce a levee wall while it’s failing, and you will get “no” as a response. But, what if you could build that wall without risking life and limb? That’s where swarm-bots come in. Swarm-bots are a technological marvel that takes the benefits of robots and combines them with the power of large numbers. The idea is to utilize very simple robots in large numbers to build a design without central guidance. These robots have limited physical abilities and limited programming, and yet can build amazing things. By working in this way, a large number of low-cost, simple machines can rapidly create structures in places where higher capability machines would be cost-prohibitive and the risk to humans would be too great. One such example of swarm-bots takes their inspiration from the lowly termite. Despite its diminutive size, the termite is one of nature’s most ingenious builders and, in large numbers, is capable of creating amazingly complex mud structures. How the termites do this is interesting as they do not follow the commands of a central “architect” termite, but rather the rules of behavior are imprinted in its DNA.Using the termite as their example, the team at Harvard's Self-organizing Systems Research Group built a group of swarm-bots that are capable of building a brick wall. Give the swarm-bots the final design, set their rules for operating, and set them to the task. The swarm-bots will go about building the wall, working as a team while maneuvering around the other swarm-bots. Each robot in the swarm will grab a brick, or work collectively to do so, and place them in open slots until the wall is finished. If one malfunctions, the others continue the work and all you lose is the productivity of the one robot. With no central control, a single point of failure does not exist, improving reliability and redundancy. Just like the termite, the swarm-bots can rapidly, safely, and effectively create structures in almost any location. The best part of this is construction workers won’t lose their jobs, which seems to be the biggest fear of automation. Swarm-bots will perform the jobs that are too high-risk for human workers, the jobs that aren’t getting done now. Want to colonize Mars? Send swarm-bots and supplies to create the infrastructure to allow for safer human habitation. Have a levee failing because of flooding? Send in swarm-bots and supplies and keep the human workers safely away from the area and working on other issues. With swarm-bots, you gain capabilities to increase construction activity as they perform the dangerous jobs, reducing risk to the point where humans can begin working. Extremely simple, low cost, and effective, swarm-bots can turn areas that are too dangerous for human workers into opportunities for immense growth. Construction technology advances such as this will be the catalyst for future advancements such as cities beneath the sea or colonies on other planets. Swarm-bots won’t take over the construction industry, they will help expand the industry’s capabilities. RIA