12" to 18" ID X 0.275" (7.00mm) C/S Square Buna-N 70 Vulcanized O-Ring

300mm ID to 450mm ID / 12" to 18" ID

Spliced & Vulcanized O-Rings: Custom Solutions for Unique Applications

Our spliced and vulcanized O-Rings are ideal when standard O-Rings don't meet your needs or when you need a faster solution than what molded O-Rings can provide. At The O-Ring Store LLC, we expertly craft O-Rings from extruded O-Ring cord, vulcanizing them to achieve the size (ID) you require. We offer seamless spliced Standard Inch and Metric O-Rings in all standard materials, across various cross sections, as well as convenient Splicing Kits. Each O-Ring <48" undergoes rigorous inspection with the Olypsys® Large Format Grid measuring system to guarantee maximum accuracy.

Current Lead Times: Dependent on cord stock availability.

• Up to 24 O-Rings: Typically ~5 days. 
• 25-100 O-Rings: Typically ~10-15 days.
• 100+ O-Rings: Requires Custom Quote. 

This process supports custom sizes that differ from standard molded O-Rings, ensuring you receive a perfectly tailored solution.

Square O-rings - Square Cut Washer Rings

Square-rings are square cross-section seals designed to be interchangeable with standard AS568 O-Rings. Complete interchangeability within standard glands is assured in most applications.

Buna-N O-Rings 70 Duro (NBR):

The most commonly used elastomer for sealing products. Nitrile, also known as Buna-N or NBR, is a copolymer of Butadiene and Acrylonitirle. It has a temperature range of -40F to +250F and is exceptionally resistant to petroleum base oils and hydrocarbon fuels. Nitrile materials also exhibit excellent tensile strength and abrasion resistance properties. The material performs well with most dilute acids, silicone oils and lubricants and in water applications. It is not recommended for use with ketones, aromatic hydrocarbons and phosphate ester hydraulic fluids. More than 50% of the Orings sold are Nitrile Orings, commonly used in hydraulic/pneumatic motors, cylinders, pumps and valves.

Buna-N / Nitrile Recommended uses:

• General purpose sealing.
• Petroleum oils and fluids.
• Gasoline
• Hydraulic fluids
• L.P. gases
• Cold Water.
• Silicone greases and oils
• Di-ester base lubricants (MIL-L-7808).
• Ethylene glycol base fluids (Hydrolubes)

Nitrile is not recommended for:

• Halogenated hydrocarbons (carbon tetrachloride, trichloroethylene)
• Nitro hydrocarbons (nitrobenzene, aniline)
• Phosphate ester hydraulic fluids (Skydrol, Fyrquel, Pydraul).
• Ketones (MEK, acetone)
• Ozone
• Sunlight, UV
• Weather
• Strong Acids Ozone
• Automotive brake fluid

Compound Info:

• A general purpose, sulfur-cured Nitrile (Buna-N) compound
• Color: Black
• Duro: 70
• FDA: No
• M2BG 710 B14 B34 EA14 EO14 EO34 EF11 EF21 F17

Operating temperature: -40°F to +250°F (-40°C to +121°C)