Accurate Level Control
Completely Automatic operation
Simple Operation
Easy Installation and Maintenance
The Cla-Val Model 428-01/628-01 Float Valve modulates to maintain a constant liquid level in a storage tank by compensating for variations in supply or demand. It can be installed to control the flow into or out of the tank by either closing on a rising level or opening on a rising level. This valve is a hydraulically operated, pilot controlled diaphragm valve The pilot control system consists of an integral variable orifice in the main valve cover and a remotely mounted float control. A slight change in liquid level moves the float control. This action varies the pressure in the valve cover, causing the main valve to seek a new position. The integral variable orifice automatically regulates the flow into the cover chamber until the valve reaches a position that is in direct relation to the position of the float control.
Installation Data The valve may be installed in any position. The remote float control may be mounted at any convenient location above the liquid level. Float rods are available in lengths from 2' to 12' in one-foot increments A stilling well(8" min. diameter) should be provided around the float if the liquid surface is subject to turbulence, ripples or wind The float control may be installed at any elevation above the valve providing that the amount of flowing line pressure(in psi) is equal to or greater than the vertical distance in feet between the valve and the float control. When a separate source of supply pressure(Option F) is used by the pilot control system, that pressure must at all times be constant and equal to or greater than the pressure at the valve inlet.