Gaskets are mechanical seals used to fill in the spaces between two mated surfaces. They are engineered to prevent fluids (gas or liquid) from leaking out of or into the system between the two surfaces while under compression. In some assemblies, they serve as a barrier that keeps two components separated to protect them against friction damage.
These sealing devices can be made from a wide range of materials depending on the requirements and restrictions of the application. One of the most commonly used is silicone rubber. It exhibits many advantageous characteristics that make it suitable for various industrial and commercial applications. For example, its excellent resistance to extreme temperatures, ozone, and ultraviolet (UV) radiation enables it to be used in outdoor environments without fear of premature degradation.
Types of Silicone Gasket Materials
Silicone rubber comes in many types, grades, and forms to suit different applications. The ones commonly used to make gaskets are:
Solid silicone rubber. This material has a dense molecular structure. It can have low or high durometers. The former is suitable for seals with low closure force requirements, while the latter is suitable for seals with high closure force requirements.
Sponge silicone rubber. This material has a cellular structure that provides some cushioning and padding properties. It is available in two basic types: open-cell and closed-cell. Open-cell sponge silicone has interconnected pockets that allow air, chemicals, and water to pass through when it is uncompressed. Closed-cell sponge silicone has pockets that are filled with nitrogen to prevent anything from passing through it.
Foam silicone rubber. This material offers flame resistance. It is available in soft, medium, firm, and extra-firm grades and open-cell, closed-cell, and combined open-cell/closed-cell variations.
Liquid silicone rubber (LSR). This material is a two-part material system that must be mixed and heat cured before use. It offers fast and inexpensive molding operations, clean curing operations, and low durometer options.
These silicone rubber gasket materials can be made in various grades, such as FDA-compliant, UL-compliant, and MIL-SPEC, and shaped into sheet, roll, and other standard or custom profile forms to meet different industry and application requirements.
Why Use Silicone Rubber?
Silicone rubber exhibits many properties that make it ideal for use in gaskets, such as:
Resilience over a broad temperature range. Silicone rubber is resistant to chemicals, moisture, oxygen, ozone, and sunlight, and it maintains these qualities in both extremely low and extremely high temperatures.
Resistance to permanent compression set. Silicone rubber will return to its original shape after being subjected to compressive forces.
Availability in various durometers, colors, and specialty grades. Silicone rubber comes in numerous hardness levels, colors, and grades, so it can be used for many applications.
Common Applications of Silicone Rubber Gaskets
Some of the industries that commonly rely on silicone rubber gaskets include:
Contact Us for Silicone Gasket Solutions
Want additional information on silicone rubber gaskets? Ask the experts at Mercer Gasket & Shim! We’ve supplied gaskets and other industrial products for over 100 years. We have what it takes to answer or address any questions or concerns you may have about these products.
If you need standard or custom gaskets, we’ve got you covered. Our extensive selection of gasket materials enables you to choose the best material for your application. Additionally, as an ISO 9001:2015 company, you can depend on us for quality products and services. Our standard is 100% defect-free products delivered 100% on time.
Comments Off on Gasket vs. O-Ring: Differences and Common Applications
While gaskets and O-rings serve a similar purpose of sealing out air or liquid, the two are designed for different situations and vary in appearance. Here, the team at Mercer Gasket & Shim will explain the differences between these sealing solutions to help you determine the best one for your application.
What Are Gaskets and O-Rings?
Gaskets are flat pieces of material used to make a seal between two flat surfaces, usually with a bolted joint. O-rings are round, ring-shaped pieces that must set in a groove to create a seal between two parts. While gaskets are most commonly circles, they are also manufactured in a variety of other shapes. Both gaskets and O-rings are made using flexible materials, but gaskets can also be made out of other rigid polymers and metals. The thickness of an O-ring can be customized to fit unique specifications, while gaskets may be layered with different coatings to work best for various applications.
Common Applications for Gaskets
Electrical motors, power generators, and transformers
Handheld communication devices
Aerospace and defense industry
Transportation and automotive
Food and beverage industry
Common Applications for O-Rings
Equipment with fluid seal points
HVAC – Heating, Ventilation, and Air Conditioning
Pharmaceutical and medical industry
Pulp and paper industry
Choosing the Best for Your Application
When deciding whether a gasket or O-ring is best for your application, consider the environment and function of the seal. When choosing the best seal, look for features such as shape, temperature, and pressure.
When a non-circular joint requires a good seal, an O-ring would be difficult to use because of its round shape. Gaskets can be customized to almost any shape, allowing them to work as a seal for a larger variety of applications.
The operating temperature of equipment will determine the best material to use for manufacturing the O-ring or gasket. While both can withstand a wide range of temperatures, gaskets are best for extreme temperature situations. However, O-rings perform better than gaskets in applications with extreme pressure.
Contact Us for Your Gaskets and O-Rings Needs
Mercer Gasket & Shim is a premium manufacturer of custom O-rings and gaskets in an array of materials and sizes to best suit our customers’ needs. Our team has over 80 years of experience in sealing solutions. We are committed to the highest standards with a target for 100% on-time delivery and a 0% defect rate, and strive to provide the fastest turnaround in the industry. To learn more about our cost-effective, durable sealing solutions contact us or request a quote today.
Comments Off on 6 Tips for Choosing the Right Gasket
Everything from the size of the gasket to its ability to withstand degradation and damage plays a role in how well it can stop the escape of air, gas, water, or other fluids. Gaskets are placed between two flush surfaces that have a channel for fluid movement. Because the two surfaces might not be perfectly flush or straight, they’re going to have gaps that fluid can move through. Gaskets correct those gaps by being compressed between the two surfaces to effectively eliminate any leakage pathway.
Key Gasket Selection Factors — Gasket Materials, Types, and Uses
Some factors that buyers should consider as they purchase gaskets include:
The amount of force the two surfaces will exude on the gasket
The degree of surface unevenness (which dictates how thick the gasket should be)
The fluids and any ambient contaminants
The compressibility of the gasket material
If you know all the details of the application environment, you can choose gasket materials that withstand exposure to water, acidic or alkaline chemicals, oxidation, and more factors as needed. You can also pick gaskets with the right thickness, longevity, and malleability.
Selecting the right characteristics prevents gasket failure. These parts can fail if they’re exposed to chemicals that degrade the material or if the forces acting on the gasket are too great. This guide will focus on the six most important tips for choosing the perfect gasket for your needs:
Metal gaskets work best in extremely high-pressure applications. They create an initial line contact or contain the fluid through wedging once the two flush connection surfaces touch. Metal gaskets are also known as ring gaskets, and have either an ovular or octagonal cross-section. Octagonal cross sections provide a great deal of strength in the face of high pressure, such as the BX type that can handle 20,000 psi. Metal gaskets are commonly used in oil and gas industrial systems and secured with high-tension bolting.
Non-metallic, or soft, gaskets, compress between two surfaces with little tension or pressure. This makes them ideal for applications where the fluid contents have low pressure levels and can’t force a leak pathway through the gasket. Soft gaskets are affordable, easy to find in different materials and specifications, and able to be used in low-temperature applications.
One common non-metallic material option, graphite, can also be used in high-temperature applications up to 500°C. These gaskets come in full face varieties, which cover the entire face of a connecting surface, and inside bolt circle gaskets, which cover a smaller ring of surface area on the face; one common application for full face gaskets is temporarily connecting utility lines.
Composite gaskets use both metal and non-metal materials, giving them the ability to provide a reliable seal in a variety of environments with different pressure and temperature factors. They are commonly used in male-female, raised face, and tongue-and-groove flanges. Because they contain less metal, they are often more affordable.
Elastomeric: Elastomers are polymers with similar stretch and flexibility to rubber. Elastomeric gaskets are commonly used in utility applications alongside non-metallic gaskets. While these gaskets are elastic and can be deformed, they’re incompressible and can’t reduce in volume.
Fibrous: Fibrous gaskets are another specialized type of non-metallic gasket. This category includes materials such as aramid, carbon, and glass fibers, cork, mica, and more. Each material offers very distinct properties.
2. Evaluating Fluid Temperature, Corrosive Properties, and Pressure
When gaskets aren’t properly aligned to the application environment’s temperature, materials, or pressure, they are at an increased risk of failure. Each gasket’s material is best suited for a specific range of fluid or ambient temperature; silicone, for example, has a much wider temperature range (-30°F to 350°F) than neoprene, which is only viable at temperatures between 30°F and 180°F. One of the first considerations when choosing a gasket material is to know the minimum and maximum operating temperatures of the fluid.
The chemical makeup of the contained fluids should also determine which material your gasket has. Factors such as pH level, oil or water content, oxidation qualities, and more can corrode or destroy different materials through regular or irregular exposure.
Gaskets also perform differently depending on the pressure levels. Non-metallic gaskets, which can provide a compressed seal at relatively low pressures, cannot provide adequate resistance if the contained fluid is too pressurized; the fluid can force a path through the gasket’s seal. Synthetic rubbers, for example, often have a cap of 60 psi for reliable performance. Metallic gaskets, on the other hand, are well matched to the extremely high pressures in oil and gas processing plants.
3. Choosing the Best Types of Gaskets
Once you know which material is best for the end application, you can select the right type, or structure, of the gasket. Some popular varieties include:
Jacketed Gaskets: These have a soft non-metallic interior and a metallic coating. Jacketed gaskets are available in many varieties, such as single- or double-jackets (which have a coating on one or both sides), corrugated jackets, and more. The metallic coating gives non-metallic gaskets better resistance to damage.
Solid Gaskets: These solid metal gaskets are extremely durable, but they require a lot of compression force to create a seal.
Spiral Wound Gaskets: This gasket style has windings of metallic materials in soft, non-metallic gaskets, which combines both resistance to damage and flexibility. Piping and pumping systems often use spiral wound gaskets because of the reliable seal.
Kammprofile Gaskets: These have a metal core surrounded by non-metal material on the top and bottom. It can create a tight seal along the gasket’s edge with extra reinforcement. They’re also easier to repair than comparable composite gaskets.
4. Talking to a Gasket Design Engineer
Working with a gasket design engineer is an excellent choice for creating a custom gasket for unique applications or for expert assistance in selecting the features your system needs. If you choose the wrong materials, design style, and type, you may degrade the life span of the surrounding system. Further, mass manufacturing a flawed gasket type can result in a failed project or excessive expenses. Talk to a gasket design engineer about your design specifications and environmental factors that should shape the final product.
5. Testing for Gasket Performance
There are multiple factors to test on a new gasket design to ensure the materials, specifications, and style create an adequate and cost-effective seal. Regulatory or standardizing organizations like Underwriters Laboratories set objective standards that industrial and commercial parts must meet to be safe for sale or use. The same organizations often establish what sort of tests or testing conditions are necessary to certify that a product is safe. These tests assess a gasket’s ability to withstand temperature, chemicals, pressure, and compression to retain a seal.
6. Choosing the Right Gasket Manufacturer
The right manufacturer is essential for ensuring the material success of your project. Look for manufacturers that have experience creating gaskets for the industries or markets you serve. It’s also important to choose a manufacturer with established design, testing, and inspection capabilities, so the final product is high quality and reliable.
Why Mercer Gasket & Shim?
At Mercer Gasket, we specialize in creating custom gaskets that meet our clients’ needs. Our team of technical specialists, design engineers, and industrial experts has created custom gaskets for the refining and power generation industries. We’re an ISO 9001:2015 certified company, and our standard is 100% on-time and 100% defect-free products.
Food grade gaskets play a vital role in consumer safety, helping to maintain the sterility of consumable products. Manufacturers typically utilize these gaskets across a wide range of food-production applications to prevent contamination.
One of the most important applications for gaskets is food production; compromising the safety of food and beverages can threaten entire populations. Recent outbreaks of E. coli and other bacteria have forced companies to recall their products to prevent widespread illnesses or even death for some consumers.
For compliance and safety, companies need gaskets that adhere to the strictest FDA and USDA guidelines. A specialized rubber gasketensures no food or beverage is contaminated during any process condition. These gaskets are fabricated from materials that maintain the highest levels of sterility.
Food grade gaskets offer a fair amount of flexibility compared to gaskets manufactured for other industries. At our ISO 9001:2015-certified facilities, we offer the following methods of gasket cutting:
At Mercer Gasket, we have been specializing in the production of custom precision gaskets for 100 years. Our engineers work closely with every client to assist in the entire production process, including material selection, computer-aided design, and computerized reverse engineering. Over the years, our clients have continually trusted us to provide high-quality gasket solutions for even the most challenging projects.
For applications requiring exposure to extreme heat, silicone is a popular option. It can withstand temperatures of up to 450° F, while still functioning well in temperatures as low as -67° F. This material is often translucent, but it is also available in gray, white, and red.Read More
Like silicone, PTFE offers high levels of temperature resistance. It also provides significant anti-abrasion and anti-stick properties. This synthetic fluoropolymer is very malleable, and it is often one of the most desirable materials for food grade gaskets.Read More
Ideal for situations requiring exposure to the elements, EPDM rubber is resistant to UV light and doesn't break down in extreme weather. As such, it is a popular choice for food production in agricultural settings such as grain silos. This material is both flexible and strong, and it holds up well even when exposed to oily substances. EPDM rubber is typically black in color and provides reliable service in temperatures of -40° F to 250° F.
One of the biggest strengths of FDA Nitrile Rubber is its resistance to oil. This is particularly beneficial in the food industry since it will function well even when exposed to greasy or oily foods, particularly vegetable oils and animal fats. Nitrile can withstand temperatures ranging from -40° F to 212° F. It is most often available in black or white color options.
When compared to gaskets manufactured for the pharmaceutical industry, gaskets for the food and beverage sector have incrementally greater flexibility in design. Pharma regulations indicate that no substitutions can be made in gasket production; however, food industry gaskets can be designed with material substitutes for certain applications.
Even so, the materials for the vast majority of food and beverage gaskets have been predetermined by industry customers. While gasket manufacturers are ready and willing to provide advice, most clients select the materials they need according to size, temperature, application, media, and pressure (STAMP).
One of the most frequently used gasket types in food production is the PTFE gasket, or Teflon® gasket. Known throughout many industries for its dielectric and non-stick properties, most PTFE resins are FDA-approved for food-related applications. Other frequently used materials for food and beverage gaskets include silicone and EPDM rubber. Mercer stocks a full line of sanitary gaskets and we are also able to create many other custom gaskets using the materials above.
Compliance for Quality
Every gasket-purchasing client needs to know their products can be delivered at the highest quality standards and without contamination. Manufacturers need to ensure contamination-free products, but the need for confirmable quality assurance goes beyond that.
Gaskets and seals for the food and beverage industry need to follow strict governmental regulations and industry standards, including:
Food & Drug Administration (FDA). The FDA publishes regulations that include which manufactured materials can come in contact with food and beverage products.
United States Department of Agriculture (USDA). This organization oversees packaging materials and equipment used in meat and poultry processing.
United States Pharmacopeia (USP) Class VI. A non-governmental organization, the USP sets high standards for materials used in food and beverage processing. Class VI compounds meet the tightest requirements for non-toxicity.
Contact Us for Quality Custom Gaskets for the Food and Beverage Industry
To prevent contamination of consumables both during and after production, it is imperative to utilize high-quality FDA gaskets. Working with expert engineers streamlines this process, ensuring that you will receive products and materials that are suited to your unique needs.
AtMercer Gasket, we work at the highest levels of quality available in the industry. We are fully ISO 9001:2015 certified, ensuring that every gasket we produce meets the most stringent industrial standards and governmental regulations. Our experience in producing gaskets for the food and beverage industry extends back 20 years.
Not only do we offer gaskets in a full range of FDA- and USDA-approved materials, but we also work with customers to maintain an inventory that meets their specific requirements. Maintaining these inventories allows our clients to rest assured that their specific gasket material will be available upon request and ready for delivery. For additional material needs, our in-house group of sourcing experts can assist in selecting and procuring the necessary products for your project.
For more information about our extensive experience and expertise in producing gaskets for the food industry, please contact us or request a quote today.
Comments Off on Product Material Highlight- Cork & Rubber Gasket
Rubber cork — a combination of milled cork grain and synthetic rubber — is a specifically formulated material that has been at the forefront of gasket technology since the 1970s. Also referred to as cork rubber, this material is available in many different sizes and variations, and is used in a broad range of applications and industries.
A combination of first grade granulated cork and rubber polymer such as natural rubber, synthetic rubber, silicone, nitrile, EPDM, or neoprene, rubber cork is held together with glycerin-glue applied under heat and pressure. The resulting formulation, about 70% cork grain and 30% rubber, is highly resilient and compressible with minimal sideways flow, making it an optimal sealing and chemical solution for modern gasket applications.
Advantages of Rubber Cork
The individual properties of rubber and cork combine to make a highly resilient formulation for volatile and rigorous environments. Rubber cork provides strong resistance to oil, solvent, and fuel, as well as moderate resistance to fungus, acid, and extreme weather conditions. With the ability to withstand sideways flow, rubber cork is also impact resistant, shock absorbing, and resistant to fluid penetration.
In addition to the physical and chemical resiliency of this material, other benefits of rubber cork include high compressibility and flexibility (characteristics of cork and rubber, respectively) and a wide range of fluid compatibility. It can be used with or without a pressure sensitive adhesive (PSA) backing, as it is already an anti-slip material. As such, rubber cork also provides acoustic insulation and reduces levels of transmitted vibration.
Typical Applications and Industries
Die cut rubber cork sheets are available in a range of sizes, densities, and thicknesses for a variety of applications such as gaskets, spacers, bumpers, protective pads, stripping, electrical transformers and switchgear, and more. The versatility of rubber cork allows it to fulfill specific requirements for many industries including automotive, aviation, railroad, shipping, agriculture, petroleum and electrical.
Why Mercer Gasket?
At Mercer Gasket & Shim, we offer full face, square, and rectangular rubber cork gaskets, made either in one-piece construction or dove-tailed for larger jobs. We maintain a large inventory of rubber cork products in our 50,000 square foot manufacturing facility, allowing for a rapid turnaround of parts for our customers.
For more information about the benefits of rubber cork gaskets and rubber gaskets or to learn more about how to incorporate this versatile material into your industrial application, contact Mercer Gasket today.