Disclosure of Invention
Aiming at the defects existing in the prior art, the invention aims to provide a hydraulic injection coal leakage and permeability improvement ground well construction method, which solves the technical problems.
The scheme adopted by the invention is as follows: the construction method of the hydraulic jetting coal leakage and permeability-increasing ground well comprises the following steps of:
s1: constructing a ground well at a selected position of a target coal seam and a target area;
S2: drilling a ground well in a three-open mode to form a three-open section, wherein the three-open section comprises a first-open vertical section, a casing pipe is put in for well cementation, a second-open vertical turning section, a casing pipe is put in for well cementation, a third-open horizontal section, the casing pipe is put in for not well cementation, the position of an auxiliary coal leakage roadway is determined through drilling, and comprehensive well logging is completed when the casing pipe is put in;
s3: tunneling the auxiliary coal discharging roadway for a plurality of meters, so that the auxiliary coal discharging roadway is communicated with the three-opening section;
S4: a hydraulic jet hole is arranged in the three-opening horizontal section, a jet gun is adopted to cut, punch and form holes on the peripheral coal body of the three-opening horizontal section, and a steel sleeve is sent into the three-opening horizontal section to form a coal leakage channel;
S5: and (5) carrying out punching and well flushing operation in the well and making well completion design data.
When in use, in the step S1, the technical parameters of the well cementation process are as follows:
① The casing make-up torque must meet the relevant specification requirements, using casing hydraulic tongs, an automatic recording torque meter and adopting casing thread compound conforming to API standard;
② The surface casing must be cementing with G grade or above G grade oil well cement, the cement returns to the ground, otherwise, the cement is repaired; the pocket of the surface sleeve is less than 1m, the pressure test of the surface sleeve is more than or equal to 8MPa, and the depressurization is not more than 0.5MPa within 30 minutes; the sleeve is centered, the slurry replacing amount is accurate, and the replacement is forbidden;
③ Before well cementation construction, the compressive strength test of 48 hours is carried out on the cement for design by using site water, the compressive strength is more than or equal to 14MPa, and the chloridion test is carried out to ensure the compatibility with the cement;
④ The technical sleeve can be well cemented by using microbeads with low density, the density of cement paste is not less than 1.65g/cm < 3 >, and the cement paste is required to be raised to the ground;
⑤ 1.5-2.0m of technical sleeve pocket, the pressure test of the production sleeve is more than or equal to 10MPa, and the depressurization is not more than 0.5MPa within 30 minutes; the cement sheath cementing quality of the upper target coal seam section and the cement sheath cementing quality of more than 250m above the top plate of the upper target coal seam section are guaranteed to be good, and the phenomenon of string leakage cannot occur, namely, the cementing quality of the target coal seam section and the cement sheath cementing quality of more than 250m above the target coal seam section reach the standard above qualification;
⑥ The compressive strength of the cement stone with the open guide pipe is more than or equal to 3.5MPa for 24 hours, and the compressive strength of the cement stone with the open guide pipe is more than or equal to 7MPa for 24 hours. The cement paste thickening time is more than or equal to the cementing operation time (the total time from the preparation of cement paste to the closing of a well and the waiting for solidification) +1h.
The casing pipe setting technical requirements are as follows:
① The running speed of the casing is strictly controlled and is generally not more than 0.46m/s. In the process of casing running, the midway pause is reduced as much as possible, and the down-hole resting time of the casing is shortened. The operation of casing is stable, and the violent brake and the violent release are forbidden.
② The sleeve should be moved up and down in the grouting process to prevent the sleeve from sticking, the moving distance is not less than 2m and the sleeve is practically moved.
③ After the casing is put down, well filling drilling fluid, opening a pump with small discharge capacity, after a circulating pump pressure is established by jacking, circulating well washing with large discharge capacity by more than 2 times until no mud cake and rock debris are arranged on a vibrating screen, and the performance of the drilling fluid reaches the requirement of well cementation construction, then carrying out subsequent construction.
④ After the impact pressure is regulated for 2-3 min, the pressure is released, the pressure difference of the hydrostatic column inside and outside the pipe is 1-1.5 MPa, and the pipe is waiting for coagulation. If the downhole back pressure valve is sealed, the casing is opened to be condensed; otherwise, guan Jingbie is needed to wait for condensation and send special personnel to monitor.
⑤ During the well dredging, the well blocking section is scratched, high-quality drilling fluid is adopted for washing the well with large discharge capacity, the well wall is ensured to be stable, the well is clean, the friction resistance is small, the leakage phenomenon is avoided, and the oil gas channeling-up speed is ensured to be less than 10m/h.
Preferably, in the step S1, a ground well is constructed at a selected position of 100m non-fault around a three-open horizontal coal section, wherein the burial depth of the target coal seam is 400-500m, the coal quality is three types or less of structural coal.
Preferably, in the step S2, a vertical section is opened, a surface casing is put in, well cementation cement is returned to the ground, and a wellhead is established; the second-opening vertical turning section is provided with a second-opening sleeve to seal the upper leakage layer and the water layer, so that conditions are provided for the next-opening safe drilling, and the cementing cement is required to return to the ground; the third opening is the inclined drilling section along the coal seam, the drilling section is downwards put in, and the well is not fixed.
Preferably, in step S2, the comprehensive logging includes:
Gas logging is carried out by adopting an SK-2000 logging instrument or logging instruments and gas logging equipment with the same detection capability, gas logging data comprise full hydrocarbon and methane hydrocarbon gases, and gas logging is carried out from two-way operation, so that the gas content of a coal-series stratum is monitored;
The method comprises the steps of logging rock cuttings, establishing a stratum profile according to the sampling condition of the rock cuttings, on-site sorting and summarizing a rock cuttings logging table, drawing a 1:500 section while drilling, and primarily judging and dividing the stratum;
Logging while drilling, wherein 1 drilling time point is recorded every 1m from the base rock, and 1 drilling time point is recorded at the target layer well section 0.5m, so that the buried depth and thickness of a coal bed can be conveniently judged, the gangue clamping position can be conveniently determined, the relative stability of drilling parameters can be kept, the effectiveness of the drilling parameters for reflecting the lithology of a stratum can be conveniently improved, and non-geological factors causing false drilling can be recorded.
Logging by using drilling fluid, performing full-performance measurement every 8 hours, and measuring general performance (density and viscosity) every 2 hours;
The simple hydrologic observation is carried out, and the simple hydrologic observation record work is needed to be carried out in the whole well drilling process;
The method comprises the steps of circularly observing, namely immediately stopping drilling when the drilling meets a target coal seam and is abnormal, circularly observing, measuring the density and viscosity of drilling fluid in an encrypted manner, and observing the gas display condition, the surface of a drilling fluid pool and the volume change;
Geological logging is performed during gamma-ray specific operation while drilling, when the engineering requires to drill from three times, directional constructors add natural gamma-ray while drilling, the well track is monitored in real time, and the actual drilling situation when meeting the stratum can be judged according to the change of gamma amplitude by combining gas logging, logging while drilling and cuttings logging; when a horizontal well drills in a coal seam, once the gamma amplitude is found to be abnormal, the drilling horizon of a drill bit in the well is judged by combining with other on-site logging data, the track of a well bore is adjusted in time, and the drill bit is kept to drill in the target coal seam;
And in the geophysical well logging process, logging while drilling is required to be performed on a horizontal section, gamma and magnetic positioning well logging is performed on a three-open casing, well logging requirements and times are based on a well logging task book, casing collar well logging is performed after casing cementing is performed, and the measurement items comprise natural gamma and magnetic positioning, and the depth ratio is 1:200.
Preferably, in the step S3, the three-open horizontal section and the auxiliary coal discharging roadway are located at the tail end of the three-open section, the three-open horizontal section is a straight-wall semicircular arch roadway, the anchor net rope spraying and the steel belt supporting are adopted, the anchor net rope spraying and the steel belt supporting are located at the bottom of the target coal seam, and after the position of the auxiliary coal discharging roadway is determined, the coal discharging roadway is driven for 10m, so that the coal discharging roadway is communicated with the three-open horizontal section.
Preferably, in the step S5, during flushing, the amount of flushing liquid is determined according to the volume of the horizontal well bore, and the prepared liquid amount is not less than 2 times the bore volume; when the well is washed and started by punching strength, the change of pumping pressure is observed, the displacement is controlled from small to large, meanwhile, the condition of wellhead liquid return is observed, and the punching degree is judged according to the condition; in the punching process, the pump pressure, the displacement and the liquid outlet amount are observed and recorded; the pump pressure is raised, the displacement should be adjusted in time, and the reasons are analyzed and processed, so that the pump cannot be forced to be suppressed.
Preferably, in step S2,
Preparing 60m3 bentonite slurry by using production water, adding Na2CO3 and sodium bentonite through a slurry preparation funnel according to a formula, uniformly stirring, and drilling after the drilling fluid is adjusted to meet the design requirement;
the second vertical turning section is mainly used for preventing collapse, block falling and drill burying;
and (3) preparing a sufficient quantity of KCl low solid phase drilling fluid on the ground in the three horizontal sections, and allowing drilling after the design requirement is met.
The beneficial effects of the invention are: the method can ensure smooth construction of the ground well, effectively ensure the later three-open-section hydraulic jetting coal leakage effect, improve the coal bed air permeability of the target layer, reduce the target coal bed stress, promote desorption and dissociation of gas in the coal bed, and further improve the coal bed gas yield of the ground well. Compared with the traditional ground well fracturing, the method has the advantages of remarkably eliminating high stress concentration areas, ensuring that the fracture starting cracks are not easy to close, being long in efficient extraction time and the like, and can greatly save the fund cost of the ground well. The invention has the advantages of low cost, simple operation, strong reliability and the like, and has wide application prospect in the technical field.
Detailed Description
The foregoing and other features, aspects and advantages of the present invention will become more apparent from the following detailed description of the embodiments with reference to the accompanying drawings 1-2. The following embodiments are described in detail with reference to the drawings.
Exemplary embodiments of the present invention will be described below with reference to the accompanying drawings.
The first embodiment is a hydraulic injection coal leakage and permeability-increasing ground well construction method, which comprises a target coal bed 1, a ground well 2, an auxiliary coal leakage roadway 3 and a hydraulic injection hole 4, and is characterized by comprising the following steps:
S1: constructing a ground well 2 at a selected position of a target coal bed 1 and a target area;
S2: drilling the ground well 2 in a three-open mode to form a three-open section, wherein the three-open section comprises a first-open vertical section 6, a second-open vertical turning section 7, a third-open horizontal section 8 and a well cementation by a casing, the well cementation is carried out by the casing, the well cementation is not carried out by the casing, the position of an auxiliary coal leakage lane 3 is determined by drilling, and comprehensive well logging is completed when the casing is put in;
S3: tunneling the auxiliary coal discharging roadway 3 for a plurality of meters, so that the auxiliary coal discharging roadway 3 is communicated with the three-open section;
S4: the hydraulic jet hole 4 is arranged in the three-open horizontal section 8, a jet gun is adopted to cut, punch and make holes on the peripheral coal body of the three-open horizontal section 8, and a steel sleeve is sent into the three-open horizontal section 8 to form a coal leakage channel 9;
S5: and (5) carrying out punching and well flushing operation in the well and making well completion design data.
In the second embodiment, in the step S1, the ground well 2 is constructed by constructing coal with three types and below and three horizontal coal sections with 100m non-fault selected positions around the horizontal coal sections in the depth of 400-500m of the target coal seam 1.
In the third embodiment, on the basis of the first embodiment, in the step S2, a vertical section 6 is opened, a surface casing is put in, well cementation cement is returned to the ground, and a wellhead is established; a second-opening vertical turning section 7 is provided with a second-opening sleeve to seal an upper leakage layer and a water layer, so that conditions are provided for the next-opening safe drilling, and the cementing cement is required to return to the ground; the three-way is to drill the section along the coal seam, and the three-way sleeve is put in without cementing.
When the drill is used, the diameter of the drill bit at one section is 444.5mm, the diameter of the sleeve is 339.7mm, the steel grade J55 of the sleeve is arranged, and cement returns to the ground; the diameter of the second-stage drill bit is 311.15mm, the diameter of the sleeve is 244.5mm, the steel grade J55 of the sleeve is arranged, and the cement returns to the ground; the diameter of the three-open section drill bit is 215.9mm, the diameter of the sleeve is 139.7mm, and the sleeve steel grade N80 is not well cementated.
The three drilling adopts different drilling fluids, one drilling adopts air drilling, clean water or prehydration bentonite drilling fluid to carry rock scraps, the drilling fluid is prepared for preventing collapse and leakage, and the drilling fluid takes (5-6)% bentonite+ (0.5-0.6)% sodium carbonate as a main material and takes low-viscosity polyanion cellulose, plugging agent and the like as additives; the second drilling fluid is prepared to mainly prevent collapse, block drop and burial, polymer is used to lubricate the collapse-preventing drilling fluid, the first drilling fluid plus (0.3-0.5)% polyacrylamide potassium salt plus (0.5-1)% low viscosity polyanionic cellulose plus (0.5-1)% hydrolyzed polyacrylonitrile ammonium salt plus (1.5-2)% collapse-preventing viscosity-reducing filtrate reducer plus (2-3)% extreme pressure lubricant is used to mainly, and additives such as industrial sodium hydroxide, plugging agent and the like are used to realize safe drilling and accurate landing; the three-way drilling is mainly performed in a coal seam, according to the stratum characteristics, KCl low solid phase drilling fluid, (4-6)% bentonite+ (0.3-0.5)% polyacrylamide potassium salt+ (0.5-1.0)% sulfonate copolymer filtrate reducer+ (1-1.5)% low viscosity polyanion cellulose+ (5-7)% potassium chloride+ (0.5-1)% waterproof locking agent+ (2-3)% emulsified paraffin+ (2-4)% multistage filling plugging agent+ (1.5-2.5)% nano plugging agent+ (0.5-1.5)% organic amine+ (4-8)% extreme pressure lubricant are used as main materials, and additives such as industrial sodium hydroxide, plugging agent, solid lubricant, plastic pellets and the like are used as auxiliary materials, so that the stability of the well wall is ensured, and the well is convenient to lower.
Different well cementing processes. Casing string structure (bottom-up), one open top layer casing string structure: float shoe + sleeve string + top joint; two-way technology sleeve pipe string structure: float shoe, 1 sleeve, float collar, sleeve string and joint.
To meet the production requirements of different well sections. The first section is high in drilling efficiency, the second section is safe to drill and accurately land, the third section is short, the well wall is stable, and the pipe is convenient to lower;
in a fourth embodiment, based on the first embodiment, in step S2, the comprehensive logging includes:
Gas logging is carried out by adopting an SK-2000 logging instrument or logging instruments and gas logging equipment with the same detection capability, gas logging data comprise full hydrocarbon and methane hydrocarbon gases, and gas logging is carried out from two-way operation, so that the gas content of a coal-series stratum is monitored; the method comprises the steps of logging rock cuttings, establishing a stratum profile according to the sampling condition of the rock cuttings, on-site sorting and summarizing a rock cuttings logging table, drawing a 1:500 section while drilling, and primarily judging and dividing the stratum; logging while drilling, wherein 1 drilling time point is recorded every 1m from the base rock, and 1 drilling time point is recorded at the target layer well section 0.5m, so that the burial depth and thickness of a coal bed are conveniently judged, the gangue clamping position is determined, the relative stability of drilling parameters is kept, the effectiveness of the drilling parameters for reflecting the lithology of a stratum is improved, and non-geological factors causing false drilling are recorded; logging by using drilling fluid, performing full-performance measurement every 8 hours, and measuring general performance (density and viscosity) every 2 hours; the simple hydrologic observation is carried out, and the simple hydrologic observation record work is needed to be carried out in the whole well drilling process; the drilling is stopped immediately when the drilling meets the target coal seam 1 and the abnormality is found, the drilling fluid density and the viscosity are measured in an encrypted manner, and the gas display condition, the drilling fluid pool surface and the volume change are observed; geological logging is performed during gamma-ray specific operation while drilling, when the engineering requires to drill from three times, directional constructors add natural gamma-ray while drilling, the well track is monitored in real time, and the actual drilling situation when meeting the stratum can be judged according to the change of gamma amplitude by combining gas logging, logging while drilling and cuttings logging; when a horizontal well drills in a coal seam, once the gamma amplitude is found to be abnormal, the drilling horizon of a drill bit in the well is judged by combining with other on-site logging data, the track of a well bore is adjusted in time, and the drill bit is kept to drill in the target coal seam; and in the geophysical well logging process, logging while drilling is required to be performed on a horizontal section, gamma and magnetic positioning well logging is performed on a three-open casing, well logging requirements and times are based on a well logging task book, casing collar well logging is performed after casing cementing is performed, and the measurement items comprise natural gamma and magnetic positioning, and the depth ratio is 1:200.
When the method is used, ① meteorological logging is performed at the bottom of each drilling, 1% concentration methane gas (or calibration natural gas) is injected for checking the retention time, the repetition error and the separation degree; the tightness of the pipeline is checked every shift by injecting methane gas (or calibration natural gas) with concentration of 1% at the inlet of the wellhead gas pipeline. The check record is stored as a measurement while drilling data.
② The fourth system and the recent system of the cuttings logging do not drag for sand samples, but the interface of the bedrock must be judged, 1 sand sample is dragged for every 2m after entering the bedrock, and 1 sand sample is dragged for every 5m after horizontal drilling to a second 1 coal bed due to high drilling speed, and the stratum profile is established.
③ Logging is carried out once every 8 hours during drilling, and full performance measurement is carried out; the general properties (density, viscosity) were measured every 2 h.
④ The simple hydrologic observation records the drilling fluid consumption once every 2 hours of drilling, records the drilling fluid consumption once every 1 hour after entering the lower stone box group, and also observes the drilling fluid consumption when the drilling fluid consumption is less than 1 hour but more than 30 minutes.
In the fifth embodiment, based on the first embodiment, in the step S3, the three-open horizontal section 8 and the auxiliary coal discharging roadway 3 are located at the end of the three-open section, the three-open horizontal section 8 is a straight-wall semicircular arch roadway, the anchor net rope spraying and the steel belt supporting are adopted, the anchor net rope spraying and the steel belt supporting are located at the bottom of the target coal seam 1, and after the position of the auxiliary coal discharging roadway 3 is determined, the coal discharging roadway is driven for 10 meters again, so that the coal discharging roadway is communicated with the three-open horizontal section 8.
In the sixth embodiment, based on the first embodiment, in the step S5, the amount of the flushing liquid is determined according to the volume of the horizontal well bore hole during flushing, and the prepared liquid amount is not less than 2 times the bore hole volume; when the well is washed and started by punching strength, the change of pumping pressure is observed, the displacement is controlled from small to large, meanwhile, the condition of wellhead liquid return is observed, and the punching degree is judged according to the condition; in the punching process, the pump pressure, the displacement and the liquid outlet amount are observed and recorded; the pump pressure is raised, the displacement should be adjusted in time, and the reasons are analyzed and processed, so that the pump cannot be forced to be suppressed.
In a seventh embodiment, based on the first embodiment, the method for maintaining and treating drilling fluid includes:
Preparing 60m3 bentonite slurry by using production water, adding Na2CO3 and sodium bentonite through a slurry preparation funnel according to a formula, uniformly stirring, and drilling after the drilling fluid is adjusted to meet the design requirement; and during drilling, solid control equipment is fully utilized to remove drilling cuttings, and production water is used for adjusting the viscosity cutting. And after drilling, the well is fully washed, the drilling fluid performance is adjusted, and smooth casing running and well cementation construction is ensured.
The second vertical turning section 7 is mainly used for preventing collapse, block falling and drill burying;
① And diluting the drilling fluid in the first step with clear water, adding a treating agent according to the formula requirement, and adjusting the performance of the drilling fluid with ammonium salt to meet the design requirement, and then performing the second step.
② And (3) replenishing polyacrylamide glue solution during drilling, improving the coating inhibition capability of drilling fluid, regulating pH by NaOH, controlling viscosity by ammonium salt, and regulating viscosity.
③ In the inclined shaft section drilling process, a lubricant is properly added according to the friction torque change condition, so that friction and torque are reduced, and sticking is prevented.
④ Various treating agents are timely supplemented according to the formula of the drilling fluid at the well section in the drilling process, the effective content of the treating agents is maintained, and various properties of the drilling fluid are strictly controlled to meet the design requirements. The vibrating screen, the sand remover, the mud remover and the like must be synchronously operated with the drilling pump, and the inferior solid phase content and the low-density solid phase in the drilling fluid are strictly controlled.
⑤ The centrifuge is fully used as required. In the drilling process, the drilling is started and started periodically for short time, so that the cleaning of a borehole is ensured, the viscosity and the cutting force of drilling fluid are properly improved after drilling is finished, the suspending capacity of the drilling fluid is further improved, and the smooth construction of casing running and well cementation operation is ensured.
⑥ To prevent lost circulation, a certain amount of plugging agent is reserved.
And a three-open horizontal section 8 for preparing a sufficient quantity of KCl low solid phase drilling fluid on the ground.
① After reaching the design requirements, the drill is allowed to be started.
② The vibrating screen, the sand remover, the mud remover and the drilling pump are required to run synchronously, the inferior solid phase and the low-density solid phase content in the drilling fluid are strictly controlled, and the centrifugal machine is fully used as required.
③ Various treating agents can be supplemented in a dry agent form during drilling, and the API filtrate loss of the drilling fluid is maintained to meet the design requirement. Maintaining proper viscosity and cutting to raise the suspending and carrying capacity of drilling fluid, and adding temporary plugging agent in reasonable grading during drilling to raise the plugging performance of the filter cake to the maximum.
④ And (3) timely supplementing a lubricant according to the downhole friction, and keeping the friction coefficient of the mud cake to be less than 390.05 so as to prevent sticking.
⑤ The solid control equipment is fully utilized to remove harmful solid phase mixed in the drilling fluid, and the sand content is reduced (the sand content is less than 0.5%).
When the device is used, the two deflecting sections ① accurately land, according to the occurrence condition of a coal reservoir in a mining area, on one hand, the deflecting landing section adopts a BlackStar EM-MWD (electromagnetic wireless measurement while drilling) or near-bit geosteering system (parameters such as well angle, azimuth angle, tool face angle, gamma and resistivity) to match with a large-angle pilot hole, and the current real drilling bit information is timely and accurately predicted by combining formation parameters, measurement while drilling parameters and logging parameters in the drilling process, so that track control and accurate landing are realized; and on the other hand, a flexible drilling tool assembly is adopted, and a phi 127mm heavy drill rod is used, so that 55 heavy drill rods are added to the position above the deflecting point in a flip-chip manner, and the effective transmission of the drilling pressure is ensured. The drilling mode of each drill rod is optimized according to the build-up rate of track control, sliding drilling is combined with compound drilling, so that the dogleg degree is even, the whole well track is smooth, and friction torque is reduced. The three horizontal sections are provided with flexible drilling tool assemblies, the well is drilled by using the well drilling tool assemblies, the horizontal section drilling tool assemblies are put down, when in compound drilling, the top drive is slowly rotated or the rotary table is tried to drill, the torque change is closely observed, if the torque is too large, the rotary table cannot be continuously rotated, and the screw drilling tool is adopted for sliding drilling. The method has the advantages that the measured data are processed in time, the well bottom data are predicted accurately, the drilling parameters and the well path are adjusted in time, the well deviation and the azimuth are prevented from being adjusted greatly, and the friction is reduced as much as possible. The next short trip is performed every 100m of drilling, if necessary, a complex well section is started or the well is started above the casing shoe, and if the underground complex well is started every 40-50 m of drilling, the next short trip is performed. When the casing pipe is produced, a proper amount of glass bead balls and a roller casing pipe centralizer can be added according to the underground condition, so that the sliding friction is converted into rolling friction, and the smooth construction of the casing pipe is ensured.
The three-open-hole deep structure is shown in table 1:
The performance requirements of the well cementation cement are shown in table 2:
the requirements for the drilling fluid of the well sections are shown in Table 3:
the casing string and casing performance requirements are shown in tables 4 and 5:
design log entries see for oneself table 6 shows:
the logging design data includes: (1) a completion wellhead is shown in fig. 2; (2) Other related requirements are carried out according to the standards of drilling and production equipment wellhead devices and production trees (GB/T22513-2008) of the oil and gas industry. And (3) timely carrying out sleeve cap loading after completion, and marking the well number. (4) The top surface of the production casing collar must be horizontal, the levelness is less than or equal to 2mm, and the height above the ground (the top of the production casing collar is flush with the ground) is required to be less than 0.3m. And (5) pulling the guy rope to fix the wellhead, so as to ensure the stability of the wellhead. (6) Any part of the wellhead is disassembled and replaced, and pressure needs to be tested again to ensure the tightness of the wellhead.
The above description is only for the purpose of illustrating the invention, and it should be understood that the invention is not limited to the above embodiments, but various modifications consistent with the idea of the invention are within the scope of the invention.