EWN Pumps

Walchem's EWN-R Series electronic metering pumps offer superior high speed dosing capability with more standard features.  The flexibility of the EWN-R pump enable it to be integrated into virtually any chemical feed application using a universal-voltage, digital controller with an expanded set of control features.  With superb valve performance and advanced solenoid engineering combine to make a highly precise pump for the most demanding applications. EWN pumps have outputs up to 6.7 GPH (25.2 L/h) and a maximum pressure of 290 PSI (20 bar).  The high speed of operation results in high resolution chemical feed and long service life.  Quiet and compact, the EWN pumps primes in seconds and holds the prime reliably.


  • Standard Features:

    High Speed Performance  E-Series pumps operate up to 360 strokes-per-minute with adjustments in 1 spm increments, providing high resolution chemical feed. Adjustable stroke length further increases the ability to refine the output, making the E-Series one of the most versatile solenoid metering pumps on the market.


    Multi-function Digital Controller The controller in the EWN-R pump provides for flexible pump control including scalable Analog control, Digital Input with both Multiply and Divide capability, external stop control, or simple speed and stroke length control.  Display can be adjusted between flow rate units or % speed for easy-to-read output and quick adjustment.  The controller is universal voltage so it can be used anywhere in the world.


    Engineered Longevity All E-Series pumps feature dual bearing support.  The armature and shaft are supported with a bearing on each end, which ensures proper axial movement, enabling the E-Series to operate at 360 SPM while extending the life of the diaphragm.


    Superior Check Valve Performance Dual Check Valve Assemblies in both suction and discharge fittings feature precision ball guides and tapered seats. Precise machining and molding of parts limit valve ball travel, ensuring that balls fully seat and seal with every stroke. This superior check valve design guarantees fast priming and reliable performance.


    Flexible Connections A removable tubing insert provides flexibility of tubing sizes and eliminates twisting of the tubing during connection.  A threaded insert can be used in place of the tubing adapter to easily convert any connection to NPT.


    High Compression Ratio The compression ratio of a metering pump is important because it affects the pump’s ability to prime and vent.  The compression ratio is raised when you reduce the dead volume of the pump head during operation.  All  E-Series pumps feature a very high compression ratio that ensures proper feed especially with off-gassing products (i.e. Sodium Hypochlorite).

  • Literature

  • Standard Installation Diagrams


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