Allied Metrics Seals & Fasteners is proud to be the finest producer of molded rubber gaskets and molded rubber seals. Regardless of the environment or application, we have the knowledge and experience to resolve any sealing issues. We understand the critical nature of component performance and our design team consults directly with each customer to ensure the perfect final product.
When to use Different Rubber Gaskets
Gaskets are manufactured in a number of different styles. Below is a short explanation of each process so that you can choose the best option for your needs.
Molding is an excellent option for mass production of gaskets with exact dimensions and little need for finishing. To create rubber gaskets in this fashion, liquid rubber is injected into a mold at high pressure and allowed to cool into the desired shape. This form of production ensures higher precision and allows for more cost-effective mass production.
Gaskets that are created through extrusion are forced through a die to create the desired shape. The rubber used in this process must be soft enough to be easily shaped, so finishing processes such as vulcanizing and curing are performed after the gaskets are cut. Extrusion is more cost-effective than other gasket manufacturing processes, as it is easily automated and the base material can be continuously pushed through the extruder.
Die Cut Gaskets
Die cut gaskets are similar to extruded gaskets in that the shape of the gasket is cut from the base rubber material, but the gaskets are cut from a flat sheet of rubber using a die to produce the desired shape. This process is easily automated and reduces waste, as a die cutter can be used to create a number of different shapes at the same time from the same sheet of material.
Waterjet production of gaskets uses water ejected at extremely high pressure to cut the rubber. Like die cutting, waterjet manufacturing cuts the shapes out of a large flat sheet of rubber. The process can be used to cut harder materials with very precise details and is capable of cutting multiple shapes at the same time, thereby reducing material waste.
Benefits of Custom Molded Rubber Gaskets
When you choose custom molded rubber gaskets from Allied Metrics, you are guaranteed to receive the highest quality gaskets available with a number of additional advantages:
- Three dimensional geometry
- Tight dimensional tolerances
- No splices, so parting lines can be designed to minimize leak paths
- Special engraving available on the visible surface of the gasket
How to Determine Designed Compressive Force
Rubber seals and gaskets are compressed between two mating components, and the amount of compressive force necessary for them to be effective is dependent on a number of factors. The primary concerns are typically the pressure of the surrounding area and the size of the particle that is being sealed.
Gas, liquid, and oil each have different particle sizes and therefore require a different amount of compressive force to keep them from escaping a seal. The higher the pressure within the sealed area, the greater the pressure necessary to maintain the seal.
Once you have determined the basic pressure and particle size of your system or equipment, several additional material properties must be taken into consideration when determining compressive force:
- Compression set to determine the material deformation when placed under a certain amount of pressure
- Stress relaxation (creep) of the gasket material when placed under constant pressure
- Durometer readings to determine the hardness of the gasket material
Geometry of the gasket and mating surfaces
When to Use Different Materials for Gaskets
- Nitrile rubber (NBR) is oil-resistant and used in fuel systems.
- Viton® is a chemical- and heat-resistant synthetic rubber used frequently in extreme environments and applications.
- Silicone has a high compression set resistance and temperature insulation, so it is particularly useful in high-temperature applications.
- Ethylene propylene diene monomer (EPDM) is a synthetic rubber that is UV-, ozone-, and weather-resistant, making it very useful in outdoor applications.
- Hydrogenated nitrile rubber (H-NBR) is valued for its high tensile strength and resistance to chemicals, oil, and extreme heat. It is used in fuel systems for automotive and aerospace applications.
- Polyurethane rubber is flexible and ideal for use in environments where it will not be exposed to extreme temperatures or moisture. It is less expensive than silicone and is used in a variety of household items.
- Aflas® rubber resists chemicals and ozone, and is often used in chemical processes and oil and gas exploration.
- Polytetrafluoroethylene (PTFE) is extremely heat resistant and non-reactive to chemicals, which makes it common for use in chemical and industrial applications.
Choose Allied Metrics for the Best Custom Gaskets and Seals
At Allied Metrics, we can produce any seal or gasket to detailed specifications in a timely fashion using our state-of-the-art-machining capabilities. Using the latest technology, we can custom-design and create any standard or non-standard seal profile to meet your every need. Whether you require short runs, long runs, or single pieces for emergency repairs, we handle jobs of all sizes. For more information, please contact us today.
Available Materials Include:
- NBR – FDA & Standard
- VITON – FDA & Standard
- SILICONE – FDA & Standard
- H-NBR – FDA & Standard
- POLYURETHANE – Hydrolysis-Resistant, High & Low Temperature-Resistant.
- PTFE – Virgin, Glass-Filled, Bronze-Filled, Carbon-Filled, Graphite-Filled, Ekonol
- Other Materials on Request. Please Call Us for Availability.