CN202689941U

CN202689941U - Eccentric constant-width seal groove of cone bit

Info

Publication number: CN202689941U
Application number: CN 201220127145
Authority: CN
Inventors: 幸发芬
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-03-30
Filing date: 2012-03-30
Publication date: 2013-01-23
Anticipated expiration: 2022-03-30

Abstract

The utility model relates to an eccentric constant-width seal groove of a cone bit. The eccentric constant-width seal groove of the cone bit comprises a cone palm bearing, a cone inner hole, a seal groove and a seal piece. The seal groove arranged between the bottom of the cone palm bearing and an opening of the inner hole, a radial clearance A is arranged between a radial pressure-bearing cylinder of the cone palm bearing and a radial pressure-bearing cylinder of the cone inner hole, and a eccentricity C is arranged between a seal cylinder of the cone palm bearing and the radial pressure-bearing cylinder. The seal cylinder and the radial pressure-bearing cylinder have a diameter difference B which is equal to the radial clearance A, the eccentric direction is the same as the direction of stress to a cone, and the eccentricity C is half of the diameter difference, namely C = (1/2)A. Due to the design of the eccentricity and the diameter difference, the peripheral width of the seal groove and the peripheral compressibility of a seal ring of the seal groove cannot change because of the bearing clearance during operation of the cone bit, the width of the seal groove and the compressibility of the seal ring are stable, the compressibility of the elastic seal can be designed within a low range; and adaptability of the bearing seal to high rotational speed is improved, and the service life of the bearing seal ring is prolonged.

Description

The eccentric wide bearing seal groove of rock bit

Technical field

The utility model relates to the eccentric wide bearing seal groove of a kind of rock bit, is adapted to the closed type rock bit that oil, geology, engineering are used.

Background technology

The life-span of rock bit depends primarily on bearing.And the life-span of bearing depends primarily on sealing.The task one of sealing is to prevent that the lubricating grease in the bearing from leaking, the 2nd, and the mud that stops bit exterior to have corrosivity and abrasiveness is invaded bearing.In a single day sealing lost efficacy, and bearing will be worn soon, thereby caused drill bit to lose efficacy.

The sealing of rock bit generally all relies on the radial compression of elastic sealing elements to realize its sealing function.Such as patent US5524718, US5655611 employing is an O-ring seals, what patent US 3765495, US 4037673 adopted is a rectangular seal, what patent CN 201080787Y, US 6033117, US 6254275B1 adopted is Double seal ring, and what patent CN 2259868Y adopted is an X-shaped sealing ring.In these patents, potted component all is to realize its sealing function by radial compression.Be sealing device take mechanical seal as movable sealing although patent US4516641, US4666001, US4923020 adopt, they also contain the elasticity static seal element that pressure is provided to mechanical sealing surface.The radial compression that relies on these elasticity static seal elements too realizes the needs of its sealing and voltage supply.

Cone bit bearing radially is being gapped.The existence in these gaps causes elastic seal ring inconsistent in the compression ratio of circumferencial direction.When drill bit was worked, bearing was in stressed side contacts, and radial clearance all focuses on the non-stress side.So elastic seal ring reaches very big state in the compression ratio of stressed side, reach minimum state in the compression ratio of non-stress side.For leakage phenomenon does not occur in the sealing that guarantees the non-stress side, existing way is to strengthen the design compression ratio of elastic seal ring.

Drawback after the increasing compression ratio is obvious.Large compression ratio produces large frictional resistance and frictional heat, has reduced sealing ring and has adapted to high-revolving ability, has also shortened the application life of sealing ring.

The utility model content

The utility model by the off-centre of teeth palm bearing and the radial clearance between the bearing, and provides a kind of rock bit eccentric wide bearing seal groove for the deficiency in the above-mentioned bearing seal of rock bit.

The technical solution of the utility model is: comprise teeth palm bearing, gear wheel endoporus, seal groove and seal, its difference is that described seal groove is arranged between the aperture of teeth palm bearing bottom and gear wheel endoporus, and off-centre and the radial clearance between the bearing by teeth palm bearing form the wide of seal groove.

Press such scheme, comprise radially pressure-bearing cylinder and the O-ring cylinder that is positioned at its root on the described teeth palm bearing; Radially pressure-bearing cylinder and the O-ring cylinder that is positioned at its aperture are arranged on the described gear wheel endoporus; Described teeth palm bearing radially pressure-bearing cylinder and gear wheel internal orifice dimension has a radial clearance between the pressure-bearing cylinder; Described seal groove is arranged between the O-ring cylinder of the O-ring cylinder of teeth palm bearing bottom and gear wheel bore orifice; Between the radially pressure-bearing cylinder of described teeth palm bearing and the O-ring cylinder off-centre is arranged, eccentric direction is subjected to force direction identical with gear wheel, and eccentric size equals half of bearing radial gap value; The O-ring cylinder diameter of described teeth palm bearing is with radially the pressure-bearing cylinder diameter is variant, and difference value equals bearing radial gap.

The eccentric wide bearing seal groove of a kind of rock bit of the utility model advantage compared with prior art: adopt eccentric wide bearing seal groove, eliminated the seal groove width change that the existence because of the bearing clearance brings, realized the wait compression of bearing sealed ring at circumferencial direction, thereby reduced the designing requirement of bearing sealed ring compression ratio, improve sealing ring and adapted to high-revolving ability, prolonged sealing life.

Description of drawings

Fig. 1 is a kind of exemplary block diagram of the present utility model;

Fig. 2 is circumferencial direction schematic diagram of the present utility model;

Fig. 3 is the second exemplary block diagram of the present utility model;

Fig. 4 is the third exemplary block diagram of the present utility model;

Fig. 5 is the 4th kind of exemplary block diagram of the present utility model.

The specific embodiment

Fig. 1 is a kind of exemplary block diagram of the present utility model.Teeth palm bearing 1 cooperates with gear wheel endoporus 2, forms the bearing of rock bit.Teeth palm bearing comprises radially pressure-bearing cylinder 5 and O-ring cylinder 7.The gear wheel endoporus comprises radially pressure-bearing cylinder 6 and O-ring cylinder 8.Seal groove 3 is formed by teeth palm bearing O-ring cylinder and gear wheel endoporus sealing cylinder body.What seal groove 3 was in-built is an elastic seal ring 4.When rock bit is worked, stressed in stressed side F direction.Teeth palm bearing and gear wheel endoporus produce radial clearance A in the F side contacts at opposite side.

Bit leg seal

7 and 5 on bit leg pressure-bearing cylinder have eccentric C and the poor B of diameter.The poor B of diameter equals radial clearance A.Eccentric direction is identical with stressed direction.Eccentric big or small C equals half of the poor B of diameter.That is, A=B=2C.

Fig. 2 is circumferencial direction schematic diagram of the present utility model.The 11st, the projection of gear wheel endoporus O-ring cylinder 8.The 12nd, the projection of teeth palm bearing pressure-bearing cylinder 5.The 13rd, the projection of bit leg O-ring cylinder 7.The 14th, elastic seal ring.Because of the existence of eccentric C, when rock bit was worked, 11 and 13 was two concentric circles, and by 11 and 13 seal grooves that form, its width is constant at circumferencial direction.Sealing ring 14 compressed being installed in the seal groove, its compression ratio also is changeless.That is to say that the compression ratio of sealing ring is consistent in stressed side with the non-stress side.Need to not strengthen decrement for the minimum compression ratio that guarantees the non-stress side during design.Thereby the compression ratio of sealing ring can be designed in a lower scope.Lower compression ratio has improved sealing ring and has adapted to high-revolving ability, has prolonged the application life of sealing ring.

Fig. 3 is the second exemplary block diagram of the present utility model.Compare with the structure of Fig. 1, its difference is the teeth palm bearing sealing

The diameter of cylinder 7 is not the diameter greater than pressure-bearing cylinder 5, but less than the diameter of pressure-bearing cylinder 5, little value B also equals radial clearance A.

Fig. 4 is the third exemplary block diagram of the present utility model.With the difference of Fig. 1 be, seal is not single sealing ring, but mechanical sealing assembly 15.

Fig. 5 is the 4th kind of exemplary block diagram of the present utility model.With the difference of Fig. 1 be, seal is not single sealing ring, but the black box 16 that is formed by two sealing rings.

Claims

1. the eccentric wide bearing seal groove of a rock bit, comprise teeth palm bearing, gear wheel endoporus, seal groove and seal, it is characterized in that, described seal groove is arranged between the aperture of the bottom of teeth palm bearing and gear wheel endoporus, and off-centre and the radial clearance between the bearing by teeth palm bearing form the wide of seal groove.

2. the eccentric wide bearing seal groove of rock bit according to claim 1 is characterized in that, comprises radially pressure-bearing cylinder and the O-ring cylinder that is positioned at its root on the described teeth palm bearing.

3. the eccentric wide bearing seal groove of rock bit according to claim 1 is characterized in that, comprises radially pressure-bearing cylinder and the O-ring cylinder that is positioned at its aperture on the described gear wheel endoporus.

4. according to claim 2 or the eccentric wide bearing seal groove of 3 described rock bit, it is characterized in that, described teeth palm bearing radially pressure-bearing cylinder and gear wheel internal orifice dimension to a radial clearance (A) is arranged between the pressure-bearing cylinder.

5. the eccentric wide bearing seal groove of rock bit according to claim 1 is characterized in that, described seal groove is arranged between the O-ring cylinder of the O-ring cylinder of teeth palm bearing bottom and gear wheel bore orifice.

6. the eccentric wide bearing seal groove of rock bit according to claim 1 and 2, it is characterized in that, one off-centre (C) is arranged between the radially pressure-bearing cylinder of described teeth palm bearing and the O-ring cylinder, eccentric direction is subjected to force direction identical with gear wheel, eccentric size equals half of bearing radial gap value, i.e. C=(1/2) A.

7. the eccentric wide bearing seal groove of rock bit according to claim 6, it is characterized in that, the O-ring cylinder diameter of described teeth palm bearing and pressure-bearing cylinder diameter variant (B) radially, difference value (B) equals bearing radial gap (A), i.e. B=A.