RU2188299C2 - Core sampler - Google Patents

Abstract

FIELD: mining, particularly, devices for well coring. SUBSTANCE: core sampler has body with coupling, rock cutting tool, sub consisting of external sleeve secured to body and internal sleeve connected by means of nipple with drill string. External and internal sleeves are engageable with each other with the help of splines made on them and reciprocating relative to each other along their axes. Centralizer is secured to internal sleeve. Installed on centralizer is radial bearing, thrust bearing and plug-like radial valve. Inner barrel is installed by means of core catchers on support provided with thrust ball bearing and seal. Inner barrel upper end is installed on radial ball bearing and engageable with thrust ball beating, and plug-like radial valve which closes or opens radial windows made on inner barrel which is provided with ejectors whose channels are communicated with radial windows. Inner barrel accommodates chamber with pushing plunger. Made on pushing plunger is axial channel, and head is secured which is engageable with seal and core. Invention ensures production of isolated core coated with core-insulating composition to provide for more accurate determination of hydrocarbon reserves. EFFECT: higher degree of recovery of representative core protected from its washing with drilling mud. 5 cl, 1 dwg core-insulating composition

Description

 The invention relates to the field of mining, in particular to devices for core drilling with coring.

 Known coring shell on the application 98104205/03 for the grant of a patent for an invention, publ. 12/27/1999, in BI 9936, containing a housing with a sleeve mounted on it, a rock cutting tool, an adapter for connecting to a drill pipe string, including an external pipe mounted by means of a sleeve on the body, a centralizer equipped with a radial bearing, ejectors, a core receiver pipe installed the lower end by means of a core core body on a support, and the upper end mounted on a radial bearing, and a chamber equipped with a displacing plunger filled with a core insulating composition. This core sampling shell is equipped with a device for locking the channels of the ejectors for the period of lowering the core sampling shell to the bottom by executing a spring-loaded radial valve inside the core receiver pipe, which closes the channels of the ejectors, which eliminates the displacement of fluid from the core receiver pipe, and upon reaching the bottom and drilling starts with the inclusion of drilling fluid, which, due to the pressure force, moves the spring-loaded stem down, and the radial valve, moving down, opens the channels of the ejectors to exit the fluid from the core the receiving pipe into the discharge channel, while ensuring the unimpeded movement of the movable chamber and the movement of the core.

 However, in practice, core drilling technology does not exclude the necessary intermediate flushing of the wellbore during the launch of the coring shell before the bottom, since there is a lot of sludge in the flushing fluid in the wellbore, without which the situation often complicates the launching of the coring shell before the bottom, and therefore, the above method of locking the channels of the ejectors for the period of lowering the coring shell before the bottom does not allow these channels of the ejectors to be constantly closed with a radial valve, since during the intermediate washing of the wellbore due to the passage of the flushing fluid at high speed and at high pressure, the radial valve moves down and the ejector channels open, and the fluid contained in it is sucked out of the core pipe, resulting in a chamber with a core insulating composition freely moves to the upper part of the core-receiving pipe, therefore, the cavity of the latter under the chamber is filled with liquid in the wellbore. During the drilling period, the core being drilled enters the core receiving pipe filled with a liquid with a high sludge content, and the core is washed with this liquid, which prevents the core from moving, as a result of which the core is deformed and collapses. This disadvantage excludes the removal of an isolated core; this does not allow determining the reliability of hydrocarbon reserves in the ongoing drilling, as it does not allow accurately determining the position of productive formations. As a result of a significant drawback, this method of locking the ejector channels with a radial valve is not effective.

 The purpose of the invention is to carry out a full removal of a representative core protected from washing with drilling mud and covered with a core insulating composition during sinking, which allows more accurate determination of the location of productive formations and ensures reliable estimation of hydrocarbon reserves.

 This goal is achieved by the fact that a core sample containing: a body with a clutch mounted on it; rock cutting tool; an adapter for connecting to a drill pipe string, including an outer pipe fixed by means of a sleeve to the body; a centralizer equipped with a deep groove ball bearing; ejectors; a core receiver pipe installed at its lower end by means of a core explorer body on a support, and its upper end mounted on a deep groove ball bearing, and a chamber equipped with a propellant plunger filled with a core insulating composition, according to the invention, the adapter further comprises an internal nozzle adapted for reciprocating movement along its axis relative to the outer pipe, connected by means of a nipple to the drill pipe string, the centralizer is fixed to the inner pipe and with filled with a thrust bearing, a deep groove ball bearing mounted on the centralizer is double row with bulk balls in a sealed housing filled with grease, a thrust bearing mounted on a centralizer is made with bulk balls in a sealed housing filled with grease, the core receiving tube with its upper end mounted on a radial double row ball bearing, interacts with its end face with a thrust bearing and is equipped with a ring, ejectors are mounted on the said ring, on the lower end e centralizer has a plug-shaped radial valve made in a rubber-metal version, equipped with a double-row ball bearing and with the possibility of reciprocating movement along the axis of the core-receiving pipe, for sealing the cavity of the core-receiving pipe, a self-sealing rubber element with a pressure ring is provided, the core-case is made conical on the inside and a radial annular groove is made on its lower supporting protrusion, while the support has an end annular pr the point and is equipped with fixing screws that interact with a radial annular groove made on the lower support protrusion of the core-raiser body, and on the lower part of the support there is a platform for an oil seal, which is fixed by a pressure ring, a tip is attached to the lower end of the displacer-protector, which interacts with the oil seal and drilled core and serves as a leveler core insulating composition on the core pipe.

 The radial ball bearing is made in the form of a block consisting of an inner cage made with an end cage, an outer cage made in the middle with a two-way end cage, an end cage fixed to the inner cage, and balls are laid between the cages, and ring grooves are made on the end outer cages in which seals are installed that interact with the outer cage, while the outer casing has annular grooves in which seals are installed that interact with the core opriemnoy pipe.

 The thrust ball bearing is made in the form of a block consisting of an upper cage, a thrust cage, and balls are laid between the cages, the cages interacting with each other by means of the seals provided with them, the cages being fixed to each other and between the gaskets by a ring, while the thrust cage interacts with the end of the core receiving pipe .

 The displacer plunger is made with an axial channel communicating with the cavity of the chamber, with holes communicating the axial channel with the cavity of the core core body.

 The tip has an axial channel, which is equipped with a plug.

 An analysis of the patent literature showed that there are no known technical solutions in which there is a combination of features that distinguish the claimed solution from the prototype. Thus, the set of features of the proposed solution ensures the achievement of the goal and meets the criteria of "novelty" and "significant differences".

 The drawing shows a core sample during the period of launching and lifting it in the well, when the radial windows made on the upper part of the core-receiving pipe are closed by cork-shaped radial valves.

 A core sample contains: a housing 1 with a coupling 2 fixed to it and a discharge channel 3; rock forming tool 4; an sub consisting of an external pipe 5, fixed by means of a sleeve 2 on the housing 1 and an internal pipe 6, connected by means of a nipple 7 with a drill pipe string 8, the external pipe 5 having internal slots 9, which interacts with external slots 10 made on the internal pipe 6; centralizer 11; deep groove ball bearing 12; thrust ball bearing 13; a spacer 21 located between the bearings 12 and 13; support ring 22; a cork-shaped radial valve 19, equipped with a double row ball bearing 20 and having vertical channels 25; self-sealing rubber element 27 with a clamping ring 28; a nut 23 with a lock nut 24; a core receiver pipe 14 having at its upper end a conical groove 17 and radial holes 18; core body 29, having a support protrusion 30, on which a radial annular groove 31 is made, and a collet core core 32, an intermediate ring 33 and a lever core core 34 are installed in the body; a support 35 having an end annular groove 36, fixing screws 37, a thrust ball bearing 38, the cavity of which is filled with grease, a bearing pad 39, an oil seal 40 and a pressure ring 41, a chamber 42 filled with a core insulating composition and having a displacer 43 and provided on the upper parts of the cuff 44, and on the lower part has protrusions 45; a tip 46 mounted on the displacer plunger 43.

 The deep groove ball bearing 12 includes an inner race 47, an outer race 48, balls 49, an end race 50 fixed to the inner race 47, O-rings 51 and 52.

 The thrust ball bearing 13 includes an upper race 53, a thrust race 54, balls 55, O-rings 56 and 57, ring 58.

 The spacer 59, on which the protrusions 45 of the chamber 42 are supported; support ring 60, mounted on the outer pipe 5, interacting with the slots 10 of the inner pipe 6 and provided with a seal 61 and a clamping nut 62.

 Channels 63 made on the centralizer 11; an axial channel 64 made on the displacer plunger 43; plug 65 mounted on tip 46.

 Holes 66 on the displacer plunger 43; holes 67 on the chamber 42.

 The intermediate support 68, made on a sliding bearing, centering the core receiving pipe 14 during inclined drilling.

 A retaining screw 69, fixing the ring 15 with ejectors 16 on the core receiving pipe 14; cavity 70 in the core receiving pipe 14; a coupling 71 provided with adjusting rings, having centralizers and fixed in the upper part of the core receiving pipe 14; centralizers 72, made on the core core body 29.

 The coring shell works as follows.

 The core sampling shell before its work undergoes maintenance in a specialized workshop for preparing core sampling shells for work and after that it is delivered to the rig in full completeness.

 A coring shell is lowered into the well in assembled form and is fixed with rotor wedges at the wellhead, and an elevator is installed between the rotor and clutch 2. After that, the outer pipe 5 of the sub is unscrewed from the sleeve 2 and the latter is removed to the side. The core receiver pipe is filled with a liquid, for example, used engine oil, and the outer pipe 5 of the sub is screwed into the sleeve 2 and, according to known technology, the core sample is lowered into the well to the bottom.

 During the launching of the core sampling projectile in the well, the outer pipe 5 is held by a support restrictive ring 60 on the slots 10 of the internal pipe 6. In this position, the internal pipe 6 is moved to the upper position relative to the external pipe 5 and the centralizer 11 is moved together with the internal pipe, the upper part of the core-receiving pipe 14 is a plug-shaped radial valve 19, while the radial valve 19, moved along the core-receiving pipe, closes the radial windows 26 on the latter, which prevents oil from the cavity 70 of the core pipe 14 to the discharge valve 3. At the same time, the cavity 70 of the core pipe 14 further seals the self-sealing rubber element 27 pressed by the ring 28 under liquid pressure. As a result of these technological solutions, when lowering the core sampling shell to the bottom and performing intermediate flushing of the wellbore during this period, the fluid from the core receiver pipe 14 is not expelled and, accordingly, the core insulation composition is not expelled from the chamber 42 and from the plane of the core core body 29.

 When the coring shell reaches the bottom, then due to the weight of the drill pipe string 8 and the nipple 7 together with the inner pipe 6 moves the centralizer 11 to the lower position, and the nipple 7 rests on the nut 62, which limits its further movement, and the cork-shaped radial mounted on the centralizer 11 the valve 19 is moved to the lower position, opening the radial windows 26 on the core receiver pipe 14, while the cavity 70 of the latter through the radial windows 26, through the channels of the ejectors 16 communicates with the discharge channel 3. Upon reaching ernootbornym projectile comprise slaughtering wash liquid circulation and begin drilling.

 The flushing fluid injected from the surface flows from the drill pipe string 8 to the upper part of the centralizer 11, from where it passes through the channels 63 to the injection duct 3, through the flushing holes on the rock cutting tool 4, it goes to the bottom, from there it carries out sludge and comes to the surface through the annulus. As a result of deepening the bottom hole, the core being drilled moves along the axial channel of the rock cutting tool in the cavity of the core core body 29 and in the cavity of the core receiving pipe 14. In this case, the core being drilled interacts with the tip 46, which moves together with the displacer 43 up, while the chamber 42 moves up . When moving the displacing plunger 43 together with the chamber 42, the displacing plunger has less resistance to the resistance of the chamber 42, and ke is extruded from the chamber 42 through the holes 67 noizoliruyuschy composition which rests on the wall 14 of the core tube.

 As a result of the washing fluid passing through the injection channel 3 at a certain speed through the ejectors 16 and vertical channels 25, the liquid is sucked out from the upper part of the cavity 70 of the core receiver pipe 14 and the core together with the chamber 42 moves freely in the core receiver pipe 14, and in the cavity 70 during this period, a certain degree of evacuation is created, which reduces the pressure on the core. In this case, the core being drilled, which is transported in the core receiver pipe 14, is not subjected to the hydraulic pressure of the flushing fluid, while the core is covered with a core insulating composition that covers the walls of the core receiver pipe 14.

 During the drilling period, the core receiving pipe 14 is not subjected to rotational movement, this is facilitated by the thrust ball bearing 38 located on the support 35, and the radial ball bearing 12 mounted on the centralizer 11, and when axial walking of the core receiving tube 14 occurs, its upper end interacts with the thrust bearing 13, and at more than ten meters of the length of the core receiving pipe 14 and for inclined drilling, the core receiving pipe 14 is centered by an intermediate support 68. When the radial windows 26 are open and from the cavity of the core receiving pipe 14 through to Of the channels 25, liquid is aspirated, the pressure ring 28 does not affect the self-sealing rubber element 27, which does not affect the core-receiving pipe 14 and the deep groove ball bearing 12.

 After completion of the drilling program, the drilling fluid is stopped and the flushing fluid is turned off and the core sample is lifted to the surface using a known technology, and at the wellhead, the core sample shell is fixed with rotor wedges, and the elevator is fixed between the coupling 2 and the rotor.

 At the wellhead, a branch pipe 2 is unscrewed from the sleeve by a mechanical wrench 5, the sub assembly and the inner pipe 6 being assembled, the centralizer 11 is turned to the side. After that, the sling provided with a pin through the radial holes 18 is taken out of the housing 1 of the core receiver pipe 14, and the fixing screws 37, by means of an annular groove 31 on the core drill body 29, hold the support 35, which is removed from the housing 1 together with the core receiver pipe 14, which are laid on the surface on scaffolds, for laying. The core-tapper case 29 is unscrewed from the core pipe 14. A pipe (screw known in the art as an inventory device, not shown in the drawing) is screwed onto the core pipe 14, equipped with a rubber stopper and a fitting on which the discharge hose is mounted, include a squeezing fluid and under pressure 2- 3 atm core is extracted from the core receiver pipe 14. The extracted core is cut into meter sections, which are marked, wrapped with gauze, put in a special container, filled with paraffin and sent to a specialized laboratory for research.

 After maintenance, the coring shell is assembled. In the core collection pipe 14, a chamber 42 is assembled with a displacer plunger 43 and a spacer 59, screwed to the core collection pipe 14 in the assembled form, the core drill body 29, the plug 65 is unscrewed on the tip 46 and the core insulation is pumped through the axial channel of the latter, which is pumped through the axial channel 64 fills the chamber 42 and through the openings 67 fills the annular space between the chamber 42 and the core receiver pipe 14, and through the openings 66 fills the existing cavity of the core drill body 29, screw into the axial channel of the tip 46 of the tube at 65.

 If necessary, make the replacement of the ring 15 with the ejectors 16 of the desired section of the channels and the ring 15 on the core receiving pipe 14 is fixed with screws 69.

 Centralizers made on the coupling 71 and centralizers 72 serve as guides during the descent of the core receiving pipe into the housing 1 and when lifting it from the housing.

 The core receiver pipe 14 is assembled lowered into the housing 1 and the cavity of the core receiver pipe 14 is filled with liquid, and the sub is assembled by means of the outer pipe 5 is fixed on the sleeve 2 of the housing 1. After that, the core sample is lowered into the well until the bottom, the process is repeated.

 The constructive solution of the coring shell allows it to be quickly and quickly serviced directly at the rig, which eliminates the traditional need to transport coring shells to specialized workshops for technical maintenance.

 This embodiment of the core sampling shell allows to achieve complete removal of a representative core that is protected from flushing the filtrate with drilling mud, and covered with a core insulating composition, this confirms the test of the prototype core sampling shell of the proposed design at the Novy Urengoy gas field.

Claims (5)

 1. A core sample containing a housing with a sleeve attached to it, a rock cutting tool, an adapter for connecting to a drill pipe string, including an external pipe mounted by means of a sleeve on the body, a centralizer equipped with a deep groove ball bearing, ejectors, a core receiver pipe installed by the lower end through the body core drill on the support, and the upper end mounted on a radial ball bearing, and a chamber equipped with a displacer plunger, filled with a core insulating composition, distinguishing Keep in mind that the sub additionally contains an internal nozzle connected by means of a nipple to the drill pipe string, a centralizer fixed to the internal nozzle and provided with a thrust bearing, a deep groove ball bearing mounted on the centralizer, made of double row with bulk balls in a sealed housing filled with grease, a thrust bearing mounted on a centralizer, made with bulk balls in a sealed housing filled with grease, the core receiver pipe is fixed with its upper end on a radial double-row ball bearing, interacts with its end face with a thrust bearing and is equipped with a ring, ejectors are mounted on the said ring, a plug-shaped radial valve made in the rubber-metal version, equipped with a double-row ball bearing and with the possibility of reciprocating movement along the axis of the core receiving pipe is installed on the lower end of the centralizer , for sealing the cavity of the core-receiving pipe, a self-sealing rubber element with a pressure ring is provided, the housing core-tappers are made conical on the inside, and a radial annular groove is made on its lower supporting protrusion, while the support has an end annular groove and is equipped with locking screws that interact with a radial annular groove made on the lower supporting protrusion of the core-tapping case, and on the lower part a support for the stuffing box is made, which is fixed by a clamping ring, a tip is attached to the lower end of the displacer-plunger, which interacts with the stuffing box and with the drill core and m is razravnivatelem kernoizoliruyuschego composition on the core tube.  2. A coring shell according to claim 1, characterized in that the deep groove ball bearing is made in the form of a block consisting of an inner cage made with an end cage, an outer cage made in the middle with a double-ended end cage, an end cage fixed to the inner cage, and balls were laid between the cages, moreover, annular grooves are made on the end outer cages, in which seals are installed that interact with the outer cage, while the outer casing has annular grooves in which claimed seals cooperating with the core tube.  3. A core sample according to claim 1, characterized in that the thrust ball bearing is made in the form of a block consisting of an upper cage, a thrust cage, and balls are laid between the cages, the cages interacting with each other by means of the seals provided with them, the cages being fixed to each other and between the seals with a ring, while the thrust clip interacts with the end face of the core receiving pipe.  4. The core sample according to claim 1, characterized in that the displacer plunger is made with an axial channel communicating with the chamber cavity, with openings communicating the axial channel with the cavity core body cavity.  5. A core sample according to claim 1, characterized in that the tip has an axial channel, which is equipped with a plug.