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Elasto Proxy's Sealing Solutions Blog

Elasto Proxy's Sealing Solutions Blog is the place for conversation and discussion about the design and custom fabrication of rubber and plastic components. For nearly 25 years, our family-owned company has provided high-quality, low-volume seals to a variety of industries. Doug Sharpe, Elasto Proxy's co-founder, is a former president of the International Sealing Distribution Association (ISD), a not-for-profit trade association that enhances member success through information, education, and interaction. By blogging for CR4 in this same supportive and collaborative spirit, Doug and other members of the Elasto Proxy team will share our experiences with you.

Industry 4.0 for the Real World

Posted May 15, 2018 4:55 PM by Doug Sharpe

Industry 4.0 is a catchphrase and buzzword that you can no longer afford to ignore. This fourth phase of the Industrial Revolution isn’t just about the increased digitization of manufacturing. It’s not just about advances in automation either. Industry 4.0 could change how your company competes and whether or not you’ll continue to win. Industry 4.0 isn’t just about technology. It’s about profitability.

What Is Industry 4.0?

Industry 4.0 is a term that most manufacturers recognize, but that few can fully define. The media hype doesn’t help. The fact that manufacturing experts have different definitions adds to the confusion. For the purposes of this article, we’ll define Industry 4.0 as a family of technologies that use a cyber-physical interface to improve how humans and machines interact in order to add business value.

Which technologies are part of the Industry 4.0 family? Here’s what we’re including:

  • Robotics and advanced human-machine interfaces
  • The Industrial Internet and the Internet of Things (IoT)
  • Big Data and cloud computing
  • Simulations and augmented reality
  • Horizontal, vertical, and customer system integration
  • Additive manufacturing (3D printing)
  • Cybersecurity

Unfortunately, some of these “family members” are also buzzwords whose meaning has been diluted by misuse and overuse. There’s also a common misunderstanding that Industry 4.0 is revolutionary because it’s about the digitization of manufacturing or the use of automation. Remember: neither digitization nor automation are new. What’s revolutionary is how they’re being used together – and with people.

Smart Factories and Warehouses: Three Examples

Let’s look at some examples of Industry 4.0 in the real world.

Harley Davidson is an iconic motorcycle manufacturer that consolidated operations from 42 old buildings into one new factory. The company’s York, Pennsylvania facility uses digital control systems, automated guided vehicles, tablet PCs, and wireless digital signage. This facility has reduced production cycles from a fixed 21-days to a six-hour horizon. Worker injuries are also down by 91%.

General Electric is a multinational conglomerate with roots that reach back into the nineteenth century. At its gas turbine plant in Greenville, South Carolina, GE uses advanced manufacturing equipment with sensors, industrial networks, and advanced software for data analysis. Thanks to these investments, GE’s smart factory realized a $100 million productivity savings across the entire facility in three years.

Knapp AG is a German logistics company that has developed a human-machine interface for picking. Workers wear a headset with an integrated camera and see-through display. The camera captures serial and lot numbers for real-time stock tracking. The headset presents workers with item information and lets them keep both hands free for picking. This human-machine interface has reduced error rates by 40%.

How Industry 4.0 Drives Value

As these examples show, Industry 4.0 isn’t just about new technologies. It’s about getting business value from these investments. According to McKinsey & Company, a worldwide management consulting firm, Industry 4.0 provides options, or “levers”, for value drivers – anything that can be added to a product or service to increase its value to customers. This table explains.

Value Drivers

Industry 4.0 Levers

Resource / ProcessSmart energy consumption

Intelligent lots

Real-time yield optimization

Asset UtilizationRouting flexibility

Machine flexibility

Remote monitoring and control

Predictive maintenance

Augmented reality for maintenance, repair, and operations (MRO)

LaborHuman-robot collaboration

Remote monitoring and control

Digital performance management

Automation of knowledge-work

InventoriesBatch size

Real-time supply chain optimization

On-site 3D printing

Supply / Demand MatchData-driven design to value

Data-driven demand production

QualityDigital quality management

Advanced process control

Statistical process control

Time to MarketRapid experimentation and simulation

Concurrent engineering

Customer co-creation / open innovation

Service / After-SalesPredictive maintenance

Remote maintenance

Virtually guided self-service

Industry 4.0 and You

According to the Boston Consulting Group, a majority of larger manufacturers (53%) see the adoption of Industry 4.0 as a priority. Yet a sizable percentage of smaller companies are uncertain about what Industry 4.0 really means. Unsurprisingly then, approximately one-third of smaller manufacturers (34%) do not have plans to develop or implement an Industry 4.0 strategy.

Is your company ready for Industry 4.0? What are you doing about this fourth phase of the Industrial Revolution? Are you considering specific technologies? Maybe you’ve implemented some aspects of Industry 4.0 instead. Regardless of where you are in your journey, we hope this article has been helpful. We also invite you to share your thoughts by commenting on this blog entry.

1 comments; last comment on 05/16/2018
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Bulb Trim Selection Tips

Posted April 30, 2018 7:57 PM by Doug Sharpe

Bulb trim provides sealing and insulation for doors, hatches, and enclosures with rounded corners. These industrial rubber products have separate bulb and retainer sections, each of which can have a different durometer or hardness. The bulb forms a seal under low-to-medium closure force. The retainer or trim is pressed into place over a flange and may have an integral tongue or metal clips to promote attachment.

Elasto Proxy supplies a wide variety of bulb trim seals and can custom-fabricate finished gaskets that save time and money on your assembly line. In this article, you’ll learn how to choose the right bulb trim for your application. Whether you work in engineering, procurement, or production, compound selection and part dimensions are critical. Product features vary, too.

Compound Selection

Do you need bulb trim that’s made from a specialty material, or can you use a commercial-grade rubber instead? Compounds that are commercial-grade usually cost less than specialty rubber. That’s because specialized compounds meet standards, approvals, or regulatory requirements that can be challenging to attain. Specialty rubber usually has higher minimum order quantities (MOQs), too.

Compound selection also means choosing an elastomer that can withstand the application’s environment. What is the temperature or range of temperatures? Is there exposure to wind, water, chemicals, or fire? It’s also important to choose a rubber that resists compression set. Otherwise, the bulb won’t “bounce back” to its original thickness after a compressive force (such as closed door) is removed.

Typically, the bulb portion of a bulb trim is made of either EPDM rubber or a thermoplastic elastomer (TPE). EPDM provides excellent resistance to weather, ozone, aging, water, and steam. EPDM also remains flexible at low temperatures. TPEs are also weather-resistant, but these materials are recyclable and support extensive color-matching. TPEs are more expensive, however, so remember to consider the costs.

The retainer or trim portion of a bulb trim seal is often made of polyvinyl chloride (PVC), a polymer that maintains its flexibility at lower temperatures and resists kinking. PVC also offers excellent impact resistance and good abrasion resistance. PVC isn’t the only retainer material that’s available, but it’s a versatile choice that’s suitable for many applications.

Product Features

Most industrial rubber products are black, but bulb trim can support distinctive designs. That’s why Elasto Proxy offers profiles that come in colors such as white, off-white, beige, tan, and gray. We can also source metallic-colored TPE profiles and supply bulb trim with specific textures. Many industrial rubber products are flat and smooth, but bulb trim with coarse, pebbly, or ribbed finishes are available.

Some bulb trim features an integral tongue, but the retainer section of the seal can include a metal clip instead. This aluminum or steel clip promotes permanent gripping under demanding conditions such as the repeated opening and closing of a door, enclosure, or hatch. The retainer portion of the gasket may also support the use of a hot-melt adhesive for fastening.

Part Dimensions

Finally, it’s important to choose bulb trim with the right bulb size, gap, and bend radius. To determine the bulb size, measure the distance between the door and the jam when the door is closed. Then add between 25% and 50% to account for compression. Do not add a larger amount. Over-compressing the bulb won’t create a better seal. In fact, it may reduce seal life and result in compression set.

The gap or edge thickness for the retainer section also requires accuracy. As a rule, choose a bulb trim where the gap equals the flange. For example, choose a bulb trim seal with a gap of 1/2” for a flange that’s 1/2” wide. If you choose a bulb trim with a larger or smaller gap, the seal may leak. The wrong bend radius can limit sealing performance, too.

If the angle in the bend radius is too large, recesses or valley may form and allow the passage of water. If the angle is too small, kinking may occur. Choosing the right bulb trim can help you to avoid these problems, but mistakes during installation can also limit gasket performance. That’s why Elasto Proxy supplies custom-fabricated rubber products that arrive on your assembly line ready-to-install.

Choose Bulb Trim from Elasto Proxy

Do you need bulb trim for doors, hatches, or enclosures with rounded corners? Elasto Proxy is ready to answer your questions about compound selection, product features, and part dimensions. We can also fabricate custom solutions that help you to reduce material waste, speed installation times, and improve overall quality. To get started, contact us.

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The True Costs of Industrial Rubber Products

Posted April 16, 2018 6:06 PM by Doug Sharpe

What are the true costs of industrial rubber products such as seals, gaskets, and insulation? Buying rubber materials and fabricating them in-house may seem cost-effective, but is your company really saving money? For that matter, are you sacrificing quality, consistency, and potential sales opportunities for a questionable cost savings?

Companies that want to know the true costs of industrial rubber products need to understand the full scope of their manufacturing costs. Typically, these costs are divided into three categories: direct labor, direct material, and manufacturing overhead. If any of these costs are incorrect, your financial statements may under-report inventory value and the cost of goods sold.

In this article from Elasto Proxy, we’ll examine each category of manufacturing costs so that you can consider how your in-house operations compare to outsourced fabrication. By understanding your true costs, you can make better business decisions and strengthen your manufacturing operations.

Direct Labor

Direct labor is the cost of the wages of the workers who are physically involved in converting rubber materials into finished products. This category of costs doesn’t just include time spent on activities such as cutting and bonding. Direct labor also includes the cost of retrieving materials from inventory, moving them to your assembly area, and preparing for manufacturing operations.

Let’s say you need to cut some acoustic insulation from sheet materials. If you keep this material in stock, a worker must retrieve it from a warehouse and move it to your assembly line. Another worker creates a stencil or template for the part and positions sheet material on a table. This second worker then uses the template and a handheld knife to cut each part from the sheet. All these tasks take time.

Direct labor also includes the cost of rework. Naturally, parts that are challenging to cut increase the likelihood of human error. Workers may struggle to cut clean circles, straight edges, small through-holes for fasteners, blind holes for raised fastener heads, or chamfers with 30° or 45° angles. For a water jet cutting machine, however, these are easy cuts to make.

The true costs of direct labor aren’t limited to cutting either. In the case of a mobile equipment manufacturer, direct labor can include the cost of spraying an adhesive to the cabin so that acoustic insulation will adhere. This process can incur substantial setup and cleanup costs. If you buy taped gaskets instead, you can reduce these costs while eliminating worker safety and environmental concerns.

Direct Materials

Direct materials are the cost of the materials that become part of the finished product. In our example with acoustic insulation, this is the cost of the sheets and the adhesive. With rubber gaskets such as door and window seals, direct materials are the lengths of rubber that workers cut and the bonding material (such as glue) that’s used. In both examples, the amount of waste may be more than you realize.

Workers who cut sheets may not trace the outlines of parts in the most efficient manner. Gaps between the edges of parts remain unused and are material waste. Across a volume of parts, the amount of wasted material can be significant. In fact, cutting the same part twice will double your direct material costs. Plus, if a worker discards a poorly-cut length of rubber, you may never know it’s in the trash.

Across many jobs, direct material costs can have enterprise-level consequences. Generally, companies don’t want to tie-up cash by ordering more materials than they really need. Depending on the amount of rubber that’s wasted, you may be ordering overages that can really add up. This affects your cash flow and, potentially, your ability to allocate resources elsewhere.

With outsourced industrial rubber products, you pay for the materials that you need. There are minimum order quantities (MOQs), of course, but there are also MOQs if you buy the rubber yourself. Unlike manual cutting, water jet cutting supports the nesting of parts for maximum material yields. This digital manufacturing process also reduces wastes and tracks material usage.

Manufacturing Overhead Costs

The final category of costs, manufacturing overhead (MOH), is also part of the full financial picture. These are costs that you can’t directly attribute to rubber products, but that affect the total cost of production. Examples include the salaries paid to maintenance personnel, manufacturing managers, materials management staff, and quality control personnel.

To determine your true costs, it’s important to consider the relationship between direct labor, direct materials, and MOH. For example, if you’re cutting gaskets in-house, your labor rates need to account for the salaries of quality control personnel who check the finished gaskets. If you’re ordering extra sheets because of waste, then your purchasing, receiving, and warehousing costs are also higher.

True Costs and the Business Case for Custom Fabrication

Now that you understand the components of your true costs, it’s time to learn more about the business case for custom fabrication. To get started, download Elasto Proxy’s Make or Buy It? white paper. We also invite you to contact us to learn more about how custom fabrication can save you time and money.

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Abrasive Water Jet Cutting vs. Guillotine Cutting for 45° Cuts on Bulb Trim Seals

Posted April 09, 2018 4:55 PM by Doug Sharpe

Abrasive water jet cutting and guillotine cutting can both produce 45° cuts on bulb trim seals, industrial rubber products that may contain metal wires. Abrasive water jet cutting uses a high-velocity, high-pressure stream of water and abrasive to cut through rubber, metal, and many other materials. Guillotine cutting uses a miter saw or metal blade instead. Like abrasive water jet cutting, guillotine cutting can cut through rubber profiles that contain metal reinforcements.

For buyers of bulb trim seals, choosing the right cutting method involves a comparison of manufacturing costs. Compared to guillotine cutting, abrasive water jet cutting has higher hourly rates. Yet abrasive water jet cutting can also produce higher volumes of better quality cuts in less time. Cutting a 45° angle is challenging, even for an experienced guillotine operator. If the employee cuts too quickly, the wires won’t cut cleanly. This requires surface finishing, which adds labor costs and extends cycle times.

As this article explains, abrasive water jet cutting can cost less than guillotine cutting for 45° cuts on bulb trim seals. Let’s look at an example to understand why this is the case.

Abrasive Water Jet Cutting vs. Guillotine Cutting Example

A mobile equipment manufacturer needs 30 bulb trim seals. Each rubber profile contains segmented steel cores and requires a 45° cut. A gasket fabricator presents two options for cutting.

Option A is an abrasive water jet cutter that uses an industrial robot for automated operations. The rate is $100/hour and the robot can cut 1 part every 2 minutes for 30 parts per hour. The mobile equipment manufacturer says that the rate seems expensive. The gasket fabricator explains that it includes the cost of the abrasive, water, operator, and the equipment itself. The cutting is especially fast, the fabricator adds, and the abrasive-water mixture makes cleaner cuts.

Option B is a semi-automatic guillotine cutter. The rate is $25/hour and the operator can cut 1 part every 10 minutes for 6 parts per hour. The lower rate may seem attractive, the fabricator says, but there’s more to cutting than slicing through the profile. For each cut, the operator must carefully align the material with the miter saw. The operator must cut slowly to avoid deforming the profile and then surface finish any metal wires with jagged edges. Surface finishing, the fabricator explains, can add significant costs.

For both cutting methods, the material usage and corresponding material costs are about the same. If the hourly rate for Option A is higher than Option B, why would the mobile equipment manufacturer choose abrasive water jet cutting? Where’s the cost savings?

Let’s review the numbers.

Option A, the abrasive water jet cutter, can cut 1 part every 2 minutes for 30 parts per hour at $100/hr. In other words, Option A can cut all the gaskets that are needed for $100.

Option B, the guillotine cutter, can cut 1 part every 10 minutes for 6 parts per hour at a rate of $25/hr. To cut 30 gaskets then, Option B requires 5 hours for a total of $125.

As you can see, Option A ($100) is less expensive than Option B ($125). There may be additional savings, too. Because abrasive water jet cutting makes cleaner cuts, subsequent operations such as splicing can take less time. For the mobile equipment manufacturer, abrasive water jet cutting is the right choice.

Watch the Video and Ask Elasto Proxy

Do you have questions about abrasive water jet cutting? Do you need bulb trim seals with steel segmented cores and 45° cuts? Then watch this video to see Elasto Proxy’s abrasive water jet cutter in action. Then, when you’re ready to discuss your application, contact us.

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Gasket Compression in Metal Housings and Assemblies

Posted April 03, 2018 10:15 AM by Doug Sharpe

Gasket compression in metal housings and assemblies can support sealing or contribute to gasket failure. That’s because rubber gaskets are resilient, but only to a point. Compressing a gasket within allowable limits forms a reliable seal. When a gasket is over-compressed, however, the rubber won’t rebound when the compressive stresses are removed. This creates a gap between the gasket and the surface of the housing or assembly. Gaps cause leaks, and seals that leak won’t support your designs.

Material scientists calls the permanent deformation of the gasket material “compression set”, a term that’s used widely but not always fully understood. Engineers need to know the basics of compression set, but they also need to consider its limitations as a test method. With housings and assemblies, it’s essential to account for the entire application environment, including variables such as temperature and vibration. Relaxation, a related phenomenon, is also associated with gasket compression.

Gasket Compression Set Basics

ASTM D395 is a standard from ASTM International that defines three different test methods (A, B, and C) for compression set in rubber materials. Typically, Test Method B is used. Unlike the other test methods, ASTM D395 B defines compression set as a percentage of the original deflection – the degree to which a sample of the gasket material is displaced under load.

ASTM D395 B testing begins by measuring the original thickness of a specimen. The sample is then put in a compressive device and compressed to 25% of its original height. Next, the device and the sample are put in an oven for either 22 or 70 hours (depending on the type of elastomer). The sample is then removed and allowed to cool for 30 minutes before its final thickness is measured.

For gasket designers, it’s important to note that ASTM D395 B accounts for compression at elevated temperatures. Yet it’s also important to understand that this testing is limited to an environment with constant compressive stress. That’s fine if you need a static seal, but what is you need a dynamic seal instead? Dynamic stressing also produces compression set, but there are some additional considerations.

Over-Compression Challenges

In metal housings and assemblies, over-compression can happen when a gasket is installed between metal parts that are held together by fasteners. If an operator over-torques the bolts or screws, the gasket may deform permanently. In other words, the rubber reaches compression set. When the bolts or screws loosen, gaps will form between the metal parts and the gasket material.

Applications with temperature changes and vibrations are especially susceptible to the loosening of fasteners. For example, mobile equipment and genset enclosures may be subjected to hot and cold temperatures that cause metal to expand and contract. They’re also exposed to vibrations from diesel engines. Under these dynamic conditions, even fasteners that are torqued properly may loosen.

Material relaxation poses gasket-related challenges, too. With a housing or assembly gasket, a rubber that’s compressed will “push back” against the metal parts and fill the tiny gaps that would otherwise exist between the metal surfaces. Within an hour of the gasket’s installation, however, this reciprocating force may be only 75% of the original force. Seal failure many not happen, but leakage can occur.

Compression-related problems aren’t limited to flat gaskets with fasteners either. Rubber profiles that attach to metal surfaces with tape or adhesives are also subject to over-compression. Examples include hatch seals on military vehicles and the dishwasher seals on appliances. With the latter example, the use of hot water and detergents can affect a gasket’s material properties and degrade its performance.

Compression Set Solutions

Do you need to replace rubber gaskets where compression set has occurred? Do you need help choosing a gasket material that will form a reliable seal and avoid over-compression? Elasto Proxy is an experienced gasket fabricator and creative problem-solver. To find the right sealing solution, contact us.

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