Minor diameter rock mass hydrofracturing tests straddle packer
The present invention relates to a kind of minor diameter rock mass testing tools, specifically, being related to a kind of minor diameter rock mass hydrofracturing
Test straddle packer.
Hubbert and Willis proposes that crack caused by well bore fluid pressure break is answered with institute preservation in rock mass in nineteen fifty-seven
Power state is closely related, and points out that rock mass pressure is not at hydrostatic pressure state.Kehle(1964) packer is isolated for the first time
The stress distribution on wellhole periphery of experimental section carried out simple analysis, and point out that the influence of packer forms hole wall periphery and cuts
Stressed zone.Fairhurst(1964 it is) first scientist for proposing to measure Original strata stress using hydrofracturing technology, and refers to
The plurality of advantages of hydrofracturing technology is gone out.Haimson and Fairhurst(1967) point out the crack generated on the borehole wall with it is following
Three factors are related, 1. crustal stress, 2. the poor stress between the fluid pressure and pore water pressure of hydrofracturing；3. rock mass seeps
Saturating radial flow, these theory analysis have established the theoretical basis of classical hydrofracturing measuring technology.Haimson(1968) exist
In its doctoral thesis to hydrofracturing Original strata stress measuring technology from experiment and theoretical two aspects carried out comprehensive analysis with it is complete
It is kind.The above important process is that hydrofracturing Original strata stress measuring technology has established theory applied to engineering practice and tested base
Plinth.The stress measurement engineering practice of real meaning is by Von Schonfeldt and Fairhurst(1970) study group of leader
It is unfolded in a Minnesotan underground granitic mass；Then, similar stress has also been carried out in the oil field Rangely
Measurement and research work (Haimson, 1973；Raleigh etc., 1976).From this, Hydraulic Fracturing Stress Measurements formally enter engineering
Practice field.1987 and 2003, International Society of Rock Mechanics was all using hydrofracturing In-situ stress measurements method as one kind
Main stress evaluation method is recommended, and has also established weight of the hydrofracturing In-situ stress measurements technology as stress test method
The geostress survey work of China is slightly later than foreign countries, and the fifties end, LI Si guang and professor Chen Zongji instruct respectively
Geomechanics and Three Gorges batholith workshop start.In October, 1980, the study group led by professor Li Fangquan is in river
Northern Yi County has successfully carried out hydraulic fracturing geostress survey (Li Fangquan, 1980) for the first time, and subsequent China Seismology Bureau's earth's crust is answered
Power Research Institute success lightweight hydrofracturing measuring device (Li Fangquan, 1981；Ding Jianmin, 1990；An Qimei, 1996；Guo
Qi Liang, 1999).Hydrofracturing measuring technology starts to be widely used popularization in all trades and professions of China.Up to the present,
The main hydrofracturing test method that China uses abides by the method that International Society of Rock Mechanics is recommended.
Equipment about hydrofracturing In-situ stress measurements is broadly divided into five major class at present: (1) heavy duty cables formula hydraulic pressure causes
In-situ stress measurements equipment is split, using Switzerland's MESY-SOLEXPERTS equipment as representative；(2) light cable type hydrofracturing original place
Stress measurement equipment, mainly using the shallow bore hole test equipment of CSIR O of Japanese OYO company and Australia tissue manufacture as representative；
(3 are tested hydrofracturing and other physical prospecting mud logging equipments with what French Cornet professor and U.S. professor Thiercelin made
The novel hydrofracturing test equipment combined is representative；(4) it is surveyed with the BABHY of northeastern Japan university professor Ito manufacture
Examination equipment is representative；(5) the widely used drilling rod formula hydrofracturing In-situ stress measurements equipment in Chinese range.All this
In a little equipment, the smallest device diameters are the lightweight hydrofracturing In-situ stress measurements equipment of CSIR O tissue manufacture, and equipment is straight
Diameter is Ф 36mm, is secondly the BABHY test equipment of professor's Ito manufacture, testing bore holes diameter is Ф 48mm.
Widely used measuring system is made of six parts at home, pressure fluid control system, high-pressure hydraulic pump, power
System, digital data recording system, straddle packer and high-pressure fluid transportation system.This measuring system is divided into two classes again, a kind of
It is the shallow bore hole for 100m, drilling rod and high pressure resistant hose can be used and realize pressure break to packer and fracturing section water supply respectively.Separately
A kind of outer equipment is the longhole survey for 100m or more, and pressure fluid is supplied respectively to fracturing section and envelope using a switching valve
Every device, measurement system diagram is as illustrated in fig. 1 and 2.Wherein: 40,30: drilling cramp, 41: high-pressure hose, 42,32: drilling rod is connected to test section,
43,33: adapter, 44,34: test section, 45,35: packer, 46,36: pressure sensor.
By the analysis of front it is found that there are no the hydrofracturing detecting earth stress systems that diameter is less than 36mm in the world at present
System.But the hydrofracturing Original strata stress test macro of minor diameter has equipment light, requires low spy to test pressurized equipment
The high-pressure oil pump pressurization of the annual compression system or two-phase electricity of high output pressure and low discharge can be used in point.At the same time,
Requirement of the minor diameter test equipment to rockmass is low, for bigbore drilling, surveys according to International Society of Rock Mechanics
Examination segment length should be 6 ~ 7 times of bore diameter, then adding for domestic conventional 76mm 94mm geological prospecting borehole
Upper packer length 1.0m or so, then 245.6cm ~ 256.4cm is at least to the length of drilling rockmass, but for one
For a diameter is the drilling of 32mm, it is only necessary to the rockmass length of about 99.2cm long, it is only original less than 40%,
Under identical working condition, so that it may so that amount of test data has more more than one times.At the same time, the brill that drills makes expense can be with brill
Hole aperture becomes smaller and reduces, this is greatly lowered the testing expense of Original strata stress, and the testing time of slim hole also can
Shorten therewith, so that testing expense substantially reduces.Therefore, the research and development of minor diameter Original strata stress test equipment, for pushing
Hydrofracturing In-situ stress measurements and promotion original technology upgrading innovation have important social effect and economic significance.
For minor diameter hydrofracturing test macro, the drilling rod used in conventional hydrofracturing Original strata stress is tested,
The fixture diameters such as high-pressure rubber pipe are excessive, can not be installed into highly pressurised liquid and test equipment using original technological approaches predetermined
Position.The present invention uses existing technology path, using double back line structure, by two circuits in packer give respectively fracturing section and
Packer sealing section provides highly pressurised liquid, designs and manufacture the straddle packer of minor diameter hydrofracturing test device.
Summary of the invention
The present invention is precisely in order to a kind of minor diameter rock mass hydrofracturing test bridging for solving above-mentioned technical problem and designing
The technical solution adopted by the present invention to solve the technical problems is:
A kind of minor diameter rock mass hydrofracturing test straddle packer, including double loop mounting rod connector, a upper packing
Device, a connector with hole for water spraying, a lower packet and a lower end cap；Double loop mounting rod connector, upper packer,
Connector, lower packet and lower end cap with hole for water spraying are successively closely coupled.
The minor diameter rock mass hydrofracturing tests straddle packer, and the material of double loop mounting rod connector is 304
There is screw thread at stainless steel, both ends, are separately connected double loop mounting rod and upper packer, the packer of double loop mounting rod connector
Inlet opening is connected to packer rubber tube channel, and the fracturing section inlet opening connection packer fracturing section of double loop mounting rod connector is logical
Road；Respectively there is a circle groove at double loop mounting rod connector both ends, at the mounting rod connector connecting groove of double loop and with packing
O-shaped rubber seal is worn at device connecting groove respectively, realizes and is threadedly coupled end face sealing.
The minor diameter rock mass hydrofracturing tests straddle packer, the packer water inlet of double loop mounting rod connector
Hole and fracturing section inlet opening, diameter are Φ 6mm.
The minor diameter rock mass hydrofracturing tests straddle packer, and upper packer and lower packet are same model,
Its internal structure is identical, is Inflatable type packer rubber sleeve, and Inflatable type packer rubber sleeve has two kinds of models of Φ 31mm and Φ 39mm；
Two kinds of packer pressure resistances reach 40MPa, and heatproof reaches 130 DEG C.
The minor diameter rock mass hydrofracturing tests straddle packer, and upper and lower packer includes upper linkage section, expansion
Seal section and lower linkage section；Upper and lower packer both ends have connection screw thread, and having inside intermediate expansion seal section enhances its intensity
The minor diameter rock mass hydrofracturing tests straddle packer, and the connector material with hole for water spraying is 304 stainless
There is screw thread at steel, connector both ends, and upper and lower two packers are connected；There are two channels in connector, are packer respectively
Channel and fracturing section channel；Wherein pass through a Φ 6mm among fracturing section channel, the stainless steel tube of wall thickness 1.5mm, the steel pipe with
Lower end cap bottom firmly welds together；There are three the hole for water spraying for being connected to fracturing section channel, packer channels on the connectors
The rubber tube of upper packer and lower packet is connected, connector wears O-shaped rubber seal at upper and lower packer connecting groove,
It realizes and is threadedly coupled end face sealing.
The minor diameter rock mass hydrofracturing tests straddle packer, and lower end cap material is 304 stainless steels, and front end has
Screw thread is connect with lower packet, and rear end increases its frictional force in surface rolling cruciate flower, welds a Φ 6mm, wall in the middle part of lower end cap
304 stainless steel tubes of thick 1.5mm, the stainless steel tube be pressure break channel, stainless steel tube length be 1.18m, the bottom of lower end cap with
Stainless steel tube firmly welds together, high pressure resistant and air tight；And O-shaped rubber seal is worn in groove, realizes that screw thread connects
Contact surface sealing.
Present invention is mainly used for the slim hole hydrofracturing of rock mass test in, function be in drill one section completely
The palisades of rock mass seal, sealing space is formed, to provide the function of high-pressure-resistant sealed in subsequent development hydrofracturing operation
Energy.By inventing the straddle packer, a diameter of 30 ± 1mm of Ф, 39 ± 1mm of Φ, and pressure resistance reaches 40MPa, Ke Yishi
The live hydrofracturing test of existing rock mass medium-small diameter drilling.
Minor diameter straddle packer carries out minor diameter hydrofracturing Original strata stress test job through the invention, meets
The requirement of two kinds of 30 ± 1mm of packer outer dimension Φ, 39 ± 1mm of Φ and pressure resistance 40MPa, while seal approach also meets pressure resistance
The requirement of 40MPa.Packer and fracturing section is given to supply water respectively using two inlet openings of double loop mounting rod connector, by upper
The hole for water spraying of connector is sealed the hydrofracturing test of section between lower two packers, and at the same time monitoring fracturing section and envelope
Every the pressure value of device, be conducive to the stress database for obtaining high quality, realization is surveyed in Φ 38mm and Φ 44mm minor diameter geology
Hydrofracturing In-situ stress measurements in prospecting bit hole.
The beneficial effects of the present invention are: the hydrofracturing In-situ stress measurements scheme in slim hole is realized, this
Straddle packer has two kinds of specifications of Φ 30mm and Φ 39mm, and structure is simple, and it is convenient to assemble, and is connected by double loop mounting rod
This five components of head, upper packer, the connector with hole for water spraying, lower packet and lower end cap realize hydraulic pressure in slim hole
The test section of fracturing In-situ stress measurements seals and the injection of highly pressurised liquid.
Detailed description of the invention
Fig. 1 is existing double back path test system hydrofracturing In-situ stress measurements device straddle packer schematic diagram.
Fig. 2 is existing single loop test macro hydrofracturing In-situ stress measurements device straddle packer schematic diagram.
Fig. 3 is straddle packer whole interior structural schematic diagram of the present invention.
Fig. 4 is mounting rod connector mechanical construction drawing in double loop of the present invention.
Fig. 5 is packer mechanical construction drawing of the present invention.
Fig. 6 is the connector mechanical construction drawing of the invention with hole for water spraying.
Fig. 7 is lower end cap mechanical construction drawing of the present invention.
Present invention will be further explained below with reference to the attached drawings and examples.
As shown in fig. 3 to 7, a kind of minor diameter rock mass hydrofracturing of the present invention tests straddle packer, including double loop peace
Fill the 4, lower packets 7 of connector of the upper packer 2, one of bar connector 1, one with hole for water spraying 3 and one 8 groups of lower end cap
At；Double loop mounting rod connector 1, upper packer 2, the connector 4 with hole for water spraying 3, lower packet 7 and lower end cap 8 are successively tight
It is close to be connected.
The minor diameter rock mass hydrofracturing tests straddle packer, and the material of double loop mounting rod connector 1 is 304
There is screw thread at stainless steel, both ends, are separately connected double loop mounting rod and upper packer, the packing of double loop mounting rod connector 1
Device inlet opening 5 is connected to packer rubber tube channel 12, and the fracturing section inlet opening 6 of double loop mounting rod connector 1 is connected to packer
Fracturing section channel 13；Respectively there is a circle groove 11 at mounting rod connector 1 both ends in double loop, and in double loop, the connection of mounting rod connector is recessed
At slot 11 and with wear O-shaped rubber seal at packer connecting groove 11 respectively, realize and be threadedly coupled end face sealing.
The minor diameter rock mass hydrofracturing tests straddle packer, the packer of double loop mounting rod connector 1 into
Water hole 5 and fracturing section inlet opening 6, diameter are Φ 6mm.
The minor diameter rock mass hydrofracturing tests straddle packer, and upper packer 2 and lower packet 7 are same type
Number, it is Inflatable type packer rubber sleeve that internal structure is identical, and Inflatable type packer rubber sleeve has two kinds of types of Φ 31mm and Φ 39mm
Number；Two kinds of packer pressure resistances reach 40MPa, and heatproof reaches 130 DEG C.
In the measurement process of hydrofracturing Original strata stress, as shown in figure 4, highly pressurised liquid is respectively out of double loop mounting rod
Two channels in portion enter fracturing section inlet opening and packer inlet opening, and wherein highly pressurised liquid passes through fracturing section inlet opening and connection
The internal pipeline of head enters the fracturing section channel between packer, and another way highly pressurised liquid passes through packer inlet opening and connector
Internal pipeline enter the channel inside packer rubber tube, expand the rubber tube in the middle part of packer, reach to hole wall seal
Effect.And it is close at the mounting rod connector connecting groove of double loop and with O-shaped rubber is worn respectively at packer connecting groove
Seal has the function that be threadedly coupled end face sealing.
The minor diameter rock mass hydrofracturing tests straddle packer, and upper and lower packer 2,7 includes upper linkage section
14, Expansion sealing section 15 and lower linkage section 16；Upper and lower packer 2,7 both ends have connection screw thread 17, intermediate expansion seal section
There is the steel disc 18 for enhancing its intensity inside 15.As shown in figure 5, highly pressurised liquid is logical during hydrofracturing In-situ stress measurements
It crosses internal pipeline and enters Expansion sealing section and expanded, and be allowed to be bonded with hole wall, test is reached by upper and lower two packers
The requirement of section sealing.
The minor diameter rock mass hydrofracturing tests straddle packer, and 4 material of connector with hole for water spraying 3 is not 304 not
Become rusty steel, and there is screw thread at connector both ends, upper and lower two packers is connected, as shown in Figure 6；There are two logical in connector 4
Road is packer channel 21 and fracturing section channel 22 respectively；Wherein intermediate fracturing section channel 22 passes through a Φ 6mm, wall thickness
The stainless steel tube of 1.5mm, the steel pipe firmly weld together with 8 bottom of lower end cap；There are three be connected to pressure break on connector 4
The hole for water spraying 3 of Duan Tongdao 22, the outside injection for highly pressurised liquid during hydrofracturing.It is sealed in the connection of packer channel 21
Drilling hole is realized for expansion of the highly pressurised liquid to rubber tube during hydrofracturing every the rubber tube of device and lower packet
The sealing of wall fracturing section.Connector 4 wears O-shaped rubber seal at upper and lower packer connecting groove 20, realizes threaded ends
The minor diameter rock mass hydrofracturing tests straddle packer, and 8 material of lower end cap is 304 stainless steels, front end
There is screw thread to connect with lower packet, rear end increases its frictional force in surface rolling cruciate flower, a Φ 6mm is welded in the middle part of lower end cap 8,
304 stainless steel tubes of wall thickness 1.5mm, the stainless steel tube are pressure break channel 24, and stainless steel tube length is 1.18m, the bottom of lower end cap
Portion firmly welds together with stainless steel tube, high pressure resistant and air tight；And O-shaped rubber seal is worn in groove 23, is realized
It is threadedly coupled end face sealing.
The in vitro Original strata stress test simulation environment of this set equipment is tested, and application effect is good, experiment
Process is described in detail as follows:
(1) be Ф 34mm using internal diameter, the steel pipe of Ф 44mm simulates live slim hole, by high-pressure oil pump, high-pressure fluid control
System processed, double loop mounting rod, minor diameter straddle packer connect.
(2) oil pump outlet valve is opened, fracturing section ball valve and pressure relief ball valve are closed, pressurizes to packer, examines setting function,
Packer monitors pressure gauge and shows packer pressure resistance 40MPa, and setting ability is good.
(3) oil pump outlet valve is opened, packer needle-valve and pressure relief ball valve are closed, is pressurizeed to fracturing section, pressure break function is examined,
Fracturing section monitors pressure gauge and shows fracturing section pressure resistance 40MPa, packer pressure 50MPa, and high-pressure fluid pressure break fan-out capability is good.
(4) in test process, each connector leakproofness is good, does not have evaporating, emitting, dripping or leaking of liquid or gas phenomenon, and pressure maintains stability good
It is good.
(5) oil pump oil return valve is opened, delivery valve is closed, opens packer needle-valve, fracturing section ball valve, pressure relief ball valve, is completed
The present invention is not limited to above-mentioned preferred forms, anyone obtain under the inspiration of the present invention other it is any with
The identical or similar product of the present invention, is within the scope of the present invention.