Flexaseal Split Cartridge Mechanical Seal

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  • States: GA, NC, SC, TN, VA
  • Summary: The easiest installation of any split cartridge mechanical seal in the world.
  • Type: Seal
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The Style 85 Split Cartridge Mechanical Seal

The Style 85 Split Cartridge Mechanical Seal Reduces Downtime for Challenging and Time-Consuming Installations

Very good alternative to pump packing in most water and wastewater applications. 

  • The easiest installation of any split cartridge mechanical seal in the world: Simply attach 2 halves over the shaft and mount to the pump like any other cartridge seal.
  • Only split cartridge mechanical seal in the world in which just two pieces are handled: No handling of lapped faces as both are secured safely in cartridge halves. Faces can’t be cocked, chipped or scarred.
  • Only split cartridge mechanical seal in which the impeller can be adjusted without removing the seal: Simply reinstall setting clips, release set screws and adjust impeller position then re-tighten set screws and remove the clips.
  • The only split cartridge mechanical seal fully assembled, and pressure tested at the factory: We ensure the sealing integrity of each Style 85 before is sent to the field. This process gives your installation an even higher success rate.
  • No measurements, no shims, no special tools, no glue: Standard cartridge setting clips assures proper axial and radial alignment and makes installation even easier.
  • 85M model is designed specifically for mixers and agitators, centrifuges and special rotating equipment that have a much larger radial shaft run-out than typical pumps, which causes additional shaft movement.

Split Cartridge Mechanical Seal Design Features

The design of the Style 85 is like no other on the market. While most split mechanical seals are mounted outside the stuffing box and are designed to function like an outside seal, the Style 85 was engineered as a true, fully split cartridge mechanical seal.

It is a hydraulically balanced, stationary multi-spring design that is primarily mounted outside the stuffing box. These features allow the centrifugal force to keep the solids away from the seal faces while maintaining the ability to handle higher speeds, internal pressures, and misalignment.

No need to worry about solids, as the springs are protected and out of the product to eliminate clogging. The static shaft sleeve “o” ring is positioned outside of the stuffing box to assure a good sealing surface, even on worn packing sleeves!

Operating Conditions

Seal Size




1 3/4“-3”

350ºF (175ºC)

3600 RPM

250 PSI
(17 bar)

3 1/8”-3 3/4”

350ºF (175ºC)

1800 RPM

200 PSI
(14 bar)

3 7/8”-4 3/4“

350ºF (175ºC)

1800 RPM

150 PSI
(10 bar)

(125mm) and above

350ºF (175ºC)

875 RPM

100 PSI
(7 bar)

Note: Max Temperature / pressure / speed indicate operating extremes independently and do not imply the seal will function at these extremes at the same time.


Industries across the board can benefit from our seals.  In particular,

  • Pulp & Paper – reducing water consumption/usage as well as minimizing environmental impact in a cost-effective manner
  • Refinery/API – Emissions Control, Toxic/Flammable/Abrasive/Corrosive Fluids, High speeds, High pressures and High temperatures
  • Wastewater – Eliminating water flush, Abrasive/Corrosive Fluids
  • Pharmaceutical – Clean Rooms, Purification, Distillation, Product containment
  • Mining - Eliminating water flush, Abrasive/Corrosive Fluids
  • Marine – Saltwater corrosion, Off-shore locations, Space constraints, Water pollution
  • Chemical Processing – Toxic/Volatile/Flammable/Corrosive/Abrasive fluids, Vacuum & Cryogenic applications, EPA regulations
  • Power – High pressure, Environmental controls, Abrasive/Corrosive/Erosive fluids
  • Food/Beverage – Hygienic/Sanitary requirements, Emissions control, Temperature control, FDA regulations

Specific applications that benefit from our innovative seal designs include:

  • Boiler-feed/Condensate
  • Cryogenics
  • Emissions Control
  • High Pressure
  • High Temperature
  • Heat Transfer Fluids

Visit the Flexaseal White Paper resources area for specific case studies on these applications.

How to Change Mechanical Packing to a Split Cartridge Mechanical Seal

Braided packing has long been the solution for large paper pulp transfer equipment due to its low upfront cost and ability to be installed and removed without complete equipment disassembly. Braided packing does come with its downfalls, however:

  • Requires permanent high-flow flush to lubricate packing.
  • Can result in permanent damage to the shaft or shaft sleeve, thus requiring equipment disassembly and replacement of components.
  • Ongoing adjustments to the packing follower are necessary to decrease leakage as packing wears.
  • Frequent maintenance and adjustments result in decreased equipment availability and increased labor hours.

While braided packing can be a solution for many services, its upkeep requirements often force operators and maintenance personnel to consider the option of mechanical seals. When considering the broad range of mechanical seal styles and products to replace braided packing, the most readily implemented, effective, and reliable is a split cartridge mechanical seal with a Pack-Ryt® ORM (O-ring mount design) bearing/bushing system.

How to Easily Install a Style 85 Split Cartridge Mechanical Seal

The Flexaseal Style 85 fully split cartridge mechanical seal coupled with an API 682 Plan 32 external flush and a Pack-Ryt® ORM is an excellent option in a wide variety of services such as the common light slurry applications seen in paper pulp equipment.

Diagram of API 682 Mechanical Seal Piping Plan 32

A split Pack-Ryt® ORM and Style 85 seal allow for a rapid conversion in the field as well as simple and efficient service after installation. The Flexaseal Style 85 split cartridge mechanical seal is a true two-piece installation, with minimal handling of parts and a quick install. The mechanic simply removes the existing packing and packing gland, reconditions the seal chamber sealing surfaces, and then mounts the split mechanical seal system without having to disassemble the equipment. Large equipment (e.g. split case pumps) that may have been a timely and costly endeavor to disassemble can now service the mechanical seal without handling the casing or rotating elements.

The Pack-Ryt® ORM not only dramatically decreases flush water consumption with its tight radial clearance over the shaft, but it also provides extra radial shaft support in a non-galling and self-lubricating composite material for added longevity. A Pack-Ryt® ORM reduces flush water entering the process stream to a small fraction of the original flow rate as compared to mechanical packing. Eliminating radial shaft movement greatly increases seal life and improves performance and because mechanical seals limit the rotating contact area to the seal faces only, the large amounts of shaft or sleeve wear from packing contact are eliminated.

The Style 85 split cartridge mechanical seal is designed to be installed outside the seal chamber and away from any packing-worn sleeve surfaces, meaning that pump sleeve replacement (and equipment teardown) is only necessary in the most severe cases. Flexaseal can also provide the appropriate split adapter plate to house the Pack-Ryt® ORM and permit the mounting of our standard seal to your specific equipment.

With paper pulp services that can plug flush lines or impact normal seal operation, the use of an API 682 Plan 32 will act to isolate the seal and allow it to run on clean, cool liquid for maximum seal longevity. Any existing water supply infrastructure used to cool and lubricate braided packing may also be used for the Plan 32 implementation, but users must confirm that the water supply pressure is at least 15 psi greater than the expected seal chamber pressure.

Reduce Water Consumption With a Style 85 Split Cartridge Mechanical Seal

The split sealing system described here has provided long-term cost savings and improved mean time between failure for many end-users. By working with Flexaseal’s engineering team to identify the right setup, customers can be certain they’ll realize major savings in energy & water consumption, reduce maintenance requirements, and increase equipment productivity.