by Brandon Pascual Brandon Pascual No Comments

The Ultimate Guide to PTFE Sheets: Unleashing the Power of the Most Versatile Material on the Planet

Hey there, innovators! Are you ready to unlock the secrets of the most incredible material in the universe? Look no further than PTFE sheets!

Imagine a material that’s like a superhero cape – it’s non-stick, chemical-resistant, and can withstand temperatures that would melt lesser materials like a popsicle on a hot summer day. Sounds like science fiction, right? But trust us, PTFE sheets are the real deal.

THE EVOLUTION OF PTFE UNRAVELING THE HISTORY AND ADVANCEMENTS IN PTFE FIBER AND POLYMER

What are PTFE Sheets?

PTFE (Polytetrafluoroethylene) sheets are made from a unique polymer that’s like a molecular ninja – it can dodge and weave around chemicals, heat, and even radiation like a pro. This means that PTFE sheets can be used in some of the most extreme environments on the planet, from the depths of space to the heart of a nuclear reactor.

Properties of PTFE Sheets:

Rotary Shaft Seals for Oil and Gas Industry | Advanced EMC Technologies

Chemical Resistance: PTFE can withstand almost all chemicals.

High Temperature Tolerance: It remains stable from -200°C to +260°C.

Non-stick Surface: Few substances will permanently adhere to a PTFE coating.

Low Friction: PTFE has one of the lowest coefficients of friction of any solid.

Semiconductor circuit board

High Dielectric Strength: Excellent insulator for electrical components.

Non-Flammable: It is used in high-temperature environments without risk of fire.

Spring Energized PTFE Seals

Applications of PTFE Sheets

The possibilities are endless! With PTFE sheets, you can create:

Gaskets and Seals: Ideal for applications that require resistance to aggressive chemicals and high temperatures.

Bearings and Bushings: Provides a frictionless surface to reduce wear and tear.

Liners and Coatings: Protects equipment from corrosion and contamination.

Insulators and Dielectrics: Used in electrical applications due to its high dielectric strength.

Spring Energized Teflon Seals

Medical Devices: Biocompatible and used in various surgical instruments and implants.

Aerospace Components: Withstands the extreme conditions of space.

Food Processing Equipment: Non-stick and easy to clean, perfect for hygienic applications.

Energy Storage Systems: Durable and stable, ideal for use in batteries and fuel cells.

THE EVOLUTION OF PTFE: UNRAVELING THE HISTORY AND ADVANCEMENTS IN PTFE FIBER AND POLYMER

Real-World Applications of PTFE Sheets

PTFE sheets are used in a wide range of industries, from aerospace to medical devices. Here are some real-world examples of how PTFE sheets are being used:

Aerospace: PTFE sheets are used in the manufacture of aircraft and spacecraft components, such as seals, gaskets, and bearings. Their ability to withstand extreme temperatures and chemical exposure makes them ideal for these applications.

Medical Devices: PTFE sheets are used in the production of medical devices, such as implantable devices, surgical instruments, and diagnostic equipment. Their biocompatibility and non-stick properties make them suitable for a wide range of medical applications.

Spring Energized Teflon Seals

Food Processing: PTFE sheets are used in the production of food processing equipment, such as conveyor belts, seals, and gaskets. Their non-stick and chemical-resistant properties ensure hygiene and durability.

Energy Storage: PTFE sheets are used in the production of energy storage systems, such as batteries and fuel cells. Their thermal stability and chemical resistance enhance the efficiency and longevity of these systems.

EXPANDED PTFE VS. PTFE

Case Study: PTFE Sheets in Aerospace Applications

Background: A leading aerospace manufacturer was facing challenges with traditional sealing materials in their jet engines. The extreme temperatures and aggressive chemicals were causing frequent failures and maintenance issues.

Solution: The manufacturer switched to PTFE sheets for gaskets and seals. PTFE’s high thermal stability and chemical resistance provided a durable solution that could withstand the harsh operating conditions.

Results:

  • Increased Reliability: The use of PTFE sheets significantly reduced the frequency of seal failures.
  • Cost Savings: Maintenance costs dropped due to the longer lifespan of PTFE seals.
  • Performance Improvement: The overall performance and efficiency of the jet engines improved, leading to higher customer satisfaction.

UNDERSTANDING THE DIFFERENT TYPES OF COMPOSITE BUSHINGS IN TECHNOLOGY

So…

So, what are you waiting for? With PTFE sheets, the possibilities are endless. Whether you’re a seasoned engineer or just starting out, we invite you to join the PTFE revolution!

PTFE sheets are incredibly versatile, offering unmatched chemical resistance, thermal stability, and non-stick properties. They are essential in various industries, from aerospace to medical devices, providing reliable and long-lasting solutions.

Ready to explore the incredible benefits and applications of PTFE sheets? Click here to get started or contact us at Advanced EMC Technologies today!

Contact Us Today!

PTFE SHEET FLASH SALE!

Available Sizes and Pricing

Our PTFE sheets are available in a variety of thicknesses to meet your specific needs:

1/32″ Thickness

Price Per Sheet: $25.00

Weight Per Sheet: 6 lbs

1/16″ Thickness

Price Per Sheet: $50.00

Weight Per Sheet: 12 lbs

3/32″ Thickness

Price Per Sheet: $77.00

Weight Per Sheet: 18 lbs

1/8″ Thickness

Price Per Sheet: $100.00

Weight Per Sheet: 24 lbs

3/16″ Thickness

Price Per Sheet: $110.00

Weight Per Sheet: 35 lbs

Technical Data on PTFE Sheets

Polytetrafluoroethylene (PTFE)

Thickness Range: 0.79375 mm to 4.7625 mm

Sheet Sizes: 1219.2 mm x 1219.2 mm

Density: 2.2 g/cm³

Tensile Strength: 20-30 MPa

Elongation at Break: 300-500%

Hardness: Shore D 50-65

Temperature Range: -200°C to +260°C

Thermal Conductivity: 0.25 W/mK

Dielectric Strength: 60-80 kV/mm

Chemical Resistance: Excellent resistance to most chemicals, including acids, bases, and solvents

Water Absorption: <0.01%

Flammability: UL 94 V-0

Benefits of Our PTFE Sheets

Chemical Resistance: Withstand aggressive chemicals.

Thermal Stability: Maintain properties in extreme temperatures.

Non-stick Surface: Easy cleaning and maintenance.

Low Friction: Reduce wear and extend the life of mechanical parts.

High Dielectric Strength: Ideal for electrical applications.

Non-Flammable: Safe for high-temperature environments.

Contact Us Today!

Additional Resources

Contact Information:

by Brandon Pascual Brandon Pascual No Comments

Advanced EMC Technologies: Revolutionizing Sealing Solutions Across Industries

Advanced EMC Technologies is synonymous with innovation and excellence in PTFE sealing solutions. Our products are designed to meet the most demanding requirements across various industries. In this blog, we delve into real-world application examples to showcase the exceptional capabilities of our PTFE rotary shaft seals in diverse fields such as oil and gas, renewable energy, aerospace, and space exploration.

Real-World Application: PTFE Rotary Shaft Seals in Oil and Gas Drilling

Challenge: In the oil and gas industry, drilling operations face extreme conditions, including high pressures, temperatures, and exposure to harsh chemicals and abrasive materials. Traditional seals often fail under these conditions, leading to costly downtime and repairs.

Solution: Advanced EMC Technologies’ PTFE rotary shaft seals provide a reliable solution for these challenging environments. Let’s explore how our seals excel in this application:

High-Pressure Resistance: During drilling operations, equipment such as mud pumps and rotary steerable systems experience high pressures. Our PTFE seals can withstand pressures up to 15 bar, ensuring continuous operation without seal failure.

TYPES OF SEALS FOR OIL AND GAS INDUSTRY

Broad Temperature Range: The temperature range in drilling operations can vary significantly, from sub-zero temperatures in deep-sea environments to high temperatures encountered during drilling. Our seals operate efficiently from -40 to +220°C, providing unmatched reliability.

THE BENEFITS OF PTFE SPRING ENERGIZED SEALS FOR OIL AND GAS

Chemical Resistance: Drilling fluids and chemicals used in oil and gas operations can be highly corrosive. Our PTFE seals offer exceptional resistance to a wide range of chemicals, preventing degradation and ensuring long-lasting performance.

HOW TO DESIGN AND SELECT SEALS FOR OIL AND GAS

Minimal Friction and Wear: Equipment downtime due to seal failure can be costly. Our PTFE rotary shaft seals are designed with a durable sealing lip that exhibits minimal friction and wear, reducing maintenance frequency and extending the life of the equipment.

THE OIL AND GAS INDUSTRY DURING COVID-19

Impact: By using our PTFE rotary shaft seals, oil and gas companies can achieve higher operational efficiency. The seals’ ability to withstand extreme conditions reduces the risk of equipment failure, ensuring continuous drilling operations and translating into significant cost savings.

Enhancing Energy Efficiency: PTFE Seals in Renewable Energy

Challenge: The renewable energy sector, including wind and solar power, demands reliable sealing solutions that can withstand environmental extremes and ensure efficient operation. Components must handle wide temperature ranges, exposure to elements, and continuous motion.

Solution: Advanced EMC Technologies’ PTFE seals are ideal for renewable energy applications. Here’s how:

Weather Resistance: Our seals provide excellent resistance to UV exposure, moisture, and extreme temperatures, making them perfect for outdoor applications such as wind turbine blades and solar panel mounts.

BENEFITS OF SPRING-ENERGIZED SEALS FOR WIND TURBINES

Durability: The high wear resistance of our PTFE seals ensures longevity, reducing the need for frequent maintenance and replacements in renewable energy installations.

WHEN TO USE A PTFE ROTARY SHAFT SEAL

Efficiency: By minimizing friction and wear, our seals contribute to the overall efficiency of energy generation systems, ensuring optimal performance and reduced energy loss.

SPRING-ENERGIZED SEALS FOR THE WIND INDUSTRY

Impact: Wind turbines and solar panels equipped with our PTFE seals perform more efficiently and require less maintenance, leading to lower operational costs and more sustainable energy production.

Taking Flight: PTFE Seals in Aerospace

Challenge: Aerospace applications demand sealing solutions that can endure high altitudes, temperature fluctuations, and extreme pressure conditions. Aircraft components require seals that guarantee safety and reliability.

Solution: Advanced EMC Technologies’ PTFE seals are designed to meet these stringent requirements. Here’s why our seals are a top choice for aerospace:

Temperature Tolerance: Our seals perform effectively across a broad temperature range, from the cold of high altitudes to the heat generated by aircraft engines.

A COMPREHENSIVE GUIDE TO AEROSPACE SEALS

Pressure Resistance: The high-pressure resistance of our PTFE seals ensures reliability in hydraulic systems, fuel systems, and other critical components.

SPRING-ENERGIZED SEALS FOR SPACEFLIGHT

Lightweight: Weight is a critical factor in aerospace applications. Our PTFE seals are lightweight yet robust, contributing to overall aircraft efficiency without compromising on performance.

PTFE AEROSPACE SEALS

Impact: Our seals ensure that aircraft components operate smoothly and safely, reducing the risk of mechanical failures and enhancing the overall reliability and efficiency of aerospace systems.

Reaching for the Stars: PTFE Seals in Space Exploration

Challenge: Space missions involve extreme conditions, including vacuum, radiation, and cryogenic temperatures. Seals used in rockets and spacecraft must offer exceptional reliability and durability to ensure mission success.

Solution: Advanced EMC Technologies’ PTFE seals are perfect for space applications. Here’s how they make a difference:

Cryogenic Performance: Our seals maintain integrity at cryogenic temperatures, crucial for handling rocket fuels like liquid oxygen (LOX) and liquid hydrogen.

SEALS IN SPACE: THE UNSUNG HEROES OF ROCKETRY

Vacuum Compatibility: PTFE’s properties make our seals ideal for use in the vacuum of space, where traditional materials might fail.

A COMPREHENSIVE GUIDE TO AEROSPACE SEALS

Chemical Inertness: The chemical resistance of our PTFE seals ensures they can withstand exposure to various rocket propellants and other harsh substances used in space missions.

ADVANCEMENTS IN AEROSPACE DYNAMIC SEALS: ENHANCING HIGH-TEMPERATURE CAPABILITIES FOR AEROSPACE APPLICATIONS

Impact: Our seals play a vital role in the success of space missions by ensuring the reliability and safety of critical components, from rocket engines to spacecraft systems.

Why Choose Advanced EMC Technologies?

  1. Customization: We understand that each application has unique requirements. Our team works closely with clients to design and manufacture customized PTFE seals that meet specific operational needs.
  2. Quality Assurance: Our seals are manufactured to the highest standards, ensuring consistent quality and performance. We utilize advanced materials and manufacturing processes to deliver superior products.
  3. Expert Support: From initial consultation to after-sales support, our team of experts is dedicated to providing exceptional service. We assist clients in selecting the right seals and offer ongoing support to ensure optimal performance.

Advanced EMC Technologies‘ PTFE rotary shaft seals are transforming industries by providing reliable, high-performance sealing solutions. Our seals are engineered to excel in the most challenging environments, ensuring operational efficiency, cost savings, and environmental safety.

Whether it’s drilling deep in the earth, harnessing the power of the wind and sun, soaring through the skies, or exploring the final frontier, Advanced EMC Technologies has the sealing solutions to keep your operations running smoothly.

For more information about our products and services, visit our website or contact our sales team at Sales@advanced-emc.com. Let Advanced EMC Technologies be your trusted partner in sealing solutions for all your industrial needs.

by admin admin No Comments

Spring-Energized Seals for Spaceflight

With the success of commercial spaceflight companies such as SpaceX, Blue Origin, and Virgin Galactic, there is an increasing demand for high performance, dependable seals. Rockets are one of the areas where harsh environment seals are needed, but also pose extremely challenging issues for success. Spring energized seals are one solution, but why?

What Makes a Modern Rocket

Successful spaceflight involves rockets, and the primary sections of a modern two-stage rocket are the first stage engine bay, first stage, second stage engine bay, second stage, and, last of all, the payload. This constitutes the most common configuration for today’s NewSpace companies. 

Such a configuration features an expendable or reusable first stage that contains 4 to 9 engines (the number of engines varies based on company design) and an expendable second stage that typically contains a single vacuum-optimized engine. The goal of the first and second stages is to produce enough thrust to achieve a targeted orbital velocity–usually around 17,500 mph– for the payload that sits on top of the rocket.

Propellants and Pressurants

Most rockets use either solid or liquid propellant. In this blog post, the focus will be on bi-propellant rockets, which are most commonly being used or developed in the United States commercial market. Bi-propellant rockets, as the name implies, use a combination of propellants. Common propellant configurations include:

  • RP-1 (Highly refined kerosene)/Liquid Oxygen (LOX) (aka, Kero-Lox)
  • Liquid Methane/LOX (aka, Metha-Lox or Lox-meth)
  • Liquid Hydrogen/LOX (Hydro-Lox)

Pressurants and support fluids include:

  • GN2 (Gaseous Nitrogen)
  • Helium (He)
  • GOX (Gaseous Oxygen)
  • GCH4 (Gaseous Methane)

How Modern Rocket Propulsion Systems Work

For a pump-fed system, the propellants are fed from low pressure tanks into a turbopump assembly (TPA). This significantly raises the pressures to be injected into the main combustion chamber (MCC). In most cases, a small portion of the propellants are scavenged from the high-pressure side to feed a separate small combustion chamber known as a gas-generator or pre-burner and used to drive the turbine. These fuel or oxygen rich gases can then either be vented to the atmosphere or re-injected into the MCC.

Operating Conditions of a Rocket Propulsion System

Consideration of the operating conditions within a rocket propulsion system provides insight into the challenges faced by the seals.

  • State 1 – Tank to Turbopump Assembly (TPA) inlet: propellants (oxygen + methane) are usually around 50 -150 psi and RP1 will be between 20 F and 80 F while the cryogenics will be between -450 F to -260 F.
  • State 2 – TPA outlet: depending on the engine, pumps will raise these pressures to somewhere between 1,500 and 16,000 PSI.
  • State 3 – Pre-burner: pressure will have dropped across the lines and injector – usually 8-15%, however temperatures will be between 800 -1,500 F.
  • State 4: depending on the engine cycle, propellants may be in a liquid-liquid state, gas-liquid state, or gas-gas state at an array of temperatures and pressures before mixing in the MC; note that in most cases the fluids will be supercritical.
  • State 5: once across the injector, the remaining propellants will combust at temperatures higher than 4000 F while pressure in the MCC may be between 50-20% of State 2 depending on system losses; note that this pressure drops quickly as the gases are pushed toward the atmosphere.

Depending upon which stage is involved, seal requirements vary greatly but high pressures and extreme temperatures will always be involved. 

Rocket Engine Seals

Rocket engine seals must perform in some of the most harsh environments imaginable and may involve wide operating temperature ranges (including cryogenic), extreme pressures, wide thermal cycling, and chemical compatibility with fuels, propellants, and pressurants. Most importantly, they must be extremely reliable. As an example, consider the just a rocket turbopump.

The image shown is a Hydro-Lox turbopump with a geared coupling used in the Aerojet Rocketdyne RL10 engine. Where it is labeled with a 1 indicates flange locations that likely use spring-energized face seals. Downstream of the outlets  will be the main valves, and they too will most likely have additional flange connections that will require seals. Areas labeled with 2 indicate other flange locations that depend on face seals of unknown makeup but likely involve hot gas connections.

Spring Energized Seals: A Rocket Sealing Solution

One of the most reliable, harsh environment sealing solutions is the spring energized seal. Unlike conventional seals, a spring energized seal includes an energizer that enables the seal lip to stay in contact with the mating surface through extreme variations in pressure and temperature,and  dimensional changes, as well as out of roundness, eccentricity, hardware misalignment, and some degree of wear. Vibration, cryogenic temperatures, and high temperatures are also an area where spring-energized seals offer outstanding performance.

They are highly durable in operating environments where other seals simply cannot survive. In fact, the performance of such seals has been well established in aviation and aerospace, including both NASA and commercial rockets. 

A wide variety of jacket materials are available, with some of the most widely used aerospace options being PTFE (trade name Teflon) and Hytrel. Materials such as Teflon and Hytrel can handle extreme temperatures, are chemically compatible with media involved, are heat resilient, provide low friction, have excellent wear characteristics, and are typically self lubricating. In addition, both materials are available in grades that provide key characteristics such as improved wear, lower friction, additional stiffness, better strength, etc.

And the same is true for spring energizers, which vary in both geometry and material used. For example, vacuum pressure and cryogenic applications often utilize V-springs (also known as V ribbon springs), high pressure environments may use coil springs, and vacuum pressure operating conditions with medium speeds may utilize helical springs. Various materials can be used for the spring, which will be enclosed within the seal jacket; because of this, the spring material will be protected from whatever media is being sealed.

Conclusion

If you are in need of spring energized seals for space applications, allow the seal specialists at Advanced EMC help you. We have a long history of providing our customers with the seals they need, including custom engineered and manufactured solutions that not only meet their specifications but also the rigorous standards that may be involved. Advanced EMC has the design, manufacturing, and testing capabilities you need to make your design a success. Contact us today to learn more.

Benefits of PTFE for Sealing Applications
by Jackie Johnson Jackie Johnson No Comments

Benefits of PTFE For Sealing Applications

PTFE (Polytetrafluoroethylene), also known by its trade name Teflon, is a polymer material commonly used in sealing applications that offers unparalleled stability and sealing characteristics across an extremely wide range of temperatures, from the extreme heat of a space shuttle engine to the cryogenically cold temperatures used to preserve

In this article, we will discuss how and why PTFE is one of the best materials to use for seals in a wide variety of applications.

Low Friction

PTFE has the highest melting point and lowest friction, and is the most inert of all the fluoropolymers. It has a continuous service temperature rating of 500 degrees Fahrenheit. Molding powders are excellent, fine cut granular resins, well suited for a variety of demanding chemical, mechanical, electrical and non-stick surface applications.

Such applications include:

  • Cookware
  • Outdoor Rain Gear
  • Medical Devices
  • And more!

Cryogenic Applications

Cryogenic seals are used with super-cooled media, like liquid hydrogen or compressed natural gas, at temperatures below -238°F and down to -460°F (absolute zero). Cold temperatures like this are rough on a seal because at these temperatures most materials begin to exhibit highly brittle behavior and lubricants typically cannot be used because they will freeze. PTFE seals, however, can handle temperatures all the way down to -450°F and are capable of dry running because of their extremely low friction. PTFE cryogenic seals are used in industries like oil & gas, pharmaceuticals, and aerospace.

High Temperature Applications

PTFE seals work well at the other end of the spectrum, too. They can continue to function in extreme temperatures up to 600°F, and continuous operating temperatures up to 600°F. Note that a filler may be required to enable the PTFE to dissipate heat more quickly. It’s not uncommon to see PTFE seals in petroleum or steam applications where temperatures greatly exceed 200°F.

PTFE is also non-flammable, making it ideal for use in applications such as jet propulsion engines. Where other materials would simply melt under the pressure of constant exposure to high temperature flames, PTFE is built to withstand even the hottest of environments.

The use of seals for high temperature applications include oil and gas industry and aerospace, to name a few.

Chemical Applications

The chemical resistance of PTFE is some of the best on the market. It is stable in most aggressive and corrosive media, including:

  • Acetone
  • Chloroform
  • Citric Acid
  • Hydrochloric Acid
  • Sulfuric Acid
  • Tallow
  • Sodium Peroxide
  • And more!

However, it should be pointed that that PTFE is not chemically resistive to liquid or dissolved alkali metals, fluorines and other extremely potent oxidizers, as well as fluorine gas and similar compounds. Outside of those, PTFE is an excellent choice for applications involving chemicals.

Oil and Gas Industry

Seals are critical for the safe and reliable operation of oil rigs across the globe. Not only do seals need to be able to withstand a wide variety of extreme temperatures, but they need to be able to handle extreme pressures as well. For well drilling, for example, seals need to handle pressures from 345 to 2070 bar (5000 to 30000 psi).

For those reasons, PTFE is an incredibly popular material to make oil and gas seals out of. Because of it’s resistance to heat, cold and high pressure, PTFE can withstand the rigors of oil and gas unlike any other material.

Spring-energized Seals

In order to retain sealing power under extreme temperatures, many engineers and designers go with spring-energized PTFE seals. The spring provides optimal sealing by forcing the lip of the seal against the mating surface and helps to account for dimensional changes as a result of temperature fluctuations.

A highly efficient seal is created as the system pressure increases enough to take over from the spring and engage the shaft or bore. The spring or energized seal assembly provides permanent resilience to the seal jacket and compensates for jacket wear, hardware misalignment and eccentricity. The jacket material is critical in design to assure proper seal performance.

Rotary Shaft Seals

Using PTFE in rotary shaft seals allows them to be able to run at higher pressures and velocities when compared to other materials. They are also able to have tighter sealing, often exceeding 35 BAR and can run at far more extreme temperatures ranging from -64 degrees Fahrenheit (-53 degrees Celsius) to 450 degrees Fahrenheit (232 degrees Celsius).

On top of that, they are:

  • Inert to most chemicals
  • Can withstand speeds up to 35 m/s
  • Compatible with most lubricants
  • Come in a wide range of sizes
  • And more!

Conclusion

PTFE is an ideal sealing material for both extremely high temperature applications and demanding cryogenic applications. It retains its key sealing properties: stiffness, strength, dimensional stability (may require spring energizer), low friction, and chemical compatibility- even in the most aggressive operating conditions.

Need PTFE sealing solutions? Advanced EMC Technologies is the leading provider of PTFE spring energized and rotary shaft seals in the US. Contact us today!

Rotary Shaft Seals for Automobiles | Advanced EMC Technologies
by Sara McCaslin, PhD Sara McCaslin, PhD No Comments

Rotary Shaft Seals for Automobiles

Even the simplest automobile requires a wide variety of seals, including rotary shaft seals. In this blog post, you will learn the basics of these seals within the context of the automotive industry, including the materials commonly used and why PTFE is so often recommended.

Rotary Shaft Seals

The goal of a rotary shaft seal is to prevent the leakage of oil, grease, and other fluids (e.g., transmission fluid, brake fluid, air conditioning refrigerant) while also keeping environmental contaminants out. These seals, sometimes called oil or grease seals, are used with bearings to keep lubricants within the bearing and environmental contamination out (i.e., lubrication retention). The term rotary refers to their ability to perform in the presence of both rotary and swiveling movements.

Where Rotary Shaft Seals Are Used in the Automotive Industry

Rotary shaft seals are a necessary part of many components and systems within cars, trucks, buses, high performance vehicles, and motorsports. And seals are needed for EVs (electric vehicles) and HEV (Hybrid Electric Vehicles) as well. These seals are also used with ATV (All Terrain Vehicles).  Some of the most common areas of application in automotive transportation are:

  • Air conditioning compressors
  • Braking systems
  • Pumps
  • Gearboxes
  • Power transmissions
  • Steering wheels

In most of these applications, the failure of a seal can lead to serious repercussions that include bodily injury, damage to the vehicle, and danger to those around the vehicle. Because of this, finding the right high quality seal for your application is extremely important.

Automotive Seal Operating Conditions

While the conditions for automotive rotary shaft seals do vary depending on their specific applications, the most common operating environments include …

  • Extreme temperatures
  • Environmental elements
  • Vibration and shock loadings
  • High contamination exposure
  • Chemical compatibility
  • Low friction
  • Wear resistance
  • Compliance with automotive standards

Environmental elements include exposure to sunlight, ozone, UV, and oxidation, all of which can accelerate the degradation of a seal. Contamination can include water, dirt, grease, and other debris, while the seals are likely to be exposed to materials such as diesel, hydraulic fluid, brake fluids, coolants, and chemical solvents. 

Materials Used in Rotary Shaft Seals

The basic components of a spring energized seal include a flexible inner seal lip that is bonded to a rigid outer component. In addition, some of these seals may include a spring energizer to keep the lip in contact with the sealing surface (note that spring-energized seals are most commonly used for oil retention as opposed to grease retention). Furthermore, some applications may require a seal with two lips where one serves as a wiper seal or dust lip to further prevent the ingression of contaminants.

The outer material for a rotary shaft seal is responsible for seal positioning and retention in the seal housing. This part of the seal is typically made from stainless steel, aluminum, or a rigid non-metallic composite material. 

The seal lip itself is made from either an elastomer or a polymer, with high performance PTFE being one of the most commonly used polymers. PTFE meets all the requirements for an effective, dependable seal lip, including the ability to handle high pressures, wide ranging chemical compatibility, extremely low friction, and excellent wear resistance. PTFE can also include additives such as carbon or MoS2 that can enhance properties such as strength, stiffness, wear resistance, and low friction.

Nitrile rubber (NBR, Buna-N) and polyacrylate rubber (ACM) are both widely used elastomeric materials for automotive rotary shaft seals. Another often used elastomer category is fluoroelastomers commonly referred to as FKM, Viton, and FPM. These offer superior performance compared to nitrile and polyacrylate, but they do cost more. 

PTFE Rotary Shaft Seals

At Advanced-EMC, we highly recommend the use of PTFE rotary shaft seals in the automotive industry where possible. They provide excellent performance in the harsh conditions often involved and are the most chemically compatible and low friction polymer on the market today. They can outperform elastomeric materials and are quickly replacing their use in many applications.

There are several grades of PTFE to choose from, including …

  • Virgin PTFE: light-duty service with slow speeds
  • 25% Glass-filled PTFE: wear and extrusion resistant but abrasive to shafts with a hardness less than 62C
  • 23% Carbon / 2% Graphite-filled PTFE: general purpose service where extrusion and deformation resistance are necessary
  • 15% Glass / 5% MoS2 filled PTFE: excellent wear resistance makes it well adapted to higher speed applications
  • Polyimide-filled PTFE: because of its low abrasion, works well with soft materials such as 300 SS and Aluminum
  • Modified PTFE: higher mechanical strength and better wear resistance

Conclusion

Rotary shaft seals can be found everywhere from the air conditioning to the power transmission system on a vehicle. Finding the right sealing solution that can handle the extremely harsh operating conditions and high temperature environments can be challenging, but PTFE has become one of the most popular choices for the seal lip material. 

If you are interested in an effective, reliable sealing solution for your automotive application, contact the knowledgeable team at Advanced-EMC today. Our engineers can work with you to find the right seal, made from the right materials, for even your most challenging designs.

 

by Sara McCaslin, PhD Sara McCaslin, PhD No Comments

Spring-Energized Seals for the Wind Industry

Spring-Energized Seals for the Wind Industry

There is little doubt that global interest in renewable energy sources remains high, and that includes wind-based energy sources. According to the World Wind Energy Association (WWEA), the overall capacity of wind turbines installed worldwide reached 650.8 gigawatts in 2019, representing a 10.1% increase from 2018. However, for increased growth in the wind industry, the design of wind turbines must become even more efficient and reliable — and wind turbine seals are one area where there is potential for improvement.

Wind Turbine Seals

Among over 5,000 components in a typical wind turbine, there are six places where you will always find seals:

  • Main bearing
  • Main gear
  • Pitch cylinder
  • Lock cylinder
  • Main and yaw brakes
  • Hydraulic accumulator

Another way of looking at wind turbine seals is by their location:

  • Rotor
  • Blades
  • Tower
  • Alternator
  • Gear Box

The importance of reliable seals in the wind industry cannot be overstated. They enhance the performance and efficiency of the wind turbines, extend their useful life, and minimize the costs and downtime associated with maintenance. Investing in the right type of seals for wind applications are critical, and traditional seals may not offer the sealing power and expected life that is needed.

Sealing Challenges in the Wind Industry

There are a host of challenges faced by engineers selecting seals for wind turbine applications beyond just vibration and high stresses caused by wind gusts and rotor speed variations. Because they are outdoors year-round, wind turbines are constantly exposed to UV and ozone which can cause seals to degrade more rapidly than normal. Then there are the extreme operating temperatures, from an icy  -40°F in Arctic regions to 140°F as a maximum standard operating temperature which can make it challenging to find a seal material that can maintain reliable performance. 

Then there are issues with abrasive substances such as sand, grit, and salt from seawater that can cause the lip of the seal to wear away. Then there are the inevitable changes in pressure that come from normal weather variations. The use of polymeric spring-energized seals, however, can address many of these challenges.

Spring-Energized Seals

In a spring-energized seal, a metal spring is used to maintain the seal lip in place to achieve a far more reliable seal for both keeping contaminants out and critical lubricants within. Spring-energized seals can maintain contact even in the presence of misalignments and uneven mating surfaces, dimensional changes resulting from temperature fluctuations or water absorption, premature wear from contact with abrasive substances, and vibration.

Various geometric configurations for the spring element are available, including coil, canted coil, helical, and cantilever springs. Each of these spring types has conditions for which they work best (e.g., cantilever springs work very well for static sealing). When the right spring geometry is coupled with an appropriate polymer, the result is a durable, rugged, reliable seal.

Arkansas Spring Energized Seal Company

Conclusion

One of the key aspects of wind turbine design involves selecting the right kind of seals — seals that will maintain consistent, secure contact even in the harshest of operating conditions. Spring-energized seals are an excellent way to contribute to efficient performance, reliability, and reduced maintenance requirements for modern wind turbines.

by admin admin No Comments

Fluid Media and PTFE Spring-Energized Seal Performance

FLUID MEDIA AND PTFE SEALS:

You may not be aware of the fact that the fluid media has a significant effect on seal wear.  In this article, we are going to explore exactly how fluid media can affect the performance of your PTFE spring-energized seal.

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Need additional education? Check out these “Popular PTFE Post”  from Advanced EMC Technologies:

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