Fiber washers (vulcanized cellulose fiber) are rigid, paper-based washers used where a hard, thin, electrically insulating spacer or gasket is needed. Unlike the flexible elastomers, fiber does not compress and seal like rubber — it is chosen for insulation, spacing and light-duty gasketing on flanges and fittings.
Temperature range
-40°F to +300°F (-40°C to +149°C).
Resistance profile
- Oil resistance: Good
- Weather resistance: Good
- Water resistance: Moderate (can swell with prolonged soaking)
- Chemical resistance: Moderate
- Hardness: Rigid — not rated on the Shore A scale
Best for
Pipe flanges, compression fittings, plumbing gaskets and electrical insulation where a rigid, insulating washer is required.
What to avoid
Avoid high-pressure steam and strong acids or alkalis. For a flexible seal or chemical exposure, choose an elastomer such as EPDM, Nitrile or Viton instead.
Sizes available
We stock fiber washers across every outside diameter, inside diameter and thickness we carry, with flat per-unit pricing and bulk discounts.
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