Radial Shaft Seal Catalog  

INSTALLATION TRAINING
 

   

 
Installation problems frequently are diagnosed as the cause of leakage. In order to ensure optimum seal function the seal must be properly installed. Care must be taken to:
  1. Design the O.D. of the seal appropriately for the application.
  2. Design the housing to accommodate the seal.
  3. Follow recommended handling and installation procedures.

OUTER DIAMETER SEALING
 

 

Design Goals - SEAL MUST:
  • Prevent leakage at outer diameter.
  • Not rotate or come out of the bore.
  • Be compatible with the bore material.
  • Be easy to install.
  • Compensate for bore imperfections.
  • Be suited for automated installation.

SEAL O.D. DESIGN TYPES
 

TYPE

O.D. CROSS-SECTION

RUBBER

Standard

Ribbed

RUBBER & METAL COMBINED

Lead-In Gasket

Outside Edge Gasket

With Flange

METAL

Standard with & without Latex Coating

With Flange and Sealant Bead
 

NOTE:  Many custom shapes and configurations are available.
 

INFLUENCE OF THE BORE MATERIAL & SURFACE FINISH
 
  • In non-ferrous or plastic housings metal O.D. seals lose pressfit at elevated temperatures due to differences in thermal expansion.

MATERIAL

COEFFICIENT OF THERMAL EXPANSION (°C)
Carbon Steel 12 x 10-6
Aluminum & Magnesium 24 x 10-6
Plastic (Nylon) 30 ~ 300 x 10-6
Rubber 100 ~ 200 x 10-6
 
  • Rubber O.D. seals can tolerate higher levels of initial bore finish than metal O.D. types.

METAL O.D. DESIGN

RUBBER O.D. DESIGN
100  minch Ra 150  minch Ra
(2.5  mm Ra) (3.75  mm Ra)
 

BORE CONDITION AFTER INSTALLATION
 

 
  • When a rubber O.D. seal is used in the original equipment assembly, service replacement is made more reliable as the bore is not damaged. Bore damage is more acute with non-ferrous bore materials.

SEAL INSTALLATION AND REMOVAL FORCES
 

 

RUBBER O.D. DESIGN TYPES
 

NOTE:  Rubber O.D. seals require a 15 to 30 degree bore chamfer angle, 1 to 2 mm in length for a more reliable assembly.

 

O.D. SEALING SUMMARY
  

 

RECOMMENDED HOUSING
 

  

  

MAX BORE SURFACE ROUGHNESS

    

METAL O.D.

 RUBBER O.D.

100   minch Ra   

 150   minch Ra

(2.5   mm Ra)

 (3.75  mm Ra)

492 minch Rmax

(12.5 mm Rmax)

 

NOTE:  With aluminum and magnesium bores, a minimum roughness of 60  minch  Ra  (1.5 mm Ra) is recommended for improved retention of rubber O.D. seals.

RECOMMENDED INSTALLATION PROCEDURE
 
  • Prepare proper housing bore diameter and chamfer.
  • Prepare proper shaft diameter and chamfer.
  • Ensure appropriate prelubrication (usually the lubricant being sealed).
  • Use a hydraulic press or other suitable method to ensure proper force and speed are applied.
  • Use proper tools.
  • Install the seal contaminant and damage free:
    • Open only 1 package of seals at a time;
    • Installation area must be kept clean;
    • Tools, protective sleeves, and bullets must be kept clean and periodically inspected for damage.