Home > Sealing > Industrial O-Ring, Buna-N

Buna-N Industrial O-Ring | Carbon Steel, 4.781" ID

Expert Overview

This industrial O-ring, manufactured from durable Buna-N and housed in a robust carbon steel housing, provides exceptional sealing capabilities. Engineered for critical applications requiring reliable performance under pressure.

StandardASME B18
MaterialCarbon Steel
FinishZinc Plated
GradeN/A
Inside Diameter4.781"
Outside Diameter8.236"
Cross Section0.231"

Detailed Engineering Specifications

Specified by design engineers worldwide, this Buna-N industrial O-ring features precise dimensions of 4.781 inches Inside Diameter (ID), 8.236 inches Outside Diameter (OD), and a 0.231-inch Cross Section (CS). The Buna-N (Nitrile) compound offers excellent resistance to petroleum-based oils, hydraulic fluids, and many other chemicals, making it suitable for moderate temperature applications. The integrated carbon steel housing enhances structural integrity and provides superior resistance to extrusion and mechanical damage in high-pressure and high-stress environments, ensuring long-term operational reliability.

🧊 Download 3D CAD Model (.STEP)

Verified Global OEM Partners

This component strictly adheres to the tolerances, material specifications, and quality benchmarks set by the world's leading industrial manufacturers.

TrelleborgEst. 1905
Sweden🇸🇪
"Engineered polymer solutions."
Market Rank
🏆 #1 Engineered Polymers
Industry Approvals
🚀 Aerospace & Subsea Approved
Warranty & Support
🛡️ High-Performance Guarantee
Green Manufacturing
🌱 Blue Dimension ESG
Certified:ISO 9001, ISO 14001
GarlockEst. 1887
USA🇺🇸
"High-performance fluid sealing."
Market Rank
🏆 Premium Fluid Sealing Leader
Industry Approvals
🚀 Nuclear & Pharma Approved
Warranty & Support
🛡️ Zero-Leak Guarantee
Green Manufacturing
🌱 Sustainable Materials
Certified:ISO 9001, FDA, NSF
FreudenbergEst. 1849
Germany🇩🇪
"Global sealing technologies."
Market Rank
🏆 Top Global Sealing Tech
Industry Approvals
🚀 Audi & Mercedes OEM
Warranty & Support
🛡️ Global Engineering Support
Green Manufacturing
🌱 Climate Neutral 2045
Certified:IATF 16949, ISO 14001

Certifications & Compliance

RoHS Compliant:Yes
REACH Compliant:Yes
Material Traceability:Available on Request
DFARS Compliant:Yes

Installation Procedure

1. Ensure the mating groove is clean, free of debris, and properly lubricated with a compatible lubricant. 2. Carefully stretch the O-ring over the shaft or into the groove, avoiding excessive stretching or nicking with sharp tools. 3. Position the O-ring squarely within the groove, ensuring no twists or distortions before assembly of mating components.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 9001:2015 Mfg
DIN EquivalentIndustry Standard
Primary StandardASME B18

Mechanical Properties

Tensile StrengthStandard Commercial Spec
Yield StrengthStandard Commercial Spec
HardnessVaries by specific batch

Chemical Composition

Carbon (C)0.28 - 0.55%
Manganese (Mn)0.60 - 0.90%
Phosphorus (P)0.04% max
Sulfur (S)0.05% max

Temperature & Environment Rating

Min Operating Temp
-20°F (-29°C)
Max Continuous Temp
400°F (204°C)
Thermal Expansion
Typical for Material Class

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
StandardVaries by dimensionContact Sales

Corrosion Resistance Guide

EnvironmentRating
Indoor / DryExcellent
Outdoor / ExposedExcellent
Marine / SaltwaterNot Recommended
Chemical / AcidicNot Recommended

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Using excessive force during installation, leading to O-ring damage.Apply gentle, even pressure during installation. Use appropriate, non-metallic tools if necessary to guide the O-ring into place.
Incorrect lubricant selection, causing O-ring swelling or degradation.Always consult chemical compatibility charts to select a lubricant that is compatible with Buna-N and the operating environment.
Installing a twisted or distorted O-ring.Visually inspect the O-ring before and during installation to ensure it sits flat and evenly within the groove, without any twists.

Common Applications

  • Hydraulic systems
  • Pneumatic cylinders
  • Automotive engine seals
  • Industrial pumps and valves

⚠️ Engineering Warnings

  • Not suitable for use with ozone, strong acids, or polar solvents.
  • Maximum service temperature for Buna-N is typically 257°F (125°C); consult specific material data sheets for precise limits.

Alternative Products to Consider

Premium Sealing equivalentHigher corrosion resistance (316 SS)
Economy Sealing optionLower cost for non-critical indoor applications

Frequently Asked Questions

Q: What is the Industrial O-Ring, Buna-N made from?

A: This Industrial O-Ring, Buna-N is manufactured from Carbon Steel.

Q: What are the main applications?

A: Hydraulic systems, Pneumatic cylinders, Automotive engine seals, Industrial pumps and valves.

Technical Schematic

O-RING SEAL DIAGRAMAS568 Standard ConfigurationID = 4.781"CS = 0.231"SPECIFICATIONSSize: -214

Torque Specifications

⚡ UNIT CONVERTER

Conversion factor: 1 ft-lb ≈ 1.356 Nm

Verified Compatibility

StatusMating ComponentStandardTorque SpecEngineering Notes
No verified compatibility data found for this component.