BTG Pulptec SBT-2400, Руководство пользователя

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7.1 - Process Site Selection
M2041/5en SBT-2400 Appendix 55
©BTG 2006
7 Appendix
7.1 Process Site Selection
When a process site is selected for installation there are several things to con-
sider. This chapter gives guidelines on how to select the best process site to
place the transmitter, and when flow guides and deflectors should be used.
There is a risk in certain installations that foreign objects such as large knots or
incompletely dissolved pulp lumps, could damage the transmitter blade. To
minimize possible damage, a deflector should be welded into the piping up-
stream of the transmitter.
The transmitter can be installed in a vertical, horizontal, or sloping process
line. If the transmitter is installed in a horizontal or sloping process pipe, it must
be mounted on the side of the pipe. Any other form of mounting must be avoid-
ed due to the risk of air bubbles that disturb measurement. See Fig 1.
Never install the transmitter in a pipe section with turbulent flow. Verify that the
straight pipe sections upstream and downstream of the transmitter are long
enough.
In order to accurately calibrate the transmitter with high accuracy the sampling
valve must be mounted as close to the transmitter as possible. The recom-
mendations made regarding damping zones for transmitter mounting also ap-
ply to the sampling valve. This enables disturbances from pipe bends, pumps
etc. to be avoided.
Fig 1 Mounting alternatives
for the SBT-2400