True Union


Design Advantages

• Solid thermoplastic body and bonnet for best overall corrosion resistance.

• Extra heavy EPDM diaphragm or optional PTFE diaphragm fully backed by EPDM, for long service life under the most severe conditions.

• Fully lubricated brass stem and sleeve.

• Unique concave/convex PTFE/ EPDM diaphragm design insures PTFE barrier returns to full open position.

• Standard, adjustable full close position over travel stop to eliminate premature diaphragm failure due to overtightening.

• Full stroke, fully protected open/close position indication.

• Stainless steel or plastic encapsulated external hardware.

• Longer service life and higher Cv values than rubber lined valves.

• High pressure, temperature and vacuum service rated, suitable for most applications.

• Can be used in lined, metal FRP or thermoplastic piping systems.

• Flanged application valves designed to fit between ANSI B16.5 Class 150 flanges.


Materials Of Construction





VITON® is a trademark of DuPont Performance Elastomers

TEFLON® is a trademark of DuPont Performance Elastomers


Ansi Dimensions

Testing performed on PVC/PP/EPDM valves at 73°F water temperature, non-shock.


True Union Type Diaphragm Valves (1/2" - 2" SOC./THD./FLANGED)

Design Specifications

Thermoplastic Diaphragm Valves 1/2" - 2" Soc./ Thd.,   Flg.valves shall be molded of solid thermoplastic materials for body and bonnet. Body is of the weir configuration exhibiting large flow area and good flow control capability. Body is designed to fit between ANSI B16.5 class 150 flanges. Stem and sleeve shall be Brass. Full stroke position indication is enclosed in a clear protective cover. All external fasteners shall be either encapsulated in plastic or of stainless steel materials. Materials of construction shall be: (select as required for service)






PPO, ASTM D-4101 (standard)






PVDF, ASTM, D-3222



EPDM, Ethylene Propylene Diene Monomer
PTFE/EDPM, Teflon® (DuPont Performance Elastomers)


Positive Indicator Cover

PC, Polycarbonate, ASTM - D-2848



ABS, ASTM D-1788


NOTE: For any diaphragm application with use of sodium hypochlorite, factory must be informed prior to quote. Special application valves are required.

Not recommended for compressed air or gas service.