US2259055A - Rotary machine - Google Patents

Description

Oct. 14, 1941. l-- E. ZERBE E AL 2,259.055 ROTARY MACHINE Filed Oct. 5, 1939 2 Sheets-Sheet 1 m A. y W W 5 W k y W 6 flfihll: Mn N Y... 6 M a H .U m nilmul M- 4/ J 1?? Z 2 J w 1% j i 4 Oct. 14, 1941. E. ZERBE ET AL ROTARY MACHINE 2 Sheets-Sheet 2 Filed 001;. 3, 1939 0 4 iii O ail UM) T011 Patented Oct. 14, 1941 ROTARY MACHINE Lewis E. Zerbe, Moneta, and Forrest J. Young, Los Angeles, Calif., assignors to The National Supply Company, Pittsburgh, Pa., a corporation of Pennsylvania Application October 3, 1939, Serial No, 297,688

12 Claims.

This invention relates to rotary drilling apparatus, and more particularly to an improvement in rotary machines as used in such apparatus for the drilling of wells. In the drilling of Wells, a rotary machine is employed, the primary function of which is to rotate the drill String so that the bit carried thereby will bore into the formation. In addition to this primary function, the rotary machine also performs secondary functions, among which are that of assisting in the operations of coupling and uncoupling the sections of drill string.

In the operation of uncoupling the drill string, the rotary machine is required to hold the lower section of the string stationary while the upper section is turnedv by means such as tongs to break the joint. When the joint is broken, the rotary machine is used for the purpose of turning the lower section of pipe while the upper section is held stationary until the unthreadin'g operation is completed. In the art this operation is known as breaking out. Similarly in the making up of a drill string, the rotary machine is required to hold the lower section of the drill string stationary while the upper section is threaded in or, as known in the art, spun in through suitable means such as by the use of a manila line, after which final tightening is eifected by use of tongs. This operation is known as making up. I v

s It will be apparent that during these two operations, means are required for maintaining the rotary machine stationary. Thus rotation locks are provided which may be selectively engaged to prevent rotation of the table in one direction while permitting rotation in the other direction.

. During the breaking out operation the rotation lock must selectively prevent counter-clockwise. rotation of the table While permitting clockwise. rotation.

In the making up operation, the rotation lock must act to selectively prevent clockwise rotation of the table. Ordinarily in rotary machines these requirements are provided through the use of a ratchet and pawl rotation look so that in the breaking out operation the ratchet and pawl prevents counter-clockwise rotation and in the making up operation the rotation lock prevents clockwise rotation.

The making up rotation lock is customarily formed as a ratchet and pawl because the ratchet action is necessary in case a drill string is employed which has left-hand threads. Such lefthand drill strings'are employed for fishing jobs or at other times where it is desired to rotate the drill string in a counter-clockwise direction.

In the conventional structure of rotary machine, ratchets are fixed upon the pinion shaft of the rotary machine and the ratchets are selectively engaged by separate pawl-s pivotally mounted upon the rotary-machine base; For example, such structure'is illustrated in the patent to Faulkner, No. 1,875,430. In this type of structure the shock loads occasioned in thefbreaking out and making up of the joints are transmitted through the gears of the rotary table to the rotation lock. These shock loads are sometimes of such magnitude as to cause distortion or failure of the gear teeth.

It is therefore an object of this invention to provide a rotation lock for break out and make up operations which will lock the table directly to the 'base to avoid the transmission of shockloads through the gears.

Another object of this invention is to provide a rotation lock for'a rotary machine which is so positioned as to engage the rotary table at its largest diameter.

Anotherobject of this invention is to provide a rotary table locking means including a locking pawl which may be raised vertically between guides on the rotary table base into locking position with respect to the rotary table.

Another object of this invention is to provide a lock pawl adapted to engage a lock element on the table of a rotary machine, the lock pawl being mounted for pivotal motion in a plane disposed substantially at right angles to the plane of rotation of thelock element.

Another object of this invention is to provide a rotary machine rotation lock including a lock pawl having such pivotal motion and in which locking pawl the center of gravity lies radially inward from the point of support so that the weight of the pawl acts to automatically move the pawl toward'locking position.

Another object of this invention is to provide a rotary table rotation lock which includes an overload releasing means.

Other objects and'advantages of this invention it is believed will be apparent from the following detailed description of a preferred embodiment thereof as illustrated in the accompanying drawings.

' In the drawings:

Figure 1 is a top plan view partly in horizontal section of the rotary machine embodying our invention.

Figure 2 is a side elevation of the rotary machine as illustrated in Figure 1 illustrating the make up rotation locking pawl in engaged position.

Figure 3 is a sectional elevation taken substantially on the line 3--3 of Figure 1 illustrating the make up rotation lock pawl out of engagement and in the position assumed when ratcheting.

Figure 4 is a fragmental sectional elevation taken substantially on the line 4-4 of Figure 1. Figure 5 is a fragmental sectional elevation taken substantially on the line 55 of Figure 4. Figure 6 is a fragmental plan principally in horizontal section of a modified form of rotary machine embodying our invention.

Figure 7 is a fragmental side elevation of the rotary machine as illustrated in Figure 6.

Figure 8 is a fragmental plan view of the structure illustrated in Figure 6 but illustrating the parts as moved to a different position.

Figure 9 is a fragmental elevation of the structure as illustrated in Figure 8.

In the preferred embodiment of our invention, particularly as illustrated in Figures 1 to 5, inclusive, the rotary machine is indicated as including a base I, supporting bearings 2, upon which the rotary table 3 is mounted for rotation. As is customary in such structures, an upthrust bearing 4 is provided for maintaining the table 3 in position.

A gear ring 5 is suitably secured to the table 3 in position to mesh with a pinion 6 mounted upon the pinion shaft 1. The pinion shaft 1 is rotatably supported on the base I. A drive sprocket 8 is secured to the shaft I.

In the form of rotary machine as illustrated, the base I is provided with an annular upstanding wall 9 which cooperates with the table 3 to form a labyrinth seal as indicated at III. The table 3 is provided with a depending flange II which overlaps the upstanding annular wall 9 in telescopic relation.

Disposed above and about the outer edge of the table 3 is a guard ring I2 which is supported in the base I on posts I3. Formed in the depending annular flange II are a series of lock recesses I4 which are adapted to receive the locking pawls I5' and IS. The pawls I5 and I6 are so constructed and mounted as to be of right and left-hand formation, that is, each functions to prevent rotation of the table 3 in the direction permitted by the other; except, however, in this factor, the pawls I5 and I3 are quite similar so that a detailed description of one serves as a description for the other. Accordingly, the pawl I5, which we will hereinafter refer to as the make up pawl has a body portion II which is adapted to lie flat against an abutment or stop shoulder I8 formed on the upstanding wall 9 of the base IL The pawl I5 hasa head portion I9 adapted to enter any one of the recesses I4. The body H of the pawl I5 is ofiset, as particularly illustrated in Figure 4 so that the lower end 20 is' spaced outwardly from the position of the head portion I9.

Means are provided whereby the vertical position of the pawl I5 may be determined so that in the lower position the head I9 does not reach high enough to engage within the recesses I4 and therefore the table 3 is free to rotate. Thus the lower end 20 of the pawl I5 fits within an opening 2I formed within the base I'. The opening 2I is a vertical opening and itsv side walls function as a guide for the end 20 of the pawl I5 during its vertical movement. In its lowermost position the pawl I5 is supported by its shoulder 22 engaging the upper end of the wall forming the guide opening 2|.

Means are provided for retaining the pawl I5 in its raised or operative position, which means is herein illustrated as including a latch member 23.

The make up pawl I5 is provided for holding the table 3 against clockwise rotation when the same is raised to the position where the head I9 engages within one of the recesses I4. In this position the latch 23 engages the upper surface cf the wall forming the guide hole 2I (Figure 5) maintaining the said pawl I5 in raised position.

In order to provide for the automatic engagement of this latch to retain the latch member 23 in latching position, the same is pivotally mounted on a pivot pin 24 within a latch recess 25 formed in the pawl I 5. The pin 24 is positioned in off-center relationship so that when free to do so, the latch member 23 swings outward into the latching position under the effect of gravity.

In order to provide for the convenient operation of the pawl I5, the lift lug 26 is formed thereon which the operator may grasp to raise the same vertically in the guide hole 2| to such position as to permit the latch member 23 to swing to latching position.

When in looking position, the make up pawl I5 has its abutment face 21 in engagement with the trailing wall 28 of one of the lock recesses I4.

In this position the main force is transmitted from the table 3 through the lock pawl I5 to the stop shoulder I8 formed on the base I, while the reaction force at the lower end of the pawl I5 a is also received by the base I.

Due to the offset construction of the body ll of the pawl I5, the center of gravity of the pawl lies radially inward from its point of support and therefore the weight of the pawl I5 acts to maintain the head portion I9 within the recess modate this rocking action, the lower end of the pawl I5 is provided with rounded surfaces 3i which fit within the walls of the opening 2I. Thus in Figure 3 the make up pawl I5 is indlcated tilted back from its locking position with its head portion I9 out of contact. Excessive over-travel is prevented by the head I9 engaging the depending annular flange 32 of the guard I2.

When the operator desires to return the pawl I5 to non-engaging position, it is only necessary for him to strike or kick the latch member 23 to release the same from engagement with the upper edge of the wall forming the receiving hole 2|, thereby letting the lock pawl I5 drop back into the opening 2 I.

The construction of the break out pawl I6 is entirely similar to that of the pawl I5 except that the surfaces 21 and 30 are in reversed position.

In the modified form of our invention as illustrated in Figures 6 to 9, inclusive, similar parts are indicated with the same numeral with the addition of an exponent a thereto. Thus in this modification of our invention, the table 3a. is mounted upon bearings 2a. supported by a base Ia. In this modification we have chosen to indicate only the make up pawl 15a, although it is obvious that a similar break out pawl will also be provided.

In the structureof make up pawl of this modification, the body portion Ila is provided with a head portion Him and the head portion is pivotally connected to the body portion on a pivot pin 33. Also in this modification the member |8a which forms the stop shoulder is a separate member mounted between fins 34 on the base la by means of the spaced bolts 35 and 36. Thus in this modification when th pawl la, is supported in looking position by means of the latch member 23a, the abutment face 21a. engages the trailing wall 28a of the recess Mapreventing clockwise rotation of the table 3a. However, should the table be rotated in a counterclockwise direction, the leading face 29a of the recess Ma strikes the tapered face 33a, of the head I9a of the pawl I50, causing the pawl l5a to ratchet back and forth, thereby permitting the said table 3a to rotate. If, however, an excessive load is applied to the abutment face 2111, the force transmitted by the head portion I90. to the abutment shoulder l8a is sufi'icient to shear the bolt 36 and move the abutment member lBa from the position indicated in Figure 6 to that indicated in Figure 8, and permitting the pawl head Isa to pivot about the pin 33 freeing the table 30. for rotation. The location of th bolts 35 and 36 is such that the bolt 35 receives the greatest proportion of the applied load and hence shears off before the bolt 35 is subjected to too great stress.

In this modification of our invention there is thus provided an over-load release which will effectively act to prevent breakage of the rotary machine parts. This becomes an important feature in the operation of such a rotary machine as it is obvious that th pawl I5a might be engaged by error while the table 3 is rotating. Such accidental engagement might result either through the error of the operator or by reason of one of the hoisting machines utilized in such drilling operations accidentally catching under the lifting lugs 2511. Also an excessive force might be applied to the table through the medium of the tongs (not shown) which are normally used to tighten the joints between the adjacent pipe sections. Through the medium of this over-load release excessive loading of the parts of the rotary machine is prevented. Excessive loading also does not unduly stress the pawl pivot 33 because the reaction force on the lower end of the head portion l9a. is transmitted through the back face of the head I90. directly to the guide wall 31a formed on the base la.

There is also provided a similar guide wall 31 for the pawl l5 as indicated in Figure 5.

Having fully described our invention, it is to be understood that we do not wish to be limited to the details herein set'forth, but our invention is of the full scope of the appended claims.

We claim:

1. In a rotary machine, the combination of a base, a table rotatably mounted on th base, a locking element carried on the table, a pawl supported on the base and adapted to engage said locking element to prevent rotation of the table in one direction, said pawl being adapted for pivotal movement in a plane positioned substantially at right angles to the plane of rotation of the locking element, and cooperating means on the table and the pawl adapted to cause the pawl to pivot away from the table upon rotation of the table in the other direction.

2. In a rotary machine, the combination of a stationary base member, a rotary member rotatably mounted on the base member, a lock element on said rotary member, a lock member supported on the base member and adapted to engage said lock element to prevent rotation of the rotary member in one direction, said lock member being adapted for pivotal movement in a plane disposed at an angle to the path of said lock element, and means including a bevel surface on said lock member adapted to be engaged by said lock element to impart pivotal movement to said lock member upon rotation of the rotary member in the other direction.

3. In a rotary machine, the combination of a base, a table mounted upon the base for rotation about a vertical axis, a lock element on said table, a lock pawl supported on the base and adapted for pivotal movement in a vertical plane, the lock pawl being adapted to engage the lock element to prevent rotation of the table, the center of gravity of the lock pawl being at one side of its pivotal axis whereby the weight of said lock pawl normally acts to maintain it in looking position.

4. In a rotary machine, the combination of a base, a table rotatably mounted on the base, a stationary annular guard supported on the base and having a depending skirt surrounding a portion of the table, a plurality of locking elements on the table within the depending skirt, a lock member supported on the base and adapted to extend within said depending skirt to engage said lock element, said lock member being adapted for pivotal movement in a plane disposed at an angle to the path of said lock elements, said pivotal movement being limited in one direction by engagement between the lock member and a lock element and limited in the other direction by contact between the lock member and the depending skirt of the annular guard.

5. In a rotary machine, the combination of a base, a table rotatably mounted on the base, a locking element carried on the table, a pawl supported by the base and adapted to be moved upward into the path of said locking element to prevent rotation of the table in one direction, latch means automatically acting to maintain said pawl in its upper position, said pawl and locking element being so proportioned that turning movement of the table in the other direction causes the'pawl to ratchet and allow the locking element to pass.

6. In a rotary machine, the combination of a base, a table rotatably mounted on the base, a locking element carried on the table, a pawl movable upwardly into engagement with said locking element, a latch pivotally mounted on said pawl, a shoulder on said base adjacent said latch, said latch being adapted to turn automatically about its pivot and engage said shoulder, upon the pawl being raised to its locking position, the engagement of said latch and shoulder acting to maintain the pawl in its raised position.

7. In a rotary machine, the combination of a base, a table rotatably mounted on the base, a locking element on the table, a pawl movable upwardly into engagement with said locking element, an opening in the base in which the lower end of the pawl is adapted to slide, a recess within the pawl near its lower end, a latch pivoted to said pawl and mounted within said recess, said latch being adapted to turn automatically about its pivot to engage an element of the base, upon the pawl being raised to its operative position, the engagement of the latch and base acting to maintain the pawl in its raised position.

8. In a rotary machine, the combination of a base, a table rotatably mounted on the base, a locking element carried on the table, a pawl comprising a head portion and a body portion pivotally connected, the pawl being adapted to be moved upwardly to a position in which the head portion engages the locking element to prevent rotation of the table, means including a frangible element adapted to maintain said head portion of the pawl in looking position, the frangible element being proportioned to withstand a normal load of predetermined magnitude but adapted to break in the event of an excessive load being transmitted by the locking element to said head portion, the breakage of the frangible element acting to allow the head portion of the pawl to pivot relative to the body portion and thereby allow the locking element to pass by.

9. In a rotary machine, the combination of a base, a table rotatably mounted on the base, a locking element carried on the, tablet, an abutment piece positioned on said base adjacent the path of said locking element, means including a frangible element adapted to secure the abutment piece upon the base, a pawl adapted to be operatively interposed between the locking element and the abutment piece to prevent rotation of the table, the frangible element being proportioned to withstand a normal load of predetermined magnitude but adapted to break in the event of an excessive load being transmitted by the table to the pawl, the abutment piece moving to an inoperative position upon breakage of the frangible element.

10. In a rotary machine, the combination of a'base, a table rotatably mounted on the base, a locking element carried on the table, an abutment piece positioned on said base adjacent the path of said locking element, means including a frangible element adapted to secure the abutment piece upon the base, a pawl comprising a head portion, and a body portion pivotally connected, said pawl being adapted to be moved upwardly to a position in which the head portion is operatively interposed between the locking element and the abutment piece to prevent rotation of the table, said frangible element being adapted to break in the event of an excessive load being transmitted by the table to the pawl, the abutment piece moving, to an inoperative position upon breakage of the frangible element whereby the head portion of the pawl may pivot relative to the body portion to allow the locking element to pass'by.

11. In a rotary machine, the combination of a stationary base member, a rotary member rotatably mounted on the base member, a lock element on said rotary member, stop means including a frangible element mounted on said base member adjacent the path of said lock element, a pawl adapted to be operatively interposed between the stop means and the lock element to prevent rotation of the rotary member, the frangible element being proportioned to withstand a normal load of predetermined magnitude but adapted to break in the event of an excessive load being transmitted by the lock element to the pawl.

12. In a rotary machine, the combination of a base having an upstanding wall, a table rotatably supported upon the base, a depending flange on the outer periphery of the table overlapping said upstanding wall in telescopic relation, a gear on said table within said upstanding wall, means carried by the base adapted to rotate said gear, a plurality of locking elements on said depending flange, and a lock pawl positioned outside said upstanding wall movable upwardly into the path of rotation of said locking elements.

LEWIS E. ZERBE. FORREST J. YOUNG.

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