Mechanical Pump Shaft Seal

We specialize in single spring mechanical pump shaft seals for rotary / centrifugal pump applications. It's easy to replace your pump seals if you know what they are. If you do not have a pump seal number such as XX-100, you can identify what kind of seal you have, by comparing your mechanical seal components to the drawings below.

Type 1- Type 2, Type 21

Head Types

Type 1

Type 2

Type 21

Type 21

ASP-21   ASP-1   ASP-2  

Pump Seal Dimensions


The "working length" of the seal is critical to your seal application.  To identify  the working length, measure your mechanical seal end to end, this is your seals "total length".  From this you must subtract 50% of the   uncompressed spring length. This is your mechanical seals working length.

Sizing Mechanical Pump Seals


Seat Types

cup mount seat

o-ring mount seat

L-Shape Seat

clamp mount seat

To make sure your pump seals stationary seat fits, it's a good idea to provide the inside dimension of the bore it will be fitting into.  The outside dimension of your seals stationary seat is helpful but more difficult to obtain an accurate measurement.  Most pump seal stationary seats have a rubber cup or o-ring that must be compressed when it is installed.


To decipher a mechanical seals materials code,  use the following chart

Elastomers Seal Face Metal Parts Seal Seats Springs
B. Buna A. Bronze A. Bronze A. Bronze E. Monel
V. Viton ® C. Carbon D. Brass G. Cast Iron F. Stainless
N. Neoprene H. Glass Filled PTFE E. Monel J. Ceramic  
    F. Stainless K. Niresist   
AFLAS TM M. Molded Plastic   L. Silicon Carbide  
Secondary Seals        
PTFE     Z. Tungston Carbide  
I. Non Asbestos Z. Tungten Carbide      

A sample material code could be:      B C F L F
"Inquiry Form"


 Provideing all your mechanical seal requirments


Our Select Manufacturers

  • Flow Serve
  • Borg Warner
  • Durametallic
  • AST

Our Select Manufacturers

  • JM Clipper
  • Graftech
  • Lamons
  • Vulcan


  • Call us at: 714-361-1435
  • Fax: 714-593-9701