US2232172A - Rotary drilling - Google Patents

Description

Feb. 18,1941. J c TUN 2,232,172

ROTARY DRILLING Filed June 16, 1938 2 Sheets-Sheet l IINVENTOR' JAMES c eem/v5 I BY A ORNEY Patented Feb. 18, 1941 UNITED 'STATES PATENT OFFICE 4 Claims.

The invention here disclosed relates to rotary drilling and particularly, pressure drilling. For practical, eflicient pressure drilling, flush joint drill pipe is required. The present invention is 5 directed particularly to pressure drilling operations with flush joint pipe.

Objects of the invention are to provide practical and efficient drive bushing structure for the flush joint drill pipe; to provide a thoroughly practical stufiing box for sealing the flush joint pipe in the casing and which can be controlled and operated against any well pressure encountered; to provide practical and effective snubbing equipment for pulling the drill pipe into the well or for controlling movement out of the well, under pressure; to provide a flow bean for passing the drilling fluid, bit cuttings and cavings while maintaining desired back pressure on the well and which may be regulated as required to compensate for cutting resulting from such flow; and to provide a simple and practical, easily read rate-of-feed indicator which will show accurately the amount and enable instant evaluation of the rate of feed under the hydraulic essure feed operations of the drill. 7

Other desirable objects and the novel features of construction, combinations and relations of parts whereby all objects of the invention are attained are set forth in the following specification, illustrated in the accompanying drawings and broadly covered in the claims. The drawings disclose certain practical embodiments of the invention but it is contemplated that various changes and modifications may be made, all within the true pirit and broad scope of the-invention.

Figure l is a broken part sectional side view i1-- lustrating a pressure drilling rig incorporating features of the invention.

40 Figure 2 is a broken part sectional side view of I 50 Patent #l,992,746 and including a one-way rotary drive bushing for flush joint pipe of the type disclosed in Fortune Patent #l,985,367.

The rotary table is indicated at 2| having the drive bushing 22 for the smooth flush joint drill 55 pipe 23.

The pistons of the two Fortune hydraulic rams appear at 25 carrying the beam or yoke 26 overstanding the rotary and equipped with arotatably mounted spider 2'! as in Patent #1,992,'746, carrying slips for supporting the pipe. Feed of 5 the drill and weight of the bit on the bottom is accurately regulated by control of the rams, as disclosed in the patent identified.

In Figure 1 the flush joint pipe is shown as sealed where it passes into the casing 28 by a 10 regulatablehydraulic stufling box 29.

' For snubbing the pipe into the well against pressure, .a long stroke snubbing ram may be employed such as indicated generally at 30 in Figure 1, the same acting in cooperation with a snubbing bar 3| engaged on the pipe and details of which appear in Figures 3 and 4.

For drilling under controlled pressure, a special flow bean is provided such as shown at 32, Fig. 1.

In order that the driller may maintain a desired controlled weight at the bit, the so-called rateof-feed indicator is coupled up with the hydraulic, as indicated generally at 33.

The hydraulic stufiing box indicated at 29 in Figure 1 is preferably constructed with a flange 56 by which it may be directly bolted to the Well head.

Compression of the packing is effected and accurately regulated in the illustration by a series of three jacks in the form of hydraulic rams 12 grouped about the box and acting on a jacking ring 13. p

Figure 1 isshown more fully in Figures 3 and 4 as embodying an upwardly tapered conical spider 81 receiving upwardly closing conical slips 3 88 having dovetail keys 89 sliding in corresponding ways in the spider. These keys are shown as projecting at the top and as carrying lugs 90 spaced to rest upon the screw-threads 9| of a screw ring 92 carried by a ring gear 93 journaled on the snubbing bar about the spider and actuated by pinion 94. The latter is indicated as carried by an outwardly projecting shaft 95, equipped with a, sprocket 9B. A loose guard 91 swivelled on this shaft keeps the chain 98 in running relation over the sprocket, which chain extends down into convenient reach of the derrick floor.

The snubbing cables 99 are shown connected with the ends of the snubbing bar and the lines of a bridle I00 are connected with the top of the bar for hoisting to position for starting a new stroke.

Downward pull on the snubbing bar through cables 99" closes and grips the slips on the drill pipe after initial engagement has been efiected between the slips and pipe. The spring IOI acting on the upper ends of the slips keeps the slips level and forces them downward in an opening direction, to the extent permitted by engagement of the slip lugs 90 with the screw-threads 9|. These are coarse heavy threads separated to provide upward clearance for the lugs 90 and hence closing movement of the slips independently of screw ring 92.

The snubbing bar slips 88 can be released from the drill pipe by turning the screw ring 92 through pull chain 98 in one direction to permit spring IOI to thrust the slips downwardlyin spider 81. Conversely, the slips can be closed upon the pipe by turning the screw ring in the reverse direction to cause the wide spaced screwthreads 9I acting on lugs 90 to lift the slips against the pressure of spring IOI. When the slips are thus engaged with the drill pipe and snubbing begins, the teeth of the slips may by digging into the drill pipe, cause further upward draw of the slips in the spider. This additional seating movement of the slips is permitted as the screw engaging lugs 90 of the slips then simply lift off the screw-threads 9|, the clearance between screw-threads permitting such free movement.

A special hydraulic snubbing ram for operating the snubbing bar is indicated generally at 30 in Figures 1 and 2, and as there shown, comprises a single long cylinder I02 mounted on legs I03 and secured against the side of the derrick by a suitable stay at the top, such as indicated at I04.

The legs of the ram carry a pair of spaced sheaves I05 at their upper ends and a pair of arms I06 which can be swung out and joined to the yoke 26 of the hydraulic, as indicated at I01, or be connected to a special snubbing head, later described. These arms carry spaced sheaves I08 'and the piston I09 of the ram carries spaced sheaves II0. A piston rod III projecting from the bottom of the ram and operating between guides I I2 carries a single sheave H3.

The two lengths of snubbing cable 99 anchored to the equalizer II4 on the base of the ram extend upwardly over and down about sheaves I10 on the piston of the ram and thence beneath sheaves I05 at the base of the ram inwardly beneath sheaves I08 at the beam of the hydraulic and upwardly to the ends of the snubbing bar 3I. The lines I for lifting the snubbing bar are connected as a bridle and then extend in a single line over a sheave II on the crown and thence downward over a guide sheave H0 at the side of the derrick, beneath and upward around sheave H3 to an anchorage on the base of the ram at 1.

In the upward stroke the piston of the ram, carrying sheaves I'I0, pulls a long loop in the snubbing cable 99 imparting a downward movement to the snubbing bar double the stroke of the ram. The downward travel of the snubbing bar keeps the slack out of the return line I00. At the end of the snubbing stroke, as the water or other pressure fluid is bled from the cylinder,

and draw works free for their own uses. All forces of the snubbing ram are under compression so that the ram requires no special anchorage. The inwardly extending snubbing arms I06 leave full head room beneath them and when not in use, may be folded outwardly against the cylinder legs. The load on the snubbing bar is divided between two cables and the stroke of the ram is doubled at the snubbing bar.

In drilling a rotary well under controlled pressure, some means should be provided to maintain substantial back pressure on the well and at the same time recover the bit cuttings and any cavings that may be carried in the circulating fluid. If the cuttings are coarse, the passage through the control device should be relatively large and the pumps would then be run at a speed suflicient to furnish the volume required to maintain the control pressure. When the cuttings are fine, the opening should be closed down, which enables a slower pump speed to maintain the required pressure.

Fixed orifices are unsuitable for carrying back pressure on a drilling well, as they limit the pump revolutions to the narrowest range and cannot be cleared when plugged with cuttings.

Existing flow beans though fully suited to the purpose for which they are designed, namely, the handling of comparatively clean oil, are wholly unsuited to present purposes, handling rotary drilling fluids heavily laden with sand and cut-tings.

The adjustable rotary flow bean indicated at 32 in Figure 1 has been designed on the recognition of the fact that any abrasive fluid passing through a restricted orifice at high velocity necessarily effects some cutting. In this invention, the cutting action is confined to those portions of the bean where it will do the least damage and so that the discharge area can be maintained constant as the bean cuts out. The returns are taken through one port shaped to pass the greatest diameter cuttings for the area open to flow. All operating mechanism is on the low pressure side and fully lubricated. No packing glands are required and replacements are easily made.

I As shown, the bean consists of a valve body I26 receiving the pressure line I 28 from the well head and a vertical passage flanged for bolting to the return line I30 to the slush pit.

A valve stem I40 provided with a hand wheel as illustrated in Fig. 1, forms means for adjustment of the flow bean.

When drilling with hydraulic feed, such as the Fortune hydraulic indicated at 25, 26 in Figure 1, at a low rate, say at approximately a foot an hour, the apparent movement of the rams is so slow that the rate of feed cannot be determined. Accordingly, there is provided the rate-of-feed instrument indicated at 33 in Figure 1 and consisting of adouble diameter drum with the smaller portion carrying a cable I54 anchored at one end and looped to carry a power weight I56. The larger portion of the drum carries a cable I58 which as indicated in Figure 1, i connected with the yoke of the hydraulic. The effect of this is that under the pull supplied by the weight, the drum will turn to the extent permitted by the feed of the hydraulic. Multiplication of such movement is effected by an internal gear, acting on the arbor of pointer I6I.

As shown in Figure 1, pointer I6I registers with an inner scale I62 showing distance of travel of the-ram.

The instrument is read in two ways.

The

upwardly about the ram arm sheaves, a pipe enactual distance traveled by the ram is read directly from the inner dial. Each revolution of the hand indicates a travel of 3". The rate of feed may be determined by checking a watch against the number of points indicated on the outer dial; thus, if it requires one minute for the pointer to traverse the space between two marks on the outer dial, it will be known instantly that the rate of feed is that of 3" per hour.

When the hydraulic is pumped up to the top of its stroke, the indicating line will be spooled off the large diameter of the drum and the weight power line will be wound up on the smaller diameter.

With the indicator described, any change of cutting rate, as small as one and one-half inch per hour, will be shown. When the driller applies weight to the bit, with the hydraulic feed, the rate-of-feed indicator will immediately show the cutting rate effected by such application of weight. A fast drilling rate with the lightest weight on the bit can therefore be maintained by watching this rate-of-feed indicator and governing hydraulic feed and table speed accordingly. As the bit becomes dulled and the area in contact with the formation increases, the additional total weight required to maintain the desired cutting rate may be added as needed.

What is claimed is:

1. A snubbing ram comprising a cylinder adapted to be mounted at the side of a derrick and having an upwardly acting piston therein, sheaves on said piston and cylinder respectively, arms extending from the base of the cylinder inwardly to the center of the derrick, sheaves carried by said arms and snubbing cables anchored to the ram cylinder and extending upwardly and thence downwardly about the piston sheaves and inwardly over the cylinder sheaves and under and gaging snubbing bar, the upwardly extending end portions of said cables being connected with said snubbing bar.

2. A snubbing ram comprising a cylinder adapted to be mounted at the side of a derrick and having an upwardly acting piston therein, sheaves on said piston and cylinder respectively, arms extending from the base of the cylinder inwardly to the center of the derrick, sheaves carried by said arms, and snubbing cables anchored to the ram cylinder and extending upwardly and thence downwardly about the piston sheaves and inwardly over the cylinder sheaves and under and upwardly about the ram arm sheaves, a pipe engaging snubbing bar, the upwardly extending end portions of said cables being connected with said snubbing bar, a rod extending downwardly fromthe piston of said ram, a sheave carried by said rod and a snubbing bar return line looped about said last-mentioned sheave.

3. A snubbing ram comprising a cylinder adapted to be mounted at the side of a derrick and having a piston therein, sheaves carried by said piston and cylinder respectively, arms extending from said cylinder inwardly to the center of the derrick, sheaves carried by said arms, a pipe engaging snubbing bar and snubbing cables extending about said sheaves and connected with said snubbing bar.

4. A snubbing ram comprising a cylinder adapted to be mounted at the side of a derrick and having a piston therein, sheaves carried by said piston and cylinder respectively, arms extending from said cylinder inwardly to the center of the derrick, sheaves carried by said arms, a pipe engaging snubbing bar and snubbing cables extending about said. sheaves and connected with said snubbing bar, said snubb-ing bar including a bar with which said cables have connection, upwardly closing slips seated in said bar and means for efiecting opening and closing movements of said slips.

JAMES C. FORTUNE. v

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