FSPN Filter Vessels

Innovative Solutions. Clear Results.

FSPN Filter Vessels


  • NEW! Now accepts Pall Marksman Series filters 
  • Patented Polyloc® ring provides a hermetic seal, eliminating bypass and the need for bag hold down
  • Single-gasket lid seal minimizes spare parts, cleans easily, and allows quick bag change-out
  • Full ports assure unrestricted flow
  • Variety of NPT or flange connections and nozzle configurations fit diverse piping requirements
  • ASME Code vessels are made from durable Carbon Steel and 316 Stainless Steel standard (304 Stainless Steel and other materials are available)
  • Standard models offer versatility: One to 24 bags, 25-4800 GPM, with PSI of 100, 150 or 300
  • Choice of gasket materials allows a broad range of chemical and temperature compatibility
  • Size 1 & 2 Vessels in 304Ss and 316SS are available with NSF Standard 61 Certification
  • Manual and hydraulic lid lifts are economical and easy to use
  • Easy Open Lid option, available on all multi-bag units, greatly reduces change-out time and improves safety
  • Many standard models, both single- and multi-hole units, are in stock for 24-hour shipment
  • Custom filter vessels available to fit your specifications

About FSPN Filter Vessels

The FSPN line of filters cover nearly every fluid application need. From the compact FSPN-20 miniature single bag filter vessel to the large multi-bag designs, we have exactly what your flow demands require. The FSPN vessels can also be equipped with a variety of lid opening styles including manual, hydraulic, spring assist and Easy Open.

FSPN filter vessels using size 1 and 2 filter bags are designed, built and stamped to meet code requirements in our own ASME Code manufacturing facilities. Standard equipment features like the single-gasket seal, with sturdy perforated metal baskets provide durable and consistent performance.

Video: How to Install a Bag Properly

Special Promotions Overstock Filter Vessels

Dimensional Drawings


Housing Materials

  • 304 stainless steel
  • 316 stainless steel
  • Carbon steel

Gasket Materials

  • Buna
  • Buna white FDA
  • EPR
  • Viton®
  • Viton® Teflon® encapsulated

Number of Bags


Filter Bag Size

Single Bag Design: 1, 2, 3, 4
Multi-Bag Design: 1,2

Maximum Operating Pressure

150 PSI (10.34 Bar)

Design Temperature Range

Carbon Steel: 20 to 500°F (-6 to 250°C)
Stainless Steel: -20 to 250°F (-28 to 121°C)

Non-Wetted Parts

Carbon Steel: Carbon Steel
Stainless Steel: May contain some plated Carbon Steel materials


Flange or NPT

Surface Finish

Carbon Steel: Acrylic enamel painted exterior
Stainless Steel: Light sand blast

Code Stamp (Size 1, 2 only)

ASME Sect VIII, Div 1, "U" or "UM" stamp

PolyLoc® Bag Seal

Positive Bag Seal without manual hold down

Lid Opening

Hinged or swing bolt with manual davit lid lift
See options for alternate set-up

Options & Accessories


  • Lid Opening types:
    • Hydraulic Lid Lift with swing bolts
    • Spring Assist with swing bolts
    • EZ Open lid
  • 100 & 300 PSI designs available (available on most models)
  • CRN & CE code designs
  • NSF 61 Certification available with FSPN Size 2 Vessels in 304 SS and 316 SS Solid Teflon or flat-gasket design
  • Partial heat jacket or full jacket
  • Corrosion allowance
  • Mesh lined and heavy-duty rim baskets
  • Hastelloy C, Alloy 20, 2205 Duplex (other materials by request)
  • Sanitary or Victaulic connections (other connection types by request)


Chemical Compatibility


  • Recommended for most conditions up to the maximum temperature of the material. Recommended for most conditions up to the maximum temperature of the material.
  • Fair. May be acceptable, but testing is recommended. Fair. May be acceptable, but testing is recommended.
  • No data available. Customer testing required. No data available. Customer testing required.
  • Not recommended. Not recommended.


Download literature pertaining to this product

Download full product catalog

 Other FSPN Literature:

FSPN Inlet/Outlet Configuration Diagrams

FSPN Model Flow Rates

How to Order

Download ordering instructions in PDF format

Locate your representative or call 1.800.348.3205.

Bag Vessel Sizing Calculator

Results are approximate. Filter Specialists, Inc. makes no guarantees regarding their accuracy.

Measurement Preference
Process Conditions
Bag specifications



Process Condition values must not be zero Limit for viscosity is 10,000 centipoise Please enter a valid number. Number of bags used must be a positive integer Bag bags required Vessel Type Total PSI