An inline flow meter measures the volume of fluid moving through a pipeline. It has a built-in flow stabilizer that controls and steadies the flow profile of the process fluid. This style of flow meter is typically installed permanently in a process line. This meter does not require a straight run and hence allows the user to shorten the length of the upstream straight run, depending on the pipe diameter. Walchem offers various types of inline water flow meters for water treatment and related applications.

Our collection features the WFM series of flow meters that work on the multi-jet principle to provide dependable, accurate performance. They are available in 3/4″, 1″, 1½” and 2″ NPT sizes for flow rates from 0.22 to 132 GPM. They have a pulse output that provides a signal to a controller or to a metering pump for proportional chemical feed. WFM Series water meters have earned a reputation for having a simple, yet robust, design, fit a wide range of applications and maintain accuracy in low-quality water. The impeller is centered in a ring of jets, with inlet jets on one level and outlet jets on another. A gear train drives the register totalizer dials and magnetic indicator to send pulses proportional to the volume.

Multi-Jet Inline Flowmeters

Key Features:

  • Simple and dependable multi-jet design.
  • Available in 3/4”, 1”, 1½” and 2” NPT sizes for flow rates from 0.22 to 132 GPM.
  • A wide range of pulse rates for a variety of applications.
  • Reed switch or Hall effect sensor options.

Working of Multi-Jet Water Meters

The WFM inline flowmeters operate on the multi-jet principle. These chemical feed flow meters have a gear train that drives the register totalizer dials. Our WFM series inline chemical flow meters, depending on the model, may use either a solid-state Hall effect sensor or a reed switch. Totalizing-only models do not require a sensor. All these models have inlet and outlet ports and units with a sensor have a color coded output cable. When operating the multi-jet meter, you need to set the volume per pulse rate and note the position of the magnet pointer. It needs to be wired correctly to your remote device.

The WFM meters are velocity type meters with an impeller that rotates at a certain speed. They have multiple ports which create water flow at required rate and directions. Connected to a magnet, the impeller rotates with the spinning of this magnet. There is a magnetic dial connected on the outer side of the magnet, which moves with the spinning magnet. This movement is directly proportional to the water flow rate in the water. This position of the magnetic dial can be seen by the user on the volume display on top of the meter. This value determines the volume of water that has passed through the meter.

Installation and Maintenance of Inline Flow Meters

Installation steps for the WFM inline water flow meters.

  • Mount the flowmeter with consideration of the direction of the flow. It should be easily accessible and visible for future maintenance and reading.
  • Connect the meter to the piping system via a wrench on the same side as of the pipe connection.
  • Rotate the meter manually to view the scale depicting the water flow.
  • Ensure the upstream and downstream pipe length as well as the pipe diameter meets the requirements.
  • Depressurize the pipeline and ensure there is no contamination or dirt in the flow path around the meter. Clean the pipeline to ensure this.
  • Mount the flowmeter in the location, and connect it to the pipeline using the required seals, gaskets, and fittings.
  • Ensure the fittings are tight and there is no leakage.
  • Connect the meter’s sensor wires to the input of the measuring device as per the manufacturer’s guidelines. Install any software or control systems and ensure the wiring is correctly connected.
  • Calibrate and configure the inline flow meter depending on the size and speed of fluids passing through it, temperature requirements, flow rate requirements, and other parameters.
  • Perform an inspection by sending fluid through the lines and checking for proper operation and pulse output.
  • Ensure the controls and functions of the meter are functioning correctly and that the attached device is responding appropriately.
  • Train the personnel to handle and operate the meter in the
  • Ensure there is a periodic maintenance schedule set and followed.

Troubleshooting Tips for Inline Water Flow Meters

Several factors may impact measurement accuracy. It is always recommended to refer to the manufacturer’s instruction manual for any troubleshooting guidelines, here are some tips to troubleshoot the WFM inline flow meters.

  • Ensure the flow meter sensors are clean and the flow path is free of contamination. Ensure the screen on the inlet side is installed an clean.
  • If there are issues with sensor output or power supply, the wiring may be incorrect andshould be checked. Also, check for voltage fluctuations, interruptions in power supply, or electrical interference.
  • Ensure there is no air in the flow path as it can cause turbulence and destabilize the flow conditions.
  • Perform a regular visual inspection for any signs of wear & tear to seals, pipes, measuring elements, etc.
  • Check the operating environment for electrical noise. This may lead to unstable readings. Proper grounding of the flowmeter and the related accessories may be

Applications of Inline Flow Meters

Here are some application areas of our inline chemical flow meters.

  • HVAC systems: With their accurate flow rate measurement, our inline flow meters help control the temperature conditions and makeup water in HVAC systems, whether for hot or cold water. This helps increase their energy efficiency.
  • Water treatment processes: This is commonly used in drinking as well as wastewater treatment in municipal level water supply facilities. This helps monitor water consumption in the area.
  • Industrial processes: Water produced as a byproduct in industries is contaminated and must be treated before reusing or releasing in the environment. Inline flow meters used in industrial systems allow for proportional feed for treatment and can ensure the required flow rate is met.
  • Power generation: These meters are useful in such high pressure applications involving steam, hot water, and turbines rotating at high speeds through the flowing water.
  • Chemical and petrochemical industries: Our flow meters can withstand various chemicals, corrosive fluids, and more without compromising on the measurement accuracy. See chemical compatibility for more detailed information.

If your industrial application requires flow rate measurement of water, proportional dosing of chemical, etc., Walchem has inline flow meters to meet your application. These can be easily integrated into piping of your existing industrial systems. You can even use it for water measurement in residential premises. You can automate them through software and external control devices or access and measure the readings manually. Walchem is a reliable manufacturer of multi-jet inline flow meters made in various configurations.

Our WFM series comprises many models with different features that are sure to meet your requirement. We supply them individually as accessories to our pump and controller product lines, across the USA and offer fast turnaround times. If you have any questions regarding our inline flowmeters of any type, feel free to contact us at 508-429-1110, and we will be happy to assist!