US1790904A

US1790904A - Cjmghton

Info

Publication number: US1790904A
Authority: US
Publication date: 1931-02-03
Anticipated expiration: 1948-02-03

Description

Feb. 3; 1931. a T. A. CREIGHTON 1,790,904

BLOW-OUT PREVENTER Filed June 2 1926 77mm: CRE/GHTOM Arron 1.5x

Patented Feb. 3, 1931 1,790,904

UNITED I'S'ILJAVTES PATENT OFFICE THOMAS A. CREIGHTON, OF VENTURA, CALIFORNIA Brow-our PREVENTEB Application filed June 2, 1926. Serial No. 113,296.

This invent-ion relates to blow-out prereferred to consists of an upper or pressure venters for use in oil wells or other types of and lower or seating ring with a gasket meme wells where it is desired to prevent blow-outs ber formed of some pliable or expansible mawith disastrous results to tubing and other terial interposed between the upper and lower well mechanism due to excessive gas pressure annulus members. The upper annulus is within the well, or in case the drilling should formed to receive a slip member so that the lead into oil sands which would cause said annulus and the drill stem may be locked a gusher. 5 in a given-position. The gasket and lower The invention has for an object the novel annulus will drop within the bowl associated 10 and useful provision, formation, construcwith the casing when the slips and thespider tion and association and relative arrangeare removed from the turn table, and a lowments of members which will efiectively preering of the drill stem will allow the upper vent gas blow-outs in wells, which is positive ring to contact with the packing or gasket in its operation, easy to handle and inexpenand the weight of the drill stem being trans- 15 sive to manufacture. ferred to the upper ring will cause said ring A still further object is to provide a blowto bear upon the gasket and mash the same out preventer which may be quickly assemagainst the drill stem and against a portion bled for use without threading*the parts of the inner surface of the bowl member. thereof over the tubing, kelly or the like. h The lower ring being formed of metal will 20 Other objects, advantages and features of act as a bufler so that the gas will not come invention may appear from the accompanyinto actual contact with the gasket. This ing drawing, the subjoined detailed descripis a precautionary measure so that if gas tion and the appended claims. should escape it would be unable to cut away In the drawing: the gasket. It is thus evident that in order 25 Fig. 1 is a fragmentary longitudinal secto blow out the well it would be necessary to tional' view of my inventionin operative posilift the entire drilling string. It is thus evition. Y dent that I have produced a simple means for Fig. 2 is a plan view of the pressure ring. 'eflectively preventing blow-outs such as are Fig. 3, is a bottom .plan'view of the same. liable to occur in well practice with particular 30 Fig. 4, is a sectional view taken on line applicationto oil wells.

4-4 Fig. 2. r Referring more particularly to the draw- Fig. 5, is a plan view of a modified form ing: my blow-out preventer cooperates with of ring. therotary drill pipe 1, sometimes called the In practicing the invention I may'incorkelly and which is square in cross section.

35 porate the device with the drill stem of a ro- The drill pipe enters the usual casing 2, on tary outfit and the drill stem, as is usual, the top-of which my blow-out preventer 3 1s projects through the spider of a turn-table, mounted. said drill stem being held in position by the The blow-out preventer homprises a shell 4 usual slip members within the spider. Besecured to the top of the casing 2 by a sleeve 40 neath the rotary turn-table and associated 5 threaded onto the shell and easing. A seat with the casing is a bowl member. In case 6 is formed in said shell upon which'the lower of accident or any indication that a gusher or seating ring? rests. This ring is provided is about to be produced, the slip might be witha central square opening8through WhlCh lifted from the spider of the rotary turnthe kelly 1 extends. A11 annular flange 9 pro- 45 tab1e,the drill stem lifted and the members jects from the upper surface of the ring 7, 96 of the mechanism dropped within the bowl which flange extends into a recess 10 formed associated with the casing, and which memon the packing ring 11. The packing ring 11 bers tend to seal the bowl so that gas or oil fits the shell f and is adapted to be pressed would not escape therefrom, and hence could against the wall of said shell and agalnst the not escape from the casing. The mechanism kelly 1 to prevent the escape of 011 orgas.

An upper or pressure ring 12 fits into the the lower surface thereof, which cooperates with a groove 14 in the packing 11 to press said packing against the sleeve and kelly when pressure is applied to said ring. A central square opening 15 is provided in the ring 12 through which the kelly 1 extends and the walls of the opening are tapered as at 16 to accommodate slips 17 the teeth of which slips bite into the kelly and thus causes the ring to support the weight of the drilling string.

In assembling the ring 12 about the kelly; which is frequently necessary, much time is lost and the threads of the kelly are damaged by threading the ring thereon. I have provided a means, whereby the ring 12 can be assembled at any point on the kelly, .comprising a. block 18 which fits into a slot 19 cut through said ring into the opening 15, and of the same width as said opening; so that the kelly can pass there-through. The

walls of said slot and the sides of the block are tapered to provide a seat for said block. Dovetail notches 20 are provided in the ring 12 and cars 21 on the block 18 enter said notches thereby holding the block in position and preventing it from sliding out. It will be seen that the inner edge of the block 18' forms one side of the opening 15, and re moval of the block will enable the ring to be quickly removed from the kelly.

'In Fig. 5 I have shown a modified form of ring in which the ring 12' is made in two

pieces

22, 23. The piece 23 has dovetail Eotches 24, in which lugs 25 on the piece 22,

Assuming that the rotary is in operation and drilling is progressing, and it is noticed by the driller that mud flowing in the sump has an effervescent appearance indicating gas pressure, if the operator determines that the gas pressure is liable to become serious he stops the operation of the rotary, raises the drill stem 1 through the medium of the draw-works of the rotary, and inserts a slip or slips 17 within the beveled portion 16 of the member 12 sothat the teeth of such slips bite against the sides' of-the drill stem-1. The drill stem is lifted sufiiciently to lift the drill from the bottom of the well hole and a suflicient distance so that upon a lowering of the drill tubing'the same will not again contact with the bottom of the well hole when the blow-out preventeris in position. After the slips 17 are placed within the member 12 said member will be held to the stem 1, whereupon the drill stem with its connected pipe may be lowered in the well hole where the ring 12 will contact with the gasket 11, whereupon the entire load, that is the weight of the drill stem and the associated therewith, will be carried by the members 11,

12 and 7 and the shell 4. The weight of all this drilling mechanism will of course compress the gasket 11 and force the periphery thereof against a portion of the inner surface of the bowl and likewise force the gasket against the surface ofthe drill stem 1, thus making an air-tight fit.

The slips 17, are not placed in position until such a time as it is desired to pack ofi the casing, that is, the kelly rotates freely to drill the well, and is, of course, fed downwardly constantly during this operation and when the casing pressure indicates that a blow-out might occur, the slips 17 are inserted, and the weight of the tool string is permitted to rest upon the

rings

7, 12 and the packing 11, and thus begin packing off the casing; but as previously stated, during the drilling operation, the slips are not in position and consequently the kelly or square, drill stem is not connected in any way to the ring 12, and thus the rotation of the drill stem is not interfered with.

Having described my invention I claim:

7 1. The combination with a drill pipe and well casing of a shell associated with the casing, a seat in said shell, a lower ring positioned on said seat, an upper ring, a packing member positioned between said upper and lower rings, said upper and lower rings and packing member having central openings therethrough, through which the drill pipe extends, said upper ring having a slot cut therethrough communicating with the central opening, a block adapted to fit in saidslot.

and means to lock said block in position, and removable means connecting said upper ring and drill pipe whereby the weight of the drill pipe is exerted to compress the packing member.

2. The combination with a drill pipe and well casing of a shell associated with the casing, a seat in said shell, a lower ring positioned on said seat, an upper ring, a packing member positioned between said upper and lower rings, said upper and lower rings and ,packing, member having central openings therethrough through which the drill pipe extends, said upper ring having a slot cut therethrough communicating with the central opening, a block adapted to fit in said slot, said upper ring having notches cut therein, lugs on said block adapted to enter said notches whereby the block is locked in position, and slips adapted to fit into said upper ring and engage the kelly whereby the weight of the drill pipe serves to compress the packing member.

3. The combination with a drill pipe and well casing, of a shell associated with the casing, a seat in said shell, a lower ring positioned on said seat, an upper ring, a packing member positioned between said upper and lower rings, said upper and lower rings and packing member having central openings therethrough, through which the drill pipe extends, said upper ring having a slot cut therethrough communicating with the central openings, a block adapted to fit in said slot, said upper ring having notches cut therein, lugs on said block adapted to enter said notches whereby the block is locked in position; the Walls of said slot and block being tapered to provide a seat for the block, and annular rings projecting from the upper and lower rings adapted to engage the packing to force said packing against the shell and drill pipe.

In testimony whereof I' aflix my signature.

THOMAS A. CREIGHTON.