Gasket material
Buna-N (Nitrile) Gasket Material
- Family
- NBR (nitrile)
- Standard range
- -34 C to 100 C (Parker® O-Ring Handbook ORD 5700)
- Special grades
- to -57 C, to 121 C
- Durometers
- 40 to 90 Shore A
- Standards
- ASTM D1418 NBR; ASTM D2000 BF/BG/BK
- Product
- Sheet gaskets waterjet-cut to your drawing in Orange, California
Service temperatures here are the family figures published in Parker O-Ring Handbook ORD 5700A/US §2.2; the compound datasheet and your application govern the final choice.
Every common gasket sheet material is quick for us to source, and we cut it to your print on our waterjet.
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 across the full hardness range, including cork-nitrile composite sheet.
What we cut
Conquest cuts sheet gaskets on a pure-water waterjet, the one product made in house. Typical figures for waterjet-cut gaskets, as fabricators and a waterjet maker publish them rather than a Conquest machine spec: a pure-water jet cuts sponge 2 in thick and solid rubber over 1 in with a square edge and no die concavity (Stockwell Elastomerics), leaves a kerf of 0.003 to 0.015 in (Flow International), and holds plus or minus 0.010 in on dimensions under 12 in and plus or minus 0.020 in on larger parts (NEDC, sponge and foam gaskets). 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.
Nitrile gasket specifications
| Property | Value | Source |
|---|---|---|
| Continuous service temperature | -34 C to 100 C (-29 F to 212 F); low-temperature compounds to -57 C; short term to 121 C | Parker ORD 5700 |
| Durometers cut | 40, 50, 60, 70, 80, 90 Shore A | Conquest Seal sheet list |
| Sheet thicknesses | 1/16, 1/8, 3/16, 1/4, 1/2 in | Conquest Seal sheet list |
| Sheet forms | 36 x 36 in sheet, 36 in and 48 in rolls; solid, sponge, cork-nitrile composite | Conquest Seal sheet list |
| Material designation | NBR under ASTM D1418; ASTM D2000 type-class BF, BG and BK line callouts | ASTM D2000 |
| Related O-ring specifications | MIL-PRF-25732 (MS28775), AMS-P-83461 (M83461/1), AMS-P-5510 (MS28778) | DLA ASSIST record, read 2026-09-06; the Buna-N O-ring guide |
| Cutting note | Waterjet; any cutter works on nitrile, so short runs and prototypes are the waterjet's territory | General practice |
Where nitrile gaskets work, and where they fail
| Medium or condition | Verdict | Note (Parker O-Ring Handbook ORD 5700) |
|---|---|---|
| Hydraulic oil, engine oil, grease | Excellent | The core nitrile application |
| Gasoline and diesel | Good | Aromatic-rich blends swell it more |
| Water, glycol-water coolant | Good | At moderate temperature |
| Dilute acids and alkalis | Acceptable | EPDM for hot or stronger solutions |
| Ozone, sunlight, outdoor service | Not recommended | Plain nitrile cracks; EPDM, neoprene or Viton® outdoors |
| Ketones, chlorinated solvents, aromatics | Not recommended | Swell and attack |
| Steam, glycol brake fluid | Not recommended | EPDM |
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. The Buna-N O-ring guide covers the same material in O-ring form.
Sources: AMS-P-5510; AMS-P-83461; ASTM D1418; ASTM D2000; MIL-PRF-25732; MS28775; MS28778; Parker O-Ring Handbook ORD 5700 §2.2 (read 2026-09-14); Conquest Seal sheet list (September 2026); typical waterjet figures, not a Conquest machine spec: Stockwell Elastomerics, Waterjet Cutting; Flow International, Waterjet Dictionary; NEDC, Die-Cut and Waterjet Cut Tolerances for Sponge/Foam Gaskets (each read 2026-09-24).
Parker is a trademark of Parker Hannifin Corporation. Viton is a trademark of The Chemours Company. No affiliation or endorsement is implied.
Reviewed by Grant Midstokke, Conquest Seal Corporation. Last updated September 2026. Material ranges are the published references named beside them; the sheet's own datasheet and your application govern the final choice.
Frequently asked
Are nitrile, NBR and Buna-N the same?
Yes: the ASTM designation, the common name and the old trade name for one material.
What is cork-nitrile?
Cork granules bound in nitrile rubber: compressible, conformable on rough or warped faces, oil-resistant, the classic cover and pan gasket sheet.
Can a nitrile gasket go outdoors?
Not plain nitrile; ozone and sunlight crack it. EPDM is usually specified where no oil is present, and neoprene or Viton where oil is.
Which durometer?
60 to 70 A for most flanges; softer conforms to rough faces, harder resists extrusion and bolt-load creep. See the durometer guide.
Send the Buna-N (Nitrile) gasket drawing and the quantity
A DXF, DWG or PDF of the gasket, the sheet thickness, the durometer and the quantity. Gaskets are cut in our own shop in Orange, California; a Conquest representative replies.
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