CN103362456B - Leakage-proof high-seal tooth-width-changing wedge type coupling structure and oil well pipe structure - Google Patents

Abstract

The invention discloses a leakage-proof high-seal tooth-width-changing wedge type coupling structure and oil well pipe structure used in petroleum steel pipe industries. On the longitudinal section of a coupling body, an inner tooth crest outer arc located at the most inner end is connected with an inner transitional cambered face, the inner transitional cambered face is in transition with an inner auxiliary conical face, the inner auxiliary conical face is in transition with an inner auxiliary sealing cambered face, the inner auxiliary sealing cambered face is in transition with an inner main sealing transitional cambered face, the inner main sealing transitional cambered face is in transition with an inner main conical face, the inner main conical face is in transition with an inner main sealing cambered face, the inner main sealing cambered face is in transition with an inner vertex arc, the inner vertex arc is in transition with an inner circular bead arc, the inner circular bead arc is connected with the inner hole wall face of a coupling circular bead through a circular bead. The structure that double cambered faces and the radial diameters of the gourd-shaped main sealing face and the gourd-shaped auxiliary sealing face of the two cambered faces are sealed and the cambered face anti-torque circular bead structure are added to the end portion of the coupling structure. Wedge type threads, the double cambered sealing faces and the anti-torque circular bead are matched, and therefore the sealing performance, the anti-bending capacity, the compressive load resistant capacity and the high anti-torque performance of threaded connector connection are obviously improved.

Description

A kind of anti-leak high sealability becomes tooth wide wedge type box cupling structure and oil well pipe structure

Technical field

The invention discloses the anti-leak high sealability change tooth wide wedge type box cupling structure that a kind of oil drilling industry uses, the invention also discloses the anti-leak high sealability change tooth wide wedged-shaped oil film well casing structure that a kind of oil drilling industry uses.

Background technology

At present, oil casing threaded connection structure form in oil well pipe industry is substantially all to carry out improvement and bring new ideas according to API SPEC 5B " processing of sleeve pipe, oil pipe and line pipe thread, measurement and inspection specification " standard, the quality that is threaded that overall quality of connection compares API standard-required progressively improves a lot, but or can not meet oilfield exploitation instructions for use.The each oil field, the world that causes gradually all connects higher, the more preferably requirement of proposition at double thread, particularly requires more and more stricter to the relevant main performance index of oil well pipe.

Summary of the invention

An object of the present invention overcomes the deficiencies in the prior art, provides a kind of and can increase sealing performance that nipple connects, anti-leak high sealability that bending resistance, incompressible load-carrying ability and high resistance torsional performance all increase becomes tooth wide wedge type box cupling structure.

Another object of the present invention is to provide the anti-leak high sealability that a kind of and above-mentioned box cupling respective outer side edges uses and becomes tooth wide wedged-shaped oil film well casing structure.

According to technical scheme provided by the invention, described a kind of anti-leak high sealability becomes tooth wide wedge type box cupling structure, and comprise box cupling body, the two ends inwall of box cupling body is coupling inner thread section, is provided with box cupling shoulder between two sections of coupling inner thread sections, on direction by the portion wherein, both ends of box cupling body, the facewidth of described coupling inner thread section is in increasing setting gradually, the space width of coupling inner thread section is in reducing setting gradually, the difference of adjacent two facewidth is equal with adjacent two space widths, the height of each tooth of coupling inner thread section is equal, and the tapering of coupling inner thread section is 1:16 ~ 1:24, on the longitudinal cross-section of box cupling body, each tooth in coupling inner thread section is wedge shape, is equipped with barb in the both sides, top of each tooth, the middle top of each tooth in coupling inner thread section is interior crest top land, the inner side of interior crest top land is provided with interior tooth top inner plane, the outside of interior crest top land is provided with interior tooth top outerplanar, interior tooth top inner plane is connected by transition arc in interior crest top land with between interior crest top land, interior tooth top outerplanar is connected by the outer transition arc of interior crest top land with between interior crest top land, it is internal tooth bottom surface in the middle part of teeth groove, internal tooth bottom surface is taper seat, interior crest top land is taper seat, and internal tooth bottom surface, the tapering of interior crest top land is equal with the tapering of coupling inner thread section, the inner side of internal tooth bottom surface is provided with inner plane at the bottom of internal tooth, the outside of internal tooth bottom surface is provided with outerplanar at the bottom of internal tooth, the lateral wall of each tooth is provided with interior spigot surface, the axis angulation of interior spigot surface and box cupling body is 79 ~ 85 °, the inside wall of each tooth is provided with interior bearing surface, the axis angulation of interior bearing surface and box cupling body is 76 ~ 82 °, be connected by transition arc in internal tooth bottom surface between internal tooth bottom surface with inner plane at the bottom of internal tooth, be connected by transition arc outside internal tooth bottom surface between internal tooth bottom surface with outerplanar at the bottom of internal tooth, outerplanar at the bottom of internal tooth is connected by external arc at the bottom of internal tooth with between interior spigot surface, be connected by interior tooth top Inner arc between interior spigot surface with interior tooth top inner plane, inner plane at the bottom of internal tooth is connected by Inner arc at the bottom of internal tooth with between interior bearing surface, be connected by interior tooth top external arc between interior bearing surface with interior tooth top outerplanar, the axis angulation of inner plane at the bottom of internal tooth and box cupling body is 10 ~ 20 °, the axis angulation of interior tooth top outerplanar and box cupling body is 10 ~ 20 °, the axis angulation of outerplanar at the bottom of internal tooth and box cupling body is 7 ~ 17 °, the axis angulation of interior tooth top inner plane and box cupling body is 7 ~ 17 °, and on the longitudinal cross-section of box cupling body, the tooth top external arc being positioned at inner terminal position connects with transition cambered surface, interior transition cambered surface and interior secondary conical surface rounding off, the interior secondary conical surface and interior pair seal cambered surface rounding off, interior pair sealing cambered surface and interior primary seal transition cambered surface rounding off, interior primary seal transition cambered surface and interior main cone face rounding off, interior main cone face and interior primary seal cambered surface rounding off, interior primary seal cambered surface and inner vertex arc smooth transition, inner vertex circular arc and interior shoulder arc smooth transition, be connected by fillet between interior shoulder circular arc and the endoporus wall of box cupling shoulder.

As preferably, the tapering of described coupling inner thread section is 1:18 ~ 1:20.

As preferably, the number of threads of described coupling inner thread section is 12 ~ 30; The first buckle teeth well width of coupling inner thread section is 1.8 ~ 3.2mm; The spigot surface pitch of coupling inner thread section is 3.96 ~ 9.60mm; The bearing surface pitch of coupling inner thread section equals: (internal thread total length deducts 2 times of first buckle teeth groove widths)/(total button number deducts 1); The first buckle teeth of coupling inner thread section is wide is: the spigot surface pitch of coupling inner thread section deducts the first buckle teeth groove width of coupling inner thread section; The tooth depth of coupling inner thread section is 1.5 ~ 2.5mm.

As preferably, on the longitudinal cross-section of box cupling body, the first buckle teeth of coupling inner thread section is wide is 1.8 ~ 3.2mm; The tooth depth of each tooth of coupling inner thread section is 1.5 ~ 2.5mm; The width of interior tooth top inner plane is 0.5 ~ 3.0 mm; The width of interior bearing surface is 0.5 ~ 2.0 mm; Outerplanar width at the bottom of internal tooth is 0.5 ~ 3.0 mm; The outerplanar width of interior tooth top is 0.5 ~ 3.0 mm; The width of interior spigot surface is 0.5 ~ 2.0 mm; The width of inner plane at the bottom of internal tooth is 0.5 ~ 3.0 mm; The width of interior crest top land is 0.05 ~ 6.0 mm; The width of internal tooth bottom surface is 0.05 ~ 6.0 mm; The radius of interior tooth top external arc is 0.20 ~ 0.50mm; The radius of external arc at the bottom of internal tooth is 0.20 ~ 0.50mm; The radius of interior tooth top Inner arc is 0.20 ~ 0.50mm; The radius of Inner arc at the bottom of internal tooth is 0.20 ~ 0.50mm; Outside internal tooth bottom surface, the radius of transition arc is 0.15 ~ 0.30mm; In internal tooth bottom surface, the radius of transition arc is 0.15 ~ 0.30mm; In interior crest top land, the radius of transition arc is 0.15 ~ 0.30mm; In interior crest top land, the radius of transition arc is 0.15 ~ 0.30mm; Angle between the axis that angle between the axis of interior bearing surface and box cupling body is less than interior spigot surface and box cupling body is 2 ~ 6 °.

As preferably, on the longitudinal cross-section of box cupling body, the radius of interior transition cambered surface is 12 ~ 20mm, and the central angle number of degrees corresponding to interior transition arcs face are 10 ~ 15 °; The length of the interior secondary conical surface is 1.0 ~ 3.0mm, and its tapering is 1:14 ~ 1:16; The radius of interior pair sealing cambered surface is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees that interior pair seals cambered surface corresponding are 5 ~ 10 °; The radius of interior primary seal transition cambered surface is 0.0 ~ 2.0mm, and the central angle number of degrees corresponding to interior primary seal transition arcs face are 165 ~ 175 °; The length in interior main cone face is 1.0 ~ 3.0mm, and its tapering is 1:14 ~ 1:16; The radius of interior primary seal cambered surface is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees corresponding to interior primary seal cambered surface are 6 ~ 15 °; The radius of inner vertex circular arc is 0.1 ~ 1.0mm, and the central angle number of degrees that inner vertex circular arc is corresponding are 45 ~ 60 °; The radius of interior shoulder circular arc is 5.0 ~ 15.0mm, and the central angle number of degrees that interior shoulder circular arc is corresponding are 95 ~ 105 °.

A kind of anti-leak high sealability becomes tooth wide wedged-shaped oil film well casing structure, comprise oil well pipe body, the two ends outer wall of oil well pipe body is oil well pipe external thread section, oil well pipe shoulder is provided with between two sections of oil well pipe external thread sections, on direction by the portion wherein, both ends of oil well pipe body, the facewidth of described oil well pipe external thread section is in reducing setting gradually, the space width of oil well pipe external thread section is in increasing setting gradually, the difference of adjacent two facewidth is equal with adjacent two space widths, the height of each tooth of oil well pipe external thread section is equal, the tapering of oil well pipe external thread section is 1:16 ~ 1:24, on the longitudinal cross-section of oil well pipe body, each tooth on oil well pipe external thread section is wedge shape, is equipped with barb in the both sides, top of each tooth, the middle top of each tooth on oil well pipe external thread section is outer crest top land, the inner side of outer crest top land is provided with outer tooth top inner plane, the outside of outer crest top land is provided with outer tooth top outerplanar, outer tooth top inner plane is connected by transition arc in outer crest top land with between outer crest top land, outer tooth top outerplanar is connected by the outer transition arc of outer crest top land with between outer crest top land, it is external tooth bottom surface in the middle part of teeth groove, external tooth bottom surface is taper seat, outer crest top land is taper seat, and outer crest top land, the tapering of external tooth bottom surface is equal with the tapering of oil well pipe external thread section, the inner side of external tooth bottom surface is provided with inner plane at the bottom of external tooth, the outside of external tooth bottom surface is provided with outerplanar at the bottom of external tooth, the lateral wall of each tooth is provided with outer spigot surface, the axis angulation of outer spigot surface and oil well pipe body is 79 ~ 85 °, the inside wall of each tooth is provided with outer bearing surface, the axis angulation of outer bearing surface and oil well pipe body is 76 ~ 82 °, be connected by transition arc in external tooth bottom surface between external tooth bottom surface with inner plane at the bottom of external tooth, be connected by transition arc outside external tooth bottom surface between external tooth bottom surface with outerplanar at the bottom of external tooth, outerplanar at the bottom of external tooth is connected by external arc at the bottom of external tooth with between outer bearing surface, be connected by the left inside circular arc of outer tooth top between outer bearing surface with outer tooth top inner plane, inner plane at the bottom of external tooth is connected by Inner arc at the bottom of external tooth with between outer spigot surface, be connected by outer tooth top external arc between outer spigot surface with outer tooth top outerplanar, the axis angulation of inner plane at the bottom of internal tooth and box cupling body is 10 ~ 20 °, the axis angulation of outer tooth top outerplanar and oil well pipe body is 10 ~ 20 °, the axis angulation of outerplanar at the bottom of external tooth and oil well pipe body is 7 ~ 17 °, the axis angulation of outer tooth top inner plane and oil well pipe body is 7 ~ 17 °, and on the longitudinal cross-section of oil well pipe body, be positioned at external arc at the bottom of the external tooth of outermost end and outer transition cambered surface rounding off, outer transition cambered surface and outer secondary conical surface rounding off, the outer secondary conical surface and outer pair seal cambered surface rounding off, outer pair sealing cambered surface and outer primary seal transition cambered surface rounding off, outer primary seal transition cambered surface and outer main cone face rounding off, outer main cone face and outer primary seal cambered surface rounding off, outer primary seal cambered surface and outer dead centre arc smooth transition, outer dead centre circular arc and outer shoulder arc smooth transition, outer shoulder circular arc and inwall bore hole flat face, inwall bore hole plane connects with transition face, transition face connects with the endoporus wall of oil well pipe external thread section.

As preferably, the tapering of described oil well pipe external thread section is 1:18 ~ 1:20.

As preferably, the number of threads of described oil well pipe external thread section is 12 ~ 30; The first buckle teeth of oil well pipe external thread section is wide is 1.8 ~ 3.2mm; The spigot surface pitch of oil well pipe external thread section is 3.96 ~ 9.60mm; The bearing surface pitch of oil well pipe external thread section is: (it is wide that external screw thread total length deducts 2 times of first buckle teeth)/(total button number deducts 1); The first buckle teeth groove width of oil well pipe external thread section is: it is wide that outer spigot surface pitch deducts first buckle teeth; The tooth depth of oil well pipe external thread section is 1.5 ~ 2.5mm.

As preferably, on the longitudinal cross-section of oil well pipe body, the first buckle teeth of oil well pipe external thread section is wide is 1.8 ~ 3.2mm; The tooth depth of each tooth of oil well pipe external thread section is 1.5 ~ 2.5mm; The width of outer tooth top inner plane is 0.5 ~ 3.0 mm; The width of outer bearing surface is 0.5 ~ 2.0 mm; Outerplanar width at the bottom of external tooth is 0.5 ~ 3.0 mm; The outerplanar width of outer tooth top is 0.5 ~ 3.0 mm; The width of outer spigot surface is 0.5 ~ 2.0 mm; The width of inner plane at the bottom of external tooth is 0.5 ~ 3.0 mm; The width of outer crest top land is 0.05 ~ 6.0 mm; The width of external tooth bottom surface is 0.05 ~ 6.0 mm; The radius of outer tooth top external arc is 0.20 ~ 0.50mm; The radius of Inner arc at the bottom of external tooth is 0.20 ~ 0.50mm; The radius of the left inside circular arc of outer tooth top is 0.20 ~ 0.50mm; The radius of external arc at the bottom of external tooth is 0.20 ~ 0.50mm; The radius of the outer transition arc of outer crest top land is 0.15 ~ 0.30mm; In outer crest top land, the radius of transition arc is 0.15 ~ 0.30mm; In external tooth bottom surface, the radius of transition arc is 0.15 ~ 0.30mm; Outside external tooth bottom surface, the radius of transition arc is 0.15 ~ 0.30mm; Angle between outer bearing surface and the oil well pipe body axis angle be less than between outer spigot surface and oil well pipe body axis is 2 ~ 6 °.

As preferably, on the longitudinal cross-section of oil well pipe body, the radius of outer transition cambered surface is 12 ~ 20mm, and the central angle number of degrees corresponding to outer transition arcs face are 10 ~ 15 °; The length of the outer secondary conical surface is its tapering of 1.0 ~ 3.0mm is 1:14 ~ 1:16; The radius of outer pair sealing cambered surface is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees corresponding to it are 5 ~ 10 °; The radius of outer primary seal transition cambered surface is 0.0 ~ 2.0mm, and the central angle number of degrees of its correspondence are 165 ~ 175 °; The length in outer main cone face is 1.0 ~ 3.0mm, and its tapering is 1:14 ~ 1:16; The radius of outer primary seal cambered surface is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees corresponding to it are 6 ~ 15 °; The radius of outer dead centre circular arc is 0.1 ~ 1.0mm, and the central angle number of degrees of its correspondence are 45 ~ 60 °; The radius of outer shoulder circular arc is 5.0 ~ 15.0mm, and the central angle number of degrees of its correspondence are 95 ~ 105 °; The length of inwall bore hole plane is 2 ~ 10mm, and the length of transition face is 2 ~ 10mm; The line at outer shoulder circular arc both ends and the supplementary angle number of degrees of inwall bore hole plane angulation are 70 ~ 80 °.

The present invention has the following advantages:

1. the shape of threaded engagement tooth form is improved, have employed the two barb tooth side angle shape of wedge type, the tooth side angle on both sides adopts bearing surface angle to be greater than spigot surface angle, tooth side, screw thread both sides is made to contact completely with tooth side under playing the tight state of high pulling torque machine, and its each profile of tooth tooth side is evenly distributed under interference fit stress, effectively improve its sealing performance and bonding strength.

2. the tooth form bearing surface of form of thread and the pitch of tooth form spigot surface are improved to unequal, and spigot surface pitch is greater than bearing surface pitch, its tooth width increases gradually, alveolus width reduces gradually to occur becoming the wide helicitic texture form of tooth, tooth side lead angle angle simultaneously both it is different, shape is at a certain angle, two tooth sides form the wedge shape conical surface, the profile of tooth of internal and external threads coordinates the wedge thread fit structure just defining the wedge shape conical surface and the wedge shape conical surface, have different significantly from two parallel tooth sides of API buttress thread, can significantly improve its internal and external threads joint coordinate after bonding strength, sealing performance and bending resistance and cross torsional performance.

3. the tooth form bearing surface of form of thread and the pitch of tooth form spigot surface are improved to unequal, and spigot surface pitch is greater than the wide helicitic texture form of change tooth of bearing surface pitch, the flute profile width that internal and external screw thread starts when screwing near end face is all less than space width, make-up is very simple and convenient has stopped thread alternating phenomenon, effectively improves the quality of products and operating efficiency.

4. the wide thread forms of change tooth of bearing surface pitch is greater than owing to have employed spigot surface pitch, various impacts when the difference effectively reduced because of body and box cupling ovality coordinates internal and external threads, particularly serve upper shackle fast and repeatedly go up shackle screw thread and can not occur to scratch and damage phenomenon, significantly improve product percent of pass.

5. adopt wedge type and become the wide Design of Screw Thread structure of tooth and will effectively improve anti-tripping performance, tensile loads performance, the bending resistance of nipple, the high composite bearing ability of effective raising nipple, can provide suitable with body in press drag and bonding strength.

6. at the bottom of the tooth top of screw thread and tooth, have employed the planar design of three different taperings or angle, but not cambered surface, reduce difficulty of processing, reach plane and contact with interplanar, eliminate internal and external threads under the factor impacts such as different ovalitys, improve the impact of interference fit double thread profile of tooth sealing performance.

7. major and minor sealing surface radial diameter hermetically-sealed construction and the cambered surface torque resistant shoulder structure in the likeness in form cucurbit face of two cambered surface and two cambered surface is increased at its thread head.To significantly improve high sealing performance, torque resistant performance and the bending resistance under the counter-bending state of nipple.

8. add its box cupling torque shoulder plane and the interior concordant design of inboard wall of tube body employing simultaneously of box cupling shoulder plane length, effectively can reduce turbulent phenomenon when respective media is passed through in pipeline, energy loss is reduced to minimum.

9. be applicable to very much the Oil/gas Well use of deep-well, ultradeep well, high sealing performance requirement.

Accompanying drawing explanation

Fig. 1 is the structural representation of box cupling body in the present invention.

Fig. 2 is the enlarged diagram of part A in Fig. 1.

Fig. 3 is the enlarged diagram of part B in Fig. 1.

Fig. 4 is the structural representation of oil well pipe body in the present invention.

Fig. 5 is the enlarged diagram of C part in Fig. 4.

Fig. 6 is the enlarged diagram of D part in Fig. 4.

Fig. 7 is the integrated structure schematic diagram of box cupling body and oil well pipe body in the present invention.

Detailed description of the invention

Below in conjunction with specific embodiment, the invention will be further described.

A kind of change tooth wide wedge type box cupling structure, comprise box cupling body 1, the two ends inwall of box cupling body 1 is coupling inner thread section 1.1, is provided with box cupling shoulder 1.2 between two sections of coupling inner thread sections 1.1, on direction by the portion wherein, both ends of box cupling body 1, the facewidth of described coupling inner thread section 1.1 is in increasing setting gradually, the space width of coupling inner thread section 1.1 is in reducing setting gradually, the difference of adjacent two facewidth is equal with adjacent two space widths, the height of each tooth of coupling inner thread section 1.1 is equal, and the tapering of coupling inner thread section 1.1 is 1:16 ~ 1:24, on the longitudinal cross-section of box cupling body 1, each tooth in coupling inner thread section 1.1 is wedge shape, is equipped with barb in the both sides, top of each tooth, the middle top of each tooth in coupling inner thread section 1.1 is interior crest top land 58, the inner side of interior crest top land 58 is provided with interior tooth top inner plane 56, the outside of interior crest top land 58 is provided with interior tooth top outerplanar 53, be connected by transition arc 69 in interior crest top land between interior tooth top inner plane 56 with interior crest top land 58, be connected by the outer transition arc 70 of interior crest top land between interior tooth top outerplanar 53 with interior crest top land 58, it is internal tooth bottom surface 57 in the middle part of teeth groove, internal tooth bottom surface 57 is taper seat, interior crest top land 58 is taper seat, and internal tooth bottom surface 57, the tapering of interior crest top land 58 is equal with the tapering of coupling inner thread section 1.1, the inner side of internal tooth bottom surface 57 is provided with inner plane 51 at the bottom of internal tooth, the outside of internal tooth bottom surface 57 is provided with outerplanar 54 at the bottom of internal tooth, the lateral wall of each tooth is provided with interior spigot surface 55, interior spigot surface 55 is 79 ~ 85 ° with the axis angulation of box cupling body 1, the inside wall of each tooth is provided with interior bearing surface 52, interior bearing surface 52 is 76 ~ 82 ° with the axis angulation of box cupling body 1, be connected by transition arc 68 in internal tooth bottom surface between internal tooth bottom surface 57 with inner plane at the bottom of internal tooth 51, be connected by transition arc 67 outside internal tooth bottom surface between internal tooth bottom surface 57 with outerplanar at the bottom of internal tooth 54, outerplanar 54 at the bottom of internal tooth is connected by external arc 63 at the bottom of internal tooth with between interior spigot surface 55, be connected by interior tooth top Inner arc 64 between interior spigot surface 55 with interior tooth top inner plane 56, inner plane 51 at the bottom of internal tooth is connected by Inner arc 65 at the bottom of internal tooth with between interior bearing surface 52, be connected by interior tooth top external arc 66 between interior bearing surface 52 with interior tooth top outerplanar 53, at the bottom of internal tooth, inner plane 51 is 10 ~ 20 ° with the axis angulation of box cupling body 1, interior tooth top outerplanar 53 is 10 ~ 20 ° with the axis angulation of box cupling body 1, at the bottom of internal tooth, outerplanar 54 is 7 ~ 17 ° with the axis angulation of box cupling body 1, interior tooth top inner plane 56 is 7 ~ 17 ° with the axis angulation of box cupling body 1, and on the longitudinal cross-section of box cupling body 1, the tooth top external arc 66 being positioned at inner terminal position connects with transition cambered surface 82, interior transition cambered surface 82 and the interior secondary conical surface 76 rounding off, the interior secondary conical surface 76 seals cambered surface 84 rounding off with interior pair, interior pair sealing cambered surface 84 and interior primary seal transition cambered surface 86 rounding off, interior primary seal transition cambered surface 86 and interior main cone face 78 rounding off, interior main cone face 78 and interior primary seal cambered surface 88 rounding off, interior primary seal cambered surface 88 and inner vertex circular arc 90 rounding off, inner vertex circular arc 90 and interior shoulder circular arc 92 rounding off, be connected by fillet between interior shoulder circular arc 92 and the endoporus wall of box cupling shoulder 1.2.

As preferably, the tapering of described coupling inner thread section 1.1 is 1:18 ~ 1:20.

As preferably, the number of threads of described coupling inner thread section 1.1 is 12 ~ 30; The first buckle teeth well width of coupling inner thread section 1.1 is 1.8 ~ 3.2mm; The spigot surface pitch of coupling inner thread section 1.1 is 3.96 ~ 9.60mm; The bearing surface pitch of coupling inner thread section 1.1 equals: (internal thread total length deducts 2 times of first buckle teeth groove widths)/(total button number deducts 1); The first buckle teeth of coupling inner thread section 1.1 is wide is: the spigot surface pitch of coupling inner thread section 1.1 deducts the first buckle teeth groove width of coupling inner thread section 1.1; The tooth depth of coupling inner thread section 1.1 is 1.5 ~ 2.5mm.

As preferably, on the longitudinal cross-section of box cupling body 1, the first buckle teeth of coupling inner thread section 1.1 is wide is 1.8 ~ 3.2mm; The tooth depth of each tooth of coupling inner thread section 1.1 is 1.5 ~ 2.5mm; The width of interior tooth top inner plane 56 is 0.5 ~ 3.0 mm; The width of interior bearing surface 52 is 0.5 ~ 2.0 mm; At the bottom of internal tooth, the width of outerplanar 54 is 0.5 ~ 3.0 mm; The width of interior tooth top outerplanar 53 is 0.5 ~ 3.0 mm; The width of interior spigot surface 55 is 0.5 ~ 2.0 mm; At the bottom of internal tooth, the width of inner plane 51 is 0.5 ~ 3.0 mm; The width of interior crest top land 58 is 0.05 ~ 6.0 mm; The width of internal tooth bottom surface 57 is 0.05 ~ 6.0 mm; The radius of interior tooth top external arc 66 is 0.20 ~ 0.50mm; At the bottom of internal tooth, the radius of external arc 63 is 0.20 ~ 0.50mm; The radius of interior tooth top Inner arc 64 is 0.20 ~ 0.50mm; At the bottom of internal tooth, the radius of Inner arc 65 is 0.20 ~ 0.50mm; Outside internal tooth bottom surface, the radius of transition arc 67 is 0.15 ~ 0.30mm; In internal tooth bottom surface, the radius of transition arc 68 is 0.15 ~ 0.30mm; In interior crest top land, the radius of transition arc 69 is 0.15 ~ 0.30mm; In interior crest top land, the radius of transition arc 69 is 0.15 ~ 0.30mm; Angle between interior bearing surface 52 and the axis of box cupling body 1 angle be less than between interior spigot surface 55 and the axis of box cupling body 1 is 2 ~ 6 °.

As preferably, on the longitudinal cross-section of box cupling body 1, the radius of interior transition cambered surface 82 is 12 ~ 20mm, and the central angle number of degrees of interior transition cambered surface 82 correspondence are 10 ~ 15 °; The length of the interior secondary conical surface 76 is 1.0 ~ 3.0mm, and its tapering is 1:14 ~ 1:16; The radius of interior pair sealing cambered surface 84 is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees of interior pair sealing cambered surface 84 correspondence are 5 ~ 10 °; The radius of interior primary seal transition cambered surface 86 is 0.0 ~ 2.0mm, and the central angle number of degrees of interior primary seal transition cambered surface 86 correspondence are 165 ~ 175 °; The length in interior main cone face 78 is 1.0 ~ 3.0mm, and its tapering is 1:14 ~ 1:16; The radius of interior primary seal cambered surface 88 is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees of interior primary seal cambered surface 88 correspondence are 6 ~ 15 °; The radius of inner vertex circular arc 90 is 0.1 ~ 1.0mm, and the central angle number of degrees of inner vertex circular arc 90 correspondence are 45 ~ 60 °; The radius of interior shoulder circular arc 92 is 5.0 ~ 15.0mm, and the central angle number of degrees of interior shoulder circular arc 92 correspondence are 95 ~ 105 °.

A kind of change tooth wide wedged-shaped oil film well casing structure, comprise oil well pipe body 2, the two ends outer wall of oil well pipe body 2 is oil well pipe external thread section 2.1, oil well pipe shoulder 2.2 is provided with between two sections of oil well pipe external thread sections 2.1, on direction by the portion wherein, both ends of oil well pipe body 2, the facewidth of described oil well pipe external thread section 2.1 is in reducing setting gradually, the space width of oil well pipe external thread section 2.1 is in increasing setting gradually, the difference of adjacent two facewidth is equal with adjacent two space widths, the height of each tooth of oil well pipe external thread section 2.1 is equal, the tapering of oil well pipe external thread section 2.1 is 1:16 ~ 1:24, on the longitudinal cross-section of oil well pipe body 2, each tooth on oil well pipe external thread section 2.1 is wedge shape, is equipped with barb in the both sides, top of each tooth, the middle top of each tooth on oil well pipe external thread section 2.1 is outer crest top land 26, the inner side of outer crest top land 26 is provided with outer tooth top inner plane 20, the outside of outer crest top land 26 is provided with outer tooth top outerplanar 23, be connected by transition arc 37 in outer crest top land between outer tooth top inner plane 20 with outer crest top land 26, be connected by the outer transition arc 36 of outer crest top land between outer tooth top outerplanar 23 with outer crest top land 26, it is external tooth bottom surface 27 in the middle part of teeth groove, external tooth bottom surface 27 is taper seat, outer crest top land 26 is taper seat, and outer crest top land 26, the tapering of external tooth bottom surface 27 is equal with the tapering of oil well pipe external thread section 2.1, the inner side of external tooth bottom surface 27 is provided with inner plane 25 at the bottom of external tooth, the outside of external tooth bottom surface 27 is provided with outerplanar 22 at the bottom of external tooth, the lateral wall of each tooth is provided with outer spigot surface 24, outer spigot surface 24 is 79 ~ 85 ° with the axis angulation of oil well pipe body 2, the inside wall of each tooth is provided with outer bearing surface 21, outer bearing surface 21 is 76 ~ 82 ° with the axis angulation of oil well pipe body 2, be connected by transition arc 38 in external tooth bottom surface between external tooth bottom surface 27 with inner plane at the bottom of external tooth 25, be connected by transition arc 39 outside external tooth bottom surface between external tooth bottom surface 27 with outerplanar at the bottom of external tooth 22, outerplanar 22 at the bottom of external tooth is connected by external arc 35 at the bottom of external tooth with between outer bearing surface 21, be connected by the left inside circular arc 34 of outer tooth top between outer bearing surface 21 with outer tooth top inner plane 20, inner plane 25 at the bottom of external tooth is connected by Inner arc 33 at the bottom of external tooth with between outer spigot surface 24, be connected by outer tooth top external arc 32 between outer spigot surface 24 with outer tooth top outerplanar 23, at the bottom of internal tooth, inner plane 51 is 10 ~ 20 ° with the axis angulation of box cupling body 1, outer tooth top outerplanar 23 is 10 ~ 20 ° with the axis angulation of oil well pipe body 2, at the bottom of external tooth, outerplanar 22 is 7 ~ 17 ° with the axis angulation of oil well pipe body 2, outer tooth top inner plane 20 is 7 ~ 17 ° with the axis angulation of oil well pipe body 2, and on the longitudinal cross-section of oil well pipe body 2, be positioned at external arc 35 at the bottom of the external tooth of outermost end and outer transition cambered surface 83 rounding off, outer transition cambered surface 83 and the outer secondary conical surface 77 rounding off, the outer secondary conical surface 77 seals cambered surface 85 rounding off with outer pair, outer pair sealing cambered surface 85 and outer primary seal transition cambered surface 87 rounding off, outer primary seal transition cambered surface 87 and outer main cone face 79 rounding off, outer main cone face 79 and outer primary seal cambered surface 89 rounding off, outer primary seal cambered surface 89 and outer dead centre circular arc 91 rounding off, outer dead centre circular arc 91 and outer shoulder circular arc 93 rounding off, outer shoulder circular arc 93 connects with inwall bore hole plane 81, inwall bore hole plane 81 connects with transition face 97, transition face 97 connects with the endoporus wall of oil well pipe external thread section 2.1.

As preferably, the tapering of described oil well pipe external thread section 2.1 is 1:18 ~ 1:20.

As preferably, the number of threads of described oil well pipe external thread section 2.1 is 12 ~ 30; The first buckle teeth of oil well pipe external thread section 2.1 is wide is 1.8 ~ 3.2mm; The spigot surface pitch of oil well pipe external thread section 2.1 is 3.96 ~ 9.60mm; The bearing surface pitch of oil well pipe external thread section 2.1 is: (it is wide that external screw thread total length deducts 2 times of first buckle teeth)/(total button number deducts 1); The first buckle teeth groove width of oil well pipe external thread section 2.1 is: it is wide that outer spigot surface pitch deducts first buckle teeth; The tooth depth of oil well pipe external thread section 2.1 is 1.5 ~ 2.5mm.

As preferably, on the longitudinal cross-section of oil well pipe body 2, the first buckle teeth of oil well pipe external thread section 2.1 is wide is 1.8 ~ 3.2mm; The tooth depth of each tooth of oil well pipe external thread section 2.1 is 1.5 ~ 2.5mm; The width of outer tooth top inner plane 20 is 0.5 ~ 3.0 mm; The width of outer bearing surface 21 is 0.5 ~ 2.0 mm; At the bottom of external tooth, the width of outerplanar 22 is 0.5 ~ 3.0 mm; The width of outer tooth top outerplanar 23 is 0.5 ~ 3.0 mm; The width of outer spigot surface 24 is 0.5 ~ 2.0 mm; At the bottom of external tooth, the width of inner plane 25 is 0.5 ~ 3.0 mm; The width of outer crest top land 26 is 0.05 ~ 6.0 mm; The width of external tooth bottom surface 27 is 0.05 ~ 6.0 mm; The radius of outer tooth top external arc 32 is 0.20 ~ 0.50mm; At the bottom of external tooth, the radius of Inner arc 33 is 0.20 ~ 0.50mm; The radius of the left inside circular arc 34 of outer tooth top is 0.20 ~ 0.50mm; At the bottom of external tooth, the radius of external arc 35 is 0.20 ~ 0.50mm; The radius of the outer transition arc 36 of outer crest top land is 0.15 ~ 0.30mm; In outer crest top land, the radius of transition arc 37 is 0.15 ~ 0.30mm; In external tooth bottom surface, the radius of transition arc 38 is 0.15 ~ 0.30mm; Outside external tooth bottom surface, the radius of transition arc 39 is 0.15 ~ 0.30mm; Angle between outer bearing surface 21 and the oil well pipe body 2 axis angle be less than between outer spigot surface 24 and oil well pipe body 2 axis is 2 ~ 6 °.

As preferably, on the longitudinal cross-section of oil well pipe body 2, the radius of outer transition cambered surface 83 is 12 ~ 20mm, and the central angle number of degrees of outer transition cambered surface 83 correspondence are 10 ~ 15 °; The length of the outer secondary conical surface 77 is its tapering of 1.0 ~ 3.0mm is 1:14 ~ 1:16; The radius of outer pair sealing cambered surface 85 is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees corresponding to it are 5 ~ 10 °; The radius of outer primary seal transition cambered surface 87 is 0.0 ~ 2.0mm, and the central angle number of degrees of its correspondence are 165 ~ 175 °; The length in outer main cone face 79 is 1.0 ~ 3.0mm, and its tapering is 1:14 ~ 1:16; The radius of outer primary seal cambered surface 89 is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees corresponding to it are 6 ~ 15 °; The radius of outer dead centre circular arc 91 is 0.1 ~ 1.0mm, and the central angle number of degrees of its correspondence are 45 ~ 60 °; The radius of outer shoulder circular arc 93 is 5.0 ~ 15.0mm, and the central angle number of degrees of its correspondence are 95 ~ 105 °; The length of inwall bore hole plane 81 is 2 ~ 10mm, and the length of transition face 97 is 2 ~ 10mm; The line at outer shoulder circular arc 93 both ends and the supplementary angle number of degrees of inwall bore hole plane 81 angulation are 70 ~ 80 °.

During use, oil well pipe body 2 and oil well pipe body 2 carry out somely being connected to form casing string with the form of being threaded by box cupling body 1, casing string inside becomes the overall space passage of a UNICOM, the power that extraneous high strength complexity can be born in inner passage applies and does not reveal or damage, and meets the requirement of oil gas field production and application.

Parameter designing of the present invention requires:

Coupling inner thread section 1.1 is identical with the thread parameter major part of oil well pipe external thread section 2.1, and just tolerance is different, for meeting the interference fit requirement between internal and external threads profile of tooth.

1. oil well pipe external thread section 2.1 external screw thread total length requires identical with coupling inner thread section 1.1 internal thread overall length dimension, length is all within the scope of 50 ~ 160mm, different according to pipe wall thickness and external diameter, can with reference to API SPEC 5B " processing of sleeve pipe, oil pipe and line pipe thread, measurement and inspection specification ".

2. oil well pipe external thread section 2.1, oil well pipe external thread section 2.1 tooth number according to full flight length scope and tooth is wide and the size of pitch is determined preferably to control between 12 ~ 30 teeth the concrete tooth number of screw thread, selected amount when being screw thread comprehensive Design.

3. oil well pipe external thread section 2.1 is identical with the tapering of coupling inner thread section 1.1.

4. the oil well pipe external thread section 2.1 first buckle teeth facewidth is identical with the width requirement of coupling inner thread section 1.1 first buckle teeth groove width.The multiple of the oil well pipe external thread section 2.1 first buckle teeth facewidth requires identical with the multiple of coupling inner thread section 1.1 first buckle teeth groove width.The outer spigot surface pitch of oil well pipe external thread section 2.1 requires identical with the interior spigot surface pitch of coupling inner thread section 1.1.The outer bearing surface pitch 15 of oil well pipe external thread section 2.1 requires identical with the interior bearing surface pitch 46 of coupling inner thread section 1.1.

5. the oil well pipe external thread section 2.1 first buckle teeth facewidth is identical with the width requirement of coupling inner thread section 1.1 first buckle teeth groove width.Its follow-up external screw thread tooth width recruitment and follow-up internal thread alveolus width recruitment require both it identical.

6. the outer bearing surface pitch of oil well pipe external thread section 2.1 requires identical with the interior bearing surface pitch of coupling inner thread section 1.1.

7. the first buckle teeth groove width calculating formula of oil well pipe external thread section 2.1 is: the outside buckle teeth facewidth width of the outer spigot surface pitch-oil well pipe external thread section 2.1 of oil well pipe external thread section 2.1, its follow-up alveolus width will reduce gradually, its decrease is the difference that bearing surface pitch deducts spigot surface pitch, but can not be less than 0.02mm.The first buckle teeth facewidth calculating formula of coupling inner thread section 1.1 is: the interior first buckle teeth groove width width of the interior spigot surface pitch-coupling inner thread section 1.1 of coupling inner thread section 1.1, identical with it.

8. the recruitment that the externally threaded tooth of oil well pipe external thread section 2.1 is wide is identical with alveolus width reduction, outer bearing surface pitch and the outer spigot surface pitch of oil well pipe external thread section 2.1 all remain unchanged, and what gradually change is tooth width and alveolus width, ensure that screwing of internal and external threads is smooth and easy without interfering;

The recruitment that the alveolus of the internal thread of coupling inner thread section 1.1 is wide is identical with tooth width decrease, the interior bearing surface pitch of coupling inner thread section 1.1 and the interior spigot surface pitch of coupling inner thread section 1.1 all remain unchanged, and what gradually change is tooth width and alveolus width, ensure that screwing of internal and external threads is smooth and easy without interfering.Ensure that its internal and external threads proper engagement.

9. the tooth depth of oil well pipe external thread section 2.1 is identical with the tooth depth of coupling inner thread section 1.1, and they are all between 1.5mm ~ 2.5mm, parallel with at the bottom of tooth at the bottom of tooth.

10. the angle between outer bearing surface 21 and oil well pipe body 2 axis is less than the angle between outer spigot surface 24 and oil well pipe body 2 axis, keeps the difference of 2 ~ 6 ° between them.Angle between interior bearing surface 52 and the axis of box cupling body 1 is less than the angle between interior spigot surface 55 and the axis of box cupling body 1, and keep the difference of 2 ~ 6 ° between them, both are identical, forms wedge shape tooth form angle.

Angle between 11. outer tooth top inner planes 20 and oil well pipe body 2 axis, outerplanar 22 at the bottom of external tooth and the angle between oil well pipe body 2 axis, angle between the axis of inner plane 51 and box cupling body 1 at the bottom of internal tooth, angle between interior tooth top outerplanar 53 and the axis of box cupling body 1 is identical, angle between outer tooth top outerplanar 23 and oil well pipe body 2 axis, inner plane 25 at the bottom of external tooth and the angle between oil well pipe body 2 axis, angle between the axis of outerplanar 54 and box cupling body 1 at the bottom of internal tooth, angle between interior tooth top inner plane 56 and the axis of box cupling body 1 is identical.Outerplanar 22 at the bottom of external tooth is identical with the angle at the bottom of the angle between oil well pipe body 2 axis, the angle between outer tooth top outerplanar 23 and oil well pipe body 2 axis, the angle between interior tooth top inner plane 56 and the axis of box cupling body 1, internal tooth between outerplanar 54 and the axis of box cupling body 1.Outerplanar 22 at the bottom of external tooth is identical with the angle at the bottom of the angle between oil well pipe body 2 axis, the angle between outer tooth top inner plane 20 and oil well pipe body 2 axis, the angle between interior tooth top outerplanar 53 and the axis of box cupling body 1, internal tooth between inner plane 51 and the axis of box cupling body 1.

Radius and their corresponding center of circle angle elements of 12. outer tooth top external arc 32 and outer tooth top Inner arc 34 are identical, radius and their corresponding center of circle angle elements of external arc 63 at the bottom of internal tooth and Inner arc at the bottom of internal tooth 65 are identical, and the arc radius of outer tooth top external arc 32 and outer tooth top Inner arc 34 is greater than Inner arc 65 radius 0.05 ~ 0.20mm at the bottom of external arc 63 at the bottom of internal tooth and internal tooth.Simultaneously, radius and their corresponding center of circle angle elements of Inner arc 33 at the bottom of external tooth and external arc at the bottom of external tooth 35 are identical, radius and their corresponding center of circle angle elements of interior tooth top Inner arc 64 and interior tooth top external arc 66 are identical, and at the bottom of Inner arc 33 at the bottom of external tooth and external tooth, the arc radius of external arc 35 is greater than interior tooth top Inner arc 64 and interior tooth top external arc 66 radius 0.05 ~ 0.20mm.The touching damage occurred when can eliminate its interference fit like this scratches phenomenon.

In the outer transition arc 36 of 13. outer crest top lands, outer crest top land, transition arc 37 is all identical with transition arc 70 radius outside transition arc 69, interior crest top land in interior crest top land with transition arc in transition arc 67, internal tooth bottom surface outside transition arc 39, internal tooth bottom surface outside transition arc 38, external tooth bottom surface in external tooth bottom surface 68, and their radius is 0.20mm ~ 0.50mm.

In 14. primary seal cambered surface 88 inner end to box cupling shoulder 1.2 endoporus wall between distance and outer primary seal cambered surface 89 outer end to oil well pipe external thread section 2.1 endoporus wall between required distance equal, concordant with inwall bore hole plane 81 to reach box cupling shoulder plane, keep same plane, reduce the passage resistance of fluid in body.

In 15., with outer main cone face 79, the secondary conical surface 76 requires that length, tapering are equal with the outer secondary conical surface 77, interior main cone face 78.The central angle number of degrees of outer primary seal cambered surface 89 and the outer pair sealing radius of cambered surface 85, arc length and correspondence are all equal, and interior main cone face 78 is all identical with tapering with the length of the interior secondary conical surface 76.

In 16., the radial internal diameter of secondary sealing cambered surface 84 is less than the radial outer diameter of outer pair sealing cambered surface 85, the radial internal diameter of interior primary seal cambered surface 88 is less than the radial outer diameter of outer primary seal cambered surface 89, its magnitude of interference between the two keeps identical and should be 0.2 ~ 1.0mm scope, meet the requirement of radial diameter interference fit, reach the high sealing performance requirement under counter-bending state.

In 17., shoulder angle 80 is greater than between outer land fillet degree 81, its deviation all controls the scope at 0.5 ~ 1.5 °, be best with deviation 0.5 ~ 1.0 °, meet the plastic deformation state that inside and outside shoulder causes in the tight situation of machine and be issued to interference fit, improve its torque resistant performance requirement.

In 18., transition cambered surface 82 is more than or equal to outer transition cambered surface 83, prevents any interference.

In 19., secondary sealing cambered surface 84 is equal with the radius requirement that outer pair seals cambered surface 85, and their tapering requires as 1:8 ~ 1:14; Interior primary seal cambered surface 88 is equal with the radius requirement of outer primary seal cambered surface 89, and their tapering requires to be 1:8 ~ 1:14.

In 20., primary seal transition cambered surface 86 and outer primary seal transition cambered surface 87 require to seamlessly transit with phase trimming, must not have the phenomenon that any interference effect coordinates.

The radius of 21. inner vertex circular arcs 90 is less than or equal to the radius of outer dead centre circular arc 91, and its Deviation Control, in the scope of 0.1 ~ 0.2mm, is intended meeting its summit after interference fit and is not damaged.

In 22., shoulder circular arc 92 is equal with the radius requirement of outer shoulder circular arc 93, and the tapering of interior major-minor sealing cambered surface 84 requires identical with the tapering that outer major-minor seals the tapering of cambered surface 89, and tolerance fit controls as interference fit requirement.

Concrete operations are as follows:

First by external threaded surface uniform application one deck oil dedicated thread compound of oil well pipe body 2, again any one end of box cupling 1 is first inserted on oil well pipe body 2 external screw thread, the external screw thread of the internal thread of box cupling body 1 and oil well pipe body 2 should be carried out make-up when being inserted in, light and slow internal thread tooth top should be contacted with at the bottom of external screw thread tooth during hitch, due to the unequal threaded engagement form of the pitch that have employed tooth form bearing surface and tooth form spigot surface, the tooth of its box cupling end and body end thread is wide, and to be less than alveolus wide be that uniform pitch becomes the wide form of thread of tooth, its make-up is very convenient and simple, substantially thread alternating phenomenon can not be there is.First be inserted in 2 ~ 4 button left and right, start manually hand-tight very light when screwing internal and external threads, when manually not rotating and hand-tightly to complete.Because the tolerance of some parameters such as tapering, pitch, tooth form, tooth depth of screw thread is different, hand-tight rear thread connects to twist receives position, also needs to use further high pulling torque/high moment of torsion to carry out machine and twists when connecing, should adopt at a slow speed or carry out slowly.Now in reach, be issued to the interference fit between tooth form in the situation of uniform stressed at the bottom of the bearing surface of each tooth and spigot surface and tooth top tooth, tooth form sealing structure performance significantly improves, and the impact that the different double threads of body and box cupling ovality coordinate is very little.Simultaneously, face between the intersecting lens of the end face of the face between the intersecting lens of the end face of internal tooth bottom surface 57 and box cupling shoulder 1.2 and the endoporus wall of box cupling shoulder 1.2, external tooth bottom surface 27 and coupling inner thread section 1.1 and coupling inner thread section 1.1 inner hole wall reaches interference fit, considerably increases the ability of its high resistance torsional performance and compressive load ability and tensile load.Its nipple is made to have high sealing performance, high composite bearing ability.Machine twist connect after detect gap length inside and outside it after shoulder interference fit with ultra-thin special blade, any gap must not be had, the point of a knife of blade can not be inserted circumferentially to detect.

Its box cupling body 1 and oil well pipe body 2 are closely cooperate for benchmark with virtual middle line by same fastening method, reach oil well pipe body 2 and oil well pipe body 2 and are undertaken by box cupling body 1 that some connecting-types become oil, casing string meets the requirement of oil gas field production and application.When going into the well in oil field, its connector machine is one by one close to the oil casing that direct type becomes thousands of meters.

Operating principle of the present invention is as follows:

Body and body carry out somely being connected to form casing string with the form of being threaded by box cupling, casing string inside becomes the overall space passage of a UNICOM, the power that extraneous high strength complexity can be born in inner passage applies and does not reveal or damage, and meets the requirement of oil gas field production and application.

Claims (10)

1. anti-leak high sealability becomes a tooth wide wedge type box cupling structure, and comprise box cupling body (1), the two ends inwall of box cupling body (1) is coupling inner thread section (1.1), is provided with box cupling shoulder (1.2) between two sections of coupling inner thread sections (1.1), it is characterized in that: on the direction by the portion wherein, both ends of box cupling body (1), the facewidth of described coupling inner thread section (1.1) is in increasing setting gradually, the space width of coupling inner thread section (1.1) is in reducing setting gradually, the difference of adjacent two facewidth is equal with the difference of adjacent two space widths, the height of each tooth of coupling inner thread section (1.1) is equal, and the tapering of coupling inner thread section (1.1) is 1:16 ~ 1:24, on the longitudinal cross-section of box cupling body (1), each tooth in coupling inner thread section (1.1) is wedge shape, is equipped with barb in the both sides, top of each tooth, the middle top of each tooth in coupling inner thread section (1.1) is interior crest top land (58), the inner side of interior crest top land (58) is provided with interior tooth top inner plane (56), the outside of interior crest top land (58) is provided with interior tooth top outerplanar (53), interior tooth top inner plane (56) is connected by transition arc (69) in interior crest top land with between interior crest top land (58), interior tooth top outerplanar (53) is connected by the outer transition arc (70) of interior crest top land with between interior crest top land (58), it is internal tooth bottom surface (57) in the middle part of teeth groove, internal tooth bottom surface (57) is taper seat, interior crest top land (58) is taper seat, and internal tooth bottom surface (57), the tapering of interior crest top land (58) is equal with the tapering of coupling inner thread section (1.1), the inner side of internal tooth bottom surface (57) is provided with inner plane at the bottom of internal tooth (51), the outside of internal tooth bottom surface (57) is provided with outerplanar at the bottom of internal tooth (54), the inside wall of each tooth is provided with interior spigot surface (55), interior spigot surface (55) is 79 ~ 85 ° with the axis angulation of box cupling body (1), the lateral wall of each tooth is provided with interior bearing surface (52), interior bearing surface (52) is 76 ~ 82 ° with the axis angulation of box cupling body (1), be connected by transition arc (68) in internal tooth bottom surface between internal tooth bottom surface (57) with inner plane at the bottom of internal tooth (51), be connected by transition arc (67) outside internal tooth bottom surface between internal tooth bottom surface (57) with outerplanar at the bottom of internal tooth (54), be connected by external arc (63) at the bottom of internal tooth between outerplanar at the bottom of internal tooth (54) with interior spigot surface (55), be connected by interior tooth top Inner arc (64) between interior spigot surface (55) with interior tooth top inner plane (56), be connected by Inner arc (65) at the bottom of internal tooth between inner plane at the bottom of internal tooth (51) with interior bearing surface (52), be connected by interior tooth top external arc (66) between interior bearing surface (52) with interior tooth top outerplanar (53), inner plane at the bottom of internal tooth (51) is 10 ~ 20 ° with the axis angulation of box cupling body (1), interior tooth top outerplanar (53) is 10 ~ 20 ° with the axis angulation of box cupling body (1), outerplanar at the bottom of internal tooth (54) is 7 ~ 17 ° with the axis angulation of box cupling body (1), interior tooth top inner plane (56) is 7 ~ 17 ° with the axis angulation of box cupling body (1), and on the longitudinal cross-section of box cupling body (1), the tooth top external arc (66) being positioned at inner terminal position connects with transition cambered surface (82), interior transition cambered surface (82) and the interior secondary conical surface (76) rounding off, the interior secondary conical surface (76) and interior pair seal cambered surface (84) rounding off, interior pair sealing cambered surface (84) and interior primary seal transition cambered surface (86) rounding off, interior primary seal transition cambered surface (86) and interior main cone face (78) rounding off, interior main cone face (78) and interior primary seal cambered surface (88) rounding off, interior primary seal cambered surface (88) and inner vertex circular arc (90) rounding off, inner vertex circular arc (90) and interior shoulder circular arc (92) rounding off, interior shoulder circular arc (92) is connected by fillet with between the endoporus wall of box cupling shoulder (1.2).

2. anti-leak high sealability as claimed in claim 1 becomes tooth wide wedge type box cupling structure, it is characterized in that: the tapering of described coupling inner thread section (1.1) is 1:18 ~ 1:20.

3. anti-leak high sealability as claimed in claim 1 becomes tooth wide wedge type box cupling structure, it is characterized in that: the number of threads of described coupling inner thread section (1.1) is 12 ~ 30; The first buckle teeth well width of coupling inner thread section (1.1) is 1.8 ~ 3.2mm; The spigot surface pitch of coupling inner thread section (1.1) is 3.96 ~ 9.60mm; The bearing surface pitch of coupling inner thread section (1.1) equals: (internal thread total length deducts 2 times of first buckle teeth groove widths)/(total button number deducts 1); The first buckle teeth of coupling inner thread section (1.1) is wide is: the spigot surface pitch of coupling inner thread section (1.1) deducts the first buckle teeth groove width of coupling inner thread section (1.1); The tooth depth of coupling inner thread section (1.1) is 1.5 ~ 2.5mm.

4. anti-leak high sealability as claimed in claim 1 becomes tooth wide wedge type box cupling structure, and it is characterized in that: on the longitudinal cross-section of box cupling body (1), the first buckle teeth of coupling inner thread section (1.1) is wide is 1.8 ~ 3.2mm; The tooth depth of each tooth of coupling inner thread section (1.1) is 1.5 ~ 2.5mm; The width of interior tooth top inner plane (56) is 0.5 ~ 3.0 mm; The width of interior bearing surface (52) is 0.5 ~ 2.0 mm; The width of outerplanar at the bottom of internal tooth (54) is 0.5 ~ 3.0 mm; The width of interior tooth top outerplanar (53) is 0.5 ~ 3.0 mm; The width of interior spigot surface (55) is 0.5 ~ 2.0 mm; The width of inner plane at the bottom of internal tooth (51) is 0.5 ~ 3.0 mm; The width of interior crest top land (58) is 0.05 ~ 6.0 mm; The width of internal tooth bottom surface (57) is 0.05 ~ 6.0 mm; The radius of interior tooth top external arc (66) is 0.20 ~ 0.50mm; The radius of external arc at the bottom of internal tooth (63) is 0.20 ~ 0.50mm; The radius of interior tooth top Inner arc (64) is 0.20 ~ 0.50mm; The radius of Inner arc at the bottom of internal tooth (65) is 0.20 ~ 0.50mm; Outside internal tooth bottom surface, the radius of transition arc (67) is 0.15 ~ 0.30mm; In internal tooth bottom surface, the radius of transition arc (68) is 0.15 ~ 0.30mm; In interior crest top land, the radius of transition arc (69) is 0.15 ~ 0.30mm; In interior crest top land, the radius of transition arc (69) is 0.15 ~ 0.30mm; Angle between the axis that angle between the axis of interior bearing surface (52) and box cupling body (1) is less than interior spigot surface (55) and box cupling body (1) is 2 ~ 6 °.

5. anti-leak high sealability as claimed in claim 1 becomes tooth wide wedge type box cupling structure, it is characterized in that: on the longitudinal cross-section of box cupling body (1), the radius of interior transition cambered surface (82) is 12 ~ 20mm, and the central angle number of degrees of interior transition cambered surface (82) correspondence are 10 ~ 15 °; The length of the interior secondary conical surface (76) is 1.0 ~ 3.0mm, and its tapering is 1:14 ~ 1:16; The radius of interior pair sealing cambered surface (84) is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees of interior pair sealing cambered surface (84) correspondence are 5 ~ 10 °; The radius of interior primary seal transition cambered surface (86) is 0.0 ~ 2.0mm, and the central angle number of degrees of interior primary seal transition cambered surface (86) correspondence are 10 ~ 15 °; The length of interior main cone face (78) is 1.0 ~ 3.0mm, and its tapering is 1:14 ~ 1:16; The radius of interior primary seal cambered surface (88) is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees of interior primary seal cambered surface (88) correspondence are 6 ~ 15 °; The radius of inner vertex circular arc (90) is 0.1 ~ 1.0mm, and the central angle number of degrees that inner vertex circular arc (90) is corresponding are 45 ~ 60 °; The radius of interior shoulder circular arc (92) is 5.0 ~ 15.0mm, and the central angle number of degrees of interior shoulder circular arc (92) correspondence are 95 ~ 105 °.

6. an anti-leak high sealability becomes tooth wide wedge type box cupling structure oil well pipe structure, comprise oil well pipe body (2), the two ends outer wall of oil well pipe body (2) is oil well pipe external thread section (2.1), oil well pipe shoulder (2.2) is provided with between two sections of oil well pipe external thread sections (2.1), on direction by the portion wherein, both ends of oil well pipe body (2), the facewidth of described oil well pipe external thread section (2.1) is in reducing setting gradually, the space width of oil well pipe external thread section (2.1) is in increasing setting gradually, the difference of adjacent two facewidth is equal with the difference of adjacent two space widths, the height of each tooth of oil well pipe external thread section (2.1) is equal, the tapering of oil well pipe external thread section (2.1) is 1:16 ~ 1:24, on the longitudinal cross-section of oil well pipe body (2), each tooth on oil well pipe external thread section (2.1) is wedge shape, is equipped with barb in the both sides, top of each tooth, the middle top of each tooth on oil well pipe external thread section (2.1) is outer crest top land (26), the inner side of outer crest top land (26) is provided with outer tooth top inner plane (20), the outside of outer crest top land (26) is provided with outer tooth top outerplanar (23), outer tooth top inner plane (20) is connected by transition arc (37) in outer crest top land with between outer crest top land (26), outer tooth top outerplanar (23) is connected by the outer transition arc (36) of outer crest top land with between outer crest top land (26), it is external tooth bottom surface (27) in the middle part of teeth groove, external tooth bottom surface (27) is taper seat, outer crest top land (26) is taper seat, and outer crest top land (26), the tapering of external tooth bottom surface (27) is equal with the tapering of oil well pipe external thread section (2.1), the inner side of external tooth bottom surface (27) is provided with inner plane at the bottom of external tooth (25), the outside of external tooth bottom surface (27) is provided with outerplanar at the bottom of external tooth (22), the lateral wall of each tooth is provided with outer spigot surface (24), outer spigot surface (24) is 79 ~ 85 ° with the axis angulation of oil well pipe body (2), the inside wall of each tooth is provided with outer bearing surface (21), outer bearing surface (21) is 76 ~ 82 ° with the axis angulation of oil well pipe body (2), be connected by transition arc (38) in external tooth bottom surface between external tooth bottom surface (27) with inner plane at the bottom of external tooth (25), be connected by transition arc (39) outside external tooth bottom surface between external tooth bottom surface (27) with outerplanar at the bottom of external tooth (22), be connected by external arc (35) at the bottom of external tooth between outerplanar at the bottom of external tooth (22) with outer bearing surface (21), be connected by the left inside circular arc of outer tooth top (34) between outer bearing surface (21) with outer tooth top inner plane (20), be connected by Inner arc (33) at the bottom of external tooth between inner plane at the bottom of external tooth (25) with outer spigot surface (24), be connected by outer tooth top external arc (32) between outer spigot surface (24) with outer tooth top outerplanar (23), inner plane at the bottom of external tooth (25) is 10 ~ 20 ° with the axis angulation of oil well pipe body (2), outer tooth top outerplanar (23) is 10 ~ 20 ° with the axis angulation of oil well pipe body (2), outerplanar at the bottom of external tooth (22) is 7 ~ 17 ° with the axis angulation of oil well pipe body (2), outer tooth top inner plane (20) is 7 ~ 17 ° with the axis angulation of oil well pipe body (2), and on the longitudinal cross-section of oil well pipe body (2), be positioned at external arc (35) at the bottom of the external tooth of inner terminal and outer transition cambered surface (83) rounding off, outer transition cambered surface (83) and the outer secondary conical surface (77) rounding off, the outer secondary conical surface (77) and outer pair seal cambered surface (85) rounding off, outer pair sealing cambered surface (85) and outer primary seal transition cambered surface (87) rounding off, outer primary seal transition cambered surface (87) and outer main cone face (79) rounding off, outer main cone face (79) and outer primary seal cambered surface (89) rounding off, outer primary seal cambered surface (89) and outer dead centre circular arc (91) rounding off, outer dead centre circular arc (91) and outer shoulder circular arc (93) rounding off, outer shoulder circular arc (93) connects with inwall bore hole plane (81), inwall bore hole plane (81) connects with transition face (97), transition face (97) connects with the endoporus wall of oil well pipe external thread section (2.1).

7. anti-leak high sealability as claimed in claim 6 becomes tooth wide wedge type box cupling structure oil well pipe structure, it is characterized in that: the tapering of described oil well pipe external thread section (2.1) is 1:18 ~ 1:20.

8. anti-leak high sealability as claimed in claim 6 becomes tooth wide wedge type box cupling structure oil well pipe structure, it is characterized in that: the number of threads of described oil well pipe external thread section (2.1) is 12 ~ 30; The first buckle teeth of oil well pipe external thread section (2.1) is wide is 1.8 ~ 3.2mm; The spigot surface pitch of oil well pipe external thread section (2.1) is 3.96 ~ 9.60mm; The bearing surface pitch of oil well pipe external thread section (2.1) is: (it is wide that external screw thread total length deducts 2 times of first buckle teeth)/(total button number deducts 1); The first buckle teeth groove width of oil well pipe external thread section (2.1) is: it is wide that outer spigot surface pitch deducts first buckle teeth; The tooth depth of oil well pipe external thread section (2.1) is 1.5 ~ 2.5mm.

9. anti-leak high sealability as claimed in claim 6 becomes tooth wide wedge type box cupling structure oil well pipe structure, and it is characterized in that: on the longitudinal cross-section of oil well pipe body (2), the first buckle teeth of oil well pipe external thread section (2.1) is wide is 1.8 ~ 3.2mm; The tooth depth of each tooth of oil well pipe external thread section (2.1) is 1.5 ~ 2.5mm; The width of outer tooth top inner plane (20) is 0.5 ~ 3.0 mm; The width of outer bearing surface (21) is 0.5 ~ 2.0 mm; The width of outerplanar at the bottom of external tooth (22) is 0.5 ~ 3.0 mm; The width of outer tooth top outerplanar (23) is 0.5 ~ 3.0 mm; The width of outer spigot surface (24) is 0.5 ~ 2.0 mm; The width of inner plane at the bottom of external tooth (25) is 0.5 ~ 3.0 mm; The width of outer crest top land (26) is 0.05 ~ 6.0 mm; The width of external tooth bottom surface (27) is 0.05 ~ 6.0 mm; The radius of outer tooth top external arc (32) is 0.20 ~ 0.50mm; The radius of Inner arc at the bottom of external tooth (33) is 0.20 ~ 0.50mm; The radius of the left inside circular arc of outer tooth top (34) is 0.20 ~ 0.50mm; The radius of external arc at the bottom of external tooth (35) is 0.20 ~ 0.50mm; The radius of the outer transition arc (36) of outer crest top land is 0.15 ~ 0.30mm; In outer crest top land, the radius of transition arc (37) is 0.15 ~ 0.30mm; In external tooth bottom surface, the radius of transition arc (38) is 0.15 ~ 0.30mm; Outside external tooth bottom surface, the radius of transition arc (39) is 0.15 ~ 0.30mm; Angle between outer bearing surface (21) and oil well pipe body (2) the axis angle be less than between outer spigot surface (24) and oil well pipe body (2) axis is 2 ~ 6 °.

10. anti-leak high sealability as claimed in claim 6 becomes tooth wide wedge type box cupling structure oil well pipe structure, it is characterized in that: on the longitudinal cross-section of oil well pipe body (2), the radius of outer transition cambered surface (83) is 12 ~ 20mm, and the central angle number of degrees of outer transition cambered surface (83) correspondence are 10 ~ 15 °; The length of the outer secondary conical surface (77) is its tapering of 1.0 ~ 3.0mm is 1:14 ~ 1:16; The radius of outer pair sealing cambered surface (85) is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees corresponding to it are 5 ~ 10 °; The radius of outer primary seal transition cambered surface (87) is 0.0 ~ 2.0mm, and the central angle number of degrees of its correspondence are 165 ~ 175 °; The length in outer main cone face 79 is 1.0 ~ 3.0mm, and its tapering is 1:14 ~ 1:16; The radius of outer primary seal cambered surface (89) is 10 ~ 20mm, and its arc length is 3 ~ 8mm, and the central angle number of degrees corresponding to it are 6 ~ 15 °; The radius of outer dead centre circular arc (91) is 0.1 ~ 1.0mm, and the central angle number of degrees of its correspondence are 45 ~ 60 °; The radius of outer shoulder circular arc (93) is 5.0 ~ 15.0mm, and the central angle number of degrees of its correspondence are 95 ~ 105 °; The length of inwall bore hole plane (81) is 2 ~ 10mm, and the length of transition face (97) is 2 ~ 10mm; The outer line at shoulder circular arc (93) both ends and the supplementary angle number of degrees of inwall bore hole plane (81) angulation are 70 ~ 80 °.