The NATIONAL Oil Seal 1.563x2.718x0.500 M/R NBR is designed for industrial rotary shaft applications requiring dependable lubricant retention and durable sealing performance around an inch-size shaft assembly.

Installed between a rotating shaft and stationary housing, the seal creates controlled radial contact around the shaft surface. This helps reduce oil or grease leakage while limiting the entry of dust, dirt, moisture, and abrasive contaminants into the bearing, gearbox, or transmission assembly.

The product is identified by the NATIONAL manufacturer designation M/R. Because profile codes are manufacturer-specific, the exact lip geometry, outside-diameter construction, reinforcing components, spring arrangement, and installation direction should be compared with the original seal or technical drawing before replacement.

Manufactured from NBR (Nitrile Butadiene Rubber), the sealing element is generally compatible with:

• Mineral oils
• Gear oils
• Hydraulic oils
• Bearing grease
• Petroleum-based lubricants
• General industrial lubricating fluids

NBR provides good resistance to oils, wear, and abrasion under standard industrial operating conditions. Compatibility should be confirmed before use with aggressive chemicals, high continuous temperatures, ozone-rich environments, or specialized synthetic lubricants.

The inch dimensions correspond approximately to:

Shaft diameter: 1.563 inches or 39.70 mm

Housing diameter: 2.718 inches or 69.04 mm

Seal width: 0.500 inch or 12.70 mm

The specific shaft and housing dimensions suggest that this seal may be intended for a dedicated bearing housing, gearbox, axle, transmission, or OEM industrial machine. Accurate measurement and M/R profile verification are essential before installation.

⚙️ Applications

• Industrial gearboxes
• Bearing housings
• Industrial pumps
• Mechanical transmissions
• Power transmission systems
• Agricultural machinery
• Construction equipment
• Conveyor drive assemblies
• Legacy industrial equipment
• OEM rotating machinery

🎯 Benefits

✔ Helps retain oil or compatible grease

✔ Protects bearings and rotating components

✔ Oil-resistant NBR sealing material

✔ Suitable for inch-size shaft assemblies

✔ Designed for industrial rotary applications

✔ Good resistance to wear and abrasion

✔ Suitable for maintenance and overhaul work

✔ Supports longer bearing service life

✔ OEM replacement ready when dimensions and profile match

🧠 Technical Insight

• NATIONAL M/R Seal Reference
• Inch-Size Rotary Shaft Seal
• NBR Sealing Material
• Radial Shaft-Sealing Function
• Lubricant Retention Design
• Industrial Bearing and Drive Application
• Approximately 39.70 mm Shaft Diameter
• M/R Profile Verification Required

✅ Key Features

• NATIONAL Industrial Quality
• M/R Profile Reference
• Reinforced Rotary Shaft Construction
• Oil-Resistant NBR Material
• Inch-Size Dimensions
• Suitable for Compatible Oil and Grease
• Industrial Replacement Seal
• OEM Cross-Reference Ready

📊 Specifications

Brand: NATIONAL

Model: M/R

Size: 1.563 × 2.718 × 0.500 inch

Metric Equivalent: Approximately 39.70 × 69.04 × 12.70 mm

Type: Industrial Rotary Shaft Oil Seal

Material: NBR (Nitrile Butadiene Rubber)

Profile: M/R

Construction: Manufacturer-Specific Reinforced Shaft-Seal Construction

Lip Design: M/R profile; verify against the original seal

Dust Lip: Verify from the actual M/R cross-section

Spring Type: Verify from the actual seal construction

Shaft Diameter (ID): 1.563 inches / approximately 39.70 mm

Housing Diameter (OD): 2.718 inches / approximately 69.04 mm

Width: 0.500 inch / approximately 12.70 mm

Pressure Capability: Low-pressure rotary shaft-sealing service unless otherwise specified

Lubrication: Oil and compatible grease

Temperature Range: Typically approximately -30°C to +100°C for standard NBR; verify the actual compound and operating conditions

Application Class: Industrial Bearing and Rotating Equipment

Standard: Inch-Size Industrial Seal

🔁 Equivalent

Suitable replacement for compatible:

• NATIONAL M/R Rotary Shaft Seal
• 1.563x2.718x0.500 Oil Seal
• 39.70x69.04x12.70 Rotary Seal
• Inch-Size NBR Oil Seal
• Industrial Bearing Housing Seal
• Industrial Gearbox Shaft Seal
• Pump Shaft Oil Seal
• Transmission Shaft Seal
• OEM M/R Shaft Seal
• Industrial Rotary Shaft Seal

The same dimensions alone do not guarantee interchangeability. The replacement must match the original M/R cross-section, lip orientation, outside-case construction, spring arrangement, reinforcing components, and material compound.

(Always verify dimensions, M/R profile geometry, lip direction, spring construction, shaft condition, lubricant compatibility, rotational speed, temperature, and operating conditions before ordering.)

📦 Availability

✅ In Stock

🚚 Fast Delivery Available

🌎 Worldwide Shipping Available

📦 MOQ: 1 Piece

🏭 Suitable for gearbox overhaul, bearing-housing maintenance, pump repair, transmission servicing, agricultural equipment maintenance, legacy machinery restoration, and compatible OEM replacement applications.

📲 Contact via LINE ID: dusitrea

📧 Email: sales@seal4go.com

💬 Technical support available before ordering

🔍 Assistance available for cross-reference and equivalent part identification