Since 1973
After Hours Service
Contact Us

EN  |  FR  |  ES

Home >> Shaft Seals >> DMR Bearing Isolators >> LN Series Bearing Isolator

LN Series - Bearing Isolator

LN – Standard non-flanged, flush mount isolator.

This non-contact, labyrinth design provides unsurpassed bearing protection for rotary shaft equipment. Constructed of chemically compatible PTFE, it is designed to retain lubrication and exclude aggressive contaminants in non-flooded applications. 


Technical Specifications

  • OPERATION TYPE: Non-Flooded MAXIMUM SURFACE SPEED: Up to 5,000 fpm (25 m/s) PRESSURE RATING: 0 psi 
  • AXIAL MOVEMENT: 0.020 inch (0.51 mm) 
  • ECCENTRICITY: 0.020 inch (0.51 mm) 
  • OPERATING TEMPERATURE: -40° to 250 °F / -40° to 121 °C 
  • SHAFT DIAMETER: 0.500 to 10.000 inch (12 to 250 mm) 
  • BORE DIAMETER: 1.250 to 11.500 inch (26 to 290 mm) 
  • O-RING MATERIALFKM is standard. Alternates available 

Performance Advantages

Machine downtime due to bearing failure is costly. By keeping lubrication in and contaminants out, ProTech bearing isolators provide reliable, two-way sealing protection of rotating equipment for extended bearing life. Labyrinth sealing technology applied to high performance materials allows the Parker ProTech LN Profile bearing isolator to operate far beyond the shaft speed limits of standard radial lip seals and avoids shaft wear. Because it is a precision-machined seal, costs can be eliminated on tooling charges, allowing retrofit of most shaft and bore combinations. 

The non-contact design has virtually no torque consumption, will not wear or groove shafts, and allows for non-lubricated dry running. It also accommodates the greatest axial movement in the industry, reducing a major factor that causes labyrinth seal failure. 

We can custom engineer solutions to meet exacting specifications for either new or retrofit applications. When used to replace lip seals, the LN Profile lowers shaft cost due to liberal surface finish specifications. 


An external O-ring on the outside diameter of the ProTech stator allows for easy seal installation, maintains a press fit in the seal housing, and provides a static seal against the bore for lubricant retention. The stator has a sophisticated series of grooves to retain oil splash, the most effective design for oil retention when compared to various competitor designs. 

The rotor uses an external O-ring to maintain a static press fit on the shaft. Since the rotor spins with the shaft, it will not wear, groove, or damage the shaft. This eliminates costs associated with having to recondition the sealing surface of the shaft. 

The rotor and stator are assembled at the factory where they are permanently unitized, allowing for a one-piece installation. This unitized design also maintains the seal’s integrity by keeping high-pressure water spray, vibration or axial movement from separating or increasing the gap between the rotor and stator. 


The LN profile is our standard design for non-flooded applications where the seal must be mounted flush in the housing. It is ideal for sealing and protecting the bearing housings of electric motors, pumps, mixers, gear boxes, blowers and custom equipment against heavy water spray and dry contaminants. The LN design is excellent for retaining grease and oil splash, however the oil level must be below the inboard oil drainback (non-flooded). 

Maximum internal pressure: 0 psi (0 bar)

The LN Profile shaft mounting positions and respective compatible lubrication types are: 

  • Horizontal Mounting: Compatible for grease, oil and dry
  • Vertical Up Mounting: Not recommended. Consider LX Profile
  • Vertical Down: Compatible for grease, and dry. Not compatible for oil


Stator & Rotor: ProTech uses, proprietary PTFE compounds making it well suited for harsh environments, such as citric acids and strong caustics. This superior chemical resistance allows for the standardization of a single material within a plant, eliminating the cost associated with stocking duplicate sizes in expensive stainless steel or other exotic materials. 

Standard chemical compatibility charts recommend PTFE for 160 chemicals in comparison to 11 for bronze and 30 for stainless steel. 

Characteristics of the various PTFE materials offered: 

  • Temperature range: -40 to 250F (-40 to 121C)
  • Higher temperature applications can be handled with alternate materials
  • Low wear, low coefficient of friction. Superior for dynamic applications
  • FDA compliant
  • Anti-microbial
  • USDA 3A Sanitary standards for food and dairy product contact

O-Rings: Come standard as FKM, but are also available in: 

  • NBR
  • FDA silicone
  • Fluorosilicone
  • EPDM
  • Aflas®

Size Range

The LN Profile is manufactured in standard shaft diameters ranging from 1/2” to 10” (12.7mm to 250mm). Because this is a precision machined seal, we can manufacture virtually any configuration. 













Translate »
Scroll to Top