Intech Power-Core Thermoplastics Engineering Blog

Alexander Bartosch

Recent Posts

Quiet Gears Improve Patient Comfort and Imaging Quality in Medical Equipment

Posted by Alexander Bartosch on Jul 15, 2021 8:49:10 AM

If you have a medical exam or procedure that involves X-rays, mammography units or robotic surgery equipment, the last thing you want to hear is grinding gear noise. Noisy or vibrating motion systems are off-putting for patients and can compromise their comfort during an already stressful medical test. Not only that, motion chatter in the drives that move imaging equipment can also produce fuzzy images that aren’t suitable for diagnostic purposes.

Medical machines and imaging equipment require motion system components that are smooth and quiet. Whether you’re a medical equipment designer looking for the right part or a patient about to undergo a diagnostic test, with Intech Power-Core™ gears and cam followers at work, you don’t have to worry.

Our Gears Reduce Noise and Absorb Shock and Vibration in Critical Applications

Our Power-Core™ gears, which combine our proprietary polymer gear material with a metal core, have a unique balance of properties that make them well-suited to medical equipment applications. In addition to absorbing shock and vibration, compared to metals these gears reduce noise by up to 6 decibels, making them an ideal — not to mention less stressful — choice for point of care (POC) equipment. They are also suitable for X-ray equipment, mammography machines and other imaging systems due to their ability to eliminate motion chatter, which can compromise image quality in diagnostic tests. And, because our Power-Core™ gears are available with a stainless steel, non-magnetic core, they’re a safe option for magnetic resonance imaging (MRI) machines.

IntechPowerGears1Our Power-Core™ gears, which combine our proprietary polymer gear material with a metal core, are well-suited for medical equipment.

In one application, our engineers designed and delivered a gear that improved the image quality in a dental X-ray machine. In addition to providing precise control over the gear’s mesh engagement and backlash, our gear eliminated vibration, maintaining high image quality over time. Because they successfully eliminated fuzzy imaging due to motion chatter, our gears enabled the dentists to better diagnose and serve their patients. In another application, to provide patients with quiet, vibration-free comfort when moving in and out of MRI equipment, our iCam® followers were selected as wheels for moving patients’ platforms.

More Reasons Why You Should Choose Intech Gears

Their ability to absorb shock and vibration and reduce noise aren’t the only reasons our gears are an excellent fit for medical machinery. Unlike metal gears, our Power-Core™ gears don’t require lubrication, avoiding potential contamination caused by stray lubricants or metal particulates. Furthermore, the material has a low coefficient of friction, translating into higher torque transmission efficiency and allowing designers to select smaller drive motors. The gears also resist corrosion and commonly used sterilization chemicals, and they meet outgassing specifications for laboratory equipment applications that involve vacuum operation.

IntechPowerGears2Unlike metal gears, our Power-Core™ gears don’t require lubrication. The material also has a low coefficient of friction, translating into higher torque transmission efficiency.

In many instances — for example, in robotic surgery equipment — inertia is a factor when designing the gear train. Our Power-Core™ gears are seven times lighter than steel, significantly reducing inertia. And, if you’re worried about the polymer gears working, we’ll put your mind at ease. At Intech, we’ve developed a gear life calculation for our Power-Core™ gears. Over the last three decades, this calculation has proven itself to be a reliable predictive tool. Medical equipment manufacturers typically require five years of gear life. Using our gear life calculation, we can design gears that deliver on this demand. 

Even beyond the medical industry, our gears’ ability to absorb shock and eliminate motion chatter makes these components an ideal choice for any application that must retain superior imaging quality — from satellites to television equipment. And, we can produce our gears in a variety of types including bevel gears, helical gears, worm gears and more. 

IntechPowerGears3At Intech, we can produce our gears in a variety of types including bevel gears, helical gears, worm gears and more.

To learn more about how to design non-metallic gears for demanding applications that require quiet, vibration-free movement, are maintenance free and are supported by a solid gear life calculation, visit our product page. You can also contact our engineering department for a free consultation today.

 

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Sealed End-Cap Design Boosts Cam Follower Durability in Washdown Applications

Posted by Alexander Bartosch on May 27, 2021 4:25:26 PM

If you’re designing for packaging or processing machines in the food and beverage, pharmaceutical or electronics industries, then you might want to reach for cam followers that can endure frequent washdown cycles, resist contamination and corrosion and exhibit long wear life. At Intech, we offer several high-performance, greaseless iCam® Follower options for these environments. These options include:

  • A sealed bearing design that eliminates contamination sources.
  • Closed end caps that can withstand high-pressure washdown.
  • All-ceramic or hybrid ceramic ball bearings that don’t require sealing.

Intech1082.25" capped Intech iCam® Followers with a custom shaft.

Sealed Bearings and End Caps Withstand High-Pressure Washdown

Our iCam® Followers feature sealed bearings, as well as a self-lubricating, wear-resistant bearing surface — made from our Power-Core™ polymer material — that eliminates two potential sources of contamination often caused by metal cam followers: stray lubricant and particulates from metal-on-metal wear. In addition, the material does not absorb moisture, is resistant to aggressive chemicals and does not outgas in a vacuum. For these reasons, our iCam® Followers are a good choice for medical, semiconductor, food processing, liquid filling and cleanroom applications. And, our iCam® Followers have the added benefit of eliminating the time it takes to regrease moving components after washdown cycles.

Our cam followers are also available with an end-cap design. One side of the plastic roller is enclosed, or capped, protecting the precision ball bearings that are fitted into the polymer tire from contamination and high-pressure washdown solutions. If required, we can even seal the shaft; for example, a pharmaceutical company that wanted to guard against any potential grease leak from the bearings opted for this design. The cam followers with sealed end caps are also available with an eccentric shaft.

INTECH-capped-roller-shaft-sealed-with-O-ringConcave, capped iCam® Followers on a pharmaceutical processing machine.

Ceramic Ball Bearings Are Gaining Popularity in Hygienic Applications

Our iCam® Followers with sealed stainless steel bearings and shafts are a go-to choice whenever corrosion is likely. But you also have ceramic ball bearing options, which many customers who use more aggressive washdown solutions prefer. It’s worth noting, ceramic bearings do have a limited load capacity. However, if load isn’t an issue in your application, then these bearings will get the job done — and you don’t even need to enclose them.

In addition, ceramic bearings reduce friction and don’t rust, which is especially appealing for hygienic environments. You can choose either all-ceramic bearings or hybrid ceramic bearings, which combine ceramic ball bearings with a steel race to withstand some shock load. Our all-ceramic and hybrid ceramic ball bearings are available with or without lubrication and are sealed with Teflon®. Due to their ability to resist aggressive washdown cycles, these models are currently gaining popularity in many food and beverage applications, such as dairy plants.

Ready to Use iCam® Followers in Your Application?

Our iCam® Followers with sealed bearings and end-cap designs, as well as our ceramic options, are available in both inch and metric units. And, whether you select a cam follower with stainless steel, ceramic or hybrid ceramic ball bearings, our self-lubricating, polymer load-bearing surface extends your maintenance intervals, keeping your uptime high and reducing your overall costs.

Capped_iCamsiCam® Followers with end-cap design. The shape of the polymer outer racer can be designed to suit your application.

To learn more about your cam follower options for corrosive and contamination-sensitive environments, please contact our engineering team. Give us a call for a free consultation to explore how our iCam® Followers can benefit your application.

 

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Power-Core™ Gear-Drive Overcomes Belt-Drive Challenges in Frozen Food Slicing Applications

Posted by Alexander Bartosch on Apr 7, 2021 6:33:14 PM

Intech Power-Core Gear Systems

Slicing operations in frozen food applications are demanding, to say the least. They involve a constant switch between sub-freezing processing operations and hot washdown cleaning cycles, exposing components to thermal extremes. The nature of the cutting operation itself is also harsh and repetitive in nature, subjecting components to high shock and vibration loads.

Where traditional belt-driven cutting systems fail, our lubrication-free Power-Core™ gear systems shine. Despite the demanding nature of frozen food applications, our systems maintain consistent performance in cutting operations that involve frozen meat products, fruit, vegetables, frozen dough products and much more.

The Pitfalls of Traditional Belt-Driven Systems

Traditional belt-driven cutting systems often suffer extreme wear and a high failure rate due to repetitive start-stop stresses and temperature extremes between sub-freezing processing operations and hot washdown cleaning cycles. A high frequency of repetitive shock loads will cause the belt to stretch, leading to frequent tensioning, maintenance and production downtime. At the same time, the worn belts are prone to particulate instability, which is a potential cause of product contamination.

In addition, gears made from traditional plastics can wear prematurely. They also experience dimensional instability caused by moisture absorption, as well as variations in tensile strength within the freeze-thaw cycles. These dimensional changes, along with the physical properties of the gear material itself, can result in tooth cracking, breakage and wear in the presence of shock and vibration loads. Additionally, the frequency of these loads can wear out the keyway cutout in the all-plastic gear, causing the gear to wobble and eventually fail. Together, these problems often lead to frequent line stops in order to apply additional lubrication or to conduct emergency repairs.

Intech Gears Overcome Frozen Food Challenges

In contrast to belt-drive systems and all-plastic gear drives, our Power-Core™ gear systems feature a non-hygroscopic, dimensionally stable composite material with a cast-in metal core that is not affected by sub-zero temperatures, shock loads or harsh washdown chemicals. The corrosion-resistant stainless steel core provides safe, secure attachment to the shaft, assuring reliable torque transmission. These gears also maintain consistent performance despite the high-torque, repetitive nature of cutting operations.

Power-Core™ gears, which don’t require any external lubrication, also avoid the pitfalls of contamination caused by lubricants or particulates, making them well-suited for use in high purity food-cutting and packaging operations.

To get started, our engineers use a proprietary durability calculation to take the risk and guesswork out of converting existing belt designs or all-plastic gears to Intech Power-Core™ drives. Contact us today to get started.

 

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Long-Lasting, Lubrication-Free Guide Rollers Enable Flexible Automation for Genomic Research

Posted by Alexander Bartosch on Apr 7, 2021 6:03:01 PM

When it comes to life science and laboratory instruments, your choice of motion components can make a big difference in terms of performance. As a testament to this fact, a biotechnology company that specializes in detection and imaging equipment outfitted one of its automated liquid handling systems with Intech polymer guide rollers. Compared to previous motion components, these guide rollers have unlocked a number of benefits, including long, wear-free service life, which has helped improve the speed and performance of the dispensing system.

Intech Guide Roller

About the Liquid Handling System

The biotechnology company’s liquid handling system is ideal for applications that involve sample preparation. It features a gantry-type dispense arm, as well as tools that accommodate solid phase extraction and magnetic bead separation. Thanks to this flexible workstation, users can extract and purify genomic DNA, RNA and Plasmid DNA, as well as polymerase chain reaction (PCR) and sequencing setup and cleanup. Users can also configure their workstations based on different variables, including the size of the instrument, pipetting arm technology and labware movement.

Other benefits of the workstation include:

  • The ability to switch between nanoliter and microliter dispense heads in seconds
  • Precision pipetting with a wide dynamic volume range
  • On-the-fly adaptability in dynamic volume range
  • Microplate densities up to 1,536 wells
  • The ability to adjust throughput and capacity, as well as integrate accessories to enable greater automation

Taking Performance to the Next Level With Intech Guide Rollers

A key component of the workstation is its integrated Cartesian robotic system. This robot provides motion in the X, Y and Z axes and must maintain high accuracy and repeatability over many move cycles. To help them achieve these goals, the company’s design engineers selected Intech guide rollers. Made from our proprietary Power-Core™ polymer material, these guide rollers are a critical part of the motion system, which enables researchers to use the workstation to test thousands of samples in a fraction of the time it takes lab technicians to test only a few.

Intech-Pic-1-Guide-Roller

Self-lubricating and wear-free design. The Intech guide roller, which supports the front of the robotic arm, rides on a stainless steel rail that is external to the system. It provides a very smooth rolling surface without any lubrication, which is necessary for clean environments. The guide roller also avoids compression set and has been tested to show no signs of wear—even after extended life cycles. 

Zero flat development. Plastic materials have the tendency to develop flat spots when they are at a standstill under static loads. A flat spot usually means the end of the guide roller’s life. In contrast, Intech’s engineered polymer, which the guide rollers are made from, features a highly crystalline structure, enabling it to withstand high loads. For this reason, our guide rollers and cam followers can sustain high static loads over prolonged periods of time without developing permanent flat spots.

Stability under varying conditions. Ideal for the biotechnology workstation, Intech guide rollers are precision-machined, enabling the robotic arm to move with precision. The Power-Core composite material also maintains its dimensions under varying conditions, which is a critical feature for the accuracy and repeatability of the operation. In addition, the material does not absorb moisture, is stress-free and retains elasticity over its entire temperature range: -40° to over +160°F.

Enabling Flexible, Reliable Sample Preparation

Compared to our Power-Core guide rollers, the components the biotechnology company originally selected to support the front of the robotic arm were made from a softer compound that did not offer the reliability required by the instrument. Although switching over to our guide roller was a small design change, it improved the speed and performance of the motion system.

By selecting a guide roller with a long service life and lubrication-free operation, the workstation can now continue to fulfill the needs of the scientific and research communities.

To learn more about Intech guide rollers and our Power-Core material, please visit our product page.

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Precision Track Rollers Beat Metal and Plastic To Hold Up 1,280-Pound Glass Door

Posted by Alexander Bartosch on Apr 6, 2021 10:37:31 AM

High-quality sliding doors are expected to open easily and quietly—a motion that largely depends on high-quality track rollers. Unfortunately, many materials used in door hardware fall short. For example, metal track rollers will wear out the aluminum rails typically used in sliding door installations. These rollers are also noisy. On the other hand, ordinary plastic rollers lack dimensional stability and can fail when exposed to real-world static and dynamic loads, temperatures, moisture or chemicals. Another challenge for sliding door applications is the weight of the door itself. 

In one application, a storefront supplier needed to design and install a sliding glass door that was five times heavier than the average door. Despite the heavier weight, the door needed to operate smoothly and safely with no maintenance. Fortunately, Intech track rollers were up to the challenge.

Meeting the Requirements of a Large Glass Sliding Door

Whether metal, wood or glass, providing the right materials for a storefront can be difficult. Not only must the storefront meet the customer’s unique vision, but the door, framing structure and other components must be easy to install and operate smoothly. In one application, a storefront supplier needed to install a sliding door system consisting of a large tempered glass panel. This panel, which was 10-feet wide, 20-feet high and 1.5-inches thick, weighed in at 1,280 pounds. The goal was to be able to slide the glass panel easily and smoothly in and out of place.

Metal track rollers were not an option because they require periodic lubrication, produce more friction and noise and easily wear out aluminum rails. Plastic or nylon components were also not an option, as they often fall short of the proper load capacity and can easily develop flats under prolonged static loads.

Standard sliding door hardware includes the rail, two-wheel trolleys and mounting hardware. Two trolleys, which are required to install a door panel, will carry doors up to 400 pounds easily and quietly. Additional trolleys can be added for heavier doors.

Power-Core™ Rollers Improve Sliding Door Performance

Intech track rollers overcome the challenges associated with metal and plastic door hardware. Unlike metal track rollers, the self-lubricating, precision-machined plastic tires in our Power-Core™ polymer track rollers require no lubrication and eliminate costly maintenance. The high-quality ball bearings encapsulated by the tire are also lubricated for life, and the composite tires absorb shock and vibration, don’t wear out aluminum rails and can run up to 10-decibels quieter than comparable metal track rollers.

Heavy Duty Door Trolley

In addition, our Power-Core™ track rollers:

  • Rotate with low runout, reducing noise and enabling easy rolling

  • Maintain dimensional stability and avoid swelling if exposed to moisture

  • Feature a crystalline molecular structure that makes it highly resistant to the compressive forces that cause flat spots

  • Exhibit lower rolling resistance than metals

  • Resist chemical degradation

  • Are available with stainless steel bearings and cleanroom-approved lubricants.

The heavy-duty door trolley.            

After our Power-Core™ track rollers performed well under tests, we designed a special shaft to incorporate into the track rollers for easy installation. Applying years of experience in designing heavy-duty guide rollers and cam followers for demanding industrial applications, our engineers designed the plastic-encased ball bearings to last over 100 million rolling cycles.

After we delivered the components, the storefront supplier performed additional tests using the semi-custom rollers, and our components performed perfectly. Once the door hardware was in place, the massive 1,280-pound glass panel could be moved safely using only one finger.

Learn More About Power-Core™ in Sliding Door Applications

Power-Core track rollers combine a polymer bearing surface with top-of-the-line roller bearings, avoiding the pitfalls of all-metal or plastic door hardware. Other sliding door applications include train doors, subway station doors, airport people movers and commercial buildings—to name a few. And, we can customize the rollers’ size and profile, as well as the shaft, to your door rails and mounting hardware.

To learn more, please visit our product page.

 

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Greaseless Cam Follower With Hybrid Design Excels in Washdown Applications

Posted by Alexander Bartosch on Nov 11, 2020 3:59:03 PM

The wrong type of cam follower or roller can lead to contamination issues, frequent maintenance and reduced service life—especially in washdown applications. This is an especially important concern now that washdown chemicals have become more caustic under the FDA Food Safety Modernization Act (FSMA). In these environments, even traditional all-metal stainless steel cam followers are subject to corrosion and accelerated metal-to-metal wear, leading to premature failure.

Fortunately, you have another option in the form of a hybrid design. This maintenance-free cam follower combines a polymer load-bearing surface with stainless steel, ceramic or hybrid-ceramic ball bearings, enabling the cam follower to withstand even the harshest conditions.

Capped_iCams

The Power of Power-Core™ iCams®. Example: Capped cam follower

The Power of Power-Core™ iCams®

Bear in mind, not all plastics will be equally suited for use in cam followers and guide rollers in washdown environments. With over 35 years of design experience, our engineers have selected polymers for washdown applications that can be precision machined, are dimensionally stable and don’t swell in moisture. These polymers are also highly resistant to chemicals and temperature fluctuations and exhibit excellent wear properties. Whereas traditional cam followers are subject to corrosion and wear, our Power-Core iCams® don’t corrode at all, making them a good fit for washdown applications, outdoor exposure and other harsh environments.

Eliminate Contamination From Grease and Metal Particulates

Intech iCam®Fitted with sealed bearings, iCams’® self-lubricating, highly wear-resistant bearing surface eliminates two potential sources of contamination: stray lubricant and particulates from metal-on-metal wear, both of which could contaminate your product.

Needle bearings in metal cam followers require frequent lubrication because washdown liquids can wash off the grease from both the cam follower, as well as from the rail or cam that the cam followers are running on. Lack of lubrication can significantly reduce the cam followers’ wear life. To eliminate this need for lubrication, Intech polymer cam followers feature sealed ball bearings, which are pre-lubricated for life. And the metal surface the iCams® are running on doesn’t have to be lubricated either. Thanks to this design, you can start your machine immediately after washdown, saving regreasing time.

In addition, the wear-resistant polymer outer racer doesn’t wear the metal surface it’s running on, preventing the generation of metal particulates. This is a frequent and highly undesirable source of particulates contamination with metal cam followers—especially in food, beverage or pharmaceutical applications. For these reasons, iCam® polymer cam followers and guide rollers are an excellent replacement for metal cam followers—including stainless steel—in filling, packaging or processing machines used in food, beverage or pharmaceutical applications, electronics assembly and other hygienic environments. Satisfied customers testify that Intech iCams® often outlast the metal cam followers they replaced.

Save on Maintenance and Downtime

Besides saving on lubrication and avoiding product contamination, Intech iCams® offer additional savings by eliminating the need to replace worn metal components in contact with metal cam followers due to metal-to-metal wear. Insufficient lubrication between washdown sessions often accelerates this wear process.

For example, replacing a cam in a food processing or packaging machine—especially outside the scheduled maintenance window—can lead to prolonged downtime and production losses, not to mention all the maintenance overtime to minimize the lost production time. iCams® don’t wear out the metal surfaces on the machine components they’re running on, saving all the costs associated with replacing them and extending maintenance intervals.

Remember Your Bearings

And don’t forget, your choice of bearing matters too. iCams® with sealed stainless-steel bearings and shafts are the traditional, go-to choice whenever corrosion is likely. You also have ceramic options, which are preferred by customers who use more aggressive washdown solutions. These ceramic bearings reduce friction, feature a high static load capacity and don’t rust, which is especially appealing for hygienic environments. Two types are available, all-ceramic or hybrid ceramic bearings, the latter of which combines ceramic ball bearings with a steel race. The hybrid type can also withstand some shock load. Despite their many benefits, however, ceramic bearings tend to come with a hefty price tag compared to stainless steel.

Reap the Benefits of Higher ROI

The precision ball bearings used in iCams® exhibit low rolling resistance compared to externally greased needle bearings in metal cam followers. Over-greasing leads to more rolling resistance and often to skidding—another cause of wear. In machines with several dozens of cam followers, low rolling resistance will result in lower drive power requirements and energy savings. iCams® also weigh about 40-percent less than traditional cam followers. The lower weight and rolling resistance enable our customers to increase their line speeds and line output. Higher line speeds, combined with all the other savings iCams® offer, deliver higher ROI to our customers.

Intech Corrosion and Wear-Resistant iCams®—Designing for New or Existing Machines

At Intech, whether we work with design engineers on new equipment or maintenance engineers on existing production machines, we’ve found that we can design our way around the problems associated with washdown, moisture and other environmental factors by picking the right type of polymer and bearing combination. If our standard cam followers aren’t a good fit for your application, we can design one that will. For example, we designed a capped iCam® that can handle high-pressure washdown.

To learn more about your cam follower options, please contact our engineering team. We’re also happy to verify the iCam's® load capacity and estimated lifespan in your application—free of charge. Ask us about samples for testing. Our standard iCam® sizes serve as drop-in replacements for metal cam followers, including stainless steel.


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5 Advantages of Plastic Rack and Pinions in Motion Applications

Posted by Alexander Bartosch on May 21, 2014 4:00:00 PM

 Polymer Eliminates Contamination in Linear Motion Systems 

In an ideal world, linear motion systems would run only in squeaky clean operating environments. In the real world, linear motion systems usually have to run in plants with varying degrees of contamination, chemical exposures or moisture. These less-than-ideal conditions can shorten the lifespan of linear motion systems that rely solely on metal drive components—particularly rack-and-pinions.

KLEENLine conveyor with Intech Gear self lubricating rack and pinion

(Pictured Above: Intech Power-Core™ Gear and Stainless Steel Rack in a High Speed Retractable Bakery conveyor - Read More Here )

To meet the challenges posed by real-world operating conditions, we have designed and delivered many rack-and-pinion systems based on our Power-Core™ polymer.  Typically these consist of an Intech Power-Core™ gear with a stainless steel core and a stainless steel rack, though some applications have been best served by a Power-Core rack and a stainless steel pinion. 

Either way, we’ve found that use of polymers has five key advantages in rack-and-pinion applications:

  1. Eliminates lubrication. As a self-lubricating polymer, Power-Core™ does away with the need to apply lubricants over the life of the rack and pinion. The elimination of lubricant eliminates a key source of contamination in sensitive applications such as packaging, pharmaceutical, semiconductor or food processing. 
  2. Extends wear life. Power-Core and stainless-steel together offer an extended wear life and typically last for several years longer than all-metal designs. The user of Power-Core has also allowed us to create some design features that further extend wear life—such as pitch line control feature prevents pinions from bottoming out.
  3. Prevents corrosion. Traditional rack and pinion designs with metal gearing are subject to rust and corrosion, particularly in washdown applications. As a polymer, Power-Core does not corrode at all.
  4. Remains dimensionally stable.  Thanks to the physical properties of its base polymer, Power-Core does not suffer from dimensional and tensile property changes that affect conventional polymers when exposed to moisture, chemicals or elevated temperatures. Power-Core's base polymer has one of the lowest moisture absorption rates of any engineering plastic. Power-Core stands up to a wide range of industrial chemicals.  And Power-Core exhibits about 50% better high-temperature performance than comparable engineering polymers. 
  5. Improves motion control. Power-Core can produce rack-and-pinions that operate both smoothly and quietly as the rack moves back and forth, reducing noise by about 6 dBa compared to all meal components. The reason is that polymer has intrinsic vibration and shock load damping properties.  Power-Core components also weigh about 85% less than a comparable metal component. In motion applications, this weight reduction translates directly to reductions in moving mass and inertia.

Rack-and-pinions based on plastics components do have to overcome the perception that they won’t be as durable or carry the same loads as the all-metal designs familiar to motion control engineers. However, we’ve proven that perception false time and time again. 

Our experience with gear design and predictive analysis has allowed us to design polymer rack-and-pinion systems that can and do outlast all-metal designs in highly-loaded applications. To learn more, give us a call.

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Tags: rack and pinion system, self-lubricating gears, gear design, r gear life calculation, custom gear design

Power-Core Plastic Components Take On Metals

Posted by Alexander Bartosch on Feb 27, 2014 8:17:00 AM

Even with all the advances in engineering polymers and processing methods, metal alloys still dominate the production of large parts used in power transmission and structural applications. And that dominance makes sense. Metals not only have the strength to withstand heavy loads over time but also have the advantage of familiarity. Most engineers know how to design with metals and how metals fail. Plastic properties can seem obscure in comparison.

It’s time, however, to shed some light on the capabilities of plastics in large part applications. Plastics can outperform metals in these some of these applications—but only under a very specific set of conditions:

  • Mechanical Properties Are Within Reach. To be sure, some large part applications have extremely high mechanical and thermal loads, which can rule out plastics of any kind. But don’t count out plastics prematurely. We have delivered larger polymer structural parts and power transmission components that withstand continuous forces of several metric tons. The key to these heavily loaded applications is picking the right material and manufacturing method. Our approach to large parts relies on a proprietary nylon material that we gravity cast. It has significantly different—and higher—strength properties than seemingly similar injection molded or cast polymers

  • The Application Requires Special Properties. No engineer in his right mind will replace a proven metal component with a plastic one—unless he has a good reason. Premature failure due to wear or corrosion represent two of the most common reasons to replace metal components with a high-performance plastic. The right plastic can eliminate wear altogether and resist corrosive environments in ways that metals cannot. Weight reduction is another good reason, since polymers like our Powercore (TM) weigh about 7x less than steel. The weight reduction comes in handy in many transportation applications where every ounce counts or in high-speed machines that have difficulties with inertia mismatches. Still other special properties revolve around the electrically and thermally insulatative properties of polymers.

  • Plastics Have To Cost Less. Plastics components often cost less than their metal counterparts, though their cost advantage is not always straightforward. Our Power-Core nylon material, for example, does not always offer an immediate cost reduction compared to metals. In fact, sometimes it costs more to produce the plastic component if it’s replacing a simple machined steel part. But the cost advantage will tip in favor of polymers over time whenever metal components fail prematurely due to wear or corrosion. Polymers also gain an advantage whenever they produce significant process advantage—such as higher speed or unit cost savings.The polymer component may also cost less because it eliminates the expensive lubrication needed to keep metal components running. When polymer components replace more complex metal parts, as opposed to a simple part, the cost reduction can be immediate. The reason boils down to a manufacturing edge. Polymer components can often be produced net-shape or near-net-shape, so they can cost less to produce then complex metal components that require multiple fabrication steps. A single casting can often replace multiple metal parts, producing more savings.

  • Polymer Properties Must Scale Up. A polymer’s physical properties won’t typically change with the size of the part. For example, a polymer that resists moisture will do regardless of part size. The inherent physical properties, however, paint only half the picture. Some polymer properties will change with size due to the influence of the processing method. Our gravity casting process, for example, can produce large parts without the internal stresses you would find in a high-pressure processing method such as injection molding. This low stress state is largely due to the resulting dense crystalline structure in the cast part as well as the gradual cooling in the mold. The low stress state allows the cast parts to remain dimensionally stable regardless of size. Indeed, we have produced parts that measure several meters across that have essentially the same dimensional stability parts measuring a few centimeters.

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Tags: PA12GC, cast nylon 6, nylon 66, delrin alternative, gluing delrin, plastic welding, Nylon 6 Alternative, Cast Nylon Alternative, PA12G alternative, PA12C Alterative

Large Cast Power-Core (TM) Propeller Dives Into Paper Pulp Mixing

Posted by Alexander Bartosch on Feb 20, 2014 8:00:00 AM

Most engineering polymers won’t stand up to the harsh conditions found inside the mixing tanks used in pulp and paper processes. High shear forces, elevated temperatures, aggressive chemicals and continuous wear can mean an early death for ordinary polymer pumps and impellers. And in fact, internal mixer components are typically made from expensive stainless steel grades or platings, not plastics.

Our Power-Core(tm) PA12GC Gravity Cast monomer, however, is different than other engineering plastics, and it has emerged as a emerged as a cost effective alternative to composites and metals in tank propeller applications. This ability to withstand the challenging conditions found in pulp and paper processing also makes Power-Core(tm) a natural fit for other types of mixers and processing machines.

 

Power-Core(tm) has four key characteristics that allow its use in these propeller applications:

  • Resists Aggressive Chemicals. Power-Core resists the strong acids and bases found in pulp and paper processing. As a result, the material avoids the environmental stress cracking and brittle failure that would put an end to propellers made from less capable plastics.

  • Fights Wear. Because of their continuous contact with viscous liquids, mixer propellers tend to suffer from hydroabrasion. Power-Core has an innate resistance to this wear mechanism.

  • Scales Up. The propellers measure 1,500 mm across. So none of Power-Core’s chemical and wear resistance would make much of a difference in this application if the material didn’t lend itself to large structural parts. Regarding size, Power-Core’s proprietary gravity casting process can produce stress-free parts that measure more than 3 meters across. What’s more, the Power-Core gravity casting process allows the polymer to be cast over structural steel parts. The propellers, for example, have a structural steel hub to optimize the power transmission from the shaft to the blades.

Costs Less. No one would replace steel propellers unless there was a clear advantage to polymers. Power-Core has just such an advantage in the form of a longer life than steel, which tends to give into hydroabrasion prematurely. Power-Core also has a manufacturing advantage in that it can be cast net shape, eliminating expensive machining and finishing operations required by stainless propellers.

 

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Tags: PA12GC, paper pulp mixer, plastic for paper pulp, Voith plastic parts, cast nylon 6, PA12G alternative, PA12C Alterative

Modified Plastic Gears For Electronic Power Steering (EPS) Systems

Posted by Alexander Bartosch on Feb 13, 2014 8:00:00 AM

At the beginning of the 1990s Electronic power steering was just beginning to hit the main stream. Delphi - since bankrupt was on the forefront of the R&D. During a ten year period numerous tests were made with plastic gears as a choice for EPS systems. Power-Core(tm) PA12 Cast Nylon plastic gears were among the top finalists.

The polymer properties of Power-Core(tm), in particular the ability to cast and mechanically bond the polymer around a metal core - aluminum, steel or brass - and insure optimum power transmission with minimum creep. The shock dampening qualities of the material allow the gears to withstand both curb shocks and obstacle ride overs. The natural tendency of the material to  return to its natural position also adds to the quality of driver feel as noticed in cornering and general steering response.

In recent months we have had a number conversations on the topic of electronic steering, the core problems seems to be the same now as they were in 1990. Unfortunately, with more performance automobiles, namely the Porsche 911 and electric cars, moving to electronic steering we are excited to have a renewed interest in our power-core plastic gears and as car people look forward to one day driving a car that we can be certain has the best electronic steering possible.

Tags: EPS, Electronic steering gear, Column Steering Gear, Electronic rack and pinion steering gear