Buna-N (Nitrile) Gasket Material

Buna-N (nitrile) is the default gasket material for petroleum oils, greases, hydraulic fluids and water at everyday temperatures, at low cost. The Parker O-Ring Handbook (ORD 5700) rates the family from -34 C (-29 F) to 100 C (212 F) continuous, with low-temperature compounds to -57 C and short-term service to 121 C. Conquest cuts nitrile sheet gaskets on the waterjet, including cork-nitrile composite sheet.

What we cut

Conquest cuts sheet gaskets on a pure-water waterjet, the one product made in house. Tolerance is set to your drawing and confirmed on the quote, and the waterjet's size limits and the tolerance class for solid rubber are on the custom gaskets page. There is no die to build, so prototypes, revision changes and short runs go through the same setup as a repeat, and expensive stock nests tightly with no die-skeleton waste. Molded and lathe-cut parts, and non-sheet compounds, are supplied from our manufacturers.

We cut nitrile at 40, 50, 60, 70 and 80 Shore A on the waterjet, and 90 Shore A nitrile gaskets are cut by a cutting partner. Sheet comes in 1/16, 1/8, 3/16, 1/4 and 1/2 in thicknesses, from 36 x 36 in sheet and 36 in and 48 in rolls, in solid, sponge and cork-nitrile composite; sheet thicker than 1/4 in is reviewed on the quote.

Nitrile gasket specifications

Where nitrile gaskets work, and where they fail

Where nitrile is used, and the usual alternatives

It is usually specified for pump, gearbox, compressor and fuel-handling flanges indoors at moderate temperature. Viton is usually specified above 100 C or for aromatic fuels and solvents, EPDM for water, steam or outdoor exposure, and neoprene where weather and moderate oil meet. For bolted pipe joints, compressed non-asbestos fiber (CNAF) is the general flange gasket. The Buna-N O-ring guide covers the same material in O-ring form. A print may also call out MIL-R-6855 (now MIL-PRF-6855), the military specification for synthetic rubber sheet and shapes, which lists nitrile for its fuel- and oil-resistant Class 1; the MIL-R-6855 guide explains its classes and grades.

Sources: DLA ASSIST document records for MIL-P-25732C Notice 1 (inactive for new design, 1989), MIL-PRF-25732, MS28775, SAE AS28775, MIL-P-83461/1, SAE AMS-P-83461 and its sheet 1, SAE AS83461/1, MIL-P-5510, SAE AMS-P-5510, MS28778 and SAE AS28778 (each read 2026-09-24 or 2026-09-25); ASTM D1418-22, public abstract (read 2026-09-28); ASTM D2000-18(2024)e1, public scope (read 2026-09-25); Parker O-Ring Handbook ORD 5700 §2.2 (read 2026-09-14) and its section VII compatibility tables (read 2026-09-25); MIL-PRF-6855F with Amendment 1, the class list (paragraphs 1.2 and 6.1), read 2026-09-27.

Parker is a trademark of Parker Hannifin Corporation. Viton is a trademark of The Chemours Company. No affiliation or endorsement is implied.