Purchase Specification
Model No. 790-01
Pressure Reducing Valve 

Sizes:	2, 3, and 4 inch wafer style
	6, 8, 10, and 12 inch flanged
	6, 8, 10, 12 inch Victaulic¨ Ends


Installation

The Cla-Val Model 790-01 is a hydraulically operated, pilot actuated automatic control valve for pressure reducing service. The main valve consists of only two parts: a stainless steel body, and an elastomeric liner or control element. 

Pressure reducing valves are used to lower pipeline pressure to a predetermined set point. Cla-Val Model 790-01 automatically controls downstream pressure, from no flow to full open flow, without regard to changes in inlet pressure. Outlet pressure control is smooth and precise since the friction and hysteresis of the valve and pilot is negligible. 

Because the valve will not chatter or slam under low flow conditions, it is not necessary to parallel Cla-Val Model 790-01 with a second smaller size control valve to obtain accurate pressure control at low flow rates. In any size, Cla-Val Model 790-01 will control pressure right down to shutoff. 

Pressure reducing valves can be supplied as a combination with check valve. Control systems are fully piped at the factory and the Cla-Val Model 790-01 is shipped ready for installation. 

Description

Valve and control system shall lower line pressure to a predetermined set point and shall maintain that set point regardless of variations in flow or inlet pressure. Control valve shall be constructed of two parts: a stainless steel body, and an elastomeric liner or control element. Minimum rangeability shall be 500:1 based on capacity at flowing pressure conditions. Cf shall be greater than or equal to 0.9. Valve and control system shall be similar in all respects to Cla-Val Model 790-01 as manufactured by Cla-Val Co., Newport Beach, California or approved equal. 


Material Specification 

Body: 	18-8 (304L) stainless steel*	 		 
Liner:	Natural Rubber, 65 durometer (standard) Viton, EPDM, Nitrile, Silicone (available)  

Liner Retainer	18-8 (304) stainless steel*	

Pilot 		
Body: 	ASTM B62 Bronze*
Spring Cover: 	ASTM B62 Bronze*
Wetted Parts: 	Bronze/Stainless steel, Buna¨ N*

Accessories 
Shut-off Cock: 	Brass*
"Y" Strainer: 	Bronze*
Speed Controls: 	Brass*
Check Controls: 	Brass*
Control Piping: 	Copper*
Control Fittings: 	Brass*
*316 stainless steel available

Valve and control system shall be similar in all respects to Cla-Val Model 790-01 as manufactured by Cla-Val Co., Newport Beach, California or approved equal.