DISKFLO Butterfly Control Valve

The DISKFLO eccentric disc rotary control valve achieves bi-directional bubble-tight shutoff while maintaining low breakout torque at both high & low pressure drops. It is available in ANSI Classes 150 thru 1500 and in sizes 2 through 72-inch. This MASCOT rotary valve is available in carbon steel, 316 stainless steel and other alloys.

Eccentric Disc seating assures low breakout torque by utilizing the pressure drop across the valve to aid the seating process. Since much of the seating force is supplied by the pressure drop, the need for strong actuator seating force – and therefore breakout torque – is reduced. Combined with DISKFLO's high-thrust cylinder actuator and eccentric-cammed disc, it is possible to achieve especially high-performance throttling – even in large pressure drops close to the seat.

DISKFLO's Eccentric Cammed Disc

A double offset has been designed into the disc to lift it out of the seat immediately upon actuation. This avoids wear on the seat and disc, reducing leakage and parts replacement. It also improves throttling by eliminating friction.

DISKFLO Butterfly Control Valve Advantages & Features

  • Bubble-tight shutoff equal to ANSI Class VI
  • Low breakout torque assures accurate throttling, even close to the seat
  • Non clogging seat design
  • Easy removal

Metal Seat Eccentric-cammed disc

  • Shutoff better than ANSI Class IV
  • Disc pulls out of seat immediately, preventing seat wear
  • Accurate throttling due to disc profile when rotating into the seat

Single pivot-point, splined shaft

Lost motion minimized between shaft and actuator

Bolted seat retainer

Uninterrupted gasket surface allows for a wide variety of gasketing

Non-selective disc & shaft

  • Easier maintenance
  • Reduced cost –replace part needed, not entire assembly

Wafer body

  • Rugged and lightweight for easy handling and maintenance
  • One body serves ANSI Classes 150, 300 and 600 in sizes 2,3,4,6 & 8
  • Industry standard MSS SP-67 permits shorter flange bolting than ball or cammed valves, increasing safety and reducing possibility of leakage

Flow capacity

Capacity greater than globe, plug and cammed control valves

Concave disc

Increased flow capacity

Disc stop in body

  • Prevents damage to seat due to overstroking
  • Permits in-line disc relocation during maintenance

Wide variety of packing box configurations

Purged bonnet and lubricator options

Fully enclosed, air purged transfer case

  • Extra safety
  • Prevents atmospheric corrosion of actuator internals
  • Disc position indicator mounted on transfer case

DISKFLO also capitalizes on established features of MASCOT product lines:

Cylinder actuator

  • High thrust for high-performance throttling
  • Compact and lightweight for easier servicing and maintenance
  • Fully interchangeable with ShearStream ball valve actuator
  • Actuator air pressures allowable up to 150 psi

Wide interchangeability

  • Spare par ts stocking requirements minimized
  • Inventory costs reduced
  • Many GFLO and VFLO parts are interchangeable with DISKFLO

Available in variety of materials

Carbon steel, 316 stainless steel and other alloys

Seat interchangeability

Metal or Teflon ® seats easily installed

Spool-type four-way positioner

  • Convertable between I/P and P/P
  • Calibration and maintenance easy due to fewer parts

The combined features designed into DISKFLO create a valve measurably superior to all other rotary valves. The information and specifications contained in the following pages are provided for comparison.

Technical Specifications

Body type: Wafer, light in weight, provides large flow and minimum pressure drop
Size: 2.0" to 72.0"
Pressure Class: Up to ANSI CL 1500
Body Material: All castable alloys
End Connections: Wafer, lugged, flanged
Gland Packing: PTFE, Braided PTFE, Grafoil
Seat Ring: Clamped-in, self aligned
Disc: Double eccentric cammed
Shaft: Splined no lost motion or dead band
Characteristics: Equal percentage, linear and on-off
Actuator: Rotary spring cylinder, fully field reversible
Shut off class: With metal seat - ANSI IV and replaceable soft seat - ANSI VI