CN201292766Y

CN201292766Y - Steel tooth roller bit

Info

Publication number: CN201292766Y
Application number: CNU2008201930277U
Authority: CN
Inventors: 蔡永忠
Original assignee: Kingdream PLC
Current assignee: Sinopec Oilfield Equipment Corp
Priority date: 2008-11-26
Filing date: 2008-11-26
Publication date: 2009-08-19
Anticipated expiration: 2018-11-26

Abstract

The utility model relates to a steel tooth cone bit which is used for drilling fields, such as petroleum, geology, and the like. The steel tooth cone bit comprises a tooth palm and a steel tooth cone, wherein the tooth palm is connected with the steel tooth cone by an axle neck arranged on the lower end of the tooth palm, and the periphery of the steel tooth cone is provided with teeth which are integrated with the tooth cone. The steel tooth cone bit is characterized in that when the teeth drill towards the steel tooth cone, the autorotation direction is deflective, and the cross sections of the teeth form an inequilateral trapezoid. The utility model has the advantages that firstly, because the shape of the cross section of the steel tooth cone is changed, under the condition that a tooth profile angle beta is not changed, the stress of tooth roots can be improved, consequently, the tooth intensity of the steel tooth cone is increased, and the break resisting performance can be strengthened; secondly, because front tooth angles of the teeth of the steel tooth cone are reduced, the sharpness and the earth layer drilling capability of the teeth are increased, the drilling and cutting performance of the tooth cone is further strengthened, the tooth cone bit can bear higher drilling pressure and rotating speed, and consequently, the rock breaking efficiency of the steel tooth cone bit is increased.

Description

A kind of steel tooth bit

Technical field

The utility model relates to a kind of steel tooth bit that is used for probing fields such as oil, geology.

Background technology

Rock bit mainly is made up of gear wheel and two parts of bit leg.Rock bit is divided into two kinds of steel tooth bit and insert bits usually, and steel tooth bit is also referred to as the mill teeth rock bit.The characteristics of steel tooth bit are that the tooth on the gear wheel is directly to form by processing on gear wheel, the cross sectional shape of tooth is isosceles trapezoid.For the abrasion resistance that strengthens steel-tooth cone can be applied weldering hard material wearing layer on the flank of tooth of tooth, to increase the drilling rate and the application life of steel tooth bit.

In drilling process, the tooth of steel-tooth cone can produce very high contact stress to the stratum and be used for fractured rock under the effect of the pressure of the drill, yet, under very high contact stress effect, tooth on the gear wheel also is easy to occur the situation of wearing and tearing even fracture in drilling process, especially under the situation that the stratum lithology changes, the pressure of the drill fluctuation can take place, cause tooth stressed irregular, cause tooth to rupture from tooth root.In addition,, mechanical separator speed and the pressure of the drill of rock bit are had higher requirement, and raising the pressure of the drill and rotating speed mean that teeth roots stress increases that the probability of tooth fracture increases along with the development of modern drilling technology.The tooth profile of tooth cross section of existing steel tooth bit is isosceles trapezoid, is symmetrical structure.The width that increases tooth root can strengthen the intensity of tooth tooth root, but this can make the tooth angle angle beta become big, influences the ability of tooth wedging bottom, thereby influences the raising of rock bit Drilling performance and bit speed.

Summary of the invention

Technical problem to be solved in the utility model is to provide a kind of steel-tooth cone teeth roots stress that can improve at the deficiency of above-mentioned prior art existence, to improve the steel tooth bit of rock bit Drilling performance.

The technical scheme that problem adopted that the utility model relates to solving above-mentioned proposition is: include bit leg and steel-tooth cone, bit leg links to each other with steel-tooth cone by the axle journal of its lower end, described steel-tooth cone periphery is laid with the tooth with the gear wheel one, its difference is the direction of rotation deflection of described tooth rotation when the drilling well of steel-tooth cone, and it is trapezoidal to make the cross section of tooth constitute inequilateral.

Press such scheme, the deflection of described tooth be the leading flank of tooth and trailing flank all to angle of steel-tooth cone direction of rotation deflection, make the cross section of tooth form that the leading flank limit is short, the inequilateral of the trailing flank length of side is trapezoidal.

Press such scheme, described deflection is the forward and backward side of tooth with respect to the tooth of the isosceles trapezoidal structure symmetry direction of rotation deflection to steel-tooth cone, and the angle [alpha] of deflection is 5 °～20 °.

Press such scheme, at the deposited weldering of the flank of tooth hard material wearing layer of described tooth.

Press such scheme, described steel tooth bit is two rock bit or tricone bit.

The beneficial effects of the utility model are: 1, the change by the steel-tooth cone shape of cross section, and under the constant condition of profile angle β, can improve the stress of tooth tooth root, thereby improve the tooth intensity of steel-tooth cone, strengthen the ability of its anti-fracture; 2, the tooth angle owing to the steel-tooth cone leading flank diminishes, the acuteness of tooth and the ability on wedging stratum have been improved, the Drilling cutting ability of gear wheel is further strengthened, also make rock bit can bear higher the pressure of the drill and rotating speed, thereby reach the efficiency of breaking rock that improves steel tooth bit.

Description of drawings

Fig. 1 is the overall structure stereogram of an embodiment of the utility model.

Fig. 2 is the partial sectional view of the single palm of roller bits part of the utility model.

Fig. 3 is the cross-sectional structure figure of isosceles trapezoidal structure symmetry tooth.

Fig. 4 is the fracture schematic diagram of tooth among Fig. 3.

Fig. 5 is the cross-sectional structure figure of tooth among embodiment of the utility model.

Fig. 6 applies the cross-sectional structure figure that has welded the hard material wearing layer for dental surface among embodiment of the utility model.

Fig. 7 is the cross-sectional structure figure of tooth among another embodiment of the utility model.

Fig. 8 is the cross-sectional structure figure of tooth among the 3rd embodiment of the utility model.

The specific embodiment

Further specify embodiment of the present utility model below in conjunction with accompanying drawing, be one or three gear wheel steel tooth bits, include three steel-tooth cones 2 and three bit legs 1, three bit leg tops are integrally welded, constitute bit body, bit leg links to each other with the steel-tooth cone cooperation by the axle journal 3 of its lower end, steel-tooth cone is the awl dentation, be laid with tooth 4 with the gear wheel one in the steel-tooth cone periphery, the direction of rotation deflection of described tooth rotation when the steel-tooth cone drilling well, be that the leading flank 7a of tooth and trailing flank 7b are all to angle of steel-tooth cone direction of rotation R deflection, make the cross section of tooth form leading flank limit weak point, the inequilateral of the trailing flank length of side is trapezoidal, before described deflection is tooth, trailing flank is with respect to the tooth of the isosceles trapezoidal structure symmetry direction of rotation deflection to steel-tooth cone, the angle [alpha] of deflection is 15 °, as shown in Figure 5, the profile angle β of tooth is 40 °～50 °, this moment, the angle of 6 of tooth leading flank 7a and tooth tops diminished, become big with the angle of tooth root 5, and the angle of tooth trailing flank 7b and gear tip clearance strengthens, diminish corresponding with the angle of tooth root 5; For strengthening the abrasion resistance of steel-tooth cone, can comprise on the flank of tooth of tooth that forward and backward side and tooth top 7, end face 8 apply weldering hard material wearing layer 9, as shown in Figure 6.The tooth of deflection can be part deflection or whole deflection on the steel-tooth cone.

Second embodiment of the present utility model as shown in Figure 7, the main difference part of it and a last embodiment is that the connection place of tooth leading flank 7a and tooth root 5 is a cambered surface, with the further stress state that improves the tooth tooth root.

The 3rd embodiment of the present utility model as shown in Figure 8, the main difference part of it and a last embodiment is that the tooth profile of tooth is the side direction arc, the leading flank 7a that is tooth is the cambered surface of indent, and trailing flank 7b is the cambered surface of evagination, and other is identical with first embodiment.Such profile of tooth can strengthen the scraping of steel-tooth cone and the performance on wedging stratum, and is convenient to taking out of of landwaste.

Claims

1, a kind of steel tooth bit, include bit leg and steel-tooth cone, bit leg links to each other with steel-tooth cone by the axle journal of its lower end, described steel-tooth cone periphery is laid with the tooth with the gear wheel one, it is characterized in that described tooth when the steel-tooth cone drilling well rotation the direction of rotation deflection, it is trapezoidal to make the cross section of tooth constitute inequilateral.

2, by the described steel tooth bit of claim 1, the deflection that it is characterized in that described tooth be the leading flank of tooth and trailing flank all to angle of steel-tooth cone direction of rotation deflection, make the cross section of tooth form that the leading flank limit is short, the inequilateral of the trailing flank length of side is trapezoidal.

3, by claim 1 or 2 described steel tooth bits, it is characterized in that described deflection is the forward and backward side of tooth with respect to the tooth of the isosceles trapezoidal structure symmetry direction of rotation deflection to steel-tooth cone, the angle [alpha] of deflection is 5 °～20 °.

4,, it is characterized in that the described flank of tooth at described tooth applies weldering hard material wearing layer by claim 1 or 2 described steel tooth bits.

5, by claim 1 or 2 described steel tooth bits, it is characterized in that described steel tooth bit is two rock bit or tricone bit.

6, by the described steel tooth bit of claim 3, the connection place that it is characterized in that described tooth leading flank and tooth root is a cambered surface.

7, by the described steel tooth bit of claim 3, it is characterized in that the tooth profile of tooth is the side direction arc, promptly the leading flank of tooth is the cambered surface of indent, and trailing flank is the cambered surface of evagination.

8,, it is characterized in that the tooth of deflection can be part deflection or whole deflection on the steel-tooth cone by the described steel tooth bit of claim 3.