CN103412096B - Multi-parameter method for monitoring coal and gas outburst under condition of multi-field coupling - Google Patents
Multi-parameter method for monitoring coal and gas outburst under condition of multi-field coupling Download PDFInfo
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- CN103412096B CN103412096B CN201310375703.8A CN201310375703A CN103412096B CN 103412096 B CN103412096 B CN 103412096B CN 201310375703 A CN201310375703 A CN 201310375703A CN 103412096 B CN103412096 B CN 103412096B
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Abstract
The invention discloses a multi-parameter method for monitoring coal and gas outburst under the condition of multi-field coupling. The method comprises the following steps of: 1) installing a telescopic steel sleeve provided with a raw coal test specimen between a confining pressure cavity upper cover and a lower bearing plate; 2) placing various sensors in the telescopic steel sleeve; 3) arranging a sealing aluminium sheet on an outburst opening sealing taper sleeve, and screwing a sealing screw plug in the upper end of the confining pressure cavity upper cover; 4) monitoring variations of stresses, temperatures and gas pressures of the raw coal test specimen before and after tests; 5) pressurizing the test specimen in a main pressure chamber, and increasing the axial pressure and confining pressure to the predetermined loads; 6) evacuating air inside a rubber sleeve of the main pressure chamber; 7) filling gases into the raw coal test specimen; and 8) piercing the sealing aluminium sheet to generate outburst, and carrying out real-time monitoring and gathering on various data. By adopting the method, raw coal in different sizes can be adopted to carry out coal and gas outburst tests in the triaxial stress state to study the coal and gas outburst occurrence principles more comprehensively and scientifically.
Description
Technical field
The present invention relates to a kind of coal and gas prominent multi-parameter monitoring method, particularly relate to a kind of multi-scenarios method Coal Under and Gas Outburst multi-parameter monitoring method.
Background technology
Coal and gas prominent is a kind of extremely complicated dynamic phenomenon of underground coal mine, and it seriously threatens Safety of Coal Mine Production, affects the performance of coal production ability.At driving face, particularly often coal and non-coal postponing bursting occurs in stone door punching coal process, it is the coal and gas prominent that after explosion or operation, a period of time inherent explosion or operation place occur.Steeply pitching seam etc. first time outstanding occur after also once occurred secondary outstanding or even three times outstanding.According to incompletely statistics; there is a few percent that postponing bursting number of times accounts for total outstanding number of times in the whole nation; although proportion is little; but because " extension ", this kind of giving prominence to often exceeds the unexpected of people, the defer time of postponing bursting; without certain rule; short then a few minutes, long then tens hours, even several days; Secondary is given prominence to and is also often occurred in the scale removal process after giving prominence to for the first time; If outstanding time, just in time run into workplace have people to carry out operation or outstanding to last time after clearing up, personnel can not withdraw in time, very harmful to miner, and cause great casualties and property loss, mine safety production in serious threat.The mechanism that coal and gas prominent occurs and form are complicated, along with the increase of coal mining depth and mining conditions day by day complicated, the generation of coal and gas prominent is also difficult to prediction more, at present, the study mechanism of Chinese scholars to coal and gas prominent makes certain gains, but most achievement is all the hypothesis that field statistics data and laboratory study propose.These hypothesis all can only be described a part of phenomenon of certain of coal and gas prominent, can't form the complete Principle System of quantification.Utilize existing hypothesis to predict very large difficulty to coal and gas prominent, and accuracy is not high, this just brings huge hidden danger to mine safety production.
At present, mainly there is following problem in the device carrying out coal and gas prominent test: the test specimen that (1) adopts mostly is moulded coal, although moulded coal has similarity with raw coal to a certain extent, still there is larger difference in both, and the research to coal and gas prominent mechanism has certain limitation; (2) part moulded coal sample dimensions is comparatively large, and the test preparatory period is longer; (3) device is installed comparatively complicated; (4) device can only produce and once give prominence to, and can not reflect down-hole coal and gas prominent phenomenon really; (5) aspis opening speed is comparatively slow, have impact on the time of coal and gas prominent to a certain extent, can not close to field condition.
Summary of the invention
For above shortcomings in prior art, the invention provides a kind of multi-scenarios method Coal Under and Gas Outburst multi-parameter monitoring method.The method can adopt the raw coal of different size to carry out coal and gas prominent test under triaxial stress state, and the mechanism occurred coal and gas prominent is carried out more comprehensively, more scientific research.
In order to solve the problems of the technologies described above, present invention employs following technical scheme:
Multi-scenarios method Coal Under and Gas Outburst multi-parameter monitoring method, in this monitoring method, have employed a kind of main pressure chamber, this main pressure chamber comprises confined pressure room base, steel cylinder, confined pressure chamber upper cover, aspis seal taper sleeve, sealing aluminium flake, sealing plug, elevating screw, load sensor, lower bearing plate and confined pressure piston; Described steel cylinder is placed on the base of confined pressure room, arranges confined pressure O-ring seal between described confined pressure chamber upper cover and steel cylinder, and confined pressure chamber upper cover is pressed on steel cylinder by pull bar; Described lower bearing plate to be arranged in steel cylinder and to be slidably matched with the inwall of steel cylinder, described elevating screw is vertically arranged on the below of lower bearing plate and withstands on lower bearing plate by load sensor, the tapered structure in top of described lower bearing plate, described confined pressure piston bush is on the top of lower bearing plate and be sealed and matched with lower bearing plate, and described confined pressure piston coordinates with the inner wall sealing of steel cylinder; The middle part of described confined pressure chamber upper cover is large conical hollow structure suitable for reading, is sealed and matched in the bell that described aspis seal taper sleeve is pressed in confined pressure chamber upper cover with confined pressure chamber upper cover;
This monitoring method comprises the steps:
1) the raw coal test specimen that diameter is 50 ~ 100mm is extracted, raw coal test specimen to be contained in flexible steel bushing and to be fixed by flexible steel bushing, flexible steel bushing is arranged between confined pressure chamber upper cover in main pressure chamber and lower bearing plate, then is enclosed within gum cover that flexible steel bushing is outer to be sealed raw coal test specimen;
2) laying temperature sensor, pressure transducer, shaft position sensor and radial extensometer in flexible steel bushing;
3) described sealing aluminium flake is arranged on aspis seal taper sleeve, and described sealing plug to screw in the upper port of confined pressure chamber upper cover and is pressed on sealing aluminium flake, and sealing aluminium flake and aspis seal taper sleeve are sealed and matched;
4) start Data Control and acquisition system, the change of the stress of raw coal test specimen, temperature and gaseous tension before and after monitoring test, and it is gathered;
5) the raw coal test specimen in main pressure chamber is pressurizeed, to water filling between flexible steel bushing and steel cylinder, confined pressure is applied to the raw coal test specimen in flexible steel bushing; By elevating screw, axial compression is applied to the raw coal test specimen in flexible steel bushing;
6) carrying out emptying to the air of main pressure chamber's gum cover inside, taking out the air of main pressure chamber's gum cover inside with vacuum pump when keeping axial compression and confined pressure is constant, until gaseous tension is lower than 10Pa;
7) when keeping axial compression and confined pressure is constant, being filled with methane gas to raw coal test specimen, making the adsorbed gas of raw coal test specimen reach equilibrium state, be filled with methane gas and must ensure more than 48h;
8) after everything in readiness, puncture sealing aluminium flake, the raw coal test specimen in gum cover and methane gas produce outstanding; Real-Time Monitoring and collection are carried out to each data in whole experimentation.
Compared with prior art, multi-scenarios method Coal Under of the present invention and Gas Outburst multi-parameter monitoring method tool have the following advantages:
1, the method can adopt the raw coal of different size to carry out coal and gas prominent test under triaxial stress state, and the mechanism occurred coal and gas prominent is carried out more comprehensively, more scientific research.
2, the method can monitor the gas pressure of raw coal body in outstanding front and back, stress-strain state and temperature variations, to reach the target being familiar with coal and gas prominent mechanism under various factors effect; Because adopt raw coal to test in test, result more tallies with the actual situation, and can better disclose the effect of various factors.
3, the method can be familiar with the destruction of outstanding process to coal body, provides support for layering soft in coal seam and outstanding coal study on the genesis; For the degree of impairment of coal body under outstanding role and the research of micro-damage state provide basis.So that the mechanism that more scientific research coal and gas prominent produces, that form science, perfect theory, for the control of colliery to coal and gas prominent is provided fundamental basis.
Accompanying drawing explanation
Fig. 1 is the structural representation of main pressure chamber;
Fig. 2 is the structural representation of main pressure chamber's top seal;
Fig. 3 is the structural representation of main pressure chamber's lower seal.
In accompanying drawing: 1-elevating screw; 2-load sensor; 3-gas inlet pipe; 4-lower bearing plate; 5-confined pressure piston; 6-confined pressure O-ring seal; 7-cable sealed joint; 8-radial extensometer; 9-flexible steel bushing; 10-built-in foil gauge; 11-gum cover; 12-aspis seal taper sleeve; 13-O-ring seal; 14-sealing aluminium flake; 15-sealing plug; 16-aspis baroceptor; 17-vent valve; 18-confined pressure chamber upper cover; 19-confined pressure O-ring seal; 20-steel cylinder; 21-protection network; 22-pull bar; 23-pressing plate is installed; 24-confined pressure room base; 25-confined pressure penstocks; 26-vacuumize tracheae; 27-gas air intake duct; 28-press water inlet channel.
Embodiment
Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail.
Multi-scenarios method Coal Under and Gas Outburst multi-parameter monitoring method, have employed a kind of main pressure chamber in this monitoring method.
As shown in Figure 1,2 and 3, this main pressure chamber comprises confined pressure room base 24, steel cylinder 20, confined pressure chamber upper cover 18, aspis seal taper sleeve 12, sealing aluminium flake 14, sealing plug 15, elevating screw 1, load sensor 2, lower bearing plate 4 and confined pressure piston 5 to the structure of main pressure chamber.Confined pressure room base 24 is arranged in frame by installing pressing plate 23, steel cylinder 20 is placed on confined pressure room base 24, arrange confined pressure O-ring seal 19 between confined pressure chamber upper cover 18 and steel cylinder 20, confined pressure chamber upper cover 18 is pressed on steel cylinder 20 by pull bar 22, arranges one deck protection network 21 outside steel cylinder 20.Lower bearing plate 4 to be arranged in steel cylinder 20 and to be slidably matched with the inwall of steel cylinder 20, elevating screw 1 is vertically arranged on the below of lower bearing plate 4 and withstands on lower bearing plate 4 by load sensor 2, the tapered structure in top of lower bearing plate 4, confined pressure piston 5 is enclosed within the top of lower bearing plate 4 and is sealed and matched by gum cover 11 and lower bearing plate 4, and the outer wall of confined pressure piston 5 is coordinated with the inner wall sealing of steel cylinder 20 by confined pressure O-ring seal 6.The middle part of confined pressure chamber upper cover 18 is large conical hollow structure suitable for reading, is sealed and matched in the bell that aspis seal taper sleeve 12 is pressed in confined pressure chamber upper cover 18, confined pressure chamber upper cover 18 is provided with vent valve 17 by gum cover 11 and confined pressure chamber upper cover 18.Be provided with gas air intake duct 27 at the middle part of confined pressure piston 5 and lower bearing plate 4 and vacuumize air flue, gas air intake duct 27 is connected with gas inlet pipe 3, vacuumize air flue and vacuumize tracheae 26 and be connected, confined pressure piston 5 and lower bearing plate 4 keep to the side and be provided with press water inlet channel 28, and press water inlet channel 28 is connected with confined pressure penstocks 25.
This multi-scenarios method Coal Under and Gas Outburst multi-parameter monitoring method, comprise the steps:
1) the raw coal test specimen that diameter is 50 ~ 100mm is extracted, raw coal test specimen to be contained in flexible steel bushing 9 and to be fixed by flexible steel bushing 9, flexible steel bushing 9 is arranged between confined pressure chamber upper cover 18 in main pressure chamber and lower bearing plate 4, then is enclosed within flexible steel bushing 9 with gum cover 11 and is sealed by raw coal test specimen outward.Make gas air intake duct 27 and vacuumize air flue to communicate with raw coal test specimen, in the present embodiment, vacuumize air flue and be communicated with gas air intake duct 27.Make to form confined pressure chamber between gum cover 11 and steel cylinder 20, confined pressure chamber communicates with press water inlet channel 28, and vent valve 17 communicates with in confined pressure chamber.
2) in flexible steel bushing 9, laying temperature sensor, pressure transducer, built-in foil gauge 10(comprise shaft position sensor and radial extensometer 8), complete the connection of various lead-in wire.The lead-in wire of radial extensometer 8 is connected with the cable splice on confined pressure piston 5 by cable sealed joint 7.
3) sealing aluminium flake 14 is arranged on aspis seal taper sleeve 12, and sealing plug 15 to screw in the upper port of confined pressure chamber upper cover 18 and is pressed on sealing aluminium flake 14, and sealing aluminium flake 14 is sealed and matched by O-ring seal 13 and aspis seal taper sleeve 12.Endoporus near aspis seal taper sleeve 12 is provided with aspis baroceptor 16.
4) start Data Control and acquisition system, the change of the stress of raw coal test specimen, temperature and gaseous tension before and after monitoring test, and it is gathered.
5) the raw coal test specimen in main pressure chamber is pressurizeed, by confined pressure penstocks 25 and press water inlet channel 28 to water filling in the confined pressure chamber between flexible steel bushing 9 and steel cylinder 20, confined pressure is applied to the raw coal test specimen in flexible steel bushing 9; By elevating screw 1, axial compression is applied to the raw coal test specimen in flexible steel bushing 9, axial compression and confined pressure are added to predetermined load.
6) carry out emptying to the air of main pressure chamber's gum cover 11 inside, when keeping axial compression and confined pressure constant with vacuum pump by vacuumizing tracheae 26 and vacuumizing the air that air flue takes out main pressure chamber's gum cover 11 inside, until gaseous tension is lower than 10Pa.
7) when keeping axial compression and confined pressure is constant, being filled with methane gas by gas inlet pipe 3 and gas air intake duct 27 to raw coal test specimen, making the adsorbed gas of raw coal test specimen reach equilibrium state, be filled with methane gas and must ensure more than 48h.
8) after everything in readiness, puncture sealing aluminium flake 14, the raw coal test specimen in gum cover 11 and methane gas produce outstanding; Real-Time Monitoring and collection are carried out to each data in whole experimentation.
What finally illustrate is, above embodiment is only in order to illustrate technical scheme of the present invention and unrestricted, although with reference to preferred embodiment to invention has been detailed description, those of ordinary skill in the art is to be understood that, can modify to technical scheme of the present invention or equivalent replacement, and not departing from aim and the scope of technical solution of the present invention, it all should be encompassed in the middle of right of the present invention.
Claims (1)
1. multi-scenarios method Coal Under and Gas Outburst multi-parameter monitoring method, it is characterized in that, in this monitoring method, have employed a kind of main pressure chamber, this main pressure chamber comprises confined pressure room base (24), steel cylinder (20), confined pressure chamber upper cover (18), aspis seal taper sleeve (12), sealing aluminium flake (14), sealing plug (15), elevating screw (1), load sensor (2), lower bearing plate (4) and confined pressure piston (5); Described steel cylinder (20) is placed on confined pressure room base (24), arranges confined pressure O-ring seal (19) between described confined pressure chamber upper cover (18) and steel cylinder (20), and confined pressure chamber upper cover (18) is pressed on steel cylinder (20) by pull bar (22); Described lower bearing plate (4) to be arranged in steel cylinder (20) and to be slidably matched with the inwall of steel cylinder (20), described elevating screw (1) is vertically arranged on the below of lower bearing plate (4) and withstands on lower bearing plate (4) by load sensor (2), the tapered structure in top of described lower bearing plate (4), described confined pressure piston (5) is enclosed within the top of lower bearing plate (4) and is sealed and matched with lower bearing plate (4), and described confined pressure piston (5) coordinates with the inner wall sealing of steel cylinder (20); The middle part of described confined pressure chamber upper cover (18) is large conical hollow structure suitable for reading, is sealed and matched in the bell that described aspis seal taper sleeve (12) is pressed in confined pressure chamber upper cover (18) with confined pressure chamber upper cover (18);
This monitoring method comprises the steps:
1) the raw coal test specimen that diameter is 50 ~ 100mm is extracted, raw coal test specimen is contained in flexible steel bushing (9) interior and fixing by flexible steel bushing (9), flexible steel bushing (9) is arranged between confined pressure chamber upper cover (18) in main pressure chamber and lower bearing plate (4), then uses gum cover (11) to be enclosed within flexible steel bushing (9) to be sealed by raw coal test specimen outward;
2) laying temperature sensor, pressure transducer, shaft position sensor and radial extensometer (8) in flexible steel bushing (9);
3) described sealing aluminium flake (14) is arranged on aspis seal taper sleeve (12), described sealing plug (15) to screw in the upper port in confined pressure chamber upper cover (18) and is pressed in sealing aluminium flake (14), and sealing aluminium flake (14) and aspis seal taper sleeve (12) are sealed and matched;
4) start Data Control and acquisition system, the change of the stress of raw coal test specimen, temperature and gaseous tension before and after monitoring test, and it is gathered;
5) the raw coal test specimen in main pressure chamber is pressurizeed, to water filling between flexible steel bushing (9) and steel cylinder (20), confined pressure is applied to the raw coal test specimen in flexible steel bushing (9); By elevating screw (1), axial compression is applied to the raw coal test specimen in flexible steel bushing (9);
6) inner to main pressure chamber's gum cover (11) air carries out emptying, takes out the inner air of main pressure chamber's gum cover (11), until gaseous tension is lower than 10Pa when keeping axial compression and confined pressure is constant with vacuum pump;
7) when keeping axial compression and confined pressure is constant, being filled with methane gas to raw coal test specimen, making the adsorbed gas of raw coal test specimen reach equilibrium state, be filled with methane gas and must ensure more than 48h;
8) after everything in readiness, puncture sealing aluminium flake (14), the raw coal test specimen in gum cover (11) and methane gas produce outstanding; Real-Time Monitoring and collection are carried out to each data in whole experimentation.
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| CN104007250A (en) * | 2014-06-17 | 2014-08-27 | 重庆大学 | Visual tri-axial seepage device |
| CN108205054A (en) * | 2018-01-29 | 2018-06-26 | 西安科技大学 | Destructive characteristics experimental provision of the coal cinder containing high pressure gas in the unexpected release of ambient atmos |
| CN110618072A (en) * | 2019-09-06 | 2019-12-27 | 河南工程学院 | Coal body crack monitoring-gas permeation experimental device |
| CN114352268B (en) * | 2022-01-14 | 2023-06-02 | 河南理工大学 | Device and method for testing gas pressure of water-containing surrounding rock coal seam |
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| SU1167357A2 (en) * | 1984-04-19 | 1985-07-15 | Институт проблем комплексного освоения недр АН СССР | Apparatus for simulating spontaneous outbursts |
| CN101226183B (en) * | 2008-01-22 | 2011-09-07 | 重庆大学 | Projecting simulator stand for coal and firedamp |
| CN201170782Y (en) * | 2008-01-22 | 2008-12-24 | 重庆大学 | Quick releasing mechanism for projecting simulator stand of coal and mash gas |
| CN201285392Y (en) * | 2008-11-14 | 2009-08-05 | 重庆大学 | Mold for coal and firedamp projecting simulator experiment |
| CN101487834B (en) * | 2009-02-06 | 2012-03-28 | 煤炭科学研究总院重庆研究院 | Combined test apparatus for coal and gas burst |
| CN101487835B (en) * | 2009-02-06 | 2013-06-05 | 煤炭科学研究总院重庆研究院 | Test apparatus for coal and gas burst |
| CN101806792B (en) * | 2010-04-15 | 2013-06-05 | 中国科学院力学研究所 | Coal and gas outburst simulation test device and protection device thereof |
| CN102095835B (en) * | 2011-01-19 | 2014-05-28 | 河南理工大学 | Device for simulating coal and gas outburst experiment |
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