pressure reducing valve (PRV) – Fig. #33

service

The Ford #33 Pressure Reducing Valve is for water on supply pressures to 400 psi, where top quality and service are required in deep mines and high rise buildings. This Ford product controls reduced pressure within approximately 10% of the variation in the supply pressure, and holds dead end pressure. 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 in mines.

construction

The #33 is made in bronze in sizes ½" to 3" inclusive. Sizes ½" to 1 ½" have threaded ends. 2", 2 ½" and 3" models come with threaded, flanged or grooved end bodies. The ½", ¾" and 1" sizes have a 1" valve body with ends tapped to the proper pipe size. It is a single seated, balanced piston type, spring actuated valve without diaphragms. There are only two wearing parts: O-rings and a disc seat, which can be replaced without removing the valve from the line. The balanced construction of this valve assures positive seating and eliminates water or air hammer. In fact, this valve is noiseless in operation. The bonnet is one complete unit which houses the spring and the piston. The piston seats itself on the bottom of the bonnet. The spring is stainless steel. By unscrewing the bonnet from the body, all the internal parts of the valve are removable in one operation. This is a noiseless non-leakable valve which can be installed within the walls.

operation

With the demand for water at a fixture, 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 pressure adjusting screw is protected by the acorn that houses it.