Page 29 - Instrumentation Reference Book 3E

14 Measurement of flow

Low differential pressure tapping

High differential pressure tapping

Spring opposed cone Spindle support bar

Low differential
High differential pressure tapping
pressure tapping
(W
Figure 1.14 (a) Theessentials of GilfloA. As flow
increases the measuring orifice moves along the control
cone against the spring bellows. Courtesy, Gervase
Instruments Ltd. (b) Gilflo B extends the principle to higher
flow. Now the orifice is fixed and the control cone moves
against the spring. Courtesy, Gervase Instruments Ltd.
Recorder
Chart drum clock chart
\ /

(C)
Figure 1.13 (a) Gate-type area meter. Courtesy, American
Society of Mechanical Engineers. (b) Gate-type area meter
corrected for velocity of approach. Courtesy, American
Society of Mechanical Engineers. (c) Weight-controlled
hinged-gate meter