Plast-O-Matic Valves

Sept. 20, 2005
Plast-O-Matic Valves develop all plastic continuous degassing valve

Plast-O-Matic Valves, Inc. has developed an all-thermoplastic, automatic  continuous degassing Valve.

Series DGV was developed specifically for corrosive applications subject to  outgassing, such as sodium hypochlorite, hydrochloric acid, and ozone systems.  The normally-open valve has an internal float that pivots an arm and seal  assembly as it rises and falls. When liquid fills the system, the float rises  and the valve closes. As air or gas accumulates in the valve, it displaces  liquid and allows the float to fall, re-opening the valve and releasing the gas.  The process repeats over and over as gas occurs.

A unique assembly of o-rings is used to energize the arm and control the  pivoting action. This patent-pending design is what gives Series DGV the  capability to open repeatedly, yet seal bubble-tight as soon as liquid is  present.

When designing the piping system, it is essential that the Degassing Valve be  installed at high points in the pipeline. As outgassing occurs, it usually  accumulates at the highest points in the pipeline. A DGV installed elsewhere in  the pipeline will not likely be effective, because it doesn't "catch" air as it  passes by. It is also essential that the liquid process have a specific gravity  of .9 or higher, otherwise the float won't float.

The DGV has a ½" NPT process connection, and a 1/8" NPT outlet. Because small  amounts of liquid ? and certainly vapor ? may be expelled, the outlet should be  piped to a scrubber or other safe area when used in potentially hazardous  applications.

Valve body materials are offered in Geon PVC or Corzan CPVC, with EPDM or FKM  (Viton) seals. The float is manufactured of natural polypropylene.