CN101824973A

CN101824973A - Oil-swelling self-packing packer

Info

Publication number: CN101824973A
Application number: CN200910008104A
Authority: CN
Inventors: 王跃胜; 张玉明
Original assignee: HEBEI BAOSHI SPECIAL FLEXIBLE RUBBER CHEMICAL INDUSTRY Co Ltd
Current assignee: HEBEI BAOSHI SPECIAL FLEXIBLE RUBBER CHEMICAL INDUSTRY Co Ltd
Priority date: 2009-03-02
Filing date: 2009-03-02
Publication date: 2010-09-08

Abstract

The invention relates to fracture, cementation, completion and water/oil layer packing in oil wells, in particular to an oil-swelling self-packing packer 10 comprising a rubber tube 4 made of 'expandable elastic' rubber materials, wherein the rubber tube 4 is capable of absorbing hydrocarbons and swelling when the rubber tube 4 is arranged in the hydrocarbons; and the rubber tube is fixed on an oil production pipe 7 via a metal retaining ring 3 and connected with other oil production pipes via a casing collar 1. The rubber tube 4 is capable of swelling by contacting and absorbing the hydrocarbons, a ring-shaped space 6 can be formed between the closed well wall 5 of the packer 10 and the oil production pipe 7, thus achieving the purpose of packing.

Description

Oil-swelling self-packing packer

Technical field

The present invention relates to the packing of pressure break, well cementation, completion and the water layer oil reservoir of oil well.The oil-swelling self-packing packer that relates to has adopted a kind of special " expandandable elastomeric " material." expandandable elastomeric " material is a kind of elastic rubber material that will expand when placing in the particular fluid [(swelling) expands in oil].Also relate to the down-hole self-packing packer of using this expandandable elastomeric material, this packer is made of expandandable elastomeric material and mechanical tubing string, metal baffle ring etc.

Technical background

Packer is the important tool of oil-separating layer, is used for the seperated layer water injection of pressure break oil producing operation, oil production by layer, the well cementation of open hole well, completion etc.The completion method of external packer of pipe can be divided three kinds of forms, is respectively external casing packer and slotted liner completion, external casing packer and sliding sleeve completion and external casing packer and bushing pipe perforation completion.

Packer is to rely on the outer packing of pipe to implement the separation of interval as a kind of main layering instrument in down-hole, and it can carry out operation and manufacture control by interval, has important effect in the separate zone production of oil gas well.

Traditional packer has eight kinds of series and a plurality of kinds such as brace type, slip-type, leather cup formula, hydraulic expansion formula, waterpower compression, hydraulic seal formula, suspension type.What wherein the oil field was the most frequently used is expanding and two kinds of packers of compression.Conventional packer all is that dependence external force, the structure of operating machine are carried out packer setting.The type packer is prone to phenomenons such as sand card, premature setting when going into the well, the risk height, and reliability is relatively poor.

In this field, mainly contain four companies Related product and technological service are provided: Halliburton Company, Shell Co. Ltd, TAM company and BakerHughes company.Schlumberger company and Vad good fortune company are also developing similar products.Also there are not similar products to occur but China is domestic.

Britain BP and U.S. ConocoPhilips company once used the technology that the expansion type instrument carries out the packing operation in exploitation U.S. Alaska north slope shallow-layer heavy oil belt, obtain good economic benefits (SPE97928).

U.S.'s Alaska north slope is containing hundred million barrels of heavy oil resources of 200-250, mainly is distributed in the stratum of underground 3000-5000 foot.Alaska is located in the Arctic Circle, and ground environment is very abominable, low-temperature cold all the year round, and the heavy oil belt location is a permafrost by 1800 feet of below grounds.Target zone is had tomography simultaneously again by numerous unstable rammells and water outlet sand layers double team.In the face of huge challenge, how oily company pays special attention to cost-effective exploitation heavy oil resource.

Two companies have just considered Halliburton's technology in the oil field development starting stage.Oil field development is adopted 3 branches or 4 branch horizontal wells to bore completion technique and is exploited a plurality of heavy oil intervals simultaneously.Target zone then is connected blind pipe with the oily inflatable packer of chance and is isolated with the sand control screen completion of pre-manufactured hole, unstable rammell, water outlet sand layers and tomography.Development plan has been abandoned the cementing operation, all adopts the completion tubular string directly to be lowered to the mode of bore hole, has reduced risk and operating cost, has protected reservoir simultaneously effectively.

In order to guarantee accurately to isolate bad ground (shale and water layer), the LWD technology has been adopted in drilling well.Before the completion, also to be lowered to caliper and logging equipment, the situations such as position of the hole diameter of target zone well, oil-water interfaces, complicated interval are accomplished fully to understand and grasp.According to actual conditions, select the packing instrument of various outer diameter to form the completion tubular string.

After the operation, well yield reaches 5000 barrel per days, exceeds several times than 200 barrel per days of early development oil well.Production period does not take place that the output that causes because of expansion type packing tool failures descends and the problem of moisture content rising yet.

Britain and American Oil Co. show in the successful experience of Alaska operation, expansion type packing instrument replaces existing downhole packing technology and is used for completion, can significantly reduce the generation of down-hole accident, reduce operating risk and cost, the complicated workover treatment in back of avoiding going into operation.

The content of invention

The objective of the invention is to pluses and minuses with reference to domestic and international original downhole packer product, solving conventional packer relies on external force, occurs phenomenons such as sand card, premature setting when the structure of operating machine is carried out packer setting easily when going into the well, the risk height, the problem that reliability is relatively poor.Invent a kind of reliability height, easy and simple to handle, eliminated well workover and underground work, reduction maintenance cost, prolonged the oil well life-span, be applicable to that downhole temperature and pressure change, improve the novel packing product of cementing quality.

The packer that packing element that the present invention mainly is made of a kind of " expandandable elastomeric " elastic rubber material that will expand when placing in the particular fluid [expanding (swelling) in oil] and mechanical tubing string, metal baffle ring etc. are formed.Be used to seal the annular space between the Petroleum Production well borehole wall and the production tube.Wherein mechanical tubing string is connected with production tube, and the metal baffle ring plays effect fixing and that proofread and correct packer.After packing element that attached oily expanding expandandable elastomeric material outside the mechanical tubing string constitutes arrives the appointed area, thereby the hydrocarbon multiple that can absorb within a certain period of time wherein when touching oil or oil water mixture expands, and reaches the effect of automatic packing.

The packing element that " expandandable elastomeric " elastic rubber material that will expand when placing in the particular fluid [expanding (swelling) in the oil] constitutes has at least following several on material: ZBR rubber, acrylonitrile-butadiene rubber, neoprene, rubber mass rubber, carbon black, zinc oxide, stearic acid, attached old agent, stabilizing agent, inorganic filler, the attached material of high oil suction etc.

The attached material of high oil suction described in this material will absorb and expands thereby touch hydrocarbon in adding rubber to and after special process processing.

Description of drawings

Fig. 1: product basic block diagram;

Fig. 2: the longitdinal cross-section diagram that the present invention works in producing well.

The specific embodiment

Oil-swelling self-packing packer 10 is used for the Petroleum Production well, be fixed on and produce with on oil pipe 7 outer walls, the packing element 4 of packer touches and can absorb hydrocarbon wherein behind oil in the oil well or the oil water mixture and expand, along with constantly swelling of packing element 4, thereby with annular space 6 sealings that form between the borehole wall 5 and the production tube 7.This packer 10 is mainly used in the seperated layer water injection in the pressure break oil producing operation, oil production by layer, and the well cementation of open hole well, completion etc. replace the common tube external packer, and the Petroleum Production well is carried out the segmentation packing, thereby reach the purpose of oil production by layer, raising output.

Packing element 4 is placed on production tube (mechanical tubing string) 7 outsides, and is fixing by metal baffle ring 3, makes it can not break away from; This section production tube 7 is connected with other oil pipe through casing coupling 1 and enters producing well; Packing element 4 can be controlled through prescription adjustment and absorb the speed that expands behind the hydrocarbon, avoids expanding in the process of going into the well, and makes packer 10 not arrive the precalculated position, does not have the packing purpose; Packer 10 is after arriving the precalculated position, oil stream (the well liquid that oil or oil water mixture constitute) 11 in the production well can flow through packer 10, make packing element 4 touch hydrocarbon, thereby making packer 10 absorb hydrocarbon expands, the annular space 6 that forms between the sealing borehole wall 5 and the production tube 7, stop up oil stream flow direction, make oily stream enter production tube 7 by attached sand filter 8.

Packer 10 comprises packing element 4, " expandandable elastomeric " elastic rubber material that this packing element 4 will expand when placing in the particular fluid constitutes, and this material comprises following several at least: ZBR rubber, acrylonitrile-butadiene rubber, neoprene, rubber mass rubber, carbon black, zinc oxide, stearic acid, attached old agent, stabilizing agent, inorganic filler, the attached material of high oil suction etc.Through various attached material proportionings and processing, make it to reach certain intensity, thereby after expansion, can bear down-hole pressure, reach the sealing purpose.

The predominant use of oil-swelling self-packing packer comprises:

1, oil well completion: horizontal well/extended reach well interlayer packing is to implement the segmentation exploitation;

2, the reservoir segmentation is transformed: fixed tubular column is directly gone into operation after transforming;

3, packing water layer: can implement in advance and the later stage water-blocking operation, its expanded granular can be used as efficient sealing agent and profile control agent;

4, improve cementing quality: can guarantee that cased well cement sheath after going into operation still has good sealing performance;

5, can be used for gravel pack completion and expansion tube completion: further improve sealing.

With compare with the packing technology under the existing well, the present invention possesses following advantage:

1, reliability height: do not have mechanical moving element, field operation need not the expert and instructs.

2, auto-compensation annular clearance: the hot power space that sustainable expansion causes to remedy the production fluid erosion surface of expanding. Caused leakage when this type of fault takes place, even under lower pressure reduction, dynamic swelling still can finally realize sealing, and this characteristic makes it to be well suited for using in barefoot interval, and this is that this technology is with respect to the great advantage of other packer technology.

3, can be setting under the static temperature condition of down-hole: the variation of downhole temperature can not cause the stressed variation of packing element volume and tubing string.

4, structure forms flexibly: this packer latus rectum is big, possesses suitable intensity, can pass through long net horizontal section and casing sidetracking section under the prerequisite that guarantees effectively work. When intelligent well completion equipment is installed, can passes smoothly the control pipeline, and need not to be lowered to transition pipe nipple.

5, eliminate well workover and underground work, reduced maintenance cost, prolonged the oil well life-span.

Claims

1. packer 10 by " expandandable elastomeric " material.

This packer 10 by the packing element 4 of oily expanding expandandable elastomeric material, place the production tube 7 of packing element 4 and fixedly the metal baffle ring 3 of packing element 4 constitute.

2. packing element 4 is characterized in that, places hydrocarbon to expand because of absorbing hydrocarbon.

3. as described in requiring as right 1, it is characterized in that packing element 4 is fixed on the production tube 7 by golden institute baffle ring 3.

4. as described in requiring as right 1, it is characterized in that the oily expanding expandandable elastomeric material that packing element 4 is constituted comprises following a kind of at least: ZBR rubber, acrylonitrile-butadiene rubber, neoprene, rubber mass rubber.

5. one kind can be sealed the borehole wall 5 of hydrocarbon production well and the packer 10 of the annular space 6 of production tube 7 formation.Constitute the packing element 4 of this packer 10, this packing element 4 can absorb hydrocarbon, and the speed of expansion after absorbing is controlled.