PRESSURE
& BURIED VESSELS
One
of the most important and efficient technolgies to test the pressure in service condition is
the Acoustic Emission
Burring
and insulate the vessels is a technique which creates the problem of the
control of the defects which may be originated and propagated during the works.
Being sure which
probable mechanical defects will be surveyed during the manufacturer control
and in any case during the hydraulic test, it remains only the problem of the
individuation of defects originated and advanced after the hydraulic test.
These
kind of defects are due to:
-
Stress corrosion
-
Hydrogen embrittlement
-
Corrosion-Fatigue
All these defects results from the presence of particular chemical- physical
condition and evolve only whether such conditions exist.
Thereby it is necessary to make the tests in services conditions to detect
them. The preferable technique for this kind of test is the Acoustic Emission based
on surveying of the microscopical waves of deformation emitted into the
material when the cracks go on.
The Acoustic Emission Monitoring consists in the installation of some sensors
on the vessel surface connected by cable to a reader device.
The signals are transmitted on an electronic replaceable memory and
periodically transferred to a computer to elaborate them and in case
individuate whether the defects go on.
M.I.T.
Company may furnish devices, software, the service of pick data up and the
preparation of a report.
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