A kind of screw drilling tool motor stator
Technical field
The present invention relates to a kind of motor stator that is used for oil, gas drilling field and helicoid hydraulic motor configuration.
Background technology
Screw drilling tool motor is the most widely used at present a kind of mud motor, is mainly used in the deflecting of directional well, horizontal well and turns round the orientation construction, and a part also is used for straight well left-hand thread or sidetracking operation.U.S.'s the mid-50 begins to develop helicoid hydraulic motor, is used in 1962 producing, and the enlightening that has of different manufacturers production is received drilling tool (Smith company), Navi-Drill (Christensen company) and Persian drilling tool, and its basic principle all is based on positive displacement motor.The motor stator of traditional helicoid hydraulic motor, as shown in Figure 1, be that the vulcanization of rubber is formed rubber bushing (2) in steel pipe housing (1), the endoporus of steel pipe housing is circular, the inner surface of rubber bushing is a spiral camber, thereby the radial section thickness of rubber bushing ten minutes is inhomogeneous, the stator of this helicoid hydraulic motor is when the rotor rotary work, the heat that spin friction produces accumulates in the thick part of rubber easily, make the bigger of herein rubber swelling amount than other positions, like this rotor portion when work within it, cause the stator premature failure easily, thereby reduce the operating efficiency and the useful life of screw drilling tool motor.Chinese patent 200820108496.4 discloses a kind of pre-profile formula screw drilling tool motor stator, its radial section structure as shown in Figure 2, on the normal orientation of the inner chamber curve of stator, the thickness of rubber bushing equates that promptly rubber bushing is for waiting wall thickness structure.Can avoid the generation of rubber bushing slub heating failure conditions like this, but from being used for, when drilling pressure is excessive, deflection Deng the wall thickness rubber bushing is smaller, rotor blocks in stator easily, mud pressure is difficult for the destruction that discharge also can cause stator rubber, influences the operating efficiency and the useful life of screw drilling tool motor.
Summary of the invention
Technical problem to be solved by this invention is the deficiency at above-mentioned prior art existence, and the screw drilling tool motor stator of a kind of high efficiency and long service life is provided.
The present invention for the technical scheme that problem adopted of the above-mentioned proposition of solution is: comprise housing and rubber bushing, rubber bushing and housing endoporus are bonding, the rubber bushing endoporus is the continuous helical line style, radial section is circumferentially uniform petal-shaped, its difference be rubber bushing at the wall thickness of radial section for not waiting wall thickness, rubber bushing each petal on radial section is to its wall thickness of evagination highest point from the indent lowest part and increases progressively shape, and maximum ga(u)ge is 1.2~2 times of minimum thickness, and the shape of each petal is identical on the radial section.
Press such scheme, described rubber bushing each petal on radial section is the linear increment shape from indent lowest part to its wall thickness of evagination highest point, perhaps is the non-linear increasing shape.
Press such scheme, hole shape is identical with the shape of rubber bushing periphery in the described housing.
Press such scheme, described petal is 2~10.
Press such scheme, described rubber bushing each petal outer peripheral face on radial section is short secondary cycloid from the indent lowest part to the formed curve of evagination highest point, also can be other similarly smooth easement curves.
Beneficial effect of the present invention is: owing to vulcanized the abrasive rubber that one deck does not wait wall thickness on inner walls, form the rubber bushing that does not wait wall thickness, the evagination place wall thickness that the weakness of rubber bushing radius is a petal is thicker, can produce suitable strain, so both can avoid same wall-thickness stator when drilling pressure is excessive, rotor blocks in stator easily, mud pressure is not easy to discharge and the destruction of causing stator rubber, also avoided because the wall thickness variation of rubber bushing is big, heat accumulates in the thick part of rubber easily, make rubber swelling amount herein bigger, be easy to cause the problem of stator premature failure than other positions.Thereby it is less to reach rubber bushing swell increment difference when work is heated, and the motor stator efficiency improves greatly, and not easy to wear, and effectively prolonged useful life.
Description of drawings
Fig. 1 is the longitudinal section view of traditional screw drilling tool motor stator.
Fig. 2 is the longitudinal section view of existing pre-profile helicoid hydraulic motor stator.
The longitudinal section view of Fig. 3 one embodiment of the invention.
Fig. 4 is the A-A cutaway view of Fig. 3.
Embodiment
Further specify embodiments of the invention below in conjunction with accompanying drawing, comprise housing 1 and rubber bushing 2, rubber bushing is bonding through sulfidization molding and housing endoporus by abrasive rubber, rubber bushing endoporus 3 is the continuous helical line style, radial section is circumferentially uniform petal-shaped, described petal is 6, rubber bushing on radial section each petal (radius minimum place) its wall thickness is and increases progressively shape from indent lowest part (maximum radius) to the evagination highest point, be that wall thickness is thickeied gradually, and maximum ga(u)ge is 1.6 times of minimum thickness, rubber bushing each petal outer peripheral face 4 on radial section is short secondary cycloid from the indent lowest part to the formed curve of evagination highest point, the shape of each petal is identical on the radial section; Hole shape is identical with the shape of rubber bushing periphery in the housing.