The Ford #12 Pressure Reducing Valve (PRV) is for use on water lines, to reduce supply pressures from a maximum of 400 psi to desired discharge service pressure. It is primarily used on supply lines and holds reduced dead end pressure (no flow) within approximately 10% of the variation in the initial pressure.
The #12 is a 4" PRV with flanged or grooved ends. The body of the valve is cast iron, and the interior parts and mountings are bronze and brass. This is a balanced, piston type, spring actuated, direct acting valve. The piston is easily removed by taking off the bottom cap of the valve. The stainless steel spring, which does not come in contact with water, can be reached by removing the bronze bonnet which house it. The pressure adjusting screw is protected by the acorn. The heavy duty construction allows for virtually unlimited continuous usage. The piston design is much more tolerant of contaminated water than diaphragm valves, an important feature for use in mines.
With the demand for water, the velocity increases, the piston travels downward and opens the valve to a wider position. Conversely, the piston closes when the demand for water ceases. This valve gives controlled pressure together with adequate volume at all times. Any change in discharge service pressure is easily obtained, by increasing or decreasing the spring tension on the piston by means of the pressure adjusting screw. To increase discharge service pressure, turn the adjusting screw further into the valve, and to decrease discharge pressure, turn the adjusting screw out of the valve.
The operation of the valve is not affected in any way by its position. It may be installed in any position which requirements dictate. This valve operates without auxiliary pilot, diaphragm, or other super sensitive parts
Size: 4” Fig. #12
Available in Grooved or ANSI 150/300 Flanged Ends
Below is a simple drawing of where you should place air vent holes on the hush pipe leading from the discharge of a Ford #10 Balanced Tank Float Valve. The air vent holes should be no more than 1 inch from the float valve discharge (4 to 6 holes evenly spaces around the hushpipe should be sufficient). The diameter of the air vent holes should be no larger than either 3/16" to 1/4". Please note that the optimum position for the placement of the float valve is approximately 1 foot above the tank's nominal water level.