Emerson TG-0807 manual Patented* Floating Rotor

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Technical Guide

DAN-LIQ-Turbine Meter-TG-0807

August 2007

Figure 4 - Rotor Assembly Cross Section

Patented* Floating Rotor

Flowing fluid enters the turbine through the forward suspension. When it encounters the sharp angle of the cone, the stream is deflected outward, increasing in velocity and causing a slight static pressure drop. As the fluid leaves the blade area, flow has redistributed. Velocity is reduced slightly and the static pressure has increased proportionally.

The difference between the two velocity pressures causes the rotor to move upstream into the fluid flow. This upstream force would be great enough to cause the rotor to strike the forward thrust bearing, were it not for the slight offset. The cross sectional area of the cone is slightly smaller than that of the rotor hub so that some of the flow impinges directly upon the rotor hub, generating a downstream thrust. As a result, the rotor floats in balance between upstream and downstream cones, pushed forward by the pressure difference across the blades and pushed backward by the flow impingement. The only bearing surface other than the measured fluid is the cemented carbide sleeve bearing insert. (See Figure 4)

In bi-directional meters, the downstream cone is replaced by a second upstream cone and rangeability in the reverse flow direction is reduced.

* U.S. PATENT NO. 3,948,099, PATENTS IN OTHER COUNTRIES

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Contents Daniel Liquid Turbine Flow Meter Technical Guide Page Foreword Table of ContentsFlow Ranges +0.15% +0.02% Turbine Meter ParametersLiquid Turbine Flow Meter System Flow Computer Turbine Meter Theory Daniel Valves In Load Rack DutyPatented* Floating Rotor Magnetic Pickoff of Rotor Velocity Surge And Pressure Relief ValvesTurbine Meter Rotor and Bearing Design Rimmed Rotors for Higher Resolution Daniel Series 1200Pre-amplifer Liquid Turbine Flow Meter Daniel Series 1200 Liquid Turbine Flow MeterSize Inches Standard Linearity Premium Linearity Size Standard Extended InchesSize Factor Inches Pulses/BBL Pulses/M Pulses/US Gal Standard Optional Daniel Series Liquid Turbine Flow Meter Daniel Series 1500 Liquid Turbine Flow MeterInches Range BBL/Hr BPH w/20% Range M 3/Hr Extended Extended MaxStandard Flow Standard Flow RangeNominal K-Factor Size Pulses/BBL Pulses/M Pulses/US Gal Rangeability of Liquid Turbine Flow Meters = 1 .7 to Meter Size Minimum Linear Maximum Linear BBL/Hr Sizing Ratio Meter Performance in High Viscosity LiquidsSmall Diameter Meter Tube Installation and Operating RecommendationsEffects of Back Pressure Back PressureTurbine Meter Instrumentation Pickoff SpecificationsPage Stirling, Scotland Europe, Middle East, Africa