CN200943459Y - Device for repairing oil-gas drilling casing - Google Patents

Device for repairing oil-gas drilling casing Download PDF

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Publication number
CN200943459Y
CN200943459Y CN 200620119273 CN200620119273U CN200943459Y CN 200943459 Y CN200943459 Y CN 200943459Y CN 200620119273 CN200620119273 CN 200620119273 CN 200620119273 U CN200620119273 U CN 200620119273U CN 200943459 Y CN200943459 Y CN 200943459Y
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China
Prior art keywords
repairing
pipe
centralizer
cementing
gas drilling
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Expired - Lifetime
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CN 200620119273
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Chinese (zh)
Inventor
姜伟
张春阳
刘良跃
王本奎
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China National Offshore Oil Corp CNOOC
CNOOC Research Institute Co Ltd
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China National Offshore Oil Corp CNOOC
CNOOC Research Center
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Priority to CN 200620119273 priority Critical patent/CN200943459Y/en
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Abstract

The utility model pertains to a device to repair the oil/gas well casing, characterized in that the device includes several casings, the casings are thread-connected to form a complete section of repairing casing string, the repairing casing string is arranged with a cementing nipple at a place corresponding to the rupture in the production casing, the cementing nipple has 3-6 through holes on the wall, the through holes keep a uniform phase difference along the circumferential position, the upper and lower parts of the cementing nipple each has two protruding cement baskets, the repairing casing string under the cement basket at the lower part is arranged with a packing ring on each of the joints between two adjacent casings, the packing ring is arranged with a rigid centralizer on both the upper and lower parts, the lower rigid centralizer is arranged with an elastic centralizer below, and the upper rigid centralizer is arranged with a retaining ring above. The utility model is effective and simple in structure, and can be widely used to repair production casings.

Description

A kind of device of repairing oil/gas drilling bushing
Technical field
The utility model relates to a kind of device of repairing oil/gas drilling production casing.
Background technology
In the development process in marine oil gas field, what adopt at present is simultaneously intensive cluster well group development operation mode.So-called simultaneously intensive cluster well group development operation mode is meant on an offshore boring island, adopts 1.5m * 1.8m well head spacing, 5 mouthfuls of well/row * 7 rows, the big wellhead platform dense cluster group exploitation of 35 mouthfuls of well slots.This operating type can reduce platform quantity, reduces one times of platform workover rig quantity, also is convenient to production management from now on simultaneously, reduces expenses.The characteristics of intensive cluster well group production drilling operation are: concentrate to bore solid 13-3/8 " after the top layer, bore one by one again and open oil reservoir, following production casing.Because the cluster well well spacing is intensive, therefore, normally the subdrilling displacement is big, the Bian Bujing that kickoff point (KOP) is shallow, and it is little to bore displacement then, the middle part well that kickoff point (KOP) is dark, the influence of magnetic disturbance in the time of can reducing directional inclination like this guarantees the security control of well track.But, the cluster well group development operation mode that this while is intensive, very strict to the drillng operation requirement, the quality requirement height, particularly in the drilling well later stage of platform, well anti-collision problem becomes increasingly conspicuous, and has brought new challenge for drilling technology and management.
Because the cluster well well spacing is intensive, in drilling process, the situation that adjacent drilling well production casing is drilled may take place in the angle buildup interval on drilling well top, drill bit when passing the upper dense well pattern.Because well pattern is intensive, existing measurement while drilling instrument is subjected to magnetic disturbance, can not accurately measure the well orientation, thus drill bit to collide worn out adjacent drilling well production casing be a problem that is difficult to avoid.Drilled the drilling well of production casing by drill bit, at intact production casing down (9-5/8 " sleeve pipe), and finished in the well of well cementation, how to handle the production casing of wearing and tearing, this is major issue that urgency is to be solved in the cluster well group.
For this reason, the applicant has proposed a kind of new method (applying for patent of invention simultaneously) of repairing oil/gas drilling production casing, it may further comprise the steps: 1) be lowered to by 7 in production casing from wellhead platform " the repairing pipe string formed of sleeve pipe, the cut place of the corresponding production casing of the cementing pipe nipple on described repairing pipe string; 2) with conventional cementing 5 " the leather cup instrument injects cement paste down to the cementing pipe nipple place of repairing the pipe string; cement paste is behind the space of filling with on the leather cup instrument between two groups of leather cups; return in that the through hole that is provided with from the cementing pipe nipple under the effect of cement pressure is evenly outer; enter in the annular space of repairing between pipe string and the production casing; after well head has cement paste to return out; replace into the cement gel plug, trip-out then, and cement plug and leather cup instrument take out thereupon; 3) closing well is waited and is coagulated, and until theing cement solidifies, production casing is finished by repairing.
Summary of the invention
The purpose of this utility model provides a kind of device that can realize said new method repairing oil/gas drilling production casing.
For achieving the above object, the utility model is taked following technical scheme: a kind of device of repairing oil/gas drilling bushing, it is characterized in that: it comprises some sleeve pipes, the repairing pipe string of described sleeve pipe by being threaded in aggregates, break location with the pre-production casing of repairing on described repairing pipe string is corresponding, be provided with a cementing pipe nipple, the tube wall of described cementing pipe nipple is provided with 3~6 through holes, each described through hole keeps a uniform phase difference along circumferential position, the basket that respectively is provided with the protrusion that two external diameters cooperate with the production casing internal diameter up and down of described cementing pipe nipple.
On the repairing pipe string below the basket of described bottom, continuous two joint sleeve pipe junctions are respectively arranged with a packing cushion rubber, at described packing cushion rubber a rigidity centralizer is set respectively up and down, below the described rigidity centralizer below an elastic centralizer is set, above the superincumbent described rigidity centralizer fixing hoop is set.
Through hole on the described cementing pipe nipple is 4 of 90 degree phase differences settings at interval, and the difference in height between the described through hole is less than 100mm.Through-hole diameter on the described cementing pipe nipple is 20mm.
Each original interconnective tube coupling place at preceding 7 sleeve pipes of described repairing pipe string, set up a rigidity centralizer and an elastic centralizer, between the 7th~25 sleeve pipes, per 2 sleeve pipes are set up an elastic centralizer, one until last root sleeve pipe after the 25th sleeve pipe, and per 3 sleeve pipes are set up an elastic centralizer.
Described repairing pipe string bottommost is provided with a guide shoe with the groove that tilts from inside to outside.
The utility model is owing to take above technical scheme, it has the following advantages: 1, the utility model is owing to be provided with a cementing pipe nipple corresponding with break location on the production casing in repairing the pipe string, and through hole and basket be set on the cementing pipe nipple, therefore when by 5 " when cementing leather cup instrument injects cement in the cementing pipe nipple; can return cement to production casing and the annular space repaired between the pipe string by the through hole on the cementing pipe nipple; and behind C.I.P; the cement of living its top by the basket support on cementing pipe nipple top; prevent that top cement from pressing downwards; from through hole, return again to repair to manage and go here and there, live in by the basket support of cementing pipe nipple bottom simultaneously, near cement in the annular space cut between the following basket, it is retained in the annular space, thereby realizes the repairing of production casing cut.2, the utility model device is because the junction of continuous two sleeve pipes below the cementing pipe nipple is provided with the packing cushion rubber, at the packing cushion rubber rigidity centralizer is set respectively up and down, below the rigidity centralizer below elastic centralizer is set, above the superincumbent rigidity centralizer clip is set, therefore can limit the position of repairing cementing pipe nipple in the pipe string better, the cement that assurance is injected is repaired the effect of cut.3, the utility model device has carried out strengthening setting upright in the junction segmentation of whole repairing pipe string, and in the bottommost sleeve pipe of repairing the pipe string, be provided with the groove that ecto-entad tilts, therefore make production casing form an one preferably, can not cause adverse effect the later flow string etc. of removing with repairing the pipe string through repairing work.The utility model can be widely used in the development process of various big wellhead platform dense cluster groups.
Description of drawings
Fig. 1 is the utility model offshore oil and gas drilled well bore structural representation
Fig. 2 is that the utility model is repaired pipe string structure schematic diagram
Fig. 3 is the cementing tool schematic diagram that uses in the utility model method
The specific embodiment
Below in conjunction with drawings and Examples the utility model is described in detail.
It is that example is illustrated that the utility model is chosen in two mouthfuls of wells that the casing wear accident takes place in drilling process and the completion process.Wherein a bite well is in drilling process, when the top angle buildup interval passes the upper dense well pattern, with completed 9-5/8 " sleeve pipe drills at the 469m place.Another mouthful well carries out 9-5/8 in completion pipe cleaning process " during casing pressure test, find that sleeve pipe has breakage, on inspection, find the 9-5/8 of this well " sleeve pipe has two place's cuts respectively at 323m and 325m place, this situation be in the drilling process drill bit with due to the sleeve pipe worn-off.Its relevant technologies data of two mouthfuls of wells following (as shown in table 1) of casing wear accident take place.
Table 1: breakage of two mouthfuls of accident casings and wellbore conditions
Figure Y20062011927300051
When having an accident, a bite well is behind pipe also, and the completion practice of another mouthful well begins.The utility model method adopts first completion, the method of back subsidy sleeve pipe, promptly still earlier according to 9-5/8 " the normal sand control completion program of sleeve pipe completion; after completion finishes; again the sleeve pipe that drills or gall damage being subsidized and repaired; its mending course is basic identical, is example with No. 1 well in the table 1 below, and implementation process of the present utility model is described.
As shown in Figure 1, the utility model repair apparatus comprises one by some 7 " the repairing pipe string 1 formed through being threaded of sleeve pipe; it is arranged on 9-5/8 " in the production casing 2, the overall length of repairing pipe string 1 is roughly 604m (promptly surpassing about the about 280m of cut), and main cut 3 positions and the cement according to the production casing of waiting to subsidize and repair 2 of this length returns high factor and determines.In order between production casing 2 and repairing pipe string 1, to charge into subsidy cement, corresponding with cut 3 positions of production casing 2 on repairing pipe string 1, one cementing pipe nipple 4 (as shown in Figure 2) is set, the tube wall of cementing pipe nipple 4 is provided with 3~6 through holes 5, each through hole 5 keeps certain phase difference mutually on tube wall, such as: through hole 5 is provided with four altogether, phase difference between each through hole 5 is 90 °, each through hole 5 diameter is about 20mm, difference in height between the through hole 5 is controlled in the 100mm, can evenly return out when returning outward with assurance cement.Cement for the support injection, the upper and lower basket 6 that two protrusions respectively are set at cementing pipe nipple 4, continuous two joints below cementing pipe nipple 4 are repaired the sleeve pipe junction of managing string 1 simultaneously, be respectively arranged with a packing cushion rubber 7, at packing cushion rubber 7 a rigidity centralizer 8 is set respectively up and down, an elastic centralizer 9 is set below the rigidity centralizer 8 below, and it is fixing that a clip 10 is set above the superincumbent rigidity centralizer 8.In addition, in order to make repairing pipe string 1 in production casing 2, keep setting upright state, begin to count from well head, each original interconnective tube coupling place at preceding 7 sleeve pipes of repairing pipe string 1, set up a rigidity centralizer and an elastic centralizer, between the 7th~25 sleeve pipes, per 2 sleeve pipes are set up an elastic centralizer, one until the minor details of repairing to 604 meters of well depth that pipe goes here and there after the 25th sleeve pipe, and per 3 sleeve pipes are set up an elastic centralizer.Above-mentioned packing cushion rubber 7, rigidity centralizer 8, elastic centralizer 9 etc. are oil field accessories commonly used.Between repairing pipe string 1 bottommost and production casing 2, a guide shoe 11 (guide shoe is a prior art) is set, groove on the guide shoe 11 is at 9-5/8 " production casing 2 and the reducing place of repairing between the pipe string 1 form a guide section, and remove flow string and can not impact later.
When adopting the utility model to realize the method for repairing and mending of the applicant's proposition, comprise following implementation process (repairing with No. 1 well in the table 1 is an example):
1, repairs preceding preparation
(1) do shutoff face in production casing 2: the position of 1808m is envelope portion face place, oil reservoirs top in production casing 2; be lowered to the back-off sub of prior art and blanking plug 13 thereof (blanking plug+location sealer 6-2/8 " OD (Outer Diameter external diameter)); block the top of the sand proof well section of completion; form obstruction face; the passage between closed upper portion pit shaft and the lower part borehole;, throw and pour 5 bags of sands protection obstruction faces again into after stifled for guaranteeing not leave over other foreign material in next step well in operation.
(2) reservoir plugging well section: the position of 604m is lowered to the recoverable packer in production casing 2, pressure testing 20MPa * 10min is qualified between recyclable packer and shutoff face, when guaranteeing next step operation, recyclable packer forms the good shutoff to oil reservoir well section, not polluted reservoir.
(3) trip out recyclable packer, replace into thickened drilling fluid 15m by slush pump at former position to the production casing between the obstruction face 2 of putting into recyclable packer 3, about the about 400m of the height of thickened drilling fluid in production casing 2, forming a cement plug, main consideration is for safety, holds the fragment of some well cementation and drilling out.
(4) at offshore boring island well head 13-3/8 " the following 1m of sleeve pipe 14 heads place, cut off 9-5/8 with hydraulic cutter " production casing 2, and so that vacate 13-3/8 " position of sleeve pipe 14 head slips, be prepared for after having descended to repair pipe string 1, blocking and repair pipe string 1 top.
(5) for the annular space between assurance repairing pipe string 1 and the production casing 2 has good cement sealing, before string 1 is managed in repairing down, fully clean production casing 2 inwalls,, guarantee repairing quality with the oil film on the thorough removing tube wall with hot water.
2, will repair pipe string 1 is lowered in the production casing 2, arrive 604m place in the production casing (promptly surpass about cut 3 about 280m and locate) until repairing pipe string 1 bottom, to repair cut 3 places of the cementing pipe nipple 4 corresponding production casings 2 in the pipe string 1, will repair pipe simultaneously and go here and there 1 top card and hang over 13-3/8 " on the slips on the casing head.Be provided with a series of rigidity centralizers 8 and elastic centralizer 9 owing to repair pipe string 1, in production casing 2, set upright placed in the middle so can guarantee to repair pipe string 1.
3, with routine use 5 " cementing leather cup instrument is drilled into for 12 times and returns cement through hole 5 places on the cementing pipe nipple 4 of repairing pipe string 1; according to the program of conventional cementing construction operation; use 5 " leather cup instrument 12 (as shown in Figure 3) injects cement paste, cement paste is from 15 outflows of portalling of leather cup instrument 12, fill with on the leather cup instrument 12, down behind the repairing pipe string 1 between two leather cups 16, can be under the pressure effect that cement injects, return outside evenly each through hole 5 from the cementing pipe nipple 4 of casing repairing string 1, enter in the annular space of repairing between pipe string 1 and the production casing 2, owing to be provided with two baskets 6 below the cementing pipe nipple, and also be provided with two packing cushion rubbers 7 in the bottom of cementing pipe nipple 4, therefore the cement of clamp-oning annular space can not walked downwards, but the gap between top basket 6 and production casing 2 is up, along with being full of whole annular space gradually, cement paste have cement paste to return out until well head, cement is full of in the proof annular space, replace into the cement gel plug, pull out of hole then, cement plug and leather cup instrument take out thereupon.For guaranteeing that in the cementing process, the reason cement slurry density is not too high, leak and the stratum, cut 3 place of production casing 2 squeezed, strict control cementing annular space equivalent pressure in 1800psi (1psi=0.0067MPa).
4, closing well is waited and is coagulated: after injecting cement, cement is gone here and there and is poured in down a chimney in 1 to repairing pipe in the annular space that causes for the pressure reduction imbalance that prevents to repair cement pressure and the cement pressure in the annular space in the pipe string 1, carry out closing well and wait with fixed attention, closing well is waited and is belonged to routine operation with fixed attention, is not described in detail.Closing well between the waiting-on-cement the upper and lower basket 6 of cementing pipe nipple 4 can play the effect of its top cement of support, keep therebetween all the time to guarantee the cement in the annular space, thereby make the cement in the annular space with the cut on the sleeve pipe 23 good sealing effect be arranged producing.
5, remove residual cement: the drilling assembly of employing is 6 " drill bit+4-3/4 " dredge pump motor+3-1/2 " drilling rod, because of using the workover rig operation, TORQ power is limited, therefore is equipped with 3 #The operation of cement pump motor.When boring the residual cement of repairing thoroughly in the pipe string 1, the saturating pipe string 1 interior cement of repairing of brill is drilled into 644m down and confirms that mending course finishes till the cement-free to 608m.
In the foregoing description; repairing the length of pipe string 1, the height of some positions and size, phase difference and the difference in height etc. in aperture all is the 9-5/8 that repairs according to pre-" cut 3 positions on the production casing 2 and cement returns high factor decision; and need to design and operate according to actual conditions in practical operation, the conversion of these sizes should not influence protection domain of the present utility model.

Claims (10)

1, a kind of device of repairing oil/gas drilling bushing, it is characterized in that: it comprises some sleeve pipes, the repairing pipe string of described sleeve pipe by being threaded in aggregates, break location with the pre-production casing of repairing on described repairing pipe string is corresponding, be provided with a cementing pipe nipple, the tube wall of described cementing pipe nipple is provided with 3~6 through holes, each described through hole keeps a uniform phase difference along circumferential position, the basket that respectively is provided with the protrusion that two external diameters cooperate with the production casing internal diameter up and down of described cementing pipe nipple.
2, the device of a kind of repairing oil/gas drilling bushing as claimed in claim 1, it is characterized in that: on the repairing pipe string below the basket of described bottom, continuous two joint sleeve pipe junctions are respectively arranged with a packing cushion rubber, at described packing cushion rubber a rigidity centralizer is set respectively up and down, below the described rigidity centralizer below an elastic centralizer is set, above the superincumbent described rigidity centralizer fixing hoop is set.
3, the device of a kind of repairing oil/gas drilling bushing as claimed in claim 1 is characterized in that: the through hole on the described cementing pipe nipple is 4 of interval 90 degree phase differences settings, and the difference in height between the described through hole is less than 100mm.
4, the device of a kind of repairing oil/gas drilling bushing as claimed in claim 2 is characterized in that: the through hole on the described cementing pipe nipple is 4 of interval 90 degree phase differences settings, and the difference in height between the described through hole is less than 100mm.
5, as the device of claim 1 or 2 or 3 or 4 described a kind of repairing oil/gas drilling bushings, it is characterized in that: the through-hole diameter on the described cementing pipe nipple is 20mm.
6, as the device of claim 1 or 2 or 3 or 4 described a kind of repairing oil/gas drilling bushings, it is characterized in that: at each original interconnective tube coupling place of preceding 7 sleeve pipes of described repairing pipe string, set up a rigidity centralizer and an elastic centralizer, between the 7th~25 sleeve pipes, per 2 sleeve pipes are set up an elastic centralizer, one until last root sleeve pipe after the 25th sleeve pipe, and per 3 sleeve pipes are set up an elastic centralizer.
7, the device of a kind of repairing oil/gas drilling bushing as claimed in claim 5, it is characterized in that: at each original interconnective tube coupling place of preceding 7 sleeve pipes of described repairing pipe string, set up a rigidity centralizer and an elastic centralizer, between the 7th~25 sleeve pipes, per 2 sleeve pipes are set up an elastic centralizer, one until last root sleeve pipe after the 25th sleeve pipe, and per 3 sleeve pipes are set up an elastic centralizer.
8, as the device of claim 1 or 2 or 3 or 4 or 7 described a kind of repairing oil/gas drilling bushings, it is characterized in that: described repairing pipe string bottommost is provided with a guide shoe with the groove that tilts from inside to outside.
9, the device of a kind of repairing oil/gas drilling bushing as claimed in claim 5 is characterized in that: described repairing pipe string bottommost is provided with a guide shoe with the groove that tilts from inside to outside.
10, the device of a kind of repairing oil/gas drilling bushing as claimed in claim 6 is characterized in that: described repairing pipe string bottommost is provided with a guide shoe with the groove that tilts from inside to outside.
CN 200620119273 2006-08-10 2006-08-10 Device for repairing oil-gas drilling casing Expired - Lifetime CN200943459Y (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106639946A (en) * 2016-12-27 2017-05-10 神华集团有限责任公司 Mine sleeve repairing method
CN106761531A (en) * 2016-12-19 2017-05-31 长江大学 A kind of plugging while drilling instrument

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106761531A (en) * 2016-12-19 2017-05-31 长江大学 A kind of plugging while drilling instrument
CN106761531B (en) * 2016-12-19 2019-08-23 长江大学 A kind of plugging while drilling tool
CN106639946A (en) * 2016-12-27 2017-05-10 神华集团有限责任公司 Mine sleeve repairing method
CN106639946B (en) * 2016-12-27 2019-05-03 神华集团有限责任公司 Mining casing salvaging method

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CP01 Change in the name or title of a patent holder

Address after: 100027 Beijing city Dongcheng District Dongzhimen Street No. 6

Patentee after: China National Offshore Oil Corporation

Patentee after: CNOOC Research Institute

Address before: 100027 Beijing city Dongcheng District Dongzhimen Street No. 6

Patentee before: China National Offshore Oil Corporation

Patentee before: CNOOC Research Center

CX01 Expiry of patent term

Granted publication date: 20070905

EXPY Termination of patent right or utility model