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Black Buna-N O-ring 74 mm inside diameter 3 mm cross section pack of 25

Zoro Select

Zoro Select O-Ring 74 mm ID 3 mm Buna-N Black PK25

SKU CH-7PMM-4YMT1

Pack of 25 black Buna-N O-rings with 74 mm inside diameter and 3 mm cross-section for sealing applications

  • Metal-detectable Buna-N seals for contamination-sensitive lines
  • 74 mm ID and 3 mm cross-section fit standard metric glands
  • 70A durometer resists extrusion up to 250 °F
  • Pack of 25 reduces re-order frequency
  • Operates down to -40 °F for cold-environment reliability

Product Identity

The Zoro Select O-Ring is a metric Buna-N seal with a 74 mm inside diameter and a 3 mm cross-section. It is supplied in a pack of 25 black rings rated to a 70A durometer hardness. The material operates across a temperature range of -40 to 250 degrees Fahrenheit.

Fit and Limitations

These rings suit maintenance kits and production lines that need a medium-hard, metric Buna-N seal in this exact size. They are not FDA compliant, so they cannot be used in food or pharmaceutical contact applications. Buyers needing X-ray detectable materials or different durometer ratings must source alternative parts.

Sustained Use

The Buna-N compound maintains its sealing properties through repeated thermal cycles within the stated range. The medium-hard durometer resists extrusion and compression set during prolonged static or dynamic service. Performance remains consistent as long as operating temperatures and chemical exposure stay within material limits.

Highlights

  • Metal-detectable Buna-N seals for contamination-sensitive lines
  • 74 mm ID and 3 mm cross-section fit standard metric glands
  • 70A durometer resists extrusion up to 250 °F
  • Pack of 25 reduces re-order frequency
  • Operates down to -40 °F for cold-environment reliability

Specifications

BrandZORO SELECT

Questions about this item

What groove dimensions do I need to seal with the 74 mm inside diameter and 3 mm cross-section?

Machine a groove with a 74 mm inside diameter and 3 mm width so the ring sits flush and compresses evenly.

Will the Buna-N 70A durometer hold up against hydraulic oil in my older press?

Buna-N resists petroleum-based hydraulic fluids, and the 70A hardness handles typical press pressures without extruding.

How can I verify the rings meet the -40 °F to 250 °F range after installation?

Pressurise the system at room temperature, then cycle to the extremes; no leakage or hardening means the material is performing within spec.

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