US2046956A

US2046956A - Inclination indicating device

Info

Publication number: US2046956A
Application number: US612002A
Authority: US
Inventors: Theodore L Lynch; Harry L Rilling
Original assignee: WARREN MACCLATCHIE J
Current assignee: J WARREN MACCLATCHIE; WARREN MACCLATCHIE J
Priority date: 1932-05-18
Filing date: 1932-05-18
Publication date: 1936-07-07
Anticipated expiration: 1953-07-07

Description

July 7, 1936.

T. L. LYNCH ET AL INCLINATION INDICATING DEVICE Filed May '18, 1932 2 Sheets-Sheet l F'IE- Z- INVENTORS THEODOEE L. LYNCH HAQQY L. QILLINGY Ar'T ORNEY July 7, 1936.

2 Sheets-Sheet 2 Filed May 18, 1952 FIE. E1-

95 II/ IVIAI'II/l/l/II INVENTOPS THEODORE L. LYNCH BY HAPPY L. PILL/Ne 7 73 ATTORNEY i wma Patented July 7, 1936 2,046,956 INCLINATION INDICATING DEVICE Theodore L. Lynch, Sonthgate, and Harry L. Billing, Bellflower, Calif.; said Billing assignor to J. Warren MacClatchie, Compton,

CaliL,

doing business as MacClatchic Manufacturing Company Application May 18 1932, Serial No. 612,002

25 Claims.

This invention has to do in a general way with devices for indicating inclination, and is more particularly related to improvements in inclination indicating devices for oil wells of the type shown in our Patent No. 1,854,208, issued on April 19, 1932.

The device contemplated by this invention like that disclosed in our patent above identified has as its primary object the production of means embodied in the drill pipe for obtaining a sensible indication of inclination through the medium of the drilling fluid.

It is a fundamental object of the present invention to produce a device of the class described which embodies a valve situated in the path of the circulating fluid, such valve being associated with gravity actuated means and arranged so as to be operated at the option of the driller. In the operation of the device contemplated by our.

present invention, the' gravity actuated means does not operate the valve as in the device shown in our former patent, but is arranged so that the valve is either closed or opened by the pressure of the drilling fluid, depending upon the verticality of the pipe. If the valve is closed, the resultant restriction causes an increase in pressure which can be observed on asuitable gauge provided in the fluid circulating system or which,

in the event the valve is constructed so as to completely close the passage through the pipe, the increase in pressure will be suilicient to stop the operation of the pump.

It is a further object of our invention to produce a device of the class described which may be set or adjusted so that a sensible indication is obtained when the instrument is inclined beyond a predetermined angle. For example, the device may be set so as to give an indication when the drill pipe is inclined beyond say 2 with the vertical, an inclinationless than this giving no indication.

It is a further object of this invention to produce a device of the class described wherein the operation is controlled solely through the medium of the fluid circulating pump, and which does not necessitate disturbing the drill pipe.

The general construction of the device contemplated by this invention comprises a suitable barrel or pipe section adapted to be interposed in the drill pipe, such barrel containing a valve seat. A valve stem is suitably mounted in the barrel for reciprocation therein and this stem carries a valve adapted to engage the valve seat. The lower end of the valve stem is provided with a 55 pendulum mounted for universal movement and adapted to engage a suitable pendulum re'st which is mounted in the barrel .therebelow. The pendulum rest is so constructed and so positioned as to be engaged by the tip of the pendulum within predetermined limits in the inclination of the 5 pipe and is thereby effective to hold the valve against movement relative to the valve seat in the event the pendulum engages the seat or to permit the movement of the valve relative to the seat in the event the pendulum clears the pendulum rest. 10

The device may be constructed so that the valve is closed by the action of a pressure fluid in the event the pipe is inclined and is held open by the pendulum in the event the pipe is vertical; or it maybe constructed so that the valve is held in 15 a closed position by the pendulum in the event the pipe is inclined and is opened by the action of the pressure fluid in the event the pipe is vertical.

It is a further object of this invention to produce a device of the class described in which the valve is hydrostatically balanced in the pressure fluid contained in the pipe, such valve being associated with yieldable means to open the same or to move the valve away from the seat when the pump is stopped.

It is a further feature of a modified form of I our invention that the device is provided with a so-called float valve which may be used to float the drill pipe into the well and which also acts as a blow-out preventer.

It is a further feature of this invention that the device is of simple form and construction; is not liable to excessive wear; and may be economically manufactured.

The details in the construction of a preferred embodiment of our invention. together with other objects attending its production, will be best understood from the following description of the accompanying drawings which are chosen for illustrative purposes only, and in which- Fig. 1 is a broken elevation with parts in section showing an oil well drilling apparatus and illustrating the manner in which our invention is used in connection therewith;

Fig. 2 is a sectional elevation illustrating the details in the construction ofa preferred form of our invention;

Fig. 3 is a plan section taken in a plane represented by the line 3-3 of Fig. 2; r

Fig. 4 is a sectional elevation of a modified form of our invention;

Fig. 5 is a plan section taken in a plane represented by the line 5-5 in Fig. 4; and

, Fig. 6 is a sectional elevation of another modifled form of our invention.

More particularly describing the invention as herein illustrated, reference numeral H indicates a drill pipe which is shown as extending into a bore hole l2, and has a drill bit l3 provided on its lower end. The drill bit [3 is shown as being mounted in the lower end portion of a barrel l4 which forms a part of the drill pipe and which .contains the inclination indicating device contemplated by this invention.

The upper end portion of the drill pipe H is provided with a Kelly l5 of the usual construction which extends through a rotary table I6, and has mounted on its upper end a head 11 through which a drilling fluid, such as rotarymud, is adapted to be pumped into the drill pipe under pressure from a conduit system indicated by reference numerals I8 and I9. The drilling fluid is forced into the conduit system under pressure by any suitable means such as the pump 20. Reference numeral 2| indicates a pressure gauge which may be provided in the conduit system at any suitable point for the purpose of indicating an increase in pressure in such fluid during the operation of the inclination indicating device.

The details in the construction of a preferred form of our invention are best illustrated in Figs. 2 and 3 where the barrel I4 is shown as being threaded at its two ends as indicated by

reference numerals

25 and 25 for interposition in a drill pipe or the like. Reference numeral 21 indicates a shoulder which is formed in the passage through the barrel and is adapted to carry a supporting ring 28. Reference numeral 28' indicates a valveseat ring which rests upon the upper edge of the supporting ring 28 and is shown as being provided with an annular valve seat 29. In order to reduce the liability of wear upon the valve: seat, due to the abrasive action of the circulating fluid, we propose to make the seat ring 28 in the form of an internally reinforced rubber ring, the reinforcement being indicated by reference numeral 30, and the rubber by reference numeral 3L Reference numeral 32 indicates a clamping ring which is in threaded engagement with the threads 25 and is adapted to clamp the rings 28 and 28' against the shoulder 21. The supporting ring 28 is formed with a spider 33 which has a central portion 34 spaced inwardly from the inner surface of the ring 28, such central portion having a downwardly extending threaded projection 35 and being provided with a central passage 36 carrying a packing gland 31 through which a valve stem 38 slidably extends. The upper end portion of the valve stem 38 is provided with a valve 39 which is adapted to be moved downwardly into engagement with the valve seat 29 by the pressure of the circulating fluid when the pump 20 is'operated. The lower end of the valve stem is provided with a universal joint 40 whereby a pendulum 4| is suspended for universal movement.

In this form of our invention the downwardly extending projection 35 is in threaded engagement with a case 44, such case having a spider plug mountedin its lower end and having an inwardly extending'flange 46 formed at an intermediate point thereon. The flange 46 carries a 'yieldable member in the form of a coil spring 41,

the upper end of which engages a washer 48 which is fixed to the valve stem 38. f This washer is normally heldin spaced relation with the bottom of projection 35 by a plurality of downwardly extending projections or bosses 50. In this manner the washer is completely surrounded by a fluid contained within the case 44 so that the valve and its associated parts are hydrostatically balanced when there is no flow of fluid through the pipe, as will be hereinafter more fully explained. The bottom plug 45 is provided with an internally threaded recess 52 which is adapted to receive a pendulum rest 53. The case 44 serves to protect the pendulum and its associated parts from the action of the drilling fluid.

In the operation of the device, it will be understood that the drill pipe is filled with a fluid, such as the rotary mud, and it is important that the valve be hydrostatically balanced when there is no flow of fluid through the pipe so that the spring 41 may be effective to maintain the valve in a normal upward position regardless of the depth to which the instrument is lowered into the well. For accomplishing this, we propose to fill the case 44 with a liquid such as oil, and to provide a pair of oppositely operated

check valves

55 and 56 in the lower end portion of the case. In this manner we balance the pressure on the area of the valve stem at the top of the valve 39 with a corresponding pressure on a corresponding area on the pendulum.

It will be seen, therefore, from the construction so far described, that when the pump is not operating, there being no flow of fluid through the pipe and the barrel and no differential pressure above the valve, the valve 39 will be forced to the position shown in Fig.2 by the action of the coil spring 41. When the pump is started the differential pressure between the region above and below the valve will cause the valve to move downwardly, and in the event the barrel is vertical such downward movement forces the tip 58 of the pendulum into the position A whereit engages the upper surface of the pendulum rest 53, the valve 38 being moved to the position A. In the event the pipe is tilted at an angle with the vertical, the angle being such that the tip of the pendulum clears the pendulum rest, the pendulum is forced into position '3 of Fig. 2, and the valve 39 moves to the position B where it rests upon the valve seat 29. When the valve is in the position A, it will be observed that the area of the annular opening surrounding the valve has not changed materially from the area of the annular opening which surrounds the valve when it is in the full line or neutral position. There will, therefore, be no sensible indication of an increase in pressure at the surface of the ground when the valve moves into this position. When the valve is forced to the position B, however, the passage through the drill pipe is completely restricted and there will be an immediate increase in pressure observed on the gauge 2|, such increase in pressure being suflicient to stop or stall the pump 20 in the event the operator doesv not stop the pump as as soon as the increase in pressure is observed.

In order that there may be a direct axial thrust through the pendulum and the universal joint 40 when the tip of the pendulum engages the pendulum rest, we provide the pendulum rest with an upper concave surface, and point the tip of the pendulum 550 that the pendulum is always 'centeredonthe' rest regardless of the point at which it makes contact.

It was pointed out as onejof the objects of this inventionto produce a de'vice of the" class described which can be adjusted so as to operate when the drill stem is inclined beyond various predetermined angles. This adjustment is accomplished by using pendulum rests of various diameters, since the inclination at which the valve is closed depends entirely upon the extent to which the pendulum may swing before it clears the pendulum rest. Means are preferably provided whereby the pendulum is definitely engaged by its rest as long as the inclination is within the predetermined limits at which the device is intended to remain inoperative, and just as definitely clears the rest to permit operation of the device as soon as the inclination exceeds said predetermined limits. For this purpose the rest 53 is arranged so that when the inclination is just at said predetermined limits, the pointed tip of the pendulum does not engage a flat abutment surface of the rest such as might cause the pendulum to hang up, but engages a part of the rest which provides merely a line contact whereby the pendulum is prevented from hanging up but must either swing outwardly beyond said line for completely clearing the rest and permitting operation of the device, or is definitely confined within the predetermined limits so as to prevent operation of the device. As an instance of such line contact the upper concave surface of the rest may be continued all the way to the outer side surface ofthe rest so as to meet said side surface at less than a rightangle and so as to form an abutment edge I53 which provides merely a line contact and not a plane surface contact. Consequently if the inclination is such that the pointed tip of the pendulum engages exactly on the edge I53 it must immediately slide off to one side or the other, depending upon whether the inclination is just within or just beyond the predetermined limits.

In using the device, a pendulum rest, which will be cleared by the pendulum when the required permissible inclination in the bore hole is exceeded, is first mounted in the base plug 45, and the barrel with the drill pipe and Kelly is mounted on the bit l3. The drilling operation is then started in the usual manner and verticality indications may be obtained at any desired intervals of depth as the hole progresses.

The procedure of obtaining an inclination .or verticality indication consists in first stopping the operation of the pump, after which the valve is automatically lifted to the full line position shown in Fig. 2. The operation of the pump is then started and if no appreciable increase in pressure is observed, the driller knows that the bore hole has not deviated beyond the inclination permitted by the size of the pendulum rest. If, however, a marked increase in pressure is observed, the driller knows thatthe bore hole has deviated to such an extent that the pendulum has cleared the pendulum rest, which is greater than the permissible inclination, and the drill pipe must be lifted to the point at which the last reading was taken, when the necessary steps are taken to straighten the course of the bore hole. It is advisable to stop the rotation of the drill pipe during the brief interval necessary for stopping and starting thepump.

In order to avoid the possibility of rotary mud, sediment, and the like, accumulating about the extending end portion of the valve stem, we pro-.

vide a rubber sleeve 60 which extends from the upper portion of the packing gland 38 to the upper end of the valve stem. Also, in order to avoid cutting action on the sleeve and its associated parts, we provide the valve with a downwardly extending skirt 6|.

The modified form of our invention shown in Fig. 4, is similar in construction and operation to the form shown in Fig. 2, and the various parts thereof corresponding to the parts in Fig. 2, are indicated by the same reference numerals distinguished by the prime mark.

The chief feature of this modified form of our invention resides in the provision of a float valve 89 which is slidably mounted on the valve stem 38' and is adapted to engage a-seat 66 which is I formed on the underside of the seat ring 61. The float valve 69 is normally forced upwardly toward the seat 66 by a coil spring 68 and is adapted to be moved downwardly from the seat by the action of pressure fluid passing through the drill pipe or conduit. The valve 69 is provided with a skirt which corresponds in function to the skirt 8| on the valve 38 in Fig. 2, and the valve stem 38' may be provided with a sleeve 60 which has the same function as the sleeve 68 of Fig. 2. The upper end portion of the valve stem 38' is provided with a valve 39', and in this form of our invention we provide the valve with notches 18 which prevent the complete restriction of the passage through the barrel when the valve is closed. The notches, however, do not prevent suflicient restriction to obtain an appreciable increase in pressure in the pumping or pressure fluid which may be observed on the gauge 2|.

The float valve 89 is adapted for use in districts where the drill pipe is floated into the well, and also acts as a blowout preventer since this valve will be automatically closed in the event the pressure in the well below the valve is greater than the pressure of the pumped fluid above the valve. Such an increase in pressure frequently occurs when the drill bit enters regions of high gas pressure.

The modified form of our invention, shown in Fig. 6, is similar in principle of operation to the form described in connection'with Figs. 2 and 4. In this device, however, thevalve is normally maintained in a closed position, and is held in a closed position by the pendulum in the event the drill pipe is inclined beyond a predetermined angle with the vertical. vWhen the drill pipe is vertical the valve is adapted to be opened by the pressure fluid. The observed results are, however, the same as the observed results in the other forms since there is no observed increase in pres; sure when the drill pipe is vertical as contrasted with a marked increase of pressure when the drill pipe is inclined from the vertical.

In this form of our invention, reference numeral 15 indicates a barrel which is provided with an inner shoulder 16 adapted to carry a supporting ring 11. The upper edge of the supporting ring 11 is engaged by a seat ring 18 which in turn is shown as being in threaded engagement with the threads 19 in the upper end portion of the barrel.

Reference numeral indicates a valve adapted to seat against the lower face of the valve seat 8', such valve being mounted on'the upper end of a valve stem 82 which extends downwardly through a passage 83 in a spider member 84 formed or mounted in the supporting ring 11. The lower end of the valve stem carries a universal joint 86 which in turn supports a pendulum 81. The lower end of the pendulum terminates in a tip member 88 which is positioned in close proximity to a concave pendulum rest' 89.

i pendulum when the drill pipe is vertical or is upon the area of the opening.

When the drill pipe is vertical or is inclined, as pointed out above, the valve is moved downwardly against the action of the spring 41a bythe action of the pressure fluid into the dot and dash line position C. When the drill pipe is inclined beyond the predetermined limits mentioned above, the tip of the pendulum engages the surface of the pendulum rest and the valve is held closed, the resultant restriction in the passage through the drill pipe causing a sensible increase {in pressure at the surface of the ground.

Reference numerals 98 and 99 indicate screens which are positioned on opposite sides of the operating mechanism in order to prevent the admission of sand and other abrasive material into such mechanism.

It will be apparent from-the foregoing description that the device contemplated by this invention, is of simple form and construction, and that it is automatically operable to give a sensible indication of inclination at the surface of the ground without the drilling equipment except to stop the rotation of the drill pipe and stop and start the pump.

It is to be understood that, while we have herein described and illustrated certain preferred forms of our invention, the invention is not limited to the precise construction described above, but includes within its scope whatever changes fairly come within the spirit of the appended claims.

We claim as our invention:

1. In combination with a drill pipe and a fluid pressure system for forcing a fluid therethrough, means for indicating whether or not said pipe is vertical by a pressure change in said fluid pressure embodying: a valve stem reciprocably mounted in said drill pipe; a valve on said valve stem adapted to be moved downwardly by the pressure of said fluid; a seat for said valve; a pendulum on the lower end of said valvestem; and a pendulum rest below said pendulum, said rest being formed so as to be engaged by said pendulum when said pipe is inclined from the vertical beyond a predetermined minimum and thereby hold said valve against movement relative to said seat.

2. In combination with a drill pipe and a fluid pressure system for, forcing a fluid therethrough, means for indicating whether or not said pipe is vertical by a pressure change in said fluid embodying: a valve seat in said pipe; a valve associated with said seat for restricting the flow of fluid through said pipe; and gravity actuated means associated with said valve and adapted to hold said valve against movement relative to said seat when said pipe is inclined from the vertical beyond a predetermined minimum.

3. In combination with a drill pipe and a fluid pressure system for forcing a fluid therethrough, means forindicating whether or not said pipe is vertical by a change in said fluid pressure embodying: a valve seat in said pipe; a valve above inclined within predetermined limits, depending said seat adapted to be forced into engagement with said seat by said pressure fluid; a valve stem secured to said valve; means for slidably supporting said valve stem; yieldable means associated with said valve stem for normally forcing said valve away from said seat; a pendulum on the lower end of said valve stem; a rest of predetermined area mounted in said pipe below said pendulum and adapted to be engaged by the lower end of said pendulum thereby holding said valve away from said seat when said pipe is vertical, and a second valve slidably mounted on said valve stem below said seat and adapted for seating engagement therewith for floating the pipe into a well.

4. In combination with a drill pipe and a fluid pressure system for forcing fluid therethrough, means for indicating whether or not said pipe is vertical by a change in fluid pressure embodying: a valve seat; a valve below said seat; a stem secured to said valve and extending downwardly therefrom; yieldable means for normally forcing said valve into engagement with said seat; a pendulum on the lower end of said stem; and a pendulum rest mounted in said pipe below said pendulum and adapted to be engaged by said pendulum and thereby hold said valve against move- 5. In combination with a drill pipe and a fluid pressure system for forcing fluid therethrough, means for indicating whether or not said pipe is vertical by a change in fluid pressure embodying: a valve seat; a valve below said seat; a stem secured to said valve and extending downwardly therefrom; yieldable means for normally forcing said valve into engagement with said seat; a pendulum on the lower end of said stem; and a pendulum rest mounted in said pipe below said pendulum and adapted to be engaged by said pendulum and thereby hold said valve against movement away from said seat by the action of a pressure fluid when said pipe is inclined from the vertical, said rest being provided with an opening of predetermined area to receive the lower end of said pendulum when said drill pipe is vertical thereby permitting the movement of said valve away from said seat by the pressure of said fluid.

6. In combination with a drill pipe and a fluid pressure system for forcing a fluid therethrough, means for indicating whether or not said pipe is vertical by a change in said fluid pressure embodying: a valve seat in said pipe; a valve above said seat adapted to be forced into engagement with said seat by said pressure fluid; avalve stem secured to said valve and extending downwardly therefrom; means for slldably supporting said valve stem; yieldable means associated with said valve for normally forcing said valve away from said seat; a pendulum on the lower end of said valve stem; a rest of predetermined area mounted in said pipe below said pendulum and adapted to be engaged by the lower end of said pendulum thereby holding said valve away from said seat when said pipe is vertical; 8. second valve slidably mounted on said valve stem below said seat; and yieldable means for forcing said second valve toward said seat.

7. For use in combination with a pipe and a fluid pressure system for forcing fluid therethrough, means for indicating whether or not said pipe is vertical by a change in fluid pressure embodying a barrel adapted to be mounted in said pipe; a valve seat in said barrel; a spider in said barrel below said seat; a valve stem slidably mounted in said spider; a valve on said stem adapted to be forced into engagement with said seat for-restricting the flow of fluid from said pipe through said barrel; a pendulum on the lower end of said stem; a pendulum rest mounted in said barrel below the point of suspension of said pendulum and adapted to be engaged by the tip of said pendulum for holding said valve away from said seat against the action of a pressure fluid, and a second valve slidably mounted on said valve stem below said seat and adapted for seating engagement therewith for floating the pipe into a well.

8. For use in combination with a pipe and a fluid pressure system for forcing fluid there'- through, means for indicating whether or not said pipe is vertical by a-change in fluid pressure embodying: a barrel adapted to be mounted in said pipe; a valve seat in said barrel; a spider in said barrel below said seat; a valve stem slidably mounted in said spider; a valve on said stem adapted to be forced into engagement with said seat for restricting the flow of fluid from said pipe through said barrel; a pendulum on the lower end of said stem; a pendulum rest mounted in said barrel below the point of suspension of said pendulum and adapted to be engaged by the tip of said pendulum for holding said valve away from said seat against the action of a pressure fluid, said pendulum rest being of smaller diameter than the distance through which the tip of the pendulum may swing, and a second valve slidably mounted on said valve stem below said seat and adapted for seating engagement therewith for floating the pipe into a well.

'9. For use in combination with a pipe and a fluid pressure system for forcing fluid therethrough, means for indicating whether or not said pipe is vertical by a change in fluid pressure embodying: a barrel adapted to be mounted in said pipe; a valve seat in said barrel; a spider in said barrel below said seat; a valve stem slidably mounted in said spider; a valve on said stem adapted to be forced into engagement with said seat for restricting the flow offluid from said pipe through said barrel; yieldable means associated with said valve stem for forcing said valve away from said seat; a pendulum on the lower end of said stem; a pendulum rest mounted in said barrelbelow the point of suspension of said pendulum and adapted to be-engaged by the tip of said pendulum for holding said valve away from said seat against the action of a pressure fluid, and a second valve slidably mounted on said valve stem below said seat and adapted for seating engagement therewith for floating the pipe into a well.

10. A device of a barrel adapted to form a part of a pressure fluid conduit; a valve seat mounted in said barrel; a spider in said barrel below said seat; a case mounted on the under side of said spider; a valve stem slidably extending through the top of said case; a valve mounted on said valve stem above said-valve seat; yieldable means for normally forcing said valve away from said seat; a pendulum mounted in said case on the lower end of said valve stem; a pendulum rest mounted in the bottom of said case in coaxial relation with said valve stem, said pendulum rest being of less diameter than said case and of a height such that said valve is held away from said seat when the tip of said pendulum engages said pendulum rest, and a second valve slidably mounted on said the class described embodying:

and adapted for seatfor floating the barrel valve stem below said seat ing engagement therewith into a well.

11. A device of the class described embodying: a barrel adapted to form a part of a pressure fluid conduit; a valve seat mounted in said barrel; a spider in said barrel below said seat; a case mounted on the under side of said spider; oppositely operating check valves in the bottom portion of said case; a valve stem slidably extending through the top of said case; mounted on said valve stem above said valve seat; .yieldable means for normally forcing said valve away from said seat; a pendulum mounted in said case on the lower end of said valve stem; a pendulum rest mounted in the bottom of said case in coaxial relation with said valve stem, said pendulum rest being of less diameter than said case and of a height such that said valve is held away from said seat when the tip of said pendulum engages said pendulum rest, and a second valve slidably mounted on said valve stem below said seat and adapted for seating engagement therewith for floating the barrel into a well.

12. A device of the class described embodying: a barrel adapted to form a part of a pressure fluid conduit; a valve seat mounted in said barrel; a spider in said barrel below said seat; a case a valve mounted on the under side of said spider; op-

positely operating check valves in the bottom poriicn of said case; a valve stem slidably extending through the top of said case; a valve'mounted on said valve stem above said valve seat; yield-able means for normally forcing said valve away from said seat; a pendulum mounted in said case on the lower end of said valve stem; a pendulum rest mounted in the bottom of said case in coaxial relation with said valve stem, said pendulum rest having a concave top surface of smaller diameter than said case adapted to be engaged by the tip of said pendulum upon a, downward movement of said valve thereby holding said valve away from said seat, and a second valve slidably mounted on said valve stem below said seat and adapted for seating engagement therewith for floating the barrel into a well.

13. In combination with a drill pipe and a fluid v pressure system for forcing drilling fluid therethrough, means for indicating whether or not said pipe is vertical by a pressure change in said fluid embodying: a valve seating annulus in the passage through said pipe; a reciprocable valve structure in said drill pipe associated with said valve seating annulus and adapted to receive a thrust force from said drilling fluid; gravity actuated means associated with said valve structure and controlled by the verticality of said pipe for governingthe movement of said valve structure relative to said valve seating annulus by said drilling fluid, and means for moving the valve structure into seating engagement with the valve seating annulus for floating the drill pipe into a. well.

14. In combination, a valve structure adapted for mounting in a drill pipe, gravity actuated means governing operation of the valve structure whereby the valve structure restricts flow of fluid through the drill pipe when the drill pipe is inclined from the vertical, and means for operating the valve structure to restrict flow of fluid through the drill pipe for floating the drill pipe into a well.

15. In combination, a valve structure adapted for mounting in a drill pipe, and gravity actuated means governing operation of the valve structure whereby the valve structure restricts flow of fluid through the drill pipe when the drill pipe is inclined from the vertical, the valve structure being also adapted for operation to restrict flow of fluid through the drill pipe for floating the drill pipe into a well.

16. In combination, a valve structure adapted for mounting in a drill pipe, and gravity actuated means governing operation of the valve structure whereby the valve structure restricts flow of fluid through the drill pipe when the drill pipe is inclined from the vertical, the valve structure being also adapted for operation ungovemed by the gravity actuated means for floating the drill pipe into a well.

17. In combination, a valve seating annulus adapted for mounting in a drill pipe and having a valve seating surface at each of its upper and lower sides, a valve above and cooperating with the upper valve seating surface, gravity actuated means holding the valve away from said upper valve seating surface when the drill pipe is vertical, and a. second valve below and cooperating with the lower valve seating surface for floating the drill pipe into a well.

18. In combination, a valve seating annulus adapted for mounting in a drill pipe and having a valve seating surface at each of its upper and lower sides, a valve above and cooperating with the upper valve seating surface, gravity actuated means holding the valve away from said upper valve seating surface when the drill pipe -is vertical but permitting movement of the valve toward said upper valve seating surface for restricting flow of fluid through the drill pipe when said pipe is inclined from the vertical, and a. second valve below and cooperating with the lower valve seating surface for floating the drill pipe into a well.

19. In combination, a restricted passageway in the bore of a drill pipe, a valve above and movable toward said restricted passageway, a stem for the valve, gravity actuated means for holding the valve away from the restricted passageway when the drill pipe is vertical, and a second valve slidable on the stem below and movable toward the restricted passageway for floating the drill pipe into a well.

20. In combination, a restricted passageway in the bore of a drill pipe, a valve above and movable toward said restricted passageway. and means for holding the valve away from the restricted passageway when the drill pipe is vertical but permitting movement of the valve toward the restricted passageway when the drill pipe is inclined from the vertical, said means including v a rest and a gravity actuated device having cooperating abutments adapted for contact within predetermined limits of inclination of the drill pipe and adapted to clear one'another beyond said predetermined limits, said abutments presenting not more than a line of contact each to the other when the inclination of the pipe is at said predetermined limits.

21. In combination, a restricted passageway in the bore of a drill pipe, a valve above and movable toward said restricted passageway, and means for holding the valve away from the restricted passageway when the drill pipe is vertical but permitting movement of the valve toward the restricted passageway when the drill pipe is inclined from the vertical, said means including a rest and a gravity actuated device having cooperating abutments adapted for contact within predetermined limits of inclination of the drill pipe and adapted to clear one another beyond said predetermined limits, said abutments when contacting providing an inclined contact for centerlng the gravity actuated device relative to the rest.

22. In combination, a restricted passageway in the bore of a drill pipe, a. valve above and movable toward said restricted passageway, and means for holding the valve away from the restricted passageway when the drill pipe is vertical but permitting movement of the valve toward the restricted passageway when the drill pipe is inclined from the vertical, said means including a pendulum having a pointed tip and a rest below the pendulum having an upper concave surface sloping downwardly to its center all the way from its outer periphery.

23. In combination, a valve adapted for mounting in a drill pipe, a rest, and gravity actuated means adapted to engage said rest and hold the valve in position restricting flow of fluid through the drill pipe within predetermined limits in the inclination of the pipe.

24. In combination, a valve adapted for mounting in a drill pipe, a-rest, and gravity actuated means adapted to engage said rest and hold the valve in position restricting flow of fluid through the drill pipe when the pipe is inciined from the vertical.

25. In combination, a restricted passageway in the bore of a drill pipe, a valve reciprocable in the drill pipe relative to said passageway, a stem for the valve, a guide for the stem,- and a protecting sleeve on the stem adapted to yield to permit retraction of the stem relative to theguide.

THEODORE L. LYNCH. HARRY L. RILLING.