US2660893A

US2660893A - Rod rotator for deep well pumps

Info

Publication number: US2660893A
Application number: US57787A
Authority: US
Inventors: John L Paterson
Original assignee: Willis Oil Tool Co
Current assignee: Willis Oil Tool Co
Priority date: 1948-11-01
Filing date: 1948-11-01
Publication date: 1953-12-01
Anticipated expiration: 1970-12-01

Description

Dec. 1, 1953 J. PATERSON ROD ROTATOR FOR DEEP WELL PUMPS 2 Sheets-Sheet 1 Filed Nov. 1, 1948 INVENTOR. JOHN J. Pare-230M IQTTOQNEY.

Dec. 1, 1953 J. PATERSON ROD ROTATOR FOR DEEP WELL PUMPS 2 Sheets-Sheet 2 Filed Nov. 1, 1948 lain/w I INVENTOR. zjhw 5. P4752501 BY 6D IQTTOENEY.

Patented Dec. 1, 1953 ROD ROTATOR FOB DEEP WELL PUMPS John L. Paterson, Long Beach, Calif., assignor to Willis Oil Tool Company, Long Beach, Calif a limited partnership Application November 1, 1948, Serial No. 57,787

19 Claims. 1

This invention relates to the oil well pumping art; more particularly, it relates to mechanism for rotating the rod string which actuates the p p- It is common to provide a string of rods, suspended adjacent their upper end from a vertically movable member, usually operated by a Walking beam, and extending downwardly through the well tubing, for attachment to the pump plunger, movement of the walking beam serving to reciprocate the plunger. In order to distribute wear on the pump plunger and barrel, and on the rod string and couplings due to contact with the well tubing, or to improve the operation of scrapers sometimes provided on the rods to remove deposits of paraifin or other residue from the inside of the tubing, mechanism is known which serves to rotate the rod string by small angular increments in accordance with its reciprocation.

It is an object of this invention to provide improved mechanism of this character.

It is another object of this invention to provide such mechanism which is adapted to advance the rod string by very small increments, so that the rotation may be for example at the rate of one revolution in 24 hours of operation.

It is another object of this invention to provide such mechanism which will not exert s'ufiicient torque to damage the rod string or other parts should the rod string develop excessive resistance to rotation, nor interfere with the operation of the walking beam.

It is another object of this invention to provide such mechanism which avoids a positive driving connection to the rod string, thus insuring against damage to the rod or tubing string or other parts in the event of freezing of the rod string or plunger.

In the prior art mechanism of this character, one way clutch means including a pawl and ratchet arrangement is often employed for rtating the rod string. Thus, the minimum angular advance is the angular extent of one ratchet tooth, which for purposes of design and mechanical strength cannot be reduced below a certain amount. To obviate this difficulty, a worm and gear mechanism is sometimes interposed between the ratchet wheel and the rod string, but this is an added complication and expense. It is another object of this invention to provide such mechanism having improved clutch means enabling advance of the rod string by minute angular increments, without the need of supplementary mechanism.

The one way clutch mechanism serves to connect an oscillatable member to angularly advance the rod string, said member being oscillated in response to the reciprocation of the rod string. It is another object of this invention to provide improved means for operating such oscillatable member.

It is another object of this invention to provide such operating means which is capable of adjustment to alter the angular movement of the oscillatable member by very small amounts and without altering the movement of the operating means.

This invention possesses many other advantages and has other objects which may be made more easily apparent from a consideration of one embodiment of the invention. For this purpose there is shown one form in the drawings accompanying and forming part of the present specification. This form will now be described in detail, illustrating the general principles of the invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

In the accompanying drawings:

Figure 1 is a side elevation showing a generally conventional operating connection between a rod string and a walking beam, incorporating the rod rotator of the invention;

Figure 2 is an elevation as seen from the right of Figure 1;

Figure 2a is a fragmentary section on an enlarged scale, taken substantially as indicated by line 2a-2a on Figure 1;

Figure 3 is a fragmentary elevation on an enlarged scale as seen from the left of Figure 1, showing the rod rotator;

Figure 4 is a detail transverse section, taken substantially as indicated by line 4-4 of Figure 3;

Figure 5 is a cross section, taken substantially as indicated by line 5-5 of Figure 3; and

Figure 6 is alongitudinal section taken substantially as indicated by line 6--6 of Figures-5 and 7; and

Figures 7 and 8 are cross sections taken substantially as indicated by the correspondingly numbered lines of Figure 6.

Referring to the drawings, the rod rotator is generally indicated by the numeral 5 and is shown as conventionally supported on a carrier bar 6 suspended by a cable loop 1 from a horse collar 8 at the end of the walking beam 9. The rod string I0 is supported on the rotator 5 by the aid of the rod clamp II, which is secured about the polished rod I2 and rests on the rotator 5. The walking beam 9 swings vertically about its trunnions I3, imparting reciprocating movement to the rod string II] in a well understood manner.

The rotator 5 comprises a body member I5 with upper and lower cylindrical portions I6 and Il coaxial with the polished rod I2 and having an intermediate bearing surface IS. The member I5 has a central bore !9 for freely accommodating the polished rod I2, the rod clamp II resting on the members upper face 20.

The means for rotatably supporting the body member I5 comprises a ring-like member 2| which rests on the carrier bar 6 and has a through bore 22 telescopically accommodating the lower cylindrical body portion IT. The upper face of the support member 2| provides an inner bearing surface 23, which cooperates with the bearing surface I8 to form a combined radial and thrust bearing structure 24 utilizing rolling bearing elements 25, which may conveniently be in the form of steel balls. Lubricant may be supplied to the .bearing structure 24 by the aid of va conventional grease fitting 26,

The support member 2| also provides an outer annular bearing surface 2'! rotatably supporting the operating member 28 which is of ring form and encircles the upper cylindrical body portion I6, being confined against the surface 2'? by a flange 29 on the body member I5. Lubricant may be supplied to the operating member 28 by the aid of the grease fitting 30. The parts are maintained in assembled relation by a spring ring 3! tightly embracing the lower cylindrical body portion I! and retained thereon by engagement with a shallow groove Il-b formed in the surface .I'I-a thereof, and accommodated in an annular clearance space 32 formed in the member 2| at the lower end of bore 22. Means are provided for ,causing the operating member 28 to oscillate about the body member I5, one way clutch means 33 being provided for coupling the members I5 and 28 so that such motion serves to advance the body member I5 about its axis by small angular increments.

This clutch means 33 is of generally conventional construction and is shown as comprising a plurality of wedge elements 34 in the form of steel balls disposed in angularly spaced relation 3 .in theoperating member 28 and. in contact with the surface IB-a of the cylindrical portion I 5. Each ball 34 is freely movable in a drilled hole 35 in the member 28, the hole being so positioned that its inner end portion cuts through the inner surface of the member 28. This allows the ball 34 to engage the cylindrical surface Iii-a as well as providing a surface inclined at a small angle .with respect thereto. The outer end of the hole 35 is closed by a threaded plug 36, a light compression spring 3! confined between the plug 33 and the ball 34 urging the ball to wedge between the surfaces.

It will be apparent from an inspection of Figure 7 that clockwise movement of the operating -member 28 as indicated by the full line arrow will cause the balls 34 to wedge tightly between these surfaces, so that body member I5 moves with the operating member 28, whereas counterclockwise movement of the operating member 28 as indicated by the dotted line arrow will move -,the balls 34 out of wedging relation, allowing the operating member 28 to move independently of the body member I5. The means for moving the .operating member 28 will be described. presently.

A one-way clutch arrangement 38, quite similar to the one-way clutch 33 just described, is provided between the support member 2| and the surface I'I-a of the lower cylindrical portion ll of the body member 6. Thus, as clearly shown in Figure 8, a plurality of balls 39 are accommodated respectively in bores 40 in the support member 2|, which are inclined toward the cylindrical surface Il-a, light compression springs 4| urging the balls into wedging relation as before.

It will be apparent that clockwise movement of the body member I5 urges the balls 39 out of wedging relation, so that the member I5 is free to turn in this direction. However, counterclockwise rotation of the member I5 causes the balls 35 to wedge and prevent such movement. By the provision of appropriately small clearances in the clutch means 33 and 38, advance of the member I5 by very small increments is possible.

The means for oscillating the operating member 28 will now be described (see Figures 3, 4 and 5). Thus, a lever arm is pivotally mounted on a pin 46 threaded into the supporting member 2| and has a pair of spaced abutment means 41 and 48 above the pin 45, between which a projection or driving lug 49 on the operating member 28 is accommodated. It will be apparent that as the arm 45 is rocked upwardly and downwardly about the pin 45, the

abutments

41 and 48 will alternately engage the lug 49 and move the operating member 28 clockwise and then counterclockwise with respect to the member 2.

If the spacing of the abutments 4? and 43 is greater than the diameter of the lug 49, arm 45 will have a certain amount of movement without causing movement of the operating member 28. Thus, the abutments 4i and 48 cooperate with lug 49 to form a lost motion connection between the arm 45 and the member 22, and by varying the spacing of the abutments 4?, 43, the amount of movement imparted to member 28 by a given movement of the arm 45 may be altered.

For this purpose, the abutment M is slidably mounted on the arm 45 as by being formed with a yoke 5| embracing the arm 45 and secured in adjusted position by a set screw 52. An adjusting screw 53 is interposed between the abutment 41 and a boss 54 fixed on the arm 45 to facilitate adjustment of the abutment 41.

The means for rocking the arm 45 comprises a rod 55, pivotally secured to the outer end of arm 45 by a universal joint 56 and extending upwardly to a connection 57 near the outer end of the walking beam 9. As best shown in Figure 2a, this connection comprises a ball 58 with a diametrical aperture through which rod is freely slidable, and having its upper and lower surfaces flattened to form seats for light compression springs 59 and 60, confined respectively by collars 6| and 62 adjustably secured on the rod 55. The ball member 58 is mounted for universal movement in a yoke 63 having a threaded stem 64 adjustably engaging a mounting bracket 65 secured adjacent the outer end.

The radius to the mountingbracket 55 being less than that to the point from which the rod string I0 is supported, as clearly shown in Figure l. The path of travel of the bracket 65 is shorter than that of the rod rotator 5. Thus, as the walking beam 9 swings downwardly from the midposition of Figure 1, arm 45 is rocked upwardly and when the walking beam swings upwardly from the mid-position, arm 45 is rocked downwardly. Since the motion of the walking beam is accuses transmitted to the rod 55, and thence to the rod rotator 5 by means of the

springs

59 and 60, damage to the mechanism in event the rod string should freeze or develop excessive resistance to rotation is prevented, the springs compressing sufifioiently to allow the walking beam to continue working without moving the rod 55. Further, since the body member 20 relies on the frictional contact thereof with the clamp II to impart rotation to the rod string, and as the clutch means frictionally drives the body member, it follows that in the event the rod string or the pump plunger freezes so that excessive resistance is ofiered to rotation, the clutch means or the body member or both will slip before causing damage to the parts.

From the foregoing it will be seen that a rod rotating mechanism has been provided wherein the movement of the member which angularly advances the rod string is capable of very close adjustment in a simple manner, and which in cludes a one-way clutch means capable of transmitting small angular increments of movement from said member to the rod string.

I claim:

1. A pump rod rotator comprising: a body member adapted to support a string of pump rods; means for rotatably supporting said member by a reciprocating portion of a well pumping equipment; an operating member supported by said means for rotary movement independently of said body member and coaxial therewith; means for imparting oscillating movement to said operating member; means coupling said members to move together in response to movement of said operating member in one direction whereby said operating member is efiective to advance said body member; said last named means decoupling said members upon reverse movement of said operating member; and means restraining reverse movement of said body member.

2. A pump rod rotator comprising: a body member adapted to support a string of pump rods; means for rotatably supporting said memher by a reciprocating portion of a well pumping equipment; an operating member supported for rotary movement independently of said body member and coaxial therewith; means for imparting oscillating movement to said operating member; means forming a one-way clutch for connecting said members for rotation together in one direction comprising spring pressed balls "carried by one member and a circular surface on the other member engageable by said balls; and cooperating elements for preventing reverse rotation of said body member comprising spring pressed balls and a circular surface engageable thereby; one of said elements being carried by said body members; the other element being carried by the said means rotatably supporting the body member.

3. A pump rod rotator comprising: a body member adapted to support a string of pump rods; means for rotatably supporting said member by a reciprocating portion of a well pumping equipment; an operating member supported for rotary movement independently of the body member and coaxial therewith; means for imparting oscillating movement to said operating member; one of said members having a surface circular about said axis; the other member having a surface inclined with respect to said circular sur face; and a wedge element confined between said surfaces and resiliently urged to wedging relation to cause rotary movement of one member in one direction to be imparted to the other member.

4. A pump rod rotator comprising: a body member adapted to support a string of pump rods; means for rotatably supporting said member by a reciprocating portion of a well pumping equipment; an operating member supported for rotary movement independently or" the body member and coaxial therewith; means for imparting oscillatory movement to said operating member; said members respectively having internal and external surfaces circular about said axis and in telescopic relation; and means carried by one of said members adapted to engage the surface of the other member to connect said members for rotary movement in one direction.

5. A pump rod rotator comprising: a body member adapted to support a string of pump rods; means for rotatably supporting said member by a reciprocating portion of a well pumping equipment; an operating member supported for rotary movement independently of the body member and coaxial therewith; means for im parting oscillatory movement to said operating member; said members respectively having internal and external surfaces circular about said axis and in telescopic relation; one of said members having a surface inclined with respect to said circular surfaces; and a wedge element confined between said inclined surface and the circular surface on the other member and resiliently urged to wedging relation between said surfaces to couple said members for rotary movement in one direction.

6. A pump rod rotator comprising: a body member having a surface for frictional contact with an element fixed to a string of pump rods and by means of which contact said string is supported on said member; a member for rotatably supporting said member by a reciprocating portion of a well pumping equipment; an operating member supported on one of said members for movement relative to said members about the axis of rotation of said body member; means including an element oscillatable in response to reciprocation of said pumping equipment portion for advancing said operating member; means form- 'ing a lost motion connection between said element and said operating member; means for adjusting said connection to vary the advance of said member with respect to the movement of said element; and means for coupling said members to move together in one direction.

'7. Apump rod rotator comprising: a body member adapted to support a string of pump rods; a member for rotatably supporting said body member; an operating element supported on one of said members for movement relative to said members about the axis of rotation of said body member; means including an osoillatable element; means forming a projection from one of said elements extending radially from the axis thereof; a pair of abutrnents forming a space on the other element positioned radially from the axis of said element and in which said projection is loosely confined whereby oscillation of said oscillatable element causes movement of said operating element about its axis; means for adjusting the spacing of said abutments to alter the amount of movement of said operating element with respect to the oscillatable element; and means forming a one-way clutch for coupling said body member and said operating element for rotation together in one direction.

'8. A pump rod rotator comprising: a body member adapted to support a string of pump rods and to be supported by a reciprocating portion of a well pumping equipment for rotation about the axis of said rod string; an operating member rotatable about said axis; an element oscillatable in response to reciprocation of said pumping equipment portion; means forming a lost motion connection between said element and said operating member whereby oscillatory movement of said element imparts oscillatory movement to said operating member; means for adjusting said connection to vary the movement of said operating member with respect to said element; and means forming a one-way clutch between said members comprising spring pressed wedge elements carried by one member and adapted to engage a circular surface on the other member.

9. A pump rod rotator comprising: a body member adapted to support a stringof pump rods; means for supporting said member by a reciprocating portion of a well pumping equipment for rotation about the axis of said rod string; an operating member rotatable about said axis; an element oscillatable in response to reciprocation of said pumping equipment portion; means forming a lost motion connection between said element and said operating member whereby oscillatory movement of said element imparts oscillatory movement to said operating member; means for adjusting said connection to vary the movement of said operating member with respect to said element; and means forming a pair of one way clutches respectively between said members and between said rotatable member and said support means to cause said rotatable member to advance with said operating member and to prevent reverse movement of said rotatable member; at least one of said clutches comprising spring pressed wedge elements engageable with a circular surface.

0. A pump rod rotator comprising: a body member adapted to support a string of pump rods; means for supporting said member for rotation about the axis of said rod string by a reciprocating portion of a Well pumping equipment; an operating member supported by said means for rotary movement about said axis and encircling said body member; means for imparting oscilla tory movement to said operating means; and means forming a one-way clutch between said members for imparting movement of said operating member in one direction to said body member.

11. A pump rod rotator comprising: a body member adapted to support a string of pump rods; said member having upper and lower circular portions and an intermediate downwardly directed thrust bearing surface; means adapted for support by a reciprocating portion of a well pumping equipment; said means having a bore telescopically accommodating the lower circular portion of said body member as well as an upwardly directed thrust bearing surface; said surfaces cooperating to rotatably support said body member; an operating member encircling the upper portion of the body member and rotatably supported on said support means; means for oscillating said operating member; and means respectively forming one-way clutches between said circular portions and said operating member and said support means to cause movement of said operating member inone direction to advance said body member and to prevent reverse movement of said body member.

12, In a pump rod rotator unit for application to a string of pump rods at a point between the pump rod clamp and the carrier bar for said string; a rotatable body member having a surface for frictionally drivingly contacting said clamp and supporting said string on said body member; a member connected with and supporting said body member for rotation relative thereto as well as relative to the string with said surface of the body member disposed for said contact with the clamp; said second mentioned member having a surface adapted to rest upon said bar operating means mounted on one of said members rotatable relative to both of said members; and means forming a one-way clutch between said operating means and said body member for rotating said body member.

13. In combination with a pump rod clamp and a carrier bar for a string of pump rods; a rotary body member having a surface on which said clamp is seated to support said string on said member for rotation therewith; a support member for said body member having a surface resting on said bar; a driving member for said body member mounted on one of said members for rotation relative to both of said members about the axis of said body member; means operable for rotating said driving member; and means forming a frictional drive between saio. said driving member and said body member.

14. A pump rod rotator unit for a reciprocable and rotatable string of pump rods; said string having a pair of elements thereon; one of said elements being fixed to said string; said rotator unit comprising; a rotary member; means adapted to be mounted between said elements for supporting said member for rotation about the axis of said string and in supporting and frictional driving contact with said fixed element; a rotatable operating member; and means forming a frictional drive connection between said members.

15. A pump rod rotator unit for a reciprocable and rotatable string of pump rods; said string having a pair of elements thereon; one of said elements being fixed to said string; said rotator unit comprising; a rotary member; means adapted to be mounted between said elements for supporting said member for rotation about the axis of said string and in supporting and frictional driving contact with said fixed element; an operating member movable for turning said rotary member; means forming a frictional drive connection between said operating member and said rotary member, an osoillatable member; and means forming a lost motion connection between said osoillatable member and said operating member.'

16. A pump rod rotator unit for a reciprocable and rotatable string of pump rods; said string having a pair of elements thereon; one of said elements being fixed to said string; said rotator unit comprising; a rotary member; a member adapted to be mounted between said elements for supporting said rotary member for rotation about the axis of said string and in supporting and frictional driving contact with said fixed element; an operating member supported on one of said members for rotation relative to said members about the axis of said rotary member; means forming a drive connection between said operating member and said rotary member; an oscillatable member, means forming a lost motion connection between said oscillatabie member and said operating member; and means for adjusting said lost motion connection to vary the response of said operating member to said oscillata-ble member.

17. A pump rod rotator unit for a reciprocable and rotatable string or pump rods; said string havinga pair of elements thereon; one of said elements being fixed to said string; said rotator unit comprising; a rotary member; a member adapted to be mounted between elements for supporting said rotary member for rotation about the axis of said string and in supporting and frictional driving contact with said fixed element; said members having opposed portions, an operating member movable relative to and disposed between said opposed portions for turning said rotary member; a projection on said operating member: means forming a drive connection between said operating member and said rotary member; an oscillatable element; supporting means for said oscillatable element; and a pair of abutments on said oscillatable element for alternately contacting said projection and turning said operating member on oscillation of said oscillatable element.

18. A pump rod rotator unit for a reciprocable and rotatable string of pump rods; said string having a pair of elements thereon; one of said elements being fixed to said string; said rotator unit comprising; a rotary member; a member adapted to be mounted between said elements for supporting said member for rotation about the axis of said string and in supporting and frictional driving contact with said fixed element; one of said members having a circumferential recess; an operating member movable in said recess for turning said rotary member; a projection on said operating member; means forming a drive connection between said operating member and said rotary member; an oscillatable element; supporting means for said oscillatable element;

a pair of abutments on said oscillatable element for alternately contacting said projection and turning said operating member on oscillation of said oscillatable element; and means for adjusting one of said abutments to vary response of said operating member to the oscillatable element.

19. In combination with a string of pump rods having a carrier bar and a clamp thereon; the latter being fixed to the string; a rotary member having a surface on which said clamp is seated to support and frictionally drive said string; a member mounted between said rotary member and said carrier bar supporting said rotary member for rotation about the axis of said string; a drivin element supported on one of said members for movement relative to said members about the axis of said rotary member, means on one of said members restraining axial movement of said driving element; and means forming a frictional drive connection between said driving element and said rotary member.

JOHN L. PATERSON.

References Cited'in the file of this patent UNITED STATES PATENTS Number Name Date 529,322 Edwards Nov. 13, 1894 529,323 Edwards Nov. 13, 1894 792,567 Wright June 13, 1905 1,228,673 Hriber June 5, 1917 1,574,518 Sargent Feb. 23, 1926 1,633,013 Gluyas June 21, 1927 1,644,913 Burgess Oct. 11, 1927 FOREIGN PATENTS Number Country Date 265,179 Great Britain Jan. 17, 1927