Anchor Seals > Fluid Sealing Products > Mechanical Seals > Mechanical Seals 3000 Series

3B Mechanical Seals & 3B-1 Mechanical Seals

FSI 3B & 3B-1 mechanical seals are multiple-spring designed, available in both balanced and unbalanced configurations. You can get a basic 3B and 3B-1 seal for single, dual, or tandem conditions.

3000 Series mechanical seals can be custom engineered to accommodate various operating conditions as well as a wide variety of different types of equipment.


  • Normally cartridge mounted for ease of installation and equipment accommodation
  • Can be used as either a rotating spring design or as a flexible stator design depending on operating parameters
  • Required seal face designs and balance ratios can be calculated to ensure optimum performance
  • Can be furnished with pumping ring or circulating shroud for API Plan 23 or 53 operation


  • Refinery & Petrochemical Light Hydrocarbon Services
  • High Pressure Multistage Pumps
  • Circulating Water and Cooling Water Services
  • Boiler Feed Pump Applications
  • Specialty Equipment Applications


  • Close clearance restriction bushings, floating throat bushings, and lip seals for use in conjunction with API Plans 21, 23, and 32.
  • A complete line of standard and custom designed seal reservoirs to support tandem and double seal operations per API Plans 52 and 53.
  • Specifically sized and selected heat ex-changers for proper seal cooling when using API Plans 21 and 23.
  • Custom engineered bearing isolating devices for specialty equipment applications


  • Temperatures: 0°F to 500°F* (-20 C to 250 C)
  • Pressures: Up to 1200 psi* (80 Bar)
  • Shaft Speeds: Up to 4500 RPM*


  • 3B1 Mechanical seals incorporate 316 SS Standard metal components (more exotic materials available upon request).
  • Our manufacturers can provide any combination of Carbon, Silicon Carbide, or Tungsten Carbide seal faces (appropriate for the pump/seal application).
  • Anchor offers standard O-ring material such as Fluoroelastomer, Perfluoroelastomer, Aflas, EPR/EPDM, as well as commercially available elastomers.
  • ASI can provide sizes ranging from 1.00 in to 6.00 in
  • ASI can also provide the same range of sizes in metric measurements.

*As always, consult your ASI representative for applications which approach or exceed these parameters.

Anchor Seals Inc. can handle all your fluid sealing needs.