CN205449758U - Outlet pressure adjustable coal petrography seepage flow experimental system - Google Patents
Outlet pressure adjustable coal petrography seepage flow experimental system Download PDFInfo
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- CN205449758U CN205449758U CN201620266597.9U CN201620266597U CN205449758U CN 205449758 U CN205449758 U CN 205449758U CN 201620266597 U CN201620266597 U CN 201620266597U CN 205449758 U CN205449758 U CN 205449758U
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Abstract
The utility model provides an outlet pressure adjustable coal petrography seepage flow experimental system, includes methane gas pitcher, confined pressure loading pump, axle load loading pump, first three -way valve, second three -way valve, third three -way valve, coal sample holder, display, pressure tracker and computer, the methane gas pitcher is connected with the air inlet of coal sample holder through the second trachea through the access connection of first trachea with first three -way valve, one of them export of first three -way valve, and the gas outlet of coal sample holder is passed through the third trachea and is connected with the air inlet of pressure tracker, another exit sealing connection of first three -way valve has a pressure sensor, be equipped with the relief pressure valve on the first trachea, be equipped with mass flow meter on the third trachea, the utility model discloses the process is simple, convenient operation, utilize this method when going on testing than high pressure seepage flow reducible inlet end with to give vent to anger the end pressure poor, reduction model error, electronic technology collection experiment parameter is all utilized to this method, and the experiment parameter precision of acquireing is high, and observation error reduces greatly.
Description
Technical field
This utility model relates to a kind of outlet pressure adjustable coal petrography seepage flow experiment system.
Background technology
In the field such as coal bed gas, natural gas, Permeability Oe Coal And Porous Rock And Fractured Rock is extremely important technical parameter, it is related to coal seam reservoirs extraction value and yield is estimated, but owing to Permeability Oe Coal And Porous Rock And Fractured Rock is affected by many factors, such as stress, the absorption of gas, temperature, the disturbance etc. of extraction engineering, the measurement making Permeability Oe Coal And Porous Rock And Fractured Rock is the most difficult, and the permeability the most accurately measuring coal petrography is significant.
At present, the method for laboratory test coal sample permeability is mainly filled with certain pressure gas at the i.e. inlet end in held coal petrography sample one end, gathers infiltration capacity in the i.e. outlet side of the other end of coal petrography sample, calculates permeability by Darcy's law；Expert adopts and achieves substantial amounts of achievement in research in this way before, and engineering practice has carried out certain guidance, but there is following two defect:
(1) the conventional measurement port of export to coal petrography gas permeability is atmospheric pressure, but during carrying out the extraction of coal bed gas and natural gas, extraction end is in subnormal ambient, and seepage exit end is negative pressure state, traditional port of export is atmospheric pressure, subnormal ambient during extraction can not be simulated well, inconsistent with practical situation；
(2) coal petrography is one of principal element affecting permeability on the adsorption of gas, and when carrying out permeability test, owing to coal petrography sample is under certain barometric gradient, adsorptive pressure often uses average adsorption pressure instead:, in formula, p is adsorptive pressure,For outlet side pressure i.e. atmospheric pressure,For inlet end pressure, changing adsorptive pressure is by regulation inlet endRealize for inlet end pressure, but the pressure reduction of inlet end and outlet side is the biggest, replace error produced by adsorptive pressure the biggest with average adsorption pressure, and when two ends pressure reduction is bigger, seepage discharge increases, the error gathering gas flow also can increase, and thus records permeability and there is bigger error；
(3) gas pressure loaded and axial compression, confined pressure present stage are all artificially to be read by manometric registration, it is thus achieved that pressure parameter error bigger.
Utility model content
This utility model is in order to solve weak point of the prior art, it is provided that a kind of simple in construction, easy to operate, by the regulation of outlet pressure realizes a kind of outlet pressure adjustable coal petrography seepage flow experiment system of the Seepage Experiment when negative pressure or malleation, different adsorptive pressure.
For solving above-mentioned technical problem, this utility model adopts the following technical scheme that a kind of outlet pressure adjustable coal petrography seepage flow experiment system, including methane gas tank, confined pressure load pump, axial compression load pump, the first three-way valve, the second three-way valve, the 3rd three-way valve, coal sample clamper, display, pressure tracking instrument and computer；Methane gas tank is connected by the import of the first trachea and the first three-way valve, and one of them outlet of the first three-way valve is connected by the air inlet of the second trachea with coal sample clamper, and the gas outlet of coal sample clamper is connected with the air inlet of pressure tracking instrument by the 3rd trachea；Another exit of first three-way valve is sealedly connected with the first pressure transducer；First trachea is provided with air relief valve, and the 3rd trachea is provided with mass flowmenter；
Coal sample clamper is provided with confined pressure loading interface and axial compression loading interface, the confined pressure loading interface of coal sample clamper is connected by one of them outlet of the 4th trachea and the second three-way valve, the import of the second three-way valve loads delivery side of pump by confined pressure compression tube with confined pressure and is connected, and another exit of the second three-way valve is sealedly connected with the second pressure transducer；The axial compression loading interface of coal sample clamper is connected by one of them outlet of the 5th trachea and the 3rd three-way valve, the import of the 3rd three-way valve loads delivery side of pump by axial compression compression tube with axial compression and is connected, and another exit of the 3rd three-way valve is sealedly connected with the 3rd pressure transducer；
Display is built-in with display controller, and display controller is connected by data wire and the first pressure transducer, the second pressure transducer and the 3rd pressure transducer respectively；Computer is connected with mass flowmenter and pressure tracking instrument by data wire respectively.
Pressure tracking instrument includes PLC, telescopic oil cylinder, sealing surge-chamber and control box, seal surge-chamber and be fixed on control box top, seal surge-chamber bottom uncovered and with control box inner space, seal surge-chamber top and be provided with pressure regulation air inlet and pressure regulation gas outlet, pressure regulation air inlet is connected with the gas outlet of coal sample clamper by the 3rd trachea, pressure regulation gas outlet is in communication with the outside by the 6th trachea, and the 6th trachea is provided with pneumatic operated valve, seals surge-chamber roof and is provided with the 4th pressure transducer；The cylinder ends of telescopic oil cylinder is fixed on the bottom in control box, and the piston rod of telescopic oil cylinder is fixed with connecting rod vertically upward, and connecting rod top is provided with piston, and piston is positioned at sealing surge-chamber and piston outer rim and is connected with sealing the slipper seal of surge-chamber medial wall；PLC is arranged in control box, and control box top right side is provided with guidance panel, and PLC is connected with telescopic oil cylinder, the 4th pressure transducer, guidance panel and computer by data wire respectively.
The experimental technique of a kind of outlet pressure adjustable coal petrography seepage flow experiment system, comprises the following steps:
(1) coal sample that cross-sectional area is a is seated in coal sample clamper, then all valves on the first three-way valve, the second three-way valve and the 3rd three-way valve and pneumatic operated valve are opened, by axial compression load pump, coal sample loaded axial compression, and by confined pressure load pump, coal sample is loaded confined pressure；
(2) open pneumatic operated valve, guidance panel inputs set target pressureIf, goal pressureFor negative pressure, instruction is sent to PLC by operation guidance panel, PLC starts telescopic oil cylinder after receiving instruction, the piston rod of telescopic oil cylinder upwardly connecting rod, until the piston of the connecting rod other end reaches to seal the top of surge-chamber, close pneumatic operated valve, then control telescopic oil cylinder by guidance panel and PLC, telescopic oil cylinder pulls downward on connecting rod, when PLC reaches the goal pressure of setting by the 4th pressure sensor monitoring to pressureAfter, the instruction of stopping action being sent to telescopic oil cylinder；
If goal pressureFor malleation, instruction is sent to PLC by operation guidance panel, PLC starts telescopic oil cylinder after receiving instruction, the piston rod of telescopic oil cylinder pulls downward on connecting rod, until the piston of the connecting rod other end reaches to seal the bottom of surge-chamber, close pneumatic operated valve, then control telescopic oil cylinder by guidance panel and PLC, telescopic oil cylinder upwardly connecting rod, when PLC reaches the goal pressure of setting by the 4th pressure sensor monitoring to pressureAfter, the instruction of stopping action being sent to telescopic oil cylinder；
(3) methane gas tank and air relief valve are opened, gas in methane gas tank enters in coal sample clamper along the first trachea and the second trachea, and then gas after seepage flow enter the 3rd tracheal strips from the gas outlet of coal sample clamper, then, in gas enters into sealing surge-chamber, simultaneous computer starts the flow of recording quality effusion meter；
(4) after the stability of flow of mass flowmenter, the force value on the first pressure transducer is read over the display, draw the average discharge Q of mass flowmenter after stably the most on computers；
(5) permeability of coal sample is calculated。
Use technique scheme, this utility model have the advantages that this utility model can consider infiltration gas absorption analytic function Imitating extraction time subnormal ambient, closer to on-site actual situations, the impact of the factors such as different stress state, different stress paths can be considered again simultaneously；Utilize the subnormal ambient that pressure tracking instrument produces, it is possible to individually carrying out the coal petrography absorption correlational study such as analytic properties and transformation parsing under subnormal ambient, experimental system can realize variation research；Especially pressure tracking instrument can make the internal subnormal ambient producing steady pressure of device, and this is the function not available for most experiments system.
In sum, this utility model process is simple, easy to operate, utilizes the method can reduce inlet end and outlet side pressure reduction when carrying out elevated pressures Seepage Experiment, reduces model error；The method all utilizes electronic technology to gather experiment parameter, and the experiment parameter precision of acquisition is high, and observation error is greatly reduced.
Accompanying drawing explanation
Fig. 1 is structural representation of the present utility model；
Fig. 2 is the structural representation of pressure tracking instrument in Fig. 1.
Detailed description of the invention
As shown in Figure 1-2, a kind of outlet pressure adjustable coal petrography seepage flow experiment system of the present utility model, including methane gas tank 1, confined pressure load pump 17, axial compression load pump the 21, first three-way valve the 2, second three-way valve the 3, the 3rd three-way valve 4, coal sample clamper 5, display 6, pressure tracking instrument 7 and computer 8；Methane gas tank 1 is connected with the air inlet of the first three-way valve 2 by the first trachea 9, one of them outlet of first three-way valve 2 is connected with the air inlet of coal sample clamper 5 by the second trachea 10, and the gas outlet of coal sample clamper 5 is connected with the air inlet of pressure tracking instrument 7 by the 3rd trachea 11；Another exit of first three-way valve 2 is sealedly connected with the first pressure transducer 12；First trachea 9 is provided with air relief valve 13, and the 3rd trachea 11 is provided with mass flowmenter 14；
Coal sample clamper 5 is provided with confined pressure loading interface and axial compression loading interface, the confined pressure loading interface of coal sample clamper 5 is connected with one of them outlet of the second three-way valve 3 by the 4th trachea 15, the import of the second three-way valve 3 is connected with the outlet of confined pressure load pump 17 by confined pressure compression tube 16, and another exit of the second three-way valve 3 is sealedly connected with the second pressure transducer 18；The axial compression loading interface of coal sample clamper 5 is connected with one of them outlet of the 3rd three-way valve 4 by the 5th trachea 19, the import of the 3rd three-way valve 4 is connected with the outlet of axial compression load pump 21 by axial compression compression tube 20, and another exit of the 3rd three-way valve 4 is sealedly connected with the 3rd pressure transducer 22；
Display 6 is built-in with display controller 61, and display controller 61 is connected with first pressure transducer the 12, second pressure transducer 18 and the 3rd pressure transducer 22 by data wire respectively；Computer 8 is connected with mass flowmenter 14 and pressure tracking instrument 7 by data wire respectively.
Pressure tracking instrument 7 includes PLC 23, telescopic oil cylinder 24, seals surge-chamber 25 and control box 26, seal surge-chamber 25 and be fixed on control box 26 top, seal surge-chamber 25 bottom uncovered and with control box 26 inner space, seal surge-chamber 25 top and be provided with pressure regulation air inlet 27 and pressure regulation gas outlet 28, pressure regulation air inlet 27 is connected with the gas outlet of coal sample clamper 5 by the 3rd trachea 11, pressure regulation gas outlet 28 is in communication with the outside by the 6th trachea 29,6th trachea 29 is provided with pneumatic operated valve 30, seals surge-chamber 25 inside top and is provided with the 4th pressure transducer 31；The cylinder ends of telescopic oil cylinder 24 is fixed on the bottom in control box 26, the piston rod of telescopic oil cylinder 24 is fixed with connecting rod 32 vertically upward, connecting rod 32 top is provided with piston 33, and piston 33 is positioned at sealing surge-chamber 25 and piston 33 outer rim and is connected with sealing surge-chamber 25 inwall slipper seal；PLC 23 is arranged on control box 26 inner right side, and control box 26 top right side is provided with guidance panel 34, and PLC 23 is connected with telescopic oil cylinder the 24, the 4th pressure transducer 31, guidance panel 34 and computer 8 by data wire respectively.
Guidance panel 34, PLC 23, mass flowmenter 14, computer 8, display 6 and display controller 61 are routine techniques, and its concrete structure no longer describes in detail.
The experimental technique of a kind of outlet pressure adjustable coal petrography seepage flow experiment system, comprises the following steps:
(1) coal sample that cross-sectional area is a is seated in coal sample clamper 5, then all valves on first three-way valve the 2, second three-way valve 3 and the 3rd three-way valve 4 and pneumatic operated valve 30 are opened, by axial compression load pump 21 to coal sample loading axial compression, and by confined pressure load pump 17, coal sample is loaded confined pressure；
(2) open pneumatic operated valve 30, guidance panel 34 inputs set target pressureIf, goal pressureFor negative pressure, instruction is sent to PLC 23 by operation guidance panel 34, PLC starts telescopic oil cylinder 24 after receiving instruction, the piston rod of telescopic oil cylinder 24 upwardly connecting rod 32, until the piston 33 of connecting rod 32 other end reaches to seal the top of surge-chamber 25, close pneumatic operated valve 30, then telescopic oil cylinder 24 is controlled by guidance panel 34 and PLC 23, telescopic oil cylinder 24 pulls downward on connecting rod 32, when PLC 23 monitors, by the 4th pressure transducer 31, the goal pressure that pressure reaches to setAfter, the instruction of stopping action being sent to telescopic oil cylinder 24；
If goal pressureFor malleation, instruction is sent to PLC 23 by operation guidance panel 34, PLC 23 starts telescopic oil cylinder 24 after receiving instruction, the piston rod of telescopic oil cylinder 24 pulls downward on connecting rod 32, until the piston 33 of connecting rod 32 other end reaches to seal the bottom of surge-chamber 25, close pneumatic operated valve 30, then telescopic oil cylinder 24 is controlled by guidance panel 34 and PLC 23, telescopic oil cylinder 24 upwardly connecting rod 32, arrive, when PLC monitors pressure by the 4th pressure transducer 31, the goal pressure setAfter, the instruction of stopping action being sent to telescopic oil cylinder 24；
(3) methane gas tank 1 and air relief valve 13 are opened, gas in methane gas tank 1 enters in coal sample clamper 5 along the first trachea 9 and the second trachea 10, and then gas after seepage flow enter in the 3rd trachea 11 from the gas outlet of coal sample clamper 5, then, in gas enters into sealing surge-chamber 25, simultaneous computer 8 starts the flow of recording quality effusion meter 14；
(4) after the stability of flow of mass flowmenter 14, the force value on the first pressure transducer 12 is read on the display 6, on computer 8, then draw the average discharge Q of mass flowmenter 14 after stably；
(5) permeability of coal sample is calculated;Wherein, k is coal sample permeability, unit mD；μ is gas viscosity, unit 10-6pa·s；L is specimen length, unit cm；p0For atmospheric pressure, units MPa；Q is average discharge, unit cm3/s；A is coal sample floor space, unit cm2；p1、p2It is respectively inlet end and outlet side pressure, unit Mpa.
Shape of the present utility model, material, structure etc. are not made any pro forma restriction by the present embodiment; every any simple modification, equivalent variations and modification made above example according to technical spirit of the present utility model, belongs to the protection domain of technical solutions of the utility model.
Claims (2)
1. an outlet pressure adjustable coal petrography seepage flow experiment system, it is characterised in that: include methane gas tank, confined pressure load pump, axial compression load pump, the first three-way valve, the second three-way valve, the 3rd three-way valve, coal sample clamper, display, pressure tracking instrument and computer；Methane gas tank is connected by the import of the first trachea and the first three-way valve, and one of them outlet of the first three-way valve is connected by the air inlet of the second trachea with coal sample clamper, and the gas outlet of coal sample clamper is connected with the air inlet of pressure tracking instrument by the 3rd trachea；Another exit of first three-way valve is sealedly connected with the first pressure transducer；First trachea is provided with air relief valve, and the 3rd trachea is provided with mass flowmenter；
Coal sample clamper is provided with confined pressure loading interface and axial compression loading interface, the confined pressure loading interface of coal sample clamper is connected by one of them outlet of the 4th trachea and the second three-way valve, the import of the second three-way valve loads delivery side of pump by confined pressure compression tube with confined pressure and is connected, and another exit of the second three-way valve is sealedly connected with the second pressure transducer；The axial compression loading interface of coal sample clamper is connected by one of them outlet of the 5th trachea and the 3rd three-way valve, the import of the 3rd three-way valve loads delivery side of pump by axial compression compression tube with axial compression and is connected, and another exit of the 3rd three-way valve is sealedly connected with the 3rd pressure transducer；
Display is built-in with display controller, and display controller is connected by data wire and the first pressure transducer, the second pressure transducer and the 3rd pressure transducer respectively；Computer is connected with mass flowmenter and pressure tracking instrument by data wire respectively.
A kind of outlet pressure adjustable coal petrography seepage flow experiment system the most according to claim 1, it is characterized in that: pressure tracking instrument includes PLC, telescopic oil cylinder, seal surge-chamber and control box, seal surge-chamber and be fixed on control box top, seal surge-chamber bottom uncovered and with control box inner space, seal surge-chamber top and be provided with pressure regulation air inlet and pressure regulation gas outlet, pressure regulation air inlet is connected with the gas outlet of coal sample clamper by the 3rd trachea, pressure regulation gas outlet is in communication with the outside by the 6th trachea, 6th trachea is provided with pneumatic operated valve, seal surge-chamber roof and be provided with the 4th pressure transducer；The cylinder ends of telescopic oil cylinder is fixed on the bottom in control box, and the piston rod of telescopic oil cylinder is fixed with connecting rod vertically upward, and connecting rod top is provided with piston, and piston is positioned at sealing surge-chamber and piston outer rim and is connected with sealing the slipper seal of surge-chamber medial wall；PLC is arranged in control box, and control box top right side is provided with guidance panel, and PLC is connected with telescopic oil cylinder, the 4th pressure transducer, guidance panel and computer by data wire respectively.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201620266597.9U CN205449758U (en) | 2016-04-01 | 2016-04-01 | Outlet pressure adjustable coal petrography seepage flow experimental system |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201620266597.9U CN205449758U (en) | 2016-04-01 | 2016-04-01 | Outlet pressure adjustable coal petrography seepage flow experimental system |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105717026A (en) * | 2016-04-01 | 2016-06-29 | 河南理工大学 | Coal rock permeability experiment system with adjustable outlet pressure as well as method |
| CN106644823A (en) * | 2016-12-21 | 2017-05-10 | 山西大学 | Air tightness testing device for coal wall coating and air tightness testing method applied to air tightness testing device |
| CN107907466A (en) * | 2017-12-01 | 2018-04-13 | 贵州大学 | It is a kind of to change gas humidity and three axis seepage apparatus of port of export positive pressure |
| CN108760597A (en) * | 2018-04-11 | 2018-11-06 | 河南理工大学 | A kind of experimental method of evaluation coal seam reservoirs voltage-sensitive effect |
-
2016
- 2016-04-01 CN CN201620266597.9U patent/CN205449758U/en not_active Withdrawn - After Issue
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105717026A (en) * | 2016-04-01 | 2016-06-29 | 河南理工大学 | Coal rock permeability experiment system with adjustable outlet pressure as well as method |
| CN106644823A (en) * | 2016-12-21 | 2017-05-10 | 山西大学 | Air tightness testing device for coal wall coating and air tightness testing method applied to air tightness testing device |
| CN107907466A (en) * | 2017-12-01 | 2018-04-13 | 贵州大学 | It is a kind of to change gas humidity and three axis seepage apparatus of port of export positive pressure |
| CN108760597A (en) * | 2018-04-11 | 2018-11-06 | 河南理工大学 | A kind of experimental method of evaluation coal seam reservoirs voltage-sensitive effect |
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Legal Events
| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
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| AV01 | Patent right actively abandoned | ||
| AV01 | Patent right actively abandoned | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20160810 Effective date of abandoning: 20190405 |
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| AV01 | Patent right actively abandoned |
Granted publication date: 20160810 Effective date of abandoning: 20190405 |