Custom nitrile gaskets and industrial rubber products provide good resistance to oils, fuels, and chemicals but have limited temperature-resistance. Nitrile rubber, a synthetic elastomer, is also known as Buna, Buna-N, and NBR. Most NBR or Buna rubber is black, but nitrile compounds in other colors are available.
Nitrile is supplied as sheets, rolls, and extrusions that support water jet cutting, a gasket fabrication process that makes fine, fast cuts without tooling or waiting for tooling. Water jet cut nitrile gaskets are cost-effective in low-to-medium volumes. These custom gaskets also support quick-turn prototyping.
Do you need custom nitrile gaskets for industrial sealing? For design assistance, help with material selection, and expert gasket fabrication, contact Elasto Proxy.
Custom Nitrile Gaskets: Advantages and Disadvantages
Nitrile rubber provides good-to-excellent resistance to oils and solvents such as:
- animal and vegetable oils
- crude petroleum oil
- kerosene and gasoline
- liquified petroleum gases
- motor oils
- mineral oil based hydraulic fluids
- silicone greases and oils
Nitrile’s advantages also include resistance to compression set, tearing, and abrasion. Typically, NBR or Buna rubber comes in durometers ranging from 20 to 95 (Share A). Nitrile seals resist water, but provide poor resistance to weather, ozone, and aging. These custom seals are unsuitable for some applications because NBR won’t withstand temperatures that are colder than -40° F (-40° C).
The resistance of nitrile custom gaskets to petroleum oils is limited by temperature. According to most chemical resistance charts, the maximum is 250° F (121° C). If your application requires oil resistance and higher temperature resistance, you might need a fluorocarbon such as Viton™ instead. Custom nitrile seals and custom nitrile gaskets are also a poor choice for highly polar solvents such as acetone.
Custom Nitrile Seals: Commodity vs. Specialty Rubber
Nitrile rubber is water jet cut from commercial and specialty grades. Commercial rubber costs less and is available in greater minimum order quantities (MOQs). Specialty rubber costs more and has higher MOQs but offers improved properties. ASTM D2000 uses the designations BF, BG, BK, and CH for both standard nitrile and specialty nitrile.
Compounders have developed different grades of nitrile rubber with enhanced material properties. For example, hydrogenated nitrile butadiene rubber (HNBR) can withstand slightly higher temperatures than NBR and provides improved resistance to polar fluids. Carboxylated nitrile butadiene rubber (XNBR) has a higher compression set than Buna-N and offers improved tear and abrasion resistance.
Custom Nitrile Rubber Products: Applications
Nitrile rubber products are used in the aerospace, defense, infrastructure, medical and health, and mobile equipment industries. Nitrile product include:
- floor mats
- hydraulic hoses
- lip seals
- oil seals
- vehicle transmission belts
Buna-N or NBR rubber is also used in appliance seals, medical gloves, the bumpers for bowling alleys, and many other types of custom seals and custom gaskets.
Choose Custom Nitrile Gaskets from Elasto Proxy
Do you need custom nitrile gaskets or other industrial rubber products? Do you have questions about NBR rubber, or are you wondering whether HNBR or XNBR could be a better choice your application? Maybe you’re considering Viton™ or a specialty grade Buna-N when a commercial NBR could meet your requirements. It’s important to avoid seal failure, but you don’t want to over-engineer your parts.
Elasto Proxy supplies custom nitrile seals and gaskets to a variety of industries. With our water jet cutting equipment, we can fabricate a custom sealing solution that meets your application-specific requirements. Nitrile isn’t the only oil-resistant rubber, but it’s a cost-effective choice compared to some other compounds. Are you ready to find out if its’ the right choice for your application?
For design assistance, help with material selection, and expert gasket fabrication, contact Elasto Proxy.