CN205538484U - Contain acoustic emission testing arrangement among gas coal petrography rupture process - Google Patents
Contain acoustic emission testing arrangement among gas coal petrography rupture process Download PDFInfo
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- CN205538484U CN205538484U CN201521075892.8U CN201521075892U CN205538484U CN 205538484 U CN205538484 U CN 205538484U CN 201521075892 U CN201521075892 U CN 201521075892U CN 205538484 U CN205538484 U CN 205538484U
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Abstract
The utility model provides a contain acoustic emission testing arrangement among gas coal petrography rupture process, including acoustic emission test system, mechanics control system and gas pressure control system and coal sample test system. Does the acoustic emission test system include display no. 1, AE winE1.86 acoustic emission automonitor, cable and preamplifier, mechanics control system includes display, servo control cabinet and pressure head, gas pressure control system includes aspiration pump, gas jar, tee bend, discharge valve, manometer and rubber tube, coal sample unstability destruction system includes cylinder body, coal sample and base, the utility model discloses the acoustic emission testing experiment of unipolar including the gas coal petrography can carry out, the utility model discloses can carry out the experiment of the acoustic emission signature among the coal petrography rupture process under the different gas pressure states, help more real research in the gas effect change of the acoustic emission signature emergence among the coal petrography rupture process down, exploit for the colliery deep and provide basic theoretical foundation.
Description
Technical field
This utility model relates to the acoustic emission test device in a kind of coal seam containing gas failure process, can apply to the desk research of coal seam containing gas characteristics of Acoustic Emission.
Background technology
In material, regional area stress is concentrated, and quick release of energy also produces the phenomenon of Elastic wave and is referred to as acoustic emission (Acoustic Emission is called for short AE), and otherwise referred to as stress wave is launched.During underground mining, acoustic emission phenomenon in coal petrography unstable failure is the most common a kind of physical phenomenon, but general human ear cannot be perceived, by acoustic emission monitor(ing) equipment, the characteristics of Acoustic Emission in coal rock dynamic disaster generating process can be monitored, find out some precursor informations before dynamic disaster occurs, prediction for coal rock dynamic disaster provides reliable parameter, and the catastrophe evolutionary process of coal seam containing gas dynamic disaster can be understood more fully, find some precursor informations in coal seam containing gas dynamic disaster generating process, by mechanical mechanism and precursor information, for coal seam containing gas dynamic disaster, the most perfect resolution and measure can be proposed.Therefore, the characteristics of Acoustic Emission in research coal rock dynamic disaster generating process is the most meaningful.
Coal deep mining faces the complex conditions of " heavily stressed, hyperosmosis (gas), High-geotemperature, exploit by force disturbance ", it is all the more serious that these factors result in the dynamic disasters such as Deep Mine coal petrography Gas Outburst and bump, and the condition occurred with bump of coal and gas prominent and form also there occurs significantly change.The condition of coal and gas prominent is changed to multiple condition by single, causes the dynamic disaster complex genesis such as coal mining environment and worsening condition, coal petrography and gas, and sudden and Important Project disaster threat increases the weight of.STUDY ON ACOUSTIC EMISSION CHARACTERISTICS in coal petrography unstable failure is concentrated mainly under single shaft, triaxial compressions by Chinese scholars at present, and it is relatively fewer that the characteristics of Acoustic Emission in coal petrography failure process is affected by research gas pressure.And when carrying out triaxial test, acoustic emission probe is substantially all the outside being placed on cylinder body, and acoustic emission signal is affected by cylinder body and oil pressure, cause the acoustic emission signal measured in experimentation the most accurate.Therefore a kind of experimental provision it is badly in need of, it is possible to realize the characteristics of Acoustic Emission determinator in coal petrography rupture process under different gas pressure effect.
Based on above technical problem, this utility model provides the acoustic emission test device in a kind of coal seam containing gas rupture process, can be monitored the characteristics of Acoustic Emission in coal petrography rupture process under different gas pressure effects.
Summary of the invention
The purpose of this utility model is to provide a kind of structure and uses simple, rationally, precision is high, acoustic emission test device in a kind of coal seam containing gas rupture process of stable performance, solves existing experimental provision and can not consider the problem that gas pressure affects in carrying out coal petrography mechanical characteristics and characteristics of Acoustic Emission experimentation.
For achieving the above object, this utility model adopts the following technical scheme that the acoustic emission test device in a kind of coal seam containing gas rupture process, it is characterized in that, it includes Acoustic Emission Testing System, Mechanical Control, gas pressure control system and coal petrography unstable failure platform, wherein, described Acoustic Emission Testing System is connected with the coal sample in described coal petrography unstable failure platform by cable and BNC connector, described Mechanical Control is connected with the piston on described coal petrography unstable failure platform, described gas pressure control system and the inner space of described coal petrography unstable failure platform, described coal sample is arranged in the cylinder body of described coal petrography unstable failure platform, and the overlying contact pressure of described coal sample is provided with described piston.
Further, as preferably, described Acoustic Emission Testing System includes display one, AE-win E1.86 acoustic emission automonitor, cable, acoustic emission probe and preamplifier, wherein, described display one uses described cable to be connected with the outfan of described AE-win E1.86 acoustic emission automonitor, the input of described AE-win E1.86 acoustic emission automonitor is connected with respective described preamplifier by described cable respectively, respective described preamplifier uses the connection corresponding with respective described acoustic emission probe of respective coaxial cable, on the sidewall being located at coal sample that each described acoustic emission probe is close to.
Further, as preferably, described Mechanical Control includes display two, SERVO CONTROL cabinet, forcing press and pressure head, wherein, described display two is connected with described SERVO CONTROL cabinet, described SERVO CONTROL cabinet connects described forcing press, and described forcing press is provided with described pressure head, and described pressure head presses on described piston.
Further, as preferably, described gas pressure control system includes air pump, gas pot, multiple threeways, air bleeding valve, Pressure gauge and rubber tube, wherein, described gas pot is connected with the cylinder body of described coal petrography unstable failure platform, and on the rubber tube that is connected with the cylinder body of described coal petrography unstable failure platform of described gas pot, threeway is provided with described Pressure gauge, on the rubber tube that described gas pot is connected with the cylinder body of described coal petrography unstable failure platform, threeway is provided with switch two, on the rubber tube that described gas pot is connected with the cylinder body of described coal petrography unstable failure platform, threeway is provided with described air pump, switch one it is provided with on the bleeding point of described air pump.
Further, as preferably, described coal petrography unstable failure platform includes base, cylinder seat, cylinder body and coal sample, wherein, described cylinder seat is arranged on described base, and described cylinder seat is sealingly disposed in described cylinder body lower end, the upper end of described cylinder body is provided with described piston, it is provided with O RunddichtringO between described piston and described cylinder body, between described cylinder body and cylinder seat, is provided with two O RunddichtringOs, described cylinder seat is provided with the pore passed for coaxial cable.
Further, as preferably, described acoustic emission probe is provided with PNC plug by coaxial cable, the coaxial cable that described preamplifier connects uses BNC connector to connect, described PNC plug is connected with described BNC connector, wherein, described BNC connector is fixedly installed in the pore on described cylinder seat, and is provided with teflin ring between described BNC connector and described cylinder seat.
Further, as preferably, described BNC connector lower end is provided with screw thread, in described BNC connector uses this threaded pore being arranged on cylinder seat.
Further, as preferably, the gas being passed through in described cylinder body is the mixed gas of gas, carbon dioxide or gas and carbon dioxide.
It addition, this utility model additionally provides a kind of method that acoustic emission test device utilized in coal seam containing gas rupture process carries out testing, it is characterised in that it comprises the following steps:
(1) first, open the described piston on the cylinder body of described coal petrography unstable failure platform, put into sample；
(2) vaseline is coated at described acoustic emission probe；
(3), after coating, described acoustic emission probe is installed, and with elastic rubber belt fixed sound transmitting probe；
(4) BNC connector and PNC plug are connected；
(5) described piston is closed in pass；
(6) cable is connected with preamplifier, and the other end of preamplifier is connected with acoustic emission automonitor；
(7) acoustic emission automonitor is connected with display；
(8) pressure testing machine is opened；Then, acoustic emission instrument is opened；
(9) gas drainage pipeline is connected with gas pot；
(10) open and only have switch one and drainage pump carries out air-discharging, wait that air arranges much the same time closing switch one；
(11) open the switch on gas pot and coal sample is carried out absorption parsing, and it is adsorbed saturated；
(12) after balance upon adsorption, debugging forcing press and acoustic emission automonitor；After debugging, set gas pressure；
(13) open forcing press simultaneously and start acoustic emission monitor(ing) software；
(14), after experiment terminates, closed gas pressurized tank switchs；
(15) open switch two, by air vent, gas is got rid of outside test chamber.
The beneficial effects of the utility model are:
(1), the acoustic emission test device in a kind of coal seam containing gas rupture process that this utility model provides, its acoustic emission test device used in this utility model a kind of coal seam containing gas failure process, can study the characteristics of Acoustic Emission of coal petrography under containing gas state；
(2), use the acoustic emission test device in this utility model a kind of coal seam containing gas failure process, can study under the conditions of different gas pressures, the diversity of characteristics of Acoustic Emission in coal petrography rupture process, and Precursor Law；
(3), using the acoustic emission test device in this utility model a kind of coal seam containing gas failure process, acoustic emission probe is close on coal petrography sample wall, it is possible to reduce the interference of other signals, improves the reliability of the acoustic emission signal gathered.
Accompanying drawing explanation
Fig. 1 is the structural representation of the acoustic emission test device in a kind of coal seam containing gas rupture process of the present utility model；
Fig. 2 is the cylinder seat sectional structure schematic diagram of the acoustic emission test device in a kind of coal seam containing gas rupture process of the present utility model；
Fig. 3 is the BNC connector attachment structure schematic diagram of the acoustic emission test device in a kind of coal seam containing gas rupture process of the present utility model.
Wherein, 1-display one；2-AE-winE1.86 acoustic emission automonitor；3-cable；4-preamplifier；5-display two；6-SERVO CONTROL cabinet；7-pressure head；8-piston；9-0 RunddichtringO；10-acoustic emission probe；11-coal sample；12-BNC plug；13-teflin ring；14-PNC plug；15-screw thread；16-cylinder seat；17-coaxial cable；18-base；19-threeway；20-Pressure gauge；21-switch one；22-air pump；23-gas outlet；24-gas pot；25-switch two；26-cylinder body.
Detailed description of the invention
Below in conjunction with accompanying drawing, this utility model is carried out detailed description.It should be appreciated, however, that being provided only of accompanying drawing is more fully understood that this utility model, they should not be understood paired restriction of the present utility model.
As Figure 1-3, this utility model provides the acoustic emission test device in a kind of coal seam containing gas rupture process, it is characterized in that, it includes Acoustic Emission Testing System, Mechanical Control, gas pressure control system and coal petrography unstable failure platform, wherein, described Acoustic Emission Testing System is connected with the coal sample in described coal petrography unstable failure platform by cable and BNC connector, described Mechanical Control is connected with the piston on described coal petrography unstable failure platform, described gas pressure control system and the inner space of described coal petrography unstable failure platform, described coal sample is arranged in the cylinder body of described coal petrography unstable failure platform, and the overlying contact pressure of described coal sample is provided with described piston.
In the present embodiment, described Acoustic Emission Testing System includes display 1, AE-win E1.86 acoustic emission automonitor 2, cable 3, acoustic emission probe 10 and preamplifier 4, wherein, described display 1 uses described cable 3 to be connected with the outfan of described AE-win E1.86 acoustic emission automonitor 2, the input of described AE-win E1.86 acoustic emission automonitor is connected with respective described preamplifier 4 by described cable 3 respectively, respective described preamplifier 4 uses the connection corresponding with respective described acoustic emission probe 10 of respective coaxial cable 17, on the sidewall being located at coal sample 11 that each described acoustic emission probe 10 is close to.
Wherein, described Mechanical Control includes display 25, SERVO CONTROL cabinet 6, forcing press and pressure head 7, wherein, described display 25 is connected with described SERVO CONTROL cabinet 6, described SERVO CONTROL cabinet 6 connects described forcing press, being provided with described pressure head 7 on described forcing press, described pressure head 7 presses on described piston 8.
Gas pressure control system includes air pump 22, gas pot 24, multiple threeways 19, air bleeding valve, Pressure gauge 20 and rubber tube, wherein, described gas pot 24 is connected with the cylinder body 26 of described coal petrography unstable failure platform, and on the rubber tube that is connected with the cylinder body 26 of described coal petrography unstable failure platform of described gas pot 24, threeway 19 is provided with described Pressure gauge 20, on the rubber tube that described gas pot 24 is connected with the cylinder body of described coal petrography unstable failure platform, threeway 19 is provided with gas outlet 23, switch 2 25 it is provided with on described gas outlet 23, on the rubber tube that described gas pot 24 is connected with the cylinder body 26 of described coal petrography unstable failure platform, threeway is provided with described air pump 22, switch 1 it is provided with on the bleeding point of described air pump 22.
Coal petrography unstable failure platform includes base 18, cylinder seat 16, cylinder body 26 and coal sample 11, wherein, described cylinder seat 16 is arranged on described base 18, described cylinder seat 16 is sealingly disposed in described cylinder body lower end, the upper end of described cylinder body is provided with described piston, it is provided with O RunddichtringO 9 between described piston 8 and described cylinder body 26, between described cylinder body and cylinder seat, is provided with two O RunddichtringOs 9, described cylinder seat is provided with the pore passed for coaxial cable 17.Acoustic emission probe 10 is provided with PNC plug 14 by coaxial cable, the coaxial cable that described preamplifier connects uses BNC connector to connect, described PNC plug is connected with described BNC connector, wherein, described BNC connector 12 is fixedly installed in the pore on described cylinder seat, and is provided with teflin ring between described BNC connector and described cylinder seat.
BNC connector 12 lower end is provided with screw thread 15, in described BNC connector 12 uses this threaded pore being arranged on cylinder seat.The gas being passed through in described cylinder body is the mixed gas of gas, carbon dioxide or gas and carbon dioxide.
It addition, this utility model additionally provides a kind of method that acoustic emission test device utilized in coal seam containing gas rupture process carries out testing, it is characterised in that it comprises the following steps:
(1) first, open the described piston on the cylinder body of described coal petrography unstable failure platform, put into sample；
(2) vaseline is coated at described acoustic emission probe；
(3), after coating, described acoustic emission probe is installed, and with elastic rubber belt fixed sound transmitting probe；
(4) BNC connector and PNC plug are connected；
(5) described piston is closed in pass；
(6) cable is connected with preamplifier, and the other end of preamplifier is connected with acoustic emission automonitor；
(7) acoustic emission automonitor is connected with display；
(8) pressure testing machine is opened；Then, acoustic emission instrument is opened；
(9) gas drainage pipeline is connected with gas pot；
(10) open and only have switch one and drainage pump carries out air-discharging, wait that air arranges much the same time closing switch one；
(11) open the switch on gas pot and coal sample is carried out absorption parsing, and it is adsorbed saturated；
(12) after balance upon adsorption, debugging forcing press and acoustic emission automonitor；After debugging, set gas pressure；
(13) open forcing press simultaneously and start acoustic emission monitor(ing) software；
(14), after experiment terminates, closed gas pressurized tank switchs；
(15) open switch two, by air vent, gas is got rid of outside test chamber.
Acoustic emission test device in a kind of coal seam containing gas rupture process that this utility model provides, its acoustic emission test device used in this utility model a kind of coal seam containing gas failure process, the characteristics of Acoustic Emission of coal petrography under containing gas state can be studied；Use the acoustic emission test device in this utility model a kind of coal seam containing gas failure process, can study under the conditions of different gas pressures, the diversity of characteristics of Acoustic Emission in coal petrography rupture process, and Precursor Law；Using the acoustic emission test device in this utility model a kind of coal seam containing gas failure process, acoustic emission probe is close on coal petrography sample wall, it is possible to reduce the interference of other signals, improves the reliability of the acoustic emission signal gathered.
Embodiment of above is merely to illustrate this utility model; and be not limitation of the utility model; those of ordinary skill about technical field; in the case of without departing from spirit and scope of the present utility model; can also make a variety of changes and modification; the technical scheme of the most all equivalents falls within category of the present utility model, and scope of patent protection of the present utility model should be defined by the claims.
Claims (7)
1. the acoustic emission test device in a coal seam containing gas rupture process, it is characterized in that, it includes Acoustic Emission Testing System, Mechanical Control, gas pressure control system and coal petrography unstable failure platform, wherein, described Acoustic Emission Testing System is connected with the coal sample in described coal petrography unstable failure platform by cable and BNC connector, described Mechanical Control is connected with the piston on described coal petrography unstable failure platform, described gas pressure control system and the inner space of described coal petrography unstable failure platform, described coal sample is arranged in the cylinder body of described coal petrography unstable failure platform, and the overlying contact pressure of described coal sample is provided with described piston.
Acoustic emission test device in a kind of coal seam containing gas rupture process the most according to claim 1, it is characterized in that, described Acoustic Emission Testing System includes display one, AE-win E1.86 acoustic emission automonitor, cable, acoustic emission probe and preamplifier, wherein, described display one uses described cable to be connected with the outfan of described AE-win E1.86 acoustic emission automonitor, the input of described AE-win E1.86 acoustic emission automonitor is connected with respective described preamplifier by described cable respectively, respective described preamplifier uses the connection corresponding with respective described acoustic emission probe of respective coaxial cable, on the sidewall being located at coal sample that each described acoustic emission probe is close to.
Acoustic emission test device in a kind of coal seam containing gas rupture process the most according to claim 2, it is characterized in that, described Mechanical Control includes display two, SERVO CONTROL cabinet, forcing press and pressure head, wherein, described display two is connected with described SERVO CONTROL cabinet, described SERVO CONTROL cabinet connects described forcing press, and described forcing press is provided with described pressure head, and described pressure head presses on described piston.
Acoustic emission test device in a kind of coal seam containing gas rupture process the most according to claim 3, it is characterized in that, described gas pressure control system includes air pump, gas pot, multiple threeways, air bleeding valve, Pressure gauge and rubber tube, wherein, described gas pot is connected with the cylinder body of described coal petrography unstable failure platform, and on the rubber tube that is connected with the cylinder body of described coal petrography unstable failure platform of described gas pot, threeway is provided with described Pressure gauge, on the rubber tube that described gas pot is connected with the cylinder body of described coal petrography unstable failure platform, threeway is provided with gas outlet, switch two it is provided with on described gas outlet, on the rubber tube that described gas pot is connected with the cylinder body of described coal petrography unstable failure platform, threeway is provided with described air pump, switch one it is provided with on the bleeding point of described air pump.
Acoustic emission test device in a kind of coal seam containing gas rupture process the most according to claim 4, it is characterized in that, described coal petrography unstable failure platform includes base, cylinder seat, cylinder body and coal sample, wherein, described cylinder seat is arranged on described base, described cylinder seat is sealingly disposed in described cylinder body lower end, the upper end of described cylinder body is provided with described piston, O RunddichtringO it is provided with between described piston and described cylinder body, it is provided with two O RunddichtringOs between described cylinder body and cylinder seat, described cylinder seat is provided with the pore passed for coaxial cable.
Acoustic emission test device in a kind of coal seam containing gas rupture process the most according to claim 5, it is characterized in that, described acoustic emission probe is provided with PNC plug by coaxial cable, the coaxial cable that described preamplifier connects uses BNC connector to connect, described PNC plug is connected with described BNC connector, wherein, described BNC connector is fixedly installed in the pore on described cylinder seat, and is provided with teflin ring between described BNC connector and described cylinder seat.
Acoustic emission test device in a kind of coal seam containing gas rupture process the most according to claim 6, it is characterised in that described BNC connector lower end is provided with screw thread, in described BNC connector uses this threaded pore being arranged on cylinder seat.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105973712A (en) * | 2015-12-21 | 2016-09-28 | 河南理工大学 | Acoustic emission testing device used in gassy coal rock fracturing process |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105973712A (en) * | 2015-12-21 | 2016-09-28 | 河南理工大学 | Acoustic emission testing device used in gassy coal rock fracturing process |
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Granted publication date: 20160831 Termination date: 20161221 |