Description
Product details
1. PRODUCT DESCRIPTIONNRG GLOBAL INSTRUMENTS MAKE Glass Tube Variable Area Flow Meters (Rotameters) are intended for general in line and ByPass metering applications (i.e. for Gas & Liquid) where operating conditions are with the limitations of Glass metering tubes. These are the principle of Variable Area.The float moves freely up and down tapered borosilicate glass with fluid flow from bottom to top. The float takes up a position where buoyancy forces and the float weight are balanced in proportion to flow rate. The Vertical position of the float as indicated by scale is the measure of the instantaneous flow rate.2. PRINCIPAL OF OPERATIONWhen fluid or gas flows through a taper tube containing a float, a pressure difference of P1 and P2 is created between upper and lower side of the float. The float moves upwards by a force obtained by multiplying the pressure differential by the maximum cross-sectional area of the float. Due to taper tube, as the float moves upwards, the fluid passing area increases as a result of which the differential pressure decreases. Upward movement of float stops when the deadload is dynamically balanced by the differential pressure.
