Extra Drag Disks

Hastelloy C Extra Drag Disk Arm

SKU: N/A Category:

Model Q-8N

Download Q-8N Installation Instructions

Download Q-8N Brochure

8 to 1900+ GPM, for pipes 1″ – 10″+

Component Recognized (E85349)

Noryl Engineering Plastic (PPO) Polyphenylene Oxide During normal operations flow switches increase efficiency, save time and money by the continuous monitoring of deviations from optimum flow rates. During emergency conditions flow switches signal system malfunctions such as line breakage, pump failure, incorrect valve opening or closing, pipe, valve or filter clogging, etc.

Typical Working Fluids

  • For use in corrosive liquids such as mild acid and base solutions and related fluids.
  • Extensive chemical list is available.

For use in highly particle-contaminated liquids such as:

  • Contaminated Groundwater
  • Machine Cutting Oils
  • Medium Slurries
  • Rusty Coolant Water
  • Sea Water
  • Sewage
  • Waste Water

Special Features

  • Particle contamination resistance is provided by a single convolute elastomeric seal which is continually flushed by working fluid flow.
  • Wetted surfaces of Noryl, 316 Stainless Steel, EPDM Elastomeric Standard (Viton Special Order.)
  • Continuous adjustment while operating
  • Responds to flow only, independent of line pressure, temperature, environment
  • Temperature to 180°F continuous.
  • Line pressure to 50 psig operating – 100 psig nonoperating
  • SPDT 15 amp switching capacity model or Dry Computer/PLC Interface model
  • Maintenance and checkout is a snap for your present personnel using an uncomplicated standard test meter.
  • Maximum flow range flexibility is provided by three adjustment options:
  • Option 1 – Continuous adjustment while operating via FORCE/BALANCE spring
  • Option 2 – Step incremental adjustment via drag disk size change
  • Option 3 – Continuous

Available with Optional Filter Boot For Use In Highly Particle Contaminated Liquids








  • ˜ 10% at upper end of flow range
  • ˜ 30% at lower end of flow range

Differential pressure drops across unit (Normal Operating Conditions)

  • 1″ – 3″ pipe – less than 0.5 psi
  • 4 – 10″ pipe – negligible

Working Line Pressure

  • 50 psig max. @ 180°F Max operating
  • 100 psig @ 180°F Max non-operating

Wetted Surfaces

  • Noryl – (10% glass fibers)
  • 316 Stainless Steel Standard
  • EPDM Elastomer (Viton Special Order)

Electrical Switch Characteristics

  • SPDT
  • 15 amp, 1/2 hp @ 125 or 250 VAC
  • 1/2 amp @ 125 VDC (Tungsten lamp load)
  • UL and CSA Listed
  • 10,000,000 Operations Median

Model Q-8N can also be fitted with a SPDT Gold Cross Bar Switch for computer/PLC interface. Maximum Continuous Temperature: 180°F (may be extended to 200° for short periods). Optional Filter Boot Available in EPDM, (Viton Special Order) Weight: 1/2 lb.

Installation Dimensions



Input Power Cable Interface Options


  • Installation drawing and a numbered parts list is supplied with each unit.
  • Special One Day Delivery Available.

Hysteresis (% Flow Change to Activate/Deactivate Switch)


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