36.5X5.3 NBR 70 ShA O-Rings

What are the 36.5X5.3 NBR 70 ShA O-Rings?

The 36.5X5.3 NBR 70 ShA O-Rings are precision metric sealing rings supplied in packs of 100 pieces, making them an ideal solution for industrial production, maintenance departments, OEM manufacturers and service workshops. Manufactured from NBR (Nitrile Butadiene Rubber) with a hardness of 70 Shore A, these O-rings are designed for reliable static and dynamic sealing in hydraulic, pneumatic and general industrial applications operating with mineral oils, greases and many petroleum-based fluids. Their standardized dimensions ensure consistent fit and dependable sealing performance across a wide range of industrial equipment.

Design and Construction

Each O-ring features a precision moulded circular cross-section designed to create an effective seal when compressed inside a correctly machined groove.

Product features include:

• Metric dimensions
• Precision moulded NBR elastomer
• 70 Shore A hardness
• Circular sealing profile
• Uniform material structure
• Supplied in an economical pack of 100 pieces

Bulk packaging is particularly suitable for companies performing routine maintenance, production assembly and inventory management.

Technical Specification

Manufacturer: GRN

Product Type: Metric O-Ring

Part Number: 36.5X5.3 NBR 70 ShA

Material: NBR (Nitrile Butadiene Rubber)

Hardness: 70 Shore A

Inside Diameter: 36.5 mm

Cross Section: 5.3 mm

Profile: Round

Colour: Black

Packaging: 100 pieces

How Does an O-Ring Work?

An O-ring seals by elastic compression.

When installed between two mating surfaces, the elastomer deforms slightly and creates continuous contact pressure that prevents leakage of liquids or gases.

As operating pressure increases, the sealing force also increases, allowing the O-ring to maintain effective sealing in both static and many dynamic applications. This simple but highly efficient sealing principle explains why O-rings are among the most widely used sealing components in industrial engineering.

Why Choose NBR 70 Shore A?

NBR remains one of the most popular sealing materials because it combines durability, flexibility and compatibility with many industrial lubricants.

Benefits include:

• Good resistance to mineral oils
• Excellent grease compatibility
• Good mechanical strength
• High abrasion resistance
• Cost-effective sealing solution
• Widely accepted industrial standard

Selecting the Correct O-Ring

Correct O-ring selection should consider:

• Inside diameter
• Cross-section
• Elastomer material
• Hardness
• Operating medium
• Working pressure
• Operating temperature
• Static or dynamic movement
• Groove dimensions
• Surface finish

Using the correct size helps maximize sealing performance and service life.

Installation Recommendations

For reliable sealing performance:

• Clean the groove before installation.
• Remove burrs and sharp edges.
• Lubricate when required by the application.
• Avoid twisting the O-ring.
• Do not overstretch during installation.
• Inspect sealing surfaces before assembly.

Proper installation is often more important than the sealing element itself.

Common Causes of O-Ring Failure

Typical causes of premature seal failure include:

• Incorrect dimensions
• Wrong elastomer selection
• Mechanical damage during installation
• Excessive compression
• Elastomer ageing
• Contaminated sealing surfaces
• Improper groove design
• Chemical incompatibility

Understanding these issues helps improve equipment reliability and reduce maintenance costs.

Industrial Applications

The 36.5X5.3 NBR 70 ShA O-Rings are widely used wherever this metric size is specified by the equipment manufacturer.

Typical applications include:

• Hydraulic systems
• Pneumatic systems
• Pumps
• Valves
• Hydraulic cylinders
• Industrial machinery
• Manufacturing equipment
• Agricultural machinery
• OEM production
• MRO maintenance

Application suitability should always be verified against the machine manufacturer's technical documentation.

OEM, Production and MRO

The 100-piece pack is designed for companies that regularly consume sealing components during production or maintenance.

It is particularly suitable for:

• OEM manufacturers
• Industrial maintenance departments
• Service workshops
• Machine rebuilding
• Preventive maintenance
• Spare parts inventory

Bulk packaging reduces handling time, simplifies stock management and ensures a consistent supply of identical sealing components.

Why Engineers Choose This Product

• Pack of 100 identical O-rings
• Metric industrial dimensions
• NBR material suitable for oil and grease applications
• Standard 70 Shore A hardness
• Reliable static and dynamic sealing
• Easy storage and inventory control
• Suitable for OEM production and MRO
• Cost-effective solution for industrial users

Frequently Asked Questions (FAQ)

How many O-rings are included in the package?

Each package contains 100 pieces.

What does 70 Shore A mean?

It is the hardness rating of the NBR elastomer measured on the Shore A scale.

Can these O-rings be used with mineral oils?

Yes. NBR is commonly used in systems operating with mineral oils and lubricating greases.

Are these O-rings suitable for hydraulic systems?

Yes, provided the size, material and operating conditions match the equipment manufacturer's requirements.

Can they be used for dynamic sealing?

Yes. NBR O-rings can be used in many dynamic sealing applications when correctly designed and installed.

Who is this packaging intended for?

The 100-piece pack is ideal for OEM manufacturers, maintenance departments, industrial service companies and workshops that require multiple identical sealing rings.