Flowmeters - Cased-Hole Log Analysis and Reservoir Performance Monitoring - page 70

Where Continuous flowmeter surveys are run in barefoot completions, a
measure of the hole size is vital to the correct computation of flow rates. Such hole-
size gauging can be obtained from a through-tubing caliper of the sort illustrated in
Fig. 5.13 .
Fig. 5.13 Through-tubing
caliper. Courtesy
Schlumberger
Measurements in Deviated Holes
There are grave dangers in running flowmeters in deviated holes. Controlled experi-
ments in flow loops, where the deviated angle of the hole can be changed at will,
have shown that, if the flowmeter tool lies on the low side of the pipe, it may record
a downflow even in places where the flow is upward. Figure 5.14 illustrates the
mechanics of these erroneous measurements.
Fig. 5.14 Erroneous flow
measurement in a deviated
pipe. Reprinted with
permission of the SPE from
Hill and Dolman 1982, fig. 2,
p. 2433.©1981