Balancing valve with flow meter - Caleffi

765432234567234567Advantages of balanced circuitsBalanced circuits have the following principal benefits:1. The system terminals operate correctly in heating, cooling anddehumidification without waste of energy and provide a bettercomfort.2. The pumps run in their zone of highest efficiency, thus reducingthe risk of overheating and excessive wear.3. Too high medium speeds, which can result in noise andabrasion, are avoided.4. The differential pressures acting on the regulation valves arelimited in value, thus preventing faulty operation.Operating principleThe balancing valve is an hydraulic device that allows to regulatethe medium flow rate passing through.The regulating action is made by a ball obturator (1), operated bya control stem (2). The flow rate is controlled by means of a flowmeter (3) housed in a by-pass circuit, on the valve body, that canbe shut off during normal functioning. The flow rate value isindicated by a metal sphere (4), sliding within a transparent guide(5), marked alongside by a graduated scale (6).115321765432536454Construction detailsFlow meterThe flow rate value is displayeddirectly by a flow meter housedin a by-pass circuit on the valvebody, automatically shut-offduring normal functioning.The use of a flow meter greatlysimplifies the process of systembalancing, since the flow ratecan be measured andcontrolled at any time and thereis no need for differentialpressure gauges or referencecharts.The provision of a flow meteralso means that it is notanymore necessary to calculatevalve settings at the systemdesign stage.The advantages of this solutioncan be explained as significanttime and cost saving, becausethe traditional balancing devicepresetting, performed byqualified technicians, is a longand difficult procedure.2Flow meter obturatorThe obturator (1) opens and shuts the circuit between the flowmeter and the valve. The obturator can be easily opened by pullingthe ring (2), and is closed automatically, after completion of theprocedure, by theinternal spring (3). The spring and the EPDM seal(4) guarantee over time a perfect circuit closure during normalfunctioning.The operating ring (2) is made of a material with low thermalconductivity to avoid burns if the flow meter is opened while hotmedium is passing through the valve.Ball/magnet indicatorThe ball (4) that indicates the flow rate value isnot in direct contact with the thermal mediumpassing through the flow meter.Thanks to an effective and innovative measuringsystem, the ball slides up and down in a cylinder(5) that is actually separate from the body of theflow meter. The ball is moved by a magnet (6)fixed to a float (7).This means that the flow rate indication systemremains perfectly clean and provides reliablereadings over time.43125764