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Buna-N Stainless Steel O-Ring: 0.943" ID x 3.949" OD

Expert Overview

This industrial O-ring, crafted from durable Buna-N and housed in a 304 stainless steel casing, offers superior sealing performance. Its robust construction ensures reliability in challenging environments, providing a secure and long-lasting seal.

StandardDIN 933
Material304 Stainless Steel
FinishPlain
GradeN/A
Inside Diameter0.943"
Outside Diameter3.949"
Cross Section0.145"

Detailed Engineering Specifications

Trusted by engineers across multiple sectors, this Buna-N O-ring with a 304 Stainless Steel housing delivers exceptional sealing integrity. Its precise dimensions – an Inside Diameter of 0.943 inches, an Outside Diameter of 3.949 inches, and a Cross Section of 0.145 inches – are engineered for a precise fit. The Buna-N compound offers excellent resistance to oils, fuels, and hydraulic fluids, while the 304 stainless steel casing provides corrosion resistance and structural support, making it suitable for a wide range of industrial applications where both chemical compatibility and mechanical robustness are critical.

🧊 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. Inspect the groove and mating surfaces for cleanliness and damage. 2. Carefully place the O-ring into its designated groove, ensuring it is not twisted. 3. Apply a thin layer of compatible lubricant if recommended for the specific application to facilitate installation and prevent damage.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 9001:2015 Mfg
DIN EquivalentIndustry Standard
Primary StandardDIN 933

Mechanical Properties

Tensile Strength75,000 psi (515 MPa)
Yield Strength30,000 psi (205 MPa)
Elongation in 2 in.40% min
HardnessRockwell B95 max

Chemical Composition

Carbon (C)0.08% max
Chromium (Cr)18.0 - 20.0%
Nickel (Ni)8.0 - 10.5%
Manganese (Mn)2.00% max

Temperature & Environment Rating

Min Operating Temp
-320°F (-195°C)
Max Continuous Temp
1400°F (760°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 / SaltwaterGood
Chemical / AcidicNot Recommended

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Overtightening fasteners, compressing the O-ring beyond its elastic limit.Tighten fasteners to the manufacturer's recommended torque specifications to avoid over-compression and premature failure.
Using incompatible lubricants or cleaning agents that degrade the Buna-N material.Always consult material compatibility charts and use only lubricants and cleaning agents approved for Buna-N and the specific application environment.
Allowing the O-ring to twist during installation, creating a path for leakage.Ensure the O-ring is seated squarely in the groove and does not twist during assembly. Gentle rotation might be needed to seat it properly.

Common Applications

  • Hydraulic systems
  • Pneumatic cylinders
  • Fluid power equipment
  • Automotive sealing
  • Industrial machinery

⚠️ Engineering Warnings

  • Not suitable for high-temperature applications or exposure to ozone, UV, or weathering.
  • Ensure material compatibility with the specific fluid or gas being sealed to prevent premature degradation.

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 304 Stainless Steel.

Q: What are the main applications?

A: Hydraulic systems, Pneumatic cylinders, Fluid power equipment, Automotive sealing, Industrial machinery.

Technical Schematic

O-RING SEAL DIAGRAMAS568 Standard ConfigurationID = 0.943"CS = 0.145"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.