Flowmeters - Cased-Hole Log Analysis and Reservoir Performance Monitoring - page 61

Fig. 5.1 Inflatable packer
flowmeter. Courtesy
Schlumberger
The advantages of packer and basket flowmeters are:
1. In biphasic flow, holdup becomes insignificant. Because flow is restricted to a
small area, the actual flow rate in the tool is very high.
2. In inclined pipes, the problems of gravity segregation of fluids are minimized.
The disadvantages are:
1. A fairly large pressure drop develops across the tool, and this may eventually
blow the tool up-hole like a piston in a cylinder.
2. The packer bags are quite prone to mechanical wear and once a leak develops it
is impossible to get a seal and make a representative measurement.