CN102353550B - Combination property experimental device and performance estimating method for sand-preventing sieve tube - Google Patents

Abstract

The invention discloses a combination property experimental device and a performance estimating method for a sand-preventing sieve tube, which belong to the technical field of loose sandstone oil and gas field development. The device comprises a closed main tank body, a simulating well wall sleeve, a simulating casing, a simulating jet hole eyelet and a fastening tie rod; the main tank body comprises a top cover, a barrel side wall and a supporting bottom; the side wall of the main tank body is provided with eight liquid inlets; the supporting bottom is provided with one liquid outlet and seven pressure testing holes; the top cover is provided with two air exit holes and four assembling hanging rings; both the simulating well wall sleeve and the simulating casing are steel barrels with a plurality of eyelets, are nested in the main tank body and are detachable; the simulating eyelet is a plastic short pipe with better flexility; and the fastening tie rod is a specially-made steel bolt. By using the combination property experimental device and the performance estimating method for the sand-preventing sieve tube, sand-preventing well completion conditions, such as the sand prevention and the gravel packing sand prevention and the like of a jet hole, a bare hole and a sieve tube can be simulated; the radial flow state at the bottom of an actual well is simulated; collected data of flow rate, pressure and sand production rate are analyzed; and one set of performance evaluating method for the sand-preventing sieve tube is provided.

Description

A kind of sand control screen comprehensive performance detection experimental device and method of evaluating performance

Technical field

The present invention relates to a kind of sand control screen comprehensive performance detection experimental device and method of evaluating performance, belong to understressed sand oil-gas field development technical field.

Background technology

At present, shake out and become one of subject matter facing in understressed sand hydrocarbon-bearing pool recovery process, sand control is the main path that solves the problem of shaking out.Sand control screen is widely applied in sand proof well as main down-hole sand-proof tool.The sand control screen adopting is at present of a great variety, comprises wire wrapped screen, slotted screen, double-deck pre-pack gravel wire wrapped screen, metal wool sand screen, ceramic sand filtering pipe etc.The sand block medium of these screen casings is different, and its sand controlling result depends on the factors such as screen casing self character and reservoir sand and fluid properties.

Sand control screen is widely applied in Oil/gas Well sand control completion and operation, and its type selecting is most important for obtaining good sand controlling result with design.By experiment screen casing properties being carried out to scientific evaluation is the effective means of carrying out screen casing type selecting and design.In actual production, if screen casing can not effectively stop reservoir sand or the blocked serious reduction production capacity of screen casing, mean that sand control lost efficacy or failure.Therefore, the screen casing that sand controlling result is good must meet two conditions: the one, be not easy blocked, the production time of growing as far as possible in blocked front maintenance; The 2nd, can effectively stop that reservoir sand passes through, more few better by the reservoir sand of screen casing.The former is called the anti-blockage capability of screen casing, and the latter is called the sand block ability of screen casing.Still lack and can reflect the evaluation method of the above-mentioned properties of sand control screen and combination property and supporting experiment detection means at present.

Summary of the invention

For the deficiencies in the prior art, the invention provides a kind of sand control screen comprehensive performance detection experimental device and method of evaluating performance.

A kind of sand control screen comprehensive performance detection experimental device, comprises airtight main tank body, simulation borehole wall sleeve, analog casing, analogue perforation eyelet and fastening pull rod; Dismountable simulation borehole wall sleeve and analog casing are all nested in airtight main tank body, are positioned at the axle center place of airtight main tank body; Analogue perforation eyelet is assemblied in the eyelet of simulation borehole wall sleeve and analog casing; Be connected for the fastening pull rod of fastening main tank body and the top cover of main tank body and support base; Described sand control screen comprehensive performance detection experimental device is also provided with shunt volume system, constant current liquid-supplying system, flow real-time monitoring system, sand production rate monitoring system and pressure real-time acquisition system.

Described airtight main tank body is cylindric, and it is made up of top cover, sidewall and support base; Top cover top is provided with 2 vent ports and 4 assembling suspension ring; Sidewall outside is provided with 8 inlets, and inlet is divided into two-layer up and down, and every one deck is made as 4, is uniformly distributed in the surrounding of sidewall; Support base top has 4 fitting recess, and lower central place is provided with a liquid outlet, and support base is also provided with 7 pressure taps; Airtight main tank body and connected all parts are all tightly connected.

Described simulation borehole wall sleeve and analog casing are the steel cylinder with multiple eyelets.

Described analogue perforation eyelet is the plastic tubulature that pliability is good.

Described fastening pull rod is Steel Bolt.

Described shunt volume system is the part flow arrangement with 1 inlet and 8 liquid outlets, is connected respectively with the liquid outlet of constant current liquid-supplying system and the inlet of main tank body; Described constant current liquid-supplying system comprises fluid reservoir and constant flow pump, is connected with the inlet of main tank body by shunt volume system; Described flow real-time acquisition system comprises flowmeter and data acquisition computer, and flowmeter is connected with collection computer, and flow real-time acquisition system is connected with the liquid outlet of main tank body; Described sand production rate monitoring system is the sand collector with transparent collection sand graduated cylinder, is connected with the liquid outlet of main tank body; Described pressure real-time acquisition system comprises 7 pressure transducers, is separately positioned between 1, main tank body liquid outlet place, main tank body cylinder side wall and simulation borehole wall sleeve 3 between 3, simulation borehole wall sleeve and analog casing.

Described sand production rate monitoring system is cylindric sand collector, comprises cylinder shell, sand collector liquid outlet, filter sand net back-up ring, filter sand net, taper shell, sand collector support, sand collector spigot, valve, spigot pipe nipple, collection sand graduated cylinder and sand collector inlet; Described filter sand net is circular filter screen; Described taper shell is coniform, and lower end and spigot join; Valve is conventional pipeline valve; Described collection sand graduated cylinder is for being with graduated transparent organic glass cylinder; Described sand collector inlet is the outwardly directed one section of pipe of taper shell, is connected with the liquid outlet of main tank body.

The various combined situation such as described experimental provision can analogue perforation, bore hole, screen sand control, gravel filling sand prevention, its assembling and filling situation are as follows:

A. perforation completion screen sand control: four-layer structure is complete is filled reservoir sand in simulation borehole wall sleeve and main tank wall annular space, evaluates perforation completion screen casing performance;

B. perforation completion gravel filling sand prevention: four-layer structure is complete is filled reservoir sand in simulation borehole wall sleeve and main tank wall annular space; Between analog casing and screen casing sample, annular space is filled gravel bed, evaluates gravel bed performance;

C. open hole completion screen sand control: four-layer structure is complete, removes analogue perforation eyelet, in simulation borehole wall sleeve and analog casing annular space, fills reservoir sand, evaluates open hole completion screen casing performance;

D. open hole completion gravel filling sand prevention: four-layer structure is complete, removes analogue perforation eyelet, in simulation borehole wall sleeve and analog casing annular space, fills reservoir sand, between screen casing and analog casing, fills gravel, evaluates open hole completion gravel bed performance.

The experimental technique of sand control screen Performance Detection experimental provision is as follows:

1) close the valve of main tank body liquid outlet, preparing experiment displacing fluid, clear water or oil or both mixed liquors for displacing fluid;

2) put into sand control completion mode filling reservoir sand and the gravel that screen casing to be evaluated basis will be simulated;

3) turn on pump, is full of displacing fluid in advance by main tank body, covers top cover fastening;

4) open the valve of main tank body liquid outlet, be adjusted to and specify pumping rate to start experiment, and open experimental data real-time acquisition system, every a sand production rate of 5-10 minute record;

5) displacement is stable gradually to screen casing pressure at both sides, closes pump and stops real time data acquisition, records final sand production rate;

6) cleaning experimental provision, takes out reservoir sand and gravel cleaning experiment device;

7) carry out data processing and interpretation of result.

A kind of sand control screen Performance Evaluating Indexes, comprising: the trafficability performance evaluation index of the ability that a. passes through for quantitative evaluation screen casing permission resident fluid; B. for the sand block Performance Evaluating Indexes of the reservoir sand ability that stops of quantitative evaluation sand control screen; C. resist the performance of anti-blockage evaluation index of shale, fine sand tamper blocking ability for quantitative evaluation sand control screen; D. for the comprehensive performance evaluation index of the combination property of the different screen casings of quantitative evaluation.

Described sand control screen method of evaluating performance is the evaluation index of calculating respectively sand block performance, trafficability performance and the performance of anti-blockage of sand control screen according to experimental result data, then set rational weight coefficient for each evaluation index, calculate the quality of comprehensive function index reflection screen casing three aspects: overall performance, calculate the balanced intensity of balanced index reflection properties, and then calculate integrated performance index, complete the performance evaluation contrast under the same conditions of different screen casings, its concrete evaluation method is as follows:

(1) screen casing trafficability performance evaluation method

The present invention uses screen casing trafficability performance evaluation index S _lcharacterize the trafficability performance of screen casing.With the composite permeability k of sand control screen _scharacterize its trafficability performance, screen casing both sides pressure reduction and the data on flows in the each moment obtaining according to experiment, calculate corresponding permeability and be:

$k_{\mathrm{si}}=\frac{q_i\mathrm{\μ}}{{2\mathrm{\πL}}_s{\mathrm{\ΔP}}_i}\·\ln \frac{d_{\mathrm{so}}}{d_{\mathrm{si}}},$ Formula 1;

Wherein, μ is the viscosity of experiment fluid, L _sfor the effective length of experiment screen casing, d _sofor experiment screen casing external diameter, d _sifor testing sieve bore, q _ibe the i moment by the flow of screen casing, Δ P _ibe the inside and outside both sides of i moment screen casing pressure reduction, k _siit is the permeability of i moment screen casing;

Described screen casing composite permeability k _sfor the initial permeability k of screen casing _s0with the mean permeability k in experimentation _saaccording to coefficient X _kweighted mean value, its computing formula is:

K _s=k _s0x _k+ k _sa(1-X _k), formula 2;

$k_{\mathrm{sa}}=\frac{1}{N}\·\underset{i}{\overset{N}{\mathrm{\Σ}}}{k}_{\mathrm{si}},$ Formula 3;

Wherein, the number of test points that N is experimentation, k _s0for the initial permeability of experiment screen casing, k _safor the mean permeability of screen casing in experimentation, X _kfor weighted mean coefficient, get X _k=0.5;

For the ease of the trafficability performance contrast of multiple screen casing, the present invention proposes many screen casings trafficability performance index computing formula and is:

$S_{l\left(j\right)}=\frac{k_{s\left(j\right)}}{k_{s\max }},$ Formula 4;

Wherein, k _{s (j)}be the composite permeability of j screen casing, k _smaxfor the composite permeability maximal value of whole screen casings, S _{l (j)}it is the trafficability performance evaluation index of j screen casing;

(2) screen casing sand block method of evaluating performance

The present invention uses screen casing sand block Performance Evaluating Indexes S _dcharacterize the sand block performance of screen casing.Described screen casing sand block Performance Evaluating Indexes S _dcomputing formula is:

$S_d=\frac{V_t\·R-V_s}{V_t\·R},$ Formula 5;

Wherein, V _sfor passing through the reservoir sand cumulative volume of screen casing, V in experiment _tby in experiment the cumulative volume of use reservoir sand, R was for allowing sand ratio;

(V in this evaluation index computing formula _tr) for allowing sand production rate, (V _tr-V _s) may be by screen casing in the reservoir sand that uses for experiment but there is no the reservoir sand volume of output, the index calculating is between 0-1, and the larger expression screen casing of this desired value sand block performance is better;

Allowed sand than referring to the scale-up factor that is less than testing sieve management in the reservoir sand that experiment is used and thinks the shared cumulative volume of reservoir sand volume of filtering accuracy, it can analyse curve according to stratum sand sieve, reservoir sand volume is tried to achieve with screen casing ideal filtering accuracy;

(3) screen casing performance of anti-blockage evaluation method

The present invention uses screen casing performance of anti-blockage evaluation index S _kcharacterize the performance of anti-blockage of screen casing.The displacement pressure reduction of sand control screen refers to the pressure differential that screen casing is outside and inner, can reflect the quality of screen casing performance of anti-blockage; Described screen casing performance of anti-blockage evaluation index S _kfor displacement pressure reduction mean value and the ratio of initial displacement pressure reduction, its computing formula is:

$S_k=\frac{P_0}{\stackrel{\‾}{P}},$ Formula 6;

Wherein, P ₀for initial displacement pressure reduction, the mean value of front certain a period of time or some data points in desirable experimentation,

for the average displacement pressure reduction in whole evaluation time;

S _k>=1 represents that screen casing does not exist blockage problem, S _k< 1 represents that screen casing exists blockage problem; S _klarger, represent that performance of anti-blockage is better, S _kless, represent that performance of anti-blockage is poorer;

(4) screen casing comprehensive performance evaluation method

The present invention uses screen casing comprehensive performance evaluation index S to characterize the combination property of screen casing.In order to characterize the quality of screen casing overall performance, the present invention proposes screen casing functional parameter S ₁, being defined as the weighted mean value of trafficability performance index, sand block performance index and performance of anti-blockage index, its computing formula is:

S ₁=W _ks _k+ W _ls _l+ W _ds _d, formula 7;

W _k+ W _l+ W _d=1, formula 8;

Wherein, W _kfor screen casing performance of anti-blockage evaluation weight coefficient, recommend W _k=0.4; W _lfor screen casing trafficability performance evaluation weight coefficient, recommend W _l=0.3; W _dfor screen casing sand block performance evaluation weight coefficient, recommend W _d=0.3;

Well behaved screen casing not only requires the weighted mean value of trafficability performance, sand block performance, performance of anti-blockage to want high, but also requires above-mentioned three performance relative equilibriums of screen casing, and the present invention proposes the balanced index S of screen casing thus ₂for:

S ₂=| S _k-S _l|+| S _k-S _d|+| S _l-S _d|, formula 9;

The functional parameter S of screen casing ₁larger, balanced index S ₂less, the combination property of screen casing is better, therefore proposes described screen casing comprehensive performance evaluation index to be:

S=S ₁-S ₂, formula 10;

Wherein, the comprehensive performance evaluation index S of screen casing is larger, and the combination property of screen casing is better.

The present invention compared with prior art tool has the following advantages:

1. the present invention directly adopts the gravel of the conventional sand control screen in oil field and filling to test indoor, draws materials conveniently, and simple to operate, sensing range is wide.

2. the real Radial Flow state of simulation oil well well fluids downhole of the present invention, test result is more genuine and believable, and evaluation result is preferably etc. all to have very important significance for the design and construction of oil field actual production, sand control and sand control screen.

The present invention can analogue perforation completion, four kinds of perforations such as screen sand control, gravel filling sand prevention under open hole completion mode and the combined situation of sand control method, can evaluate at present nearly all conventional screen casing and the sand control capability of gravel packing zone, range of application is very extensive.

4. the present invention proposes a set of sand control screen Performance Evaluating Indexes, covered trafficability performance, sand block performance, performance of anti-blockage and the combination property of screen casing, this index system provides quantitative target for sand control screen performance evaluation.

5. the present invention has set up a set of sand control screen method of evaluating performance based on experimental data, by the calculating to properties evaluation index, realize the quantitative evaluation to the sand block such as sand control screen and gravel bed medium sand control capability, Oil Field application and screen casing production have all been had to extraordinary realistic meaning.

The present invention can be according to different completion mode reasonable regulation experiment scheme, Radial Flow state under simulation downhole condition, the more approaching production of evaluation result is actual, the pressure of experiment real-time monitoring system energy Real-Time Monitoring sand control screen, the Changing Pattern of flow and sand production rate, after experiment, can make the performance index comparison diagram of different sand control screens, can be to single screen casing, the sand block performance of multiple screen casing and gravel packing zone, trafficability performance, performance of anti-blockage and combination property are evaluated contrast, optimize the sand control screen of best performance, preferably significant to field sand control parameter designing and sand control project.

Brief description of the drawings

Fig. 1 is sand control screen comprehensive performance detection experimental device vertical view.

Fig. 2 is sand control screen comprehensive performance detection experimental device front view, i.e. Figure 1A-A-A direction cross section structure schematic diagram.

Fig. 3 is that sand control screen comprehensive performance detection experimental device removes the vertical view after top cover.

Fig. 4 is that sand control screen comprehensive performance detection experimental device connects and schematic flow sheet.

Fig. 5 is that the sand collector of sand production rate detection system removes the vertical view after filter sand net.

Fig. 6 is the sand collector structural representation of sand production rate detection system, i.e. Fig. 5 B-B direction schematic cross-section.

Fig. 7 can pass through the wide reservoir sand percent by volume of screen casing maximum seam schematic diagram according to the wide judgement of screen casing maximum seam.

Fig. 8 is displacement pressure reduction temporal evolution curve synoptic diagram.

Fig. 9 is the program flow diagram of the evaluation method of evaluation index of the present invention.

In figure 1, top cover, 2, sidewall, 3, support base, 4, simulation borehole wall sleeve, 5, analog casing, 6, simulation eyelet plug, 7, analogue perforation eyelet, 8, screen casing, 9, pressure tap, 10, vent port, 11, assembling suspension ring, 12, fastening pull rod, 13, inlet, 14, liquid outlet, 15, fitting recess, 16, pilot hole, 17, shunt volume system, 18, constant current liquid-supplying system, 19, flow real-time acquisition system, 20, sand production rate monitoring system, 21, pressure real-time acquisition system, 22, cylinder shell, 23, sand collector liquid outlet, 24, filter sand net back-up ring, 25, filter sand net, 26, taper shell, 27, sand collector support, 28, sand collector spigot, 29, valve, 30, spigot pipe nipple, 31, . collection sand graduated cylinder, 32, sand collector inlet.

Embodiment

Below in conjunction with drawings and Examples, the present invention will be further described.

Embodiment:

A kind of sand control screen comprehensive performance detection experimental device, as shown in Fig. 1-Fig. 6, comprises airtight main tank body, simulation borehole wall sleeve 4, analog casing 5, analogue perforation eyelet 7 and fastening pull rod 12; Dismountable simulation borehole wall sleeve 4 and analog casing 5 are all nested in airtight main tank body, are positioned at the axle center place of airtight main tank body; Analogue perforation eyelet 7 is assemblied in the eyelet of simulation borehole wall sleeve 4 and analog casing 5; Be connected for the fastening pull rod 12 of fastening main tank body and the top cover 1 of main tank body and support base 3; Described sand control screen comprehensive performance detection experimental device is also provided with shunt volume system 17, constant current liquid-supplying system 18, flow real-time monitoring system 19, sand production rate monitoring system 20 and pressure real-time acquisition system 21.

Described airtight main tank body is cylindric, and it is made up of top cover 1, sidewall 2 and support base 3; Top cover 1 top is provided with 10 and 4 assembling suspension ring 11 of 2 vent ports; Sidewall 2 outsides are provided with 8 inlets 13, and inlet is divided into two-layer up and down, and every one deck is made as 4, are uniformly distributed in the surrounding of sidewall 2; Support base 3 tops have 4 fitting recess 15, and lower central place is provided with a liquid outlet 14, and support base 3 is also provided with 7 pressure taps; Airtight main tank body and connected all parts are all tightly connected.

Described simulation borehole wall sleeve 4 and analog casing 5 are the steel cylinder with multiple eyelets.

Described analogue perforation eyelet 7 is the plastic tubulature that pliability is good.

Described fastening pull rod 12 is Steel Bolt.

Described shunt volume system 17, for having the part flow arrangement of 1 inlet and 8 liquid outlets, is connected with the liquid outlet of constant current liquid-supplying system 18 and the inlet of main tank body 13 respectively; Described constant current liquid-supplying system 18 comprises fluid reservoir and constant flow pump, is connected with the inlet 13 of main tank body by shunt volume system 17; Described flow real-time acquisition system 19 comprises flowmeter and data acquisition computer, and flowmeter is connected with collection computer, and flow real-time acquisition system 19 is connected with the liquid outlet 14 of main tank body; Described sand production rate monitoring system 20 is the sand collector with transparent collection sand graduated cylinder, is connected with the liquid outlet 14 of main tank body; Described pressure real-time acquisition system comprises 7 pressure transducers, is separately positioned between 1, main tank body liquid outlet 14 place, main tank body cylinder side wall 2 and simulation borehole wall sleeve 43 between 3, simulation borehole wall sleeve 4 and analog casing 5.

Described sand production rate monitoring system 20 is cylindric sand collector, comprises cylinder shell 22, sand collector liquid outlet 23, filter sand net back-up ring 24, filter sand net 25, taper shell 26, sand collector support 27, sand collector spigot 28, valve 29, spigot pipe nipple 30, collection sand graduated cylinder 31 and sand collector inlet 32; Described filter sand net 25 is circular filter screen; Described taper shell 26 is coniform, and lower end and spigot join; Valve 29 is conventional pipeline valve; Described collection sand graduated cylinder 31 is for being with graduated transparent organic glass cylinder; Described sand collector inlet 32 is the outwardly directed one section of pipe of taper shell, is connected with the liquid outlet 14 of main tank body.

The various combined situation such as described experimental provision can analogue perforation, bore hole, screen sand control, gravel filling sand prevention, its assembling and filling situation are as follows:

A. perforation completion screen sand control: four-layer structure is complete is filled reservoir sand in simulation borehole wall sleeve and main tank wall annular space, evaluates perforation completion screen casing performance;

B. perforation completion gravel filling sand prevention: four-layer structure is complete is filled reservoir sand in simulation borehole wall sleeve and main tank wall annular space; Between analog casing and screen casing sample, annular space is filled gravel bed, evaluates gravel bed performance;

C. open hole completion screen sand control: four-layer structure is complete, removes analogue perforation eyelet, in simulation borehole wall sleeve and analog casing annular space, fills reservoir sand, evaluates open hole completion screen casing performance;

D. open hole completion gravel filling sand prevention: four-layer structure is complete, removes analogue perforation eyelet, in simulation borehole wall sleeve and analog casing annular space, fills reservoir sand, between screen casing and analog casing, fills gravel, evaluates open hole completion gravel bed performance.

The experimental technique of sand control screen Performance Detection experimental provision is as follows:

1) close the valve of main tank body liquid outlet, preparing experiment displacing fluid, clear water or oil or both mixed liquors for displacing fluid;

2) put into sand control completion mode filling reservoir sand and the gravel that screen casing to be evaluated basis will be simulated;

3) turn on pump, is full of displacing fluid in advance by main tank body, covers top cover fastening;

4) open the valve of main tank body liquid outlet, be adjusted to and specify pumping rate to start experiment, and open experimental data real-time acquisition system, every a sand production rate of 5-10 minute record;

5) displacement is stable gradually to screen casing pressure at both sides, closes pump and stops real time data acquisition, records final sand production rate;

6) cleaning experimental provision, takes out reservoir sand and gravel cleaning experiment device;

7) carry out data processing and interpretation of result.

As shown in Figure 7, on the semilog screen analysis curve of practice ground layer sand, find the point of the wide correspondence of screen casing maximum seam used, make thus horizontal line crossing with the longitudinal axis, intersection point numerical value is and can passes through the reservoir sand percent by volume of screen pipe opening, if for example using certain reservoir sand tests, using the maximum seam of screen casing wide is 0.25mm, in experiment, can account for 16% of experiment reservoir sand cumulative volume by screen casing reservoir sand volume, can calculate permission sand production rate according to this numerical value, and then calculate the evaluation index of sand block performance, for the evaluation of screen casing performance, the horizontal ordinate of reservoir sand semilog screen analysis curve is logarithmic coordinate, can observe more significantly like this grain diameter characteristic of reservoir sand, in figure, horizontal ordinate is reservoir sand particle diameter, ordinate is tired heavy number percent.

As shown in Figure 8, under identical experiment condition, only changing different screen casings tests, carry out data processing and obtain displacement pressure reduction curve over time, can calculate thus screen casing Performance Evaluating Indexes, for the evaluation of screen casing performance, displacement pressure reduction refers to the outer internal pressure differences of screen casing, between described main tank wall and simulation borehole wall sleeve, the pressure at two places of main tank body liquid outlet place poor, in figure, horizontal ordinate is the displacement time, ordinate is displacement pressure reduction.

A kind of sand control screen Performance Evaluating Indexes, described evaluation index comprises: the trafficability performance evaluation index of the ability that a. passes through for quantitative evaluation screen casing permission resident fluid; B. for the sand block Performance Evaluating Indexes of the reservoir sand ability that stops of quantitative evaluation sand control screen; C. resist the performance of anti-blockage evaluation index of shale, fine sand tamper blocking ability for quantitative evaluation sand control screen; D. for the comprehensive performance evaluation index of the combination property of the different screen casings of quantitative evaluation.

Described sand control screen method of evaluating performance is the evaluation index of calculating respectively sand block performance, trafficability performance and the performance of anti-blockage of sand control screen according to experimental result data, then set rational weight coefficient for each evaluation index, calculate the quality of comprehensive function index index reflection screen casing three aspects: overall performance, calculate the balanced intensity of balanced index reflection properties, and then calculate integrated performance index, complete the performance evaluation contrast under the same conditions of different screen casings, its concrete evaluation method is as follows:

(1) screen casing trafficability performance evaluation method

The present invention uses screen casing trafficability performance evaluation index S _lcharacterize the trafficability performance of screen casing.With the composite permeability k of sand control screen _scharacterize its trafficability performance, screen casing both sides pressure reduction and the data on flows in the each moment obtaining according to experiment, calculate corresponding permeability and be:

$k_{\mathrm{si}}=\frac{q_i\mathrm{\&mu;}}{{2\mathrm{\&pi;L}}_s{\mathrm{\&Delta;P}}_i}\&CenterDot;\ln \frac{d_{\mathrm{so}}}{d_{\mathrm{si}}},$ Formula 1;

Wherein, μ is the viscosity of experiment fluid, L _sfor the effective length of experiment screen casing, d _sofor experiment screen casing external diameter, d _sifor testing sieve bore, q _ibe the i moment by the flow of screen casing, Δ P _ibe the inside and outside both sides of i moment screen casing pressure reduction, k _siit is the permeability of i moment screen casing;

Described screen casing composite permeability k _sfor the initial permeability k of screen casing _s0with the mean permeability k in experimentation _saaccording to coefficient X _kweighted mean value, its computing formula is:

K _s=k _s0x _k+ k _sa(1-X _k), formula 2;

$k_{\mathrm{sa}}=\frac{1}{N}\&CenterDot;\underset{i}{\overset{N}{\mathrm{\&Sigma;}}}{k}_{\mathrm{si}},$ Formula 3;

Wherein, the number of test points that N is experimentation, k _s0for the initial permeability of experiment screen casing, k _safor the mean permeability of screen casing in experimentation, X _kfor weighted mean coefficient, get X _k=0.5;

For the ease of the trafficability performance contrast of multiple screen casing, the present invention proposes many screen casings trafficability performance index computing formula and is:

$S_{l\left(j\right)}=\frac{k_{s\left(j\right)}}{k_{s\max }},$ Formula 4;

Wherein, k _{s (j)}be the composite permeability of j screen casing, k _smaxfor the composite permeability maximal value of whole screen casings, S _{l (j)}it is the trafficability performance evaluation index of j screen casing;

(2) screen casing sand block method of evaluating performance

The present invention uses screen casing sand block Performance Evaluating Indexes S _dcharacterize the sand block performance of screen casing.Described screen casing sand block Performance Evaluating Indexes S _dcomputing formula is:

$S_d=\frac{V_t\&CenterDot;R-V_s}{V_t\&CenterDot;R},$ Formula 5;

Wherein, V _sfor passing through the reservoir sand cumulative volume of screen casing, V in experiment _tby in experiment the cumulative volume of use reservoir sand, R was for allowing sand ratio;

(V in this evaluation index computing formula _tr) for allowing sand production rate, (V _tr-V _s) may be by screen casing in the reservoir sand that uses for experiment but there is no the reservoir sand volume of output, the index calculating is between 0-1, and the larger expression screen casing of this desired value sand block performance is better;

Allowed sand than referring to the scale-up factor that is less than testing sieve management in the reservoir sand that experiment is used and thinks the shared cumulative volume of reservoir sand volume of filtering accuracy, it can analyse curve according to stratum sand sieve, reservoir sand volume is tried to achieve with screen casing ideal filtering accuracy;

(3) screen casing performance of anti-blockage evaluation method

The present invention uses screen casing performance of anti-blockage evaluation index S _kcharacterize the performance of anti-blockage of screen casing.The displacement pressure reduction of sand control screen refers to the pressure differential that screen casing is outside and inner, can reflect the quality of screen casing performance of anti-blockage; Described screen casing performance of anti-blockage evaluation index S _kfor displacement pressure reduction mean value and the ratio of initial displacement pressure reduction, its computing formula is:

$S_k=\frac{P_0}{\stackrel{\&OverBar;}{P}},$ Formula 6;

Wherein, P ₀for initial displacement pressure reduction, the mean value of front certain a period of time or some data points in desirable experimentation,

for the average displacement pressure reduction in whole evaluation time;

S _k>=1 represents that screen casing does not exist blockage problem, S _k< 1 represents that screen casing exists blockage problem; S _klarger, represent that performance of anti-blockage is better, S _kless, represent that performance of anti-blockage is poorer;

(4) screen casing comprehensive performance evaluation method

The present invention uses screen casing comprehensive performance evaluation index S to characterize the combination property of screen casing.In order to characterize the quality of screen casing overall performance, the present invention proposes screen casing functional parameter S ₁, being defined as the weighted mean value of trafficability performance index, sand block performance index and performance of anti-blockage index, its computing formula is:

S ₁=W _ks _k+ W _ls _l+ W _ds _d, formula 7;

W _k+ W _l+ W _d=1, formula 8;

Wherein, W _kfor screen casing performance of anti-blockage evaluation weight coefficient, recommend W _k=0.4; W _lfor screen casing trafficability performance evaluation weight coefficient, recommend W _l=0.3; W _dfor screen casing sand block performance evaluation weight coefficient, recommend W _d=0.3;

Well behaved screen casing not only requires the weighted mean value of trafficability performance, sand block performance, performance of anti-blockage to want high, but also requires above-mentioned three performance relative equilibriums of screen casing, and the present invention proposes the balanced index S of screen casing thus ₂for:

S ₂=| S _k-S _l|+| S _k-S _d|+| S _l-S _d|, formula 9;

The functional parameter S of screen casing ₁larger, balanced index S ₂less, the combination property of screen casing is better, therefore proposes described screen casing comprehensive performance evaluation index to be:

S=S ₁-S ₂, formula 10;

Wherein, the comprehensive performance evaluation index S of screen casing is larger, and the combination property of screen casing is better.

Claims (1)

1. a sand control screen comprehensive performance detection experimental device, is characterized in that, comprises airtight main tank body, simulation borehole wall sleeve, analog casing, analogue perforation eyelet and fastening pull rod; Dismountable simulation borehole wall sleeve and analog casing are all nested in airtight main tank body, are positioned at the axle center place of airtight main tank body; Analogue perforation eyelet is assemblied in the eyelet of simulation borehole wall sleeve and analog casing; Be connected for the fastening pull rod of fastening main tank body and the top cover of main tank body and support base; Described sand control screen comprehensive performance detection experimental device is also provided with shunt volume system, constant current liquid-supplying system, flow real-time monitoring system, sand production rate monitoring system and pressure real-time acquisition system; Described airtight main tank body is cylindric, and it is made up of top cover, sidewall and support base; Top cover top is provided with 2 vent ports and 4 assembling suspension ring; Sidewall outside is provided with 8 inlets, and inlet is divided into two-layer up and down, and every one deck is made as 4, is uniformly distributed in the surrounding of sidewall; Support base top has 4 fitting recess, and lower central place is provided with a liquid outlet, and support base is also provided with 7 pressure taps; Airtight main tank body and connected all parts are all tightly connected; Described simulation borehole wall sleeve and analog casing are the steel cylinder with multiple eyelets; Described analogue perforation eyelet is the plastic tubulature that pliability is good; Described fastening pull rod is Steel Bolt; Described shunt volume system is the part flow arrangement with 1 inlet and 8 liquid outlets, is connected respectively with the liquid outlet of constant current liquid-supplying system and the inlet of main tank body; Described constant current liquid-supplying system comprises fluid reservoir and constant flow pump, is connected with the inlet of main tank body by shunt volume system; Described flow real-time monitoring system comprises flowmeter and data acquisition computer, and flowmeter is connected with collection computer, and flow real-time monitoring system is connected with the liquid outlet of main tank body; Described sand production rate monitoring system is the sand collector with transparent collection sand graduated cylinder, is connected with the liquid outlet of main tank body; Described pressure real-time acquisition system comprises 7 pressure transducers, is separately positioned between 1, main tank body liquid outlet place, main tank body cylinder side wall and simulation borehole wall sleeve 3 between 3, simulation borehole wall sleeve and analog casing; Described sand production rate monitoring system is cylindric sand collector, comprises cylinder shell, sand collector liquid outlet, filter sand net back-up ring, filter sand net, taper shell, sand collector support, sand collector spigot, valve, spigot pipe nipple, collection sand graduated cylinder and sand collector inlet; Described filter sand net is circular filter screen; Described taper shell is coniform, and lower end and spigot join; Valve is conventional pipeline valve; Described collection sand graduated cylinder is for being with graduated transparent organic glass cylinder; Described sand collector inlet is the outwardly directed one section of pipe of taper shell, is connected with the liquid outlet of main tank body.

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