SealSpec / Custom gaskets / Nitrile

Nitrile (Buna-N) rubber gaskets

Custom-cut nitrile (buna-n) rubber gaskets (NBR): where it works, where it fails, typical properties, and how to call it out on a drawing. Use the builder to spec your part in this material.

Typical properties

Polymer	NBR
Form	solid
Service temperature	-30 to 250 °F
Firmness	40–90 Shore A
Common thicknesses (in)	.031, .062, .093, .125, .187, .250

Typical ranges for the material family. Specific grades differ: confirm on the datasheet.

Custom nitrile (buna-n) rubber gasket example drawing with bolt holes — Example custom gasket outline

Strengths

Good resistance to petroleum oils, fuels and hydraulic fluids
Good abrasion resistance
Economical

Watch out for

Poor ozone and UV resistance outdoors
Not for ketones, brake fluid or strong acids

Typical applications

Engine and gearbox covers
Hydraulic equipment
Fuel-system flanges

Specs and standards to reference

ASTM D2000 BF/BG/BK callouts
MIL and FDA grades exist

Chemical check: see Nitrile ratings across 2,088 fluids →

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