Skip To Content
  • Office Locations
search mail call
Posi Flate Butterfly Valves Overlay
  • Office Locations
  • Products
    • Inflatable Seated Butterfly Valves Heavy Duty Series 585, 586
    • Inflatable Seated Butterfly Valves Series 485, 486, 487, 488
    • Stainless Steel Butterfly Valves
    • Tork-Mate™
    • Tork-Lok™
    • Control Assembly
    • Pneumatic Positioner
    • Magna™ Flow Control Valve
    • Inflatable Seated Knife Gate
    • Double Dump Valve Assembly
    • VMAX™ Linear Vibrator
    • Pilot Operated Regulator
  • Resources
    • Application Data Worksheet
    • Seat Selection Guide
    • Operation
    • General Chemical Resistance of Elastomers
    • Elastomer and Chemical Compatibility Chart
  • Catalog
  • Applications
    • Control Cut-Off Valve Applications
    • Double Dump Valve Assembly Applications
    • Dryer Valve Applications
    • Outlet Valve Applications
    • Pneumatic Conveying Valve Applications
    • Vacuum Valve Applications
    • Other Valve Applications
  • Contact Us
search mail info@posiflate.com call +1-651-484-5800 Request a Quote

Inflatable Seated Butterfly Valves

Home > Products > Inflatable Seated Butterfly Valves

Heavy Duty Series 585, 586

Less friction, low torque, less wear, longer life.

Heavy Duty Series 585, 586

Posi-flate’s unique butterfly valve design uses air pressure to expand the seat against the disc, providing even pressure distribution for a bubble-tight seal, every time. Because the seat makes only casual contact with the disc during valve opening and closing, there is minimal disc impingement. This is in contrast to conventional butterfly valves where disc impingement leads to shaving of the seat, decreasing the overall performance and valve life.

Substantially less torque is required to open and close the Posi-flate butterfly valve, thus a smaller actuator can be used resulting in lower overall valve cost.

In actual comparison tests and documented field applications, the Posi-flate butterfly valve outperformed all other valves. In fact, a Posi-flate valve life of one to three million cycles, even in extremely abrasive applications, is not uncommon. For dry solids, gases and slurry applications, the Posi-flate inflatable seated butterfly valve is unsurpassed.

The Posi-flate Series 585/586 inflatable seated butterfly valves are designed for the most severe conditions. The seat is designed for heavy duty applications and higher operating pressures. Standard valve sizes range from 2″ (50mm) to 24″ (600mm) and fit both ANSI and metric flanges. A full line of actuators, limit switches and controls are available to suit individual applications.

Performance Features

  • Heavy duty
  • Inflatable seat compensates for disc and seat wear
  • Longer valve life
  • Minimal seat wear
  • No disc impingement
  • Ultra-low torque requirements
  • Lower actuator costs
  • More seal contact area
  • Proven excellent for abrasive and dry solids
  • Disc designed to prevent material buildup
  • Double shaft seals
  • Multiple bearings
  • Fail-safe monitoring

Temperature limits: -40° to 350° F (-40° to 175° C), varies with application and materials of construction.

Air supply: 135 psig (9.3 bar) maximum to seat, varies with materials of construction and application.

Working pressure: Full vacuum to 150 psig (10.3 bar) depending on application and materials of construction.

Operating torque: Varies with application.

Available Materials of Construction

Housing: Cast iron, stainless steel, aluminum, nickel-plated cast iron, epoxy coated cast iron, nylon coated cast iron

Resilient Seat: EPDM, Buna-N, polyurethane, fluoroelastomer, FDA silicone, FDA white Buna-N, FDA white EPDM, FDA white fluoroelastomer

585 Disc: Cast iron, 316 stainless steel

585 Disc/Shaft: 316 stainless steel (satin or polished), molded nylon over stainless steel shaft, superalloy, cast iron. PFAS-free non-stick and other custom coatings available

Bearings: Polymer, bronze

585 Disc Screws: Carbon steel, stainless steel

585 Shaft: Zinc-plated carbon steel, 316 stainless steel

Shaft Seal: Buna-N, silicone, fluoroelastomer, EPDM

Housing Gasket: Buna-N (Series 586), silicone, EPDM

Retaining Ring: Carbon steel, stainless steel

Housing Bolts: Carbon steel, stainless steel

Design features for reliable performance

Series 585
Series 585
Single piece housing with two piece disc and shaft. Sizes 4″ (100mm)* to 24″ (600mm).
* Series 585 4″ valve features a split housing for ease of assembly.

A. ACTUATOR MOUNTING FLANGE: Flange is designed for direct actuator mounting.

B. RETAINING RING: Retaining ring simplifies bearing and seal removal and ensures positive bearing retention.

C. BEARINGS: Multiple bearings substantially reduce operating friction and torque requirements eliminating any metal-to-metal contact, thus preventing shaft galling and freezing.

D. SHAFT SEALS: O-ring shaft seals insure positive sealing under the most adverse conditions.

E. SHAFT: Corrosion resistant, high strength steel shaft is easily replaceable.

F. SEAT O-RING SEAL: O-ring provides long lasting positive seal of seat inflation pressure.

G. MATERIAL SEAL: Land seal prevents material contamination of seat o-ring seal.

H. DISC/SHAFT: Integral disc and shaft with smooth, contoured surface provides minimum resistance to flow and reduces material buildup.

I. AIR INLET PORT: Oversized inlet port allows quick valve pressurization/
depressurization.

Series 586
Series 586
Split housing with one piece disc and shaft. Sizes 2″ (50mm) to 24″ (600mm).

J. DISC: Smooth contoured surface assures extended seat life and disc is easily replaceable.

K. DISC SCREWS: Self-locking screws of high tensile steel provide strong link between disc and shaft, yet allow easy disassembly.

L. HOUSING: Rugged one-piece body fits standard 125/150 class ANSI flat-faced flanges and PN 10 metric flanges.

M. HOUSING GASKET: Die cut elastomeric gasket assures leakproof housing.

N. HOUSING BOLTS: High strength steel bolts maintain structural integrity of housing under the most adverse conditions.

O. SPLIT HOUSING: Rugged two-piece body fits standard 125/150 class ANSI flat-faced flanges and PN 10 metric flanges. Minimizes assembly time and allows for integral shaft and disc.

P. RESILIENT SEAT: Easily replaceable, the inflatable molded seat has a smooth contour locking design to minimize stress and hold the seat in place, eliminating any need for flange gaskets.

Inflatable Seated Butterfly Valves Heavy Duty Series 585, 586 Bulletin – English

膨胀式蝶阀 重载系列 585, 586 公告 – 中文

Vannes Papillon à Siège Gonflable Usage Sévère Séries 585, 586 Bulletin – Français

Válvula Borboleta com Sede Serviço Pesado Inflável Séries 585 e 586 Bulletin – Portuguese

View Catalog

Posi Flate Butterfly Valves
  • Products
  • Applications
  • Office Locations
  • Blog
  • Contact Us
  • Resources
  • Sitemap
  • Terms of Service
  • Privacy Policy
  • Posi-flate
    1125 Willow Lake Blvd. St. Paul, MN 55110, USA
  • Phone: +1-651-484-5800
  • Email: info@posiflate.com

© 2026 Posi Flate Butterfly Valves., All Rights Reserved | Site created by Thomas Marketing Services