36results about How to "Avoid stuck pipe accidents" patented technology

The invention relates to a drilling well control parameter intelligent monitoring system which comprises a monitoring part for drilling fluid cycling volume, a monitoring part for drilling fluid inlet and outlet flow, a monitoring part for drilling fluid inlet density, outlet density, drilling temperature, outlet natural gas, and H2S concentration, a monitoring part for wellhead pitshaft flowing fluid level and table torque, and a collection instrument part. All the signals are transmitted into the collection instrument to be collected through an RS485 network cable; after data processing is carried out, the data is transmitted to a drill floor parameter display device and a central station host computer through a wireless data transmission device; the data storage, display and print are carried out by the host computer, and the data is simultaneously uploaded into a data platform processor of an upper-level command center; finally, remote control realtime processing and monitoring are carried out on all the well control parameters of all the drilling crews. The intelligent monitoring system has the beneficial effects of realizing omnibearing, long-distance and timely drilling well control, safe production, and playing better role in preventing the occurrence of accidents such as well kick, loss circulation, blow-out, etc.

The invention discloses a compound type vegetable oil lubricating agent for a drilling fluid and a preparation method thereof. The compound type vegetable oil lubricating agent for the drilling fluid with favorable oiliness, no toxicity, low fluorescent level and favorable bearing and thermostabilized performance is prepared by taking a vegetable oil leftover which is low in price and easy to obtain, lauryl sodium sulfate, sbane 80, sodium carboxymethylcellulose, polyvinylpyrrolidone and the like as main raw materials, adding a solid lubricating agent which is graphite or serpentine and usinga simple and environment-friendly production method, so that not only the production cost is greatly reduced, but also any toxic and harmful action on the environment is not generated in the production process. The compound type vegetable oil lubricating agent for the drilling fluid is not only applied to drilling, but also can be applied to producing wells, can effectively inhibit the hydrous expansion of mud shale, consolidate the well wall and prevent the sticking accidents and is especially suitable for industrial production on a large scale.

The invention relates to a three-dimensional waterpower vibrator for petroleum drilling, and belongs to the technical field of design of petroleum drilling tools. The three-dimensional waterpower vibrator is composed of a flow control valve, an axial vibrator, a filtering connector, a screw motor power connector and a hydraulic impulse generator. The three-dimensional waterpower vibrator is characterized in that the flow control valve is used for adjusting flow and speed of slurry flowing into the vibrator, the axial vibrator is used for generating displacement upwards along the axial direction, the filtering connector is used for filtering thick slurry components, certain differential pressure is formed in the screw motor power connector by the slurry entering the vibrator to push a rotor structure in a screw motor to rotate and eccentrically vibrate, and the hydraulic impulse generator generates vibration in the circumferential direction through changes of open area circulation between a stationary ring and a moving ring of a PDC thrust bearing. Through three-dimensional vibration simultaneously generated in the axial direction and in the circumferential direction, large well displacement and frictional resistance between a drill column and a well wall of a horizontal well can be effectively overcome, torque between the drill column and the well wall is reduced, jamming of a drilling tool is avoided, and the three-dimensional waterpower vibrator has the advantages that drilling efficiency is remarkably improved and drilling cost is reduced.

The invention discloses a device for drilling minimal borehole on one coiled tubing side with ultra-short radius, which comprises a guider, a flexible transmission shaft, a driving motor and a bit. The flexible transmission shaft is arranged inside the guider, the bit is arranged at the output end of the flexible transmission shaft, and the driving motor is arranged at the input end of the flexible transmission shaft. The flexible transmission shaft includes more than three transmission sections which are connected with each other through ball heads, and the transmission sections are in surface contact with the ball heads. The invention increases the axial area of the flexible transmission shaft by using the ball heads to connect the transmission sections of the flexible transmission shaft and designing the surface contact between the transmission sections and the ball heads, thus prolonging the service time of the flexible transmission shaft and improving the device stability.

The invention relates to a multi-functional drilling tool assembly used for complex formations and a drilling method thereof. The drilling tool assembly comprises a drilling assembly, a detection assembly used for detecting inside of a hole, a hole wall restoration assembly used for restoring a hole wall, a drilling tool unlocking assembly used for unlocking a drilling tool, a control host and a delivery robot. The drilling assembly is used to drill and sample rubbles. The delivery robot can be arranged on the outer wall of a drilling rod column in an upward and downward sliding manner. The detection assembly is arranged on the carrying robot and moves up and down along the outer wall of the drilling rod column alongside the delivery robot. The control host is electrically connected with the detection assembly and the delivery robot. The multi-functional drilling tool assembly has evident many advantages such as drilling and sampling efficiency, high stratum adaptability and high automation degree. The detection assembly can drill and sample in complex formations while detecting the condition of the inside of the hole, thereby offering scientific, accurate and comprehensive technical parameters and information for accurate judgment and processing of hole-drilling accidents.

The invention discloses an automatic mast angle adjustment device for a core-drilling machine, relating to the technical field of core-drilling machines. The device is provided with a tilt sensor. The tilt sensor sends the acquired drilling angle signal to a programmable controller, the programmable controller computes the deviation between the current angle and the preset angle through the internal control programs, and if the deviation exceeds the preset angle deviation range, the programmable controller sends a control signal to a solenoid valve of a hydraulic leg and a support oil cylinder acts. The device has the benefits of being convenient to install and use, being capable of automatically adjusting the angle of the mast and keeping the angle of the mast in the required drilling angle deviation range all the time.

The invention discloses a petroleum drilling winch. The petroleum drilling winch comprises a roller; two sides of the roller are symmetrically connected with power devices and brakes in sequence from near to far; each power device is connected with the roller through a clutch, and includes a transmission; one ends of the transmissions are connected with the clutches, and the other ends of the transmissions are connected with driving motors; the driving motors are alternating-current variable frequency motors with two discharge ends; and the other ends of the driving motors are connected with the brakes. The petroleum drilling winch overcomes such problems as large device size, complex braking and weak safety in the prior art, and realizes the purposes of simple overall structure, simple braking and high safety.

The invention discloses a seabed multi-point-location percussion drilling coring miniature drilling rig carried by a submersible vehicle. The drilling rig comprises a first hydraulic motor, a gearbox,a percussion rotation device, a drilling tool connection and detachment device, a drilling tool storage device and drilling tools. The first hydraulic motor, the gearbox, the percussion rotation device and the drilling tool connection and detachment device transmit power in sequence. The power is transmitted to the drilling tools through the drilling tool connection and detachment device. The drilling tool connection and detachment device can select one drilling tool from the drilling tool storage device for connection and can detach the drilling tool which completes coring and enable the detached drilling tool to enter the drilling tool storage device. The seabed multi-point-location percussion drilling coring miniature drilling rig carried by the submersible vehicle is carried by the submersible vehicle, and can implement repeated multi-point-location coring and storage during one time of diving into the sea, and the economical efficiency of seabed operation is obviously improved; and the flexibility of seabed sampling operation is improved, and the drilling rig can be suitable for sampling seabed mountains and the seabed surface at the same time. During percussion drilling sampling with the seabed multi-point-location percussion drilling coring miniature drilling rig carried by the submersible vehicle, the efficiency and the effect of operation of hard rock coring are effectively improved, and meanwhile, the accident that a drilling bit gets stuck is effectively avoided.

The invention relates to the technical field of rock drilling equipment, in particular to an anti-borer-clamping hydraulic control system and rock drilling equipment. The anti-borer-clamping hydraulic control system comprises an impact control module, a propelling pressure control module, a propelling speed control module, a variable pump, a rotation motor and a propelling oil cylinder; the impact control module comprises a first proportion reversing valve communicated with a load feedback port of the variable pump and an oil tank, and a guide control port of the first proportion reversing valve is connected with an oil inlet of the propelling oil cylinder; the propelling pressure control module comprises a third proportion reversing valve communicated with the air inlet of the propelling oil cylinder and the oil tank; the propelling speed control module comprises a guide proportion throttling valve connected between the oil tank and the oil inlet of the propelling oil cylinder, and guide control ports of the third proportion reversing valve and the guide proportion throttling valve are connected with an oil inlet of the rotation motor. The rock drilling equipment comprises the anti-borer-clamping hydraulic control system. The anti-borer-clamping hydraulic control system and the rock drilling equipment are in self-adaption with various rock strata and are matched with reasonable impact pressure, propelling pressure and propelling speed.

The cation emulsified asphalt as collapse-preventing agent for well drilling fluid consists of asphalt 20-40wt%, potassium hydroxide 4-9 wt%, ammonium cetyl trimethyl chloride 1-3wt%, industrial assistant oil 15-30wt%, acrylic acid monomer 5-8wt%, deionized water 15-30wt%, dibenzoyl peroxide 0.1-0.2wt%, ammonium epoxypropyl trimethyl chloride 5-8wt% and sorbitan monooleate. The preparation process of the cation emulsified asphalt as collapse-preventing agent includes the steps of preparation of polymer emulsion, preparation of cation asphalt emulsion and compounding of polymer-cation asphalt emulsion. The collapse-preventing agent can be compounded well to cation polymer well drilling fluid to form stable well drilling fluid with obviously improved performance.

The invention relates to the technical field of a sticking reliever for petroleum and natural gas drilling and a preparation method thereof, in particular to a low-fluorescence sticking reliever and a preparation method thereof. The low-fluorescence sticking reliever comprises mineral oil, a thickening agent, an emulsifying agent and a rapid penetrating agent, wherein the mineral oil is one of white oil and aviation kerosene; the thickening agent is one or two of organic bentonite and low-fluorescence asphalt; the emulsifying agent is at least one of OP-10, OP-30, Twain-80, SP-80, oleic acid,P-30 and P-20; and the rapid penetrating agent is sodium diethylhexyl sulfosuccinate or alkylphenol polyethoxylate ether. The sticking reliever has the advantages of rapidly and effectively solving the accidents of drill sticking, avoiding the occurrences of other underground complicated conditions (well wall collapse, well leakage, and the like) caused by the drill sticking, and achieving the purposes of shortening the drilling period and saving the drilling expense.

The invention discloses a pressure-transmitting pin snapping and fracturing automatic grouting valve float valve. The automatic grouting valve float valve is characterized in that a float valve and a valve support mechanism are mounted in a float valve joint, a valve body seat of the float valve is hinged to a valve, the elasticity of a torsion spring on both the valve and the valve body seat enables the valve to close the valve body seat when the valve is in the free state; a support bar in a valve support mechanism, through which a valve hinge mount and a valve body hinge mount, supports the elasticity of the torsion spring to enable that the valve and the valve body seat can not be closed; the valve of the float valve is in the semi-opened state to form a fluid flow passage, so that the purpose of automatic grouting can be achieved. When the pump is started after tripping, or well kick occurs in a pipe, and the force acted on the valve by fluid once the blowout slurry is reversely sprayed is larger than the tensile strength of the support bar, the support bar is snapped and fractured, and the valve, which loses the supporting force after pump stop or during well kick and blowout to be in the free state, is promptly closed under the action of the resultant force of the spring force and the like. As pressure transmitting small holes are obliquely formed in the valve, pressure of fluid inside and outside the valve after the valve is closed is transmitted.

Disclosed are anti-blocking lubricant for drilling fluid and a preparing method. The anti-blocking lubricant for drilling fluid is characterized by including the following components, by weight percentage, 97.5% of No.10 white oil, 2% of oleic acid formic ester and 0.5% of emulsifier (SOP (standard operation procedure)-80). The manufacturing method includes steps of adding 97.5% of the No.10 white oil into a reactor, slowly mixing the same until the temperature rises to 25 DEG C, then adding 2% of the oleic acid formic ester and mixing uniformly slowly as heating in a manner of controlling the temperature to be no higher than 45 DEG C and mixing time to be not less than 30 minutes, finally, adding 0.5% of the emulsifier (SOP-80) and mixing continuously for one hour while heating again and controlling the temperature to be no higher than 50 DEG C. The anti-blocking lubricant for drilling fluid is high in lubricating performance, free of fluorescence and affection on geological logging data, capable of effectively preventing blocking of a drill during drilling and filling the blank of the field in home and abroad and reduction rate of lubrication coefficient is higher than 80%.

The invention relates to the technical field of drilling in geological engineering, in particular to a drilling rod with an axial deep groove wear-resistant joint for well drilling. The drilling rod comprises a rod body, a male connector and a female connector are arranged at two ends of the rod body, and a plurality of connector unscrewing clamping grooves extending along the axial direction of the male connector and the female connector are distributed on the male connector and the female connector in the circumferential direction. A connector anti-abrasion flange is formed between every twoadjacent connector screwing and unscrewing clamping grooves and provided with wear-resistant materials or a plurality of convex spherical crown installation blind holes, the smooth wear-resistant convex spherical crowns are fixedly connected into the convex spherical crown installation blind holes, and the rod body, the male connector and the female connector are each of a through hollow structure. The drill rod can be continuously screwed or unscrewed without applying radial pressure in the tripping and drill rod screwing and unscrewing processes, no damage is caused to the surface of the connector, abrasion of the connector is only generated in a well and the wall of the well, and therefore the overall service life of the drill rod is prolonged, the probability of accidents such as drilling tools and jamming of the drill rod is reduced, and the safety of the drill rod is improved. Therefore, the working efficiency of drilling is improved and the drilling cost is saved.

The invention relates to a drilling well control parameter intelligent monitoring system which comprises a monitoring part for drilling fluid cycling volume, a monitoring part for drilling fluid inlet and outlet flow, a monitoring part for drilling fluid inlet density, outlet density, drilling temperature, outlet natural gas, and H2S concentration, a monitoring part for wellhead pitshaft flowing fluid level and table torque, and a collection instrument part. All the signals are transmitted into the collection instrument to be collected through an RS485 network cable; after data processing is carried out, the data is transmitted to a drill floor parameter display device and a central station host computer through a wireless data transmission device; the data storage, display and print are carried out by the host computer, and the data is simultaneously uploaded into a data platform processor of an upper-level command center; finally, remote control realtime processing and monitoring are carried out on all the well control parameters of all the drilling crews. The intelligent monitoring system has the beneficial effects of realizing omnibearing, long-distance and timely drilling well control, safe production, and playing better role in preventing the occurrence of accidents such as well kick, loss circulation, blow-out, etc.

The embodiment of the invention discloses a winch transmission mechanism for petroleum drilling and a winch. The winch transmission mechanism comprises a rotary drum provided with a rotary drum shaft,wherein the rotary drum is provided with a first side and a second side opposite to each other along the rotary drum shaft; emergency power is arranged on the first side of the rotary drum; a gearboxand a main motor are arranged on the second side of the rotary drum; an output shaft of the gearbox is in transmission connection with the second side of the rotary drum shaft; an output shaft of themain motor is in transmission connection with an input shaft of the gearbox; and the rotary drum shaft, an output shaft of the emergency power, the input shaft of the gearbox, the output shaft of thegearbox and the output shaft of the main motor are positioned on the same straight line. According to the winch provided by the invention, the two-gear planetary gear gearbox is adopted, the winch transmission mechanism has the advantages of small size, light weight and convenience in transportation, and moreover, automatic gear shift of the winch can be realized; and in addition, due to the design of the two-gear speed changing, the maximum load capability of the winch is ensured, and a requirement on the efficiency of the winch also can be met.

A dry hole type thermal shock rotary coring drilling tool belongs to the field of drilling tools, the drilling tool comprises a drilling tool outer pipe, an electric shock device, an electric rotary device and a sampling device, the electric shock device, the electric rotary device and the sampling device are arranged in the drilling tool outer pipe, and the sampling device comprises a drilling tool inner pipe, a second slip ring, a miniature vacuum liquid pump, a melt water conveying pipe, a water storage pipe, an ice core cutter, a hot melting drill bit and an ice core pipe. Impact rotation and hot melting drilling are combined, pollution to an ice layer caused by using drilling fluid can be avoided, and drill jamming accidents occurring in a hole are effectively avoided. The impact drilling not only enables the ice layer at the bottom of the hole to generate micro cracks, but also can transmit the heat of the hot melting drill bit into the micro cracks in a pulse form, so that the strength and cutting resistance of the ice layer are reduced, and the drilling efficiency is improved. In the drilling process, the outer pipe of the drilling tool does not rotate, and friction between the outer wall of the drilling tool and an ice layer is avoided. The melt water conveying pipe and the water storage pipe are both heated through heating wires, blockage caused by melt water freezing is avoided, and meanwhile damage to the melt water conveying pipe and the water storage pipe caused by freezing and frost heaving is prevented.

The invention relating to the field of oil well equipment discloses an intelligent drift diameter gauge. The existing drift diameter gauge is designed to be a split equal-diameter deformable drift diameter gauge, so that a drilling clamp accident caused by the deformation and diameter reduction of the casing pipe is avoided. In the prior art, the existing cylinder has an enclosed top end and the open bottom; and according to the intelligent drift diameter gauge, the cylinder has an open top end and an enclosed bottom end, so that the tool has the sedimentation cup function, so that the drilling clamping accident caused by the fallen object is avoided. A phenomenon that the drilling is stuck in the drilling work due to fallen object accumulation and deformation and diameter reduction of thecasing pipe during the working process is avoided. The risk quality accident of the well repairing and ventilation procedure for underground work is reduced; and the construction efficiency of the well operation is improved.

The invention discloses a sand-sticking preventing device for a horizontal well cable transmission hydraulic pumping tool, and a method of the sand-sticking preventing device. The sand-sticking preventing device comprises a magnetic positioning device, a perforation gun string, a bridge plug putting and setting tool and a bridge plug and a sand levee clearing tool; the sand levee clearing tool isarranged in a casing pipe and sequentially connected with the bridge plug, the bridge plug putting and setting tool, the perforation gun string and the magnetic positioning device through a cable, andthe sand levee clearing tool is powered by the cable to clear a sand levee in the casing pipe by rotating at a high speed. According to the sand-sticking preventing device, the pumping failure or drilling-sticking accident caused by sand setting in the casing pipe of a horizontal well can be effectively avoided, and thus a tool string in the casing pipe of the horizontal well is pumped safely andefficiently at the high speed.

The invention discloses a top support type automatic grouting valve type float valve. The top support type automatic grouting valve type float valve is characterized in that a float valve body is mounted inside a float valve connector, and a valve top support device is welded inside the float valve body. A valve is hinged to a valve type valve body seat of the float valve body. Elastic force of a torsional spring on the valve type valve body seat enables the valve type valve body seat to be closed by the valve when the valve is in a free state. The closing spring force for automatic closing of the valve of the valve type float valve and the force for flowing towards the inside of a tube due to the inside and outside differential pressure of fluid inside a well can be balanced by the top support device according to the principle that a top support spring has certain support force (the spring force can be adjusted by the way of changing the size of the spring). A top support rod enables the valve to be in a slightly open state all the time, a channel is formed, and the purpose of automatic grouting is achieved. When well kick or blowout happens to the inside of the tube, the valve is under the action of the fluid flowing towards the inside the tube, the top support spring is compressed by the top support rod, the top support rod retracts the inside of a top support box, the valve is closed, the purpose of a check valve is achieved, the well kick and blowout accident inside the tube is prevented, and the defect that automatic grouting can not be achieved by an existing valve type float valve is overcome.

The invention discloses a pressure-transmitting supporting automatic grouting valve float valve. The automatic grouting valve float valve is characterized in that a float valve is mounted in a float valve joint, a valve supporting device is welded in the float valve, a valve body seat of the float valve is hinged to a valve, the elasticity of a torsion spring on both the valve and the valve body seat enables the valve to close the valve body seat when the valve is in the free state, the supporting device balances the spring force for automatically closing the valve-type float valve according to the principle that a supporting spring has a certain supporting force (the spring force can be adjusted through changing the size of the spring) and the in-pipe flowing force generated by pressure difference inside and outside fluid in a well, and a supporting bar enables the valve to be always in the tightly open state to form a channel so as to achieve the purpose of automatic grouting. When well kick or blowout occurs in the pipe, the valve enables the supporting bar to compress the supporting spring under the action of fluid flowing into the pipe, the supporting bar retracts into a supporting box, and the valve is closed to achieve the purpose of a check valve. As pressure-transmitting small holes are obliquely formed in the valve, the pressure of liquid inside and outside the valve after the valve is closed is transmitted.

The invention discloses a drilling speed increase tool capable of forming periodic drill string axial creeping and drilling pressure fluctuation. The drilling speed increase tool comprises a shell, the upper end of the shell is sleeved with an upper joint, the lower end of the shell is connected with a lower joint, and a pressure bearing ring is in sliding and sealed connection with the upper endin a cavity of the lower joint; a stepped shaft is arranged in a cavity of the shell, the upper end of the stepped shaft is connected to the lower end of the upper joint, the lower end of the steppedshaft is connected to the pressure bearing ring, the periphery of the stepped shaft is sleeved with a disc spring set, and the two ends of the disc spring set abut against the outer side step face ofthe stepped shaft and the top end ring face of the lower joint; and a pulsating pressure generating component is fixedly installed in the middle of the cavity of the lower joint. The drilling speed increase tool can make a drilling circulating medium to form pulsating pressure with a certain pulsating cycle through the pulsating pressure generating component, the pulsating pressure is converted into the periodic axial creeping of the upper drill string and the periodic undulating drilling on a well bottom drill bit through the pressure bearing ring, the rock breaking drilling efficiency is improved, and the hard impact on the metal surface is fully avoided.

The invention discloses a laser coring drilling method and drilling apparatus for ice layer probing. The laser coring drilling method is a physical icebreaking method of non-mechanical contact type, specifically, a high energy laser beam is used to perform direct action on an ice surface and a local ice surface is heated rapidly to melt. The laser coring drilling method comprises the steps that with the rotation of a laser probe, the laser beam is directly contacted with an ice layer, an annular gap can be formed, a drilling rod is smoothly transferred to a lower level, after the drilling of around trip is finished, ice core cutting devices are used for cutting an ice core under the cooperation of steel wire ropes, and the ice core is taken to the ground surface, so that following work ofice detection and analysis is convenient to finish. The complicated process of mechanical drilling is omitted by using a laser high-energy ice-melt method, and the pollution to polar region environment is reduced without drilling fluid, bit freezing accidents are avoided, and meanwhile, the influence caused in the process of hot water drilling on the ice core shape is further avoided, and the laser coring drilling method is extremely clean ice core original shape keeping drilling method. The laser drilling method further ensures the verticality of drilling holes, an inclined hole is not generated, and the drilling apparatus is used for realizing the method.

The invention relates to a marine fracture zone stratum water-based drilling fluid system and a preparation method and application thereof in the field of oil drilling. The marine fracture zone stratum water-based drilling fluid system is prepared from the following components in parts by weight: 1000 parts of water, 50-80 parts of bentonite, 1-5 parts of a macromolecular treating agent, 60-120 parts of a temperature-resistant fluid loss agent and 20-50 parts of a flow pattern regulator. The method mainly aims at the characteristic that the well wall of the marine fracture zone stratum is collapsed, falling blocks generated after the marine fracture zone stratum is drilled are carried away from a near-drill-bit area in time so as to achieve the purpose of well hole cleaning, rock debris or the falling blocks in an irregular well hole section in a shaft are effectively removed, the drill bit and a well bottom drilling tool are prevented from being clamped, and the drill jamming accident is avoided; and meanwhile, temperature resistance and plugging are considered, the system is kept stable under the high-temperature condition of a deep well, the safe drilling requirement is met, the drilling period is shortened, and the comprehensive drilling cost is reduced.

The invention relates to an open-hole well drilling method for drilling a shale formation, which comprises the following steps: in the drilling process, if the well wall collapses, it is judged whether the well wall collapse occurs in the shale formation; if the well wall collapse occurs in the shale formation; For muddy shale formations, a milling cone drilling tool assembly is used for well drilling, wherein the drill bit of the milling cone drilling tool assembly is a tapered milling shoe. The beneficial effect is that, in view of the well wall collapse phenomenon in the mud shale formation, the milling cone drilling tool assembly is used for open-hole drilling, which reduces the well collapse and sticking caused by the drill bit, and the problem of delineating a new wellbore is not easy to occur.

The invention discloses a protection device for preventing drill sticking of a rotary drilling rig. The main structure is a drill protection cover with a cylindrical structure, and a drill rod installation hole is opened at the top center of the drill protection cover for installing the drill rod; There are 3 drill installation operation holes and 1 drill control rod hole on the outside of the rod installation hole. The drill installation operation holes are set in three directions orthogonal to the top of the drill protection cover, which are used as drill installation process holes and drill control rod holes. to install the drill control rod; the side of the drill bit protection cover is provided with drill bit installation pin holes for installing the drill bit installation pin; the inside of the drill bit protection cover is provided with 4 buckle baffles, which are used to prevent the rotation between the rotary drilling bit and the protection device. relative rotation occurs. The invention is simple to manufacture, flexible and convenient to install, can be assembled together with the drill bit, has few restrictions, and can effectively prevent the jamming caused by the instability of the hole wall, the falling of the rock or the blocking of the top device of the drill bit by a large boulder protruding from the hole wall drill accident.

The invention provides a rotary core cutting process for high-permeability or fractured formation. The rotary core cutting process comprises the following steps: increasing displacement cycle of a pump after coring and drilling are accomplished, and not stopping a top drive or a rotary disc; not stopping the pump, discontinuously upwards lifting a drilling tool, cutting a rock core by pull force gradually generated by discontinuously upwards lifting the drilling tool, rotating and finishing a well wall by a coring drill bit, and providing a safety channel for the coring drill bit; after rock core cutting, reducing rotation speed of the top drive or the rotary disc, and continuously upwards lifting the drilling tool discontinuously until lifting the drilling tool to a safety well section. The rotary core cutting process has the beneficial effects that: the rotary core cutting process is suitable for complex well section coring, can greatly reduce working torque and tensile force borne on the drilling tool, the coring tool and the coring drill bit, can avoid a complex condition that normal drill lifting cannot be achieved as a result of frequent blocking during core cutting, can timely drill the core, analyzes data, and avoids the occurrence of a drill blocking accident.

The invention discloses an accurate simultaneous casing drilling control method for composite rock mass. The method comprises steps as follows: accurate setting-out of a drilling machine is performed, and the drilling machine and a bottom plate geologic body are firmly positioned through U-shaped ground screws; an ordinary down-the-hole hammer drilling rig which is 3-5 mm larger than the outer diameter of a simultaneous casing is adopted to drill through broken rock mass to a loose body interface; three drill pipe holes which are distributed in a 120-degree manner are drilled in the front section of a first drill pipe in the connection position with the ordinary down-the-hole hammer drilling rig, and the flowing state of air current nearby the ordinary down-the-hole hammer drilling rig is changed; as for the simultaneous casing for grouting on the loose body, the interval between casing body holes drilled in the simultaneous casing and the number of the casing body holes in the casing body section are limited. By means of the control method, accurate simultaneous casing drilling in the composite rock mass can be realized, the simultaneous casing drilling efficiency and accuracy are guaranteed, the accident rate of casing breakage in the composite rock mass is reduced, and the accident of jamming of a drilling tool in interfaces of rock mass with different qualities is effectively avoided.