Discover what’s on our minds and let us know what’s on yours. Check back often to learn about new thoughts, events, information, or ideas we have regarding the possibilities of plastic extrusion!
Fun Fact Friday – Pasta!
I’m not sure I know anyone who doesn’t love pasta. Even the pickiest of toddlers enjoy the delicious, hearty, carb-filled food. October 17, 2017 was national pasta day. Mark your calendars next year to celebrate if you didn’t this past Tuesday! And as if having pasta in our lives wasn’t great enough, it comes in all sorts of shapes and sizes for our enjoyment. To make that possible, we rely on extrusion.
Each pasta–just like each plastic profile–comes from its uniquely shaped die.
Extrusion is part of our everyday lives–even our dinner plates! For pasta extrusions, reach out to your local grocery store. For your plastic extrusion needs, reach out to Formtech.
Custom Plastic Extrusion Terms – Part Two
We hope you found part one of our four-part series on extrusion terms insightful. In the first of the series we discussed extrusion industry terms you may hear related to extruders and tooling for the extrusion industry.
In part two of our series, we are going to tackle the top 10 thermoplastic extrusion terms relating to ancillary or downstream equipment used to manufacture custom plastic profiles, tubing, and other hollow profiles.
Gravimetric Feeder– In part one of our series, we discussed that the hopper holds material that is fed into an extruder. These can be as simplistic as a steel “funnel” configuration that does little more than hold and feed material to very precise feeding systems that rely on gravimetric measurement to deliver accurate amounts of plastic material to the barrel and screw of the extruder. In tight tolerance situations, you will find many extrusion lines outfitted with this type of equipment. In the case of a custom color matched, single durometer extruded profile, you would have a natural color base compound and a color concentrate. This can be done with a gravimetric feeding system that feeds two materials to the extruder at the same time. When appropriate, a three-station unit can be used to feed in precise amounts of reprocessed plastic to manufacture the finished extruded profile in the most environmentally friendly way.
Vacuum Calibration– In our first part of the series, we compared plastic extrusion to pasta making. Both processes use “ingredients” that are fed into an extruder, conveyed down the barrel with a screw, and are forced out a die to make a specific shape. In the case of pasta, there is very little heat created during this process. However, to make plastic into a product using the extrusion process, both frictional and external heat are used. The heat forces the material through the extrusion die, then the manufacturer must captures the profile to maintain the overall shape and integrity of the profile during the cooling process. Water, other liquid coolants, or air can be used in the cooling process. Tolerance requirements may dictate that vacuum calibration (also called vacuum sizers) be built and used to capture the profile, using vacuum to hold the extruded profile in place during the cooling process. Most vacuum sizers today use water for heat removal.
Cooling Systems– Methods of cooling are dependent on the profile design. In some cases, a simple water-pan can be used to hold water or other coolant. This type of equipment is widely used in the extrusion of flexible profiles such as screen splines, extruded gaskets, and other smaller profiles. Another option is systems designed to hold guides and coolant. However, To manufacture more complex products (window lineal profiles, office partition base raceways, entry door seals, wood plastic composite components, wall protection corner guards & crash-rails, and other custom profile extrusions,) the extrusion manufacturer may use a calibration table. As the name implies, this is a very rigid stand that is designed to allow both vacuum sizing and water cooling tanks to be mounted for cooling and sizing purposes. The calibration stands vary in length to accommodate a wide variety of extruded plastic profiles. Typically, this type of stand has self-contained vacuum pumps along with both water and air supply with quick-change couplings to reduce set-up time during tooling changeovers.
Embossing or Texturing– Many extruded profiles you see have textured or embossed patterns on the exposed surface. The next time you are in a commercial building look at the extruded handrails and corner guards protecting the walls and corners in the building. Most of these products will have a pebble grain embossed pattern on the surface to add to the aesthetic appeal of the product, while offering the protection and durability high impact, rigid plastic materials provide. Another great example of textured, or embossed products are the baseboards or wire raceway covers on open office partitions. These panels are subject to abuse from foot traffic as well as cleaning equipment, and the textured pattern helps minimize cuff marks and scratches. Formtech has embossing equipment at both manufacturing locations. Patterns can vary from a typical pebble grain, to custom designs, or to wood grain textures resembling real wood.
Tape Applicator– Many plastic extrusions have double sided adhesive tapes, or even magnetic strips, applied to them for additional functionality. Some examples of this added functionality on extruded plastic profiles would include point of purchase display tags, Velcro®, automobile body side moldings, wall protection corner guards, and weather stripping. Anytime you here the term peel and stick, this is the added functionality the addition of pressure sensitive adhesive tapes can provide to your extrusion. Need to attach a vinyl extrusion to a piece of steel? Formtech can custom apply magnetic tape to the extrusion that will attach to a metal surface. You don’t need to attach to steel? Double sided foam and non-foam adhesive tapes specially formulated to adhere to a wide variety of surfaces can be applied to the plastic extrusion on an in-line process to maximize function and minimize cost. Formtech has considerable experience with tape application, and we have specially designed tape applicators that can be used for many custom extruded shapes.
Haul-Off– In extrusion jargon, you will hear many terms used to describe a puller, conveyor, or haul-off, which is used to pull and convey extruded profiles down the extrusion line before being cut to lengths you can see from the picture below, top and bottom cleats, or belts, are used to apply pressure on the extruded profile as it is being pulled downstream. The belts can be made from a variety of materials, including foam, silicone or even rubber. Careful adjustment is required to maintain the plastic extruded profile integrity, without distorting the shape as the product passes through the unit. In many cases an additional speed controller is located near the extruder so the line operator can speed up or slow down the haul-off when controlling the size of the extruded profile.
Cut Off Saws– Plastic extruded profiles are linear products, and must be cut to length before they are removed from the extrusion line and packaged. A traveling saw is used primarily with medium to large profiles. The traveling saw, or progressive saw, clamps onto the profile to move the cut-off saw downstream with the product until the saw can cut through the extrusion. Many traveling saws have the blade mounted above the profile, and cut down through the part much like a miter saw used by homeowners and contractors. Notice the progressive saw in the picture has the blade contained in the bottom of the unit, and it travels up through the plastic part. This can help control dust and saw chips more effectively when this type of saw can be used.
Fabrication Punch– The traveling saw has limitations, and is used only when extruded profiles are square cut at a 90° angle, or some consistent angle to make a trapezoid shape. This simplistic cut works for many customer applications where mill lengths are manufactured, or no additional fabrication is required. One of Formtech’s strengths is the capability to do additional, value added fabrication, both on an in-line and out-of-line basis. Many of the extruded products Formtech manufactures are components in OEM products. We strive to provide the extruded profiles completely finished when possible, including more sophisticated end cuts, holes, punch-outs and other fabrication that allows less labor and handling at your plant.
Fly Knife Cutter– Have you ever wondered how drinking straws are manufactured? These tiny tubes are extruded, and extrusion lines to manufacture these products run at speeds that can manufacture over 180,000 straws per hour. The only way to cut a plastic extrusion at this type of rate is to use what it commonly called a fly knife cutter. As the name suggests, the unit has one or more knives on a rotating wheel that cuts through the plastic extrusion as the wheel rotates. Many of these units are servo driven, meaning the blade can be extended to cut, and then retract at very high speeds. The blade, or blades, can also be fixed in an extended position to provide one or multiple cuts per revolution of the flywheel on the cutter. Fly knife cutters are typically used for small to medium size extruded profiles and can include cutter guides for very clean end cuts on the end product.
Digital Length Gauge– At Formtech, we would not consider our extrusion manufacturing facilities complete without digital read-out length gauges for our production and quality associates use during manufacture and inspection of your custom profile extrusion. We have this equipment in both the Fairview, PA and Athens, GA We believe that quality is defined by our customer’s expectations, and in the pursuit of superior quality, we emphasize the process of doing things right the first time. Extrusion dimensions are often measured in thousands of an inch, and we provide our teams with equipment that can accurately measure to this level. The operation of a digital length gauge is fairly simple. The measurement device is mounted to a very accurate set of linear rails, and the part is inserted onto the unit for measurement. One end of the plastic extrusion is held up to a fixed stop, and the rail on the opposite end slides along the linear rails until it contacts the other end of the extruded profile. The actual length of the part being measured is displayed on a digital read-out, with measurements showing to three or more decimal places. We involve and empower all our employees utilizing training, teamwork, and technology to the pursuit of superior quality. Pieces of equipment like the digital length gauges are tools we provide to back up this quality commitment.
We hope part two of our extrusion industry terminology review will help you better understand the extrusion process. Check back for parts three and four of our four-part series that will cover materials and processing.
We are anxious to work with you and your team on your next plastic extrusion requirement. Give us a call at 614-531-9954 or email at firstname.lastname@example.org for more information or a quotation.
Custom Plastic Extrusion Terms- Part One
Every industry has commonly used terms and acronyms, and custom plastic profile extruders are no exception. The extrusion industry tends to take these terms for granted, which can lead to confusion.
Formtech is going to help you understand our industry’s terms!
Please join us in a four-part series, looking at the top extrusion terms relating to each of the following categories:
Part One– Extruders and Tooling
Part Two– Downstream equipment
Part Three– Materials
Part Four– Processing
What is “custom profile extrusion”.
Think of extrusion in terms of an everyday product that almost everyone has seen – the extrusion of pasta using a pasta making machine. These devices make a wide variety of pasta noodle shapes, each using basic extrusion principles. In reality, whether you are making pasta or custom plastic profiles, the processes are very similar. Let’s look at 9 terms related to custom profile extrusion, all related to the extruder and the tool.
- Screw– Screws are the work-horse of the extruder. Extrusion, screws are not the typical screws you may see at your local hardware store. Instead, an extrusion line screw conveys, compresses, and mixes plastic compounds. Screw design for plastic extrusion is a sophisticated science, with specialty screw designs being developed to increase output rates, increase mixing, and widen processing windows. Screw designs may vary depending on the plastic compound, output requirements, and physical property requirements of the finished product.
- Single-Screw Extruder– As the name implies, a single-screw extruder has one screw, and was the first type of extruder developed around 1935 in Hamburg, Germany. Single-screw extruders are widely used today for processing a wide variety of plastic compounds and are considered a work-horse extruder for custom profile extrusion. Our Fairview, Pennsylvania manufacturing facility is outfitted with single screw extruders.
- Twin-Screw Extruder– Twin-screw extruders were developed in Italy after the Germans developed single-screw machines. Custom plastic extrusions are typically made on counter-rotating twin-screw machines while co-rotating twin-screw extruders are used primarily for compounding of plastic materials.
Counter-rotating extruders are designed to have the screws turn toward one another (one turns clockwise, the other turns counter-clockwise), and the screws are intermeshed to mix and convey the material down the extruder. There are two different types of counter-rotating extruders. A parallel twin-screw extruder has two parallel screws that are the same diameter from the beginning to the end of the screw. Conical twin-screw extruders have a much larger screw diameter in the back of the machine, and the screws taper as material flows toward the die. Both types of twin-screw extruders provide a tremendous amount of mixing and compression of materials.
Twin screw extruders are used for PVC Wood Plastic Composite materials(WPC), and other powder plastic compounds. Our Athens, Georgia manufacturing facility houses our high output, twin-screw extrusion lines.
- Extruder Size– Formtech has a variety of single-screw machines varying in size from ¾” to 3 ½”, which can accommodate profiles as small as 1/8” to over 8” in width. In general terms, the larger the diameter of the extruder, the more pounds per hour of output the machine provides. Twin-Screw extruders are typically measured in millimeters, and can vary widely in size depending on the extruded plastic profiles being manufactured. Formtech has twin-screw machines from mid-range up to large sizes, which can handle profiles as small as under 1”, up to 12” wide profiles that weigh more than 7 pounds per foot. The largest profiles manufactured by Formtech are used in marine applications such as a seawalls, or bulkheads. This product line is an innovative, hybrid sheet piling system made primarily of recycled PVC materials, with a prime, weather resistant capstock on all exposed areas. Check out the specifics at truline.com.
- Barrel– The barrel of the extruder is a hardened steel cylindrical cavity designed to house the extruder screw(s). The barrel is subjected to a considerable amount of pressure from compression of the plastic compounds during extrusion, and may either be simply hardened, or for high volume applications the barrel can be lined with harder materials such as tungsten carbide.
- Hopper– Plastic compounds are fed to the extruder through a hopper, which is basically a funnel to hold material as it is being either gravity or force fed to the machine. Generally, as the size of the extruder and output increases, larger hoppers are required to act as a reservoir for the plastic compound. At Formtech, our primary extruders are equipped with vacuum loaders, allowing our operators to focus on the quality of the custom extrusion instead of spending valuable time manually filling the hoppers.
- Adapter– Plastic materials exit the barrel and screw end, and are funneled into the extrusion die. The adapter allows the extrusion tooling to be mounted to the extruder, and transitions the material flow from the barrel & screw to a shape. The adapter can be a slide in configuration or can bolt on the head of the extruder. Slide in adapters provide ease of changeover from one extrusion die to the next, but are prone to leakage. Bolt on adapters take more time to change over, but provide a better opportunity for even pressure and reduced gate leakage. Many custom profile extruders utilize a series of standard adapters that can be used over a variety of extrusion tooling, to reduce tool costs and increase manufacturing flexibility.
- Die– Think of the extrusion die as the gateway to your finished profile. If you want angel hair pasta, you would not use a tool that looks like rigatoni. The extrusion tool is what determines the shape of the finished profile. Typically, a custom profile die is made up of several die plates, and will transition the general shape from the adapter to the finished shape of the extruded profile. This is called streamlining, and it is critical to the extrusion process to control tolerances. Have you ever made pasta and have certain strands not push out as quickly and evenly as others? This is due to improper streamlining, and the same holds true when manufacturing plastic extruded profiles. Many plastic materials are subject to degradation with heat, so smooth flow in the extrusion die is extremely important to eliminate burning during the production run. The streamlining in the die keeps plastic materials flowing, and helps prevent material degradation. The streamlined portion of the die feeds into the die land, which is the area of the extrusion tool where the material flows consistently across a section of the tool without streamlining. This land area stabilizes the material flow, and helps improve the surface finish of the extruded shape by “ironing” the outer surface of the profile. The point where the plastic compound exits the extrusion die is referred to as the die lip. It is important to keep the die lip flat and sharp, and this requires careful handling by the extrusion manufacturer. If this lip is damaged, it can result in irregularities in surface finish and appearance. Formtech maintains extrusion tooling at both manufacturing facilities with proper inspection, handling, and care. Formtech manufactures many of the extrusion dies we use to manufacture custom plastic products. We also utilize a global network of world-class tooling vendors for additional extrusion tooling support. To find out more about Formtech extrusion tooling, click here.
- Heater Bands– Precise temperature control is one of the processing musts in plastic extrusion. While the plastic material is in the barrel and screw of the extruder, a combination of friction heat and barrel heaters are used to carefully control the temperature of the extrudate. Once plastic compounds enter the adapter and die, external heaters are required to evenly control the compound temperature until the material exits the die lip. The die heaters can be as simple as strip heaters mounted to the extrusion die, or as sophisticated as custom made plates with flexible heater cords or even die inserts specially designed for the extrusion tool.
We hope the plastic extrusion terminology review will help you to understand the extrusion process. Check back for parts two, three and four of our four-part series.
We are anxious to work with you and your team on your next plastic extrusion requirement. Give us a call at 614-531-9954 or email at email@example.com for more information or a quotation.
Shutdown Reminder – Happy Labor Day!
On September 1, 2017 | by Formtech | in Blog
Formtech Enterprises will be closed on Monday, September 4, 2017 to observe the Independence Day holiday. All locations will reopen at the start of business on Tuesday, September 5, 2017. If you have questions about this schedule, please contact your sales or customer service representative or email us at firstname.lastname@example.org.
Have a safe and happy Labor Day weekend!
Fun Fact Friday – NBA Wears Plastic Bottles Thanks to Nike
Nike never ceases to amaze us–did you know that the famous Nike swoosh was designed by a female college student in 1971 for $35? How about that they are now the official partner of the NBA, taking over from Adidas? Recently, Nike revealed the new jerseys for the 2017-18 season, and each uniform contains about 20 recycled PET bottles. The uniforms are spun together with a combination of Alpha Yarns and recycled polyester which is not only environmentally friendly, but wicks sweat 30% faster than current NBA uniforms as Nike claims.
This isn’t the first time Nike has used recycled PET in jerseys. Since 2010, Nike claims to have diverted more than 3 billion plastic bottles including uniforms for the U.S. basketball team during the Summer Olympics and the U.S. Women’s soccer team in the FIFA World Cup. The manufacturing process uses 30% less energy by utilizing recycled polyester rather than virgin polyester, benefiting Nike and saving plastic from landfills each year.
It seems as though Nike has started yet another trend: Adidas is jumping on the recycled plastic bandwagon as well with the 2017 release of their “Parley” running shoes, using about 11 PET bottles throughout each shoe from plastic found in the ocean.
Click here for the article from Plastics Technology.