DW 181

Mechanical flow controller for clean liquids

  • Flow indication without power supply
  • Up to 30,000 l/h or 132.09 GPM (US)
  • Thread: G¾…2, ¾…2 NPT
  • -40…+300°C / -40…+570°F; max. 40 barg / 580 psig

DW 181

DW 181 Deflector plate flow controller

The DW 181 is an inline flow controller for locally indicating the flow of homogeneous clean liquids without auxiliary power. It is suitable for horizontal or vertical pipes. The flow controller can have G or NPT threaded connections with sizes ranging from sup>3⁄4…2″. The measuring tube and connection are made of either bronze or stainless steel (1.4404 /316 L). Two types of indicator are available: a linear scale with up to two alarm positions at the top and bottom of the indicator or a dial.

The DW 181 is particularly suitable for cost-effective flow detection in various applications where high accuracy is not required. It can deal with flows of up to 30,000 l/h or 132.09 GPM (US). There is also a high-temperature version on offer for operating conditions up to +300°C / +570°F. The DW 181 is available as non-hazardous, intrinsically safe and explosion-proof version.

Product highlights

  • Cost-effective inline device
  • Housing removable under process conditions
  • Permanent readings in any position
  • With dial or linear scale with up to two alarm positions
  • High reliability and repeatability (±3% of switching point)
  • Wide range of wetted parts materials
  • With optional stainless steel housing
  • Individually calibrated and tested

Typical applications


  • Cost-effective flow detection (e.g. in emergency showers)
  • Cooling systems
  • Pump protection
  • Lubrication control
  • Cavitation alarm

Conventional and nuclear power industry

  • Borated water
  • Sea water
  • Cooling water, demi water etc.
  • Effluent