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Series 442/443 Diatroller Treater Valve

The Diatroller is a combination liquid level controller and liquid valve. Closed, the force of the weighted rod on top exceeds the liquid pressure under the valve diaphragm. As the liquid level rises in the vessel, the increased head pressure raises the diaphragm, opening the valve.

Gas from the top of pressure vessels is piped to the valve diaphragm's top side to equalize pressure.

Features and Benefits  

  • Quick Change Trim - Can be changed without taking valve out of the line - reduced downtime
  • Replaceable Seat - Reduced overall cost
  • Weights Can Be Added - Meets all application demands
  • Soft Plug - Assures tight shut-off


The Series 442 Diatroller is perfect for an oil or water dump valve for treaters, free water knockouts, and gun barrels. It can also be used as a discharge valve for salt water disposal systems.

Standard Specifications  

Body Material   Cast Iron, A-126   Temperature Limits   -20 F to 250 F (-29 C to 121 C)
Body Cover Material   Cast Iron, A-126   Plug Type   Replaceable, Buna N
End Connections   2" FNPT Threaded; 3", 4" Class 125# FF Flanges.  Seat Type   Removable, Cast Iron  
Diaphragm Material   Nylon Reinforced Buna N Diaphragm   Other Wetted Parts   303 Stainless 
Maximum Differential Operating Pressure   125 psi      


Inches (mm)

Note: Dimensions -- Inches to the nearest tenth (millimeters to the nearest whole mm), each independently dimensioned from respective engineering drawings.