28 Research on Acoustic Emission Technology for Tank Floor …
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Table 28.1 Basic information of atmospheric sewage tank for test
Serial
number
Floor
material
Tank type
Diameter
(m)
Height
(m)
Floor
thickness
(mm)
Storage
medium
Date of
putting
into use
5412A
Q235-B
Vault
20
17.7
12.0 (edge
plate)
Sewage
2005
10.0
(Middle
plate)
by using three sensor arrangements: main collection sensor, main collection sensor
+ part of guard sensor and main collection sensor + all guard sensors, respectively,
to verify the effect and advantages of the guard sensor in suppressing noise signals of
nitrogen seal system In order to solve the problem of acoustic emission detection of
atmospheric storage tank under the condition of nitrogen sealing system online, and
expand the application scope of acoustic emission online detection of atmospheric
storage tank floor.
28.1 Test Object and Instrument
28.1.1 Test Object
The tank selected in this test is a sewage tank that has been in service for 12 years.
See the following Table 28.1 for specific parameters.
28.1.2 Test Instrument
(1) An acoustic emission detection system (Samos) with guard sensor;
(2) Low frequency sensor, frequency range: 20–100 khz;
(3) Data connection line and coaxial cable;
(4) 0.5 mm HB lead core and standard lead breaking equipment.
28.2 Test Plan
This test adopts three forms: no guard sensor, main sensor + partial guard sensor and
main sensor + global guard sensor. The arrangement height of the main acquisition
sensor is 300 mm from the bottom plate, and the arrangement height of the guard
sensor is 1300 mm. The test process is as follows: