US2071197A - Blow-out preventer - Google Patents

Description

Feb. 16, 1937, E. ums ET A1 2,071,197

BLOWFOUT PREVENTER Feb. 16, 1937. E. BURNS ET Al. 2,071,197

y BLOW-OUT PREVENTER Filed May 7, 1934 2 Sheets-Sheet 2 www Patented Feb. 16, 1937` EMM?? T carica BLOW-OUT PREVENTER.

Erwin Burns, Los'Angeles, and Harry P. Wickersham, Huntington Park, Calif.

ApplicationMay 7, 1934, Serial No. 724,295

1 Claim.

This invention relates to a device for use on a well and relates more particularly to a control head or blowout preventer for the upper end of a well casing. A general object of this invention is to provide a simple, practical and eiective blowout preventer that is instantly operatable to control or seal ofi the upper end of a well.

In thedrilling of oil and gas wells high pressures often develop very quickly and with little or no warning. High pressures lsometimes develop in a well so rapidly that there is insufcient time to position and actuate the usual or typical packing assemblies employed in blowout preventers with the result that the well is allowed to get out of control.

An object of the invention is to provide a blowout preventer for the upper end of a well casing that includes an emergency packing means that may be instantly actuated to control the well in the event that high pressures develop.

Another object of the invention is to provide a blowout preventer including an emergency packing means normally positioned for immediate actuation by fluid pressure to control the well and prevent a blowout, and a principal or main packing means that may be easily and quickly positioned and actuated to dependably and eiectively seal oil. the well.

Another object of the invention is to provide a blowout preventer having an emergency packing means that is normally arranged in the body of the device where it is flush with the interior wall of the bodyv to not interfere with the passage or operation of tools through the body and that may be instantly actuated to temporarily fully close oi the body opening or seal about a drill pipe or other tool that may be extending into the well.

Another object of the invention is to provide a blowout preventer of the character mentioned in which the emergency or secondary packing means may be actuated totemporarily seal or close oif the well casing to permit the repair or replacement of the packer of the principal packn ing means.

Another object of the invention is to provide a blowout preventer of the character mentioned including a single simple and inexpensive-body for carrying both the emergency packing means andthe principal packing means.

A further object of the invention is to provide a blowout preventer of the character mentioned inwhich ports are provided in the body below each of the packing means for the escape lof gas pressure ,and for the introduction of mud or huid to kill the well when either packing means is in use.

Other objects and features of our invention will be better and more fully understood from the following detailed description of a typical preferredorm and application of the invention, throughout which description reference may be had to the accompanying drawings, in which:

Fig. 1 is a longitudinal detailed sectional view of the blowout preventer showing the packer in position in the body to seal about a drill pipe and illustrating in broken lines the manner in which the auxiliary packing sleeve may seal with the pipe. Fig. 2 is a top or plan view takeny as illustrated by line 2--2 on Fig. 1. Figs. 3 and 4 are transverse detailed sectional views taken as indicated by lines 3-3 and ll-4, respectively, on Fig. l and Fig. 5 is a fragmentary longitudinal sectional view of the packer removed from the body taken substantially as indicated by line 5--5 on Fig. 2.

The blowout preventer of the present invention includes, generally, a body l0 for arrangement on the upper end of a well casing C, packing means il for temporarily sealing or closing off the upper end of the casing, and a main or principal packing means i2 for sealing off the well.

The body l0 is an elongate tubular structure adapted to be attached to the upper end f the well casing C so that its central longitudinal opening i3 forms a continuationY of the opening of the casing. The body lll may be attached to the well casing C rin any suitable or practical manner. In the particular application of the invention illustrated in the drawings the lower end portion of the body l0 is externally screw-threaded and is connected to the casing C by a coupling ld, The body l0 is cylindrical in its general con- The upper portion Il of the body opening I3* is of increased diameter providing an annular internal shoulder i8 in the body. The shoulderv i8 is provided to support the packer of the means l2 and is inclined downwardly and inwardly.

The invention provides portsi9 in the wall of' the body il! below the recess I5 and similar ports `2li in the wall of the body below the shoulder I8.

I I is provided to temporarily close or seal off the.

body opening I3 when high pressures suddenly develop in the well or when the packer of the principal packing means I2 is to be replaced. It is an important feature of the invention that the packing means II isA always available and in position for operation and is adapted to be instantly operated to prevent a blowout when high pressures develop in the well. The means II is particularly simple and does not in any way interfere with the free passage and operation of drilling tools through the body I or casing C.

The packing .means II includes an annular body or sleeve 22 of packing or sealing material arranged in the recess I5. The packing sleeve 22 is formed of rubber composition, or the like, and is adapted to be contracted or actuated inwardly to close the body opening I3 `or to seal about a drill pipe P, extending through vthe body to close oi the body opening. The opening 23 of the packing .sleeve 22 is normally of the" same or of slightly less diameter than the opening I3 of the body. In accordance with the invention the packing sleeve 22 is arranged 'to close the inner side of the annular recess I providing or forming a closed chamber about the sleeve. Annular reduced tongues 24 are provided on the opposite ends of the sleeve 22 to fit inwardly diminishing annular grooves 25 in the upper and lower walls of the recess I5. The tongues 24 may be initially of greater thickness than thev grooves 25 so that they may be tightly tted in the grooves. The body I0 may be sectional to facilitate the positioning ofthe sleeve 22 in the recess I5. In the particular construction illustrated the body comprises an upperv major section IIJEL and a lower section IIJb joined by a threaded connection X extending from the lower groove 25 to the lower end of the enlargement I6. When the sections Il)a and IIJb are disconnectedvthe sleeve 22 may be easily inserted in the recess I5 without being distorted. 'Ihreading together of the connection X may put the sleeve 22 under a suitable compression strain and more tightly wedge the tongues 24 in the grooves 25. The tongues 24 may be cemented or otherwise secured in the grooves 25 to dependably attach the sleeve to the body I0 and to seal the opposite ends of the closed chamber of the recess I5.

While we have shown the drill pipe P extendlng through the body I0 and the sleeve 22 in packing or sealing engagement with the pipe, it is to be understood that the packing sleeve 22 may be designed and proportioned to be capable of sumcient inward contraction to close oi! or control the body opening when the drill pipe is removed'from the Well and to seal about a polygonal member or tool such as a polygonal drill that may be extending through the body III. The sleeve 22 is adapted to be actuated or contracted by iluid under pressure admitted to the recess I5. A port 26 is provided in the wall of the body I0 to communicate with the recess I5. A conduit 21 extends from the port 26 to a suitable source of fluid pressureA (not shown). A valve 28 may be provided in the conduit 21 to controll -or manipulation of`a packer or tools.

The main or 'principal packing -means I2 is adapted to be employed subsequent to the operation of the packing means II or when there is sulicient time to assemble and actuate its packer without danger of the' well getting out of control. The principal packingmeans I2 is operatable to fully close or pack on? the upper end of the body I0 in a manner to effectively control the well or provide for the desired production of the well. The means I2 includes a retaining or actuating member 30 on the upper end of the'body I0 and a packing assembly or packer A adapted to be lowered into the enlarged body opening I1 to seal'about the drill pipe P. The member 30 is in the nature of a ring or sleeve screw threaded on the upper end portion of the body I0. The member 30 is intended to project above the upper end of the body I0 and has an annularl inwardly projecting flange or lip 3I spaced above the upper end of the body. Studs or screws 32 may be threaded through the member 30 to prevent the member from being threaded downwardly an excessive distance on the body. The lip 3| has an internal diameter slightly greater than that of the enlarged body opening I1. Projecting lugs or ears 33 are provided on the member 30 to facilitate its handling and operation.

The packing assembly or packer A is adapted to be arranged in the enlarged body opening I1 and may be compressed or actuated by the member 30 to effectively pack off the upper end of the body. The packer A may be varied somewhat in construction, etc., without'departing from the broader aspects of the invention. However, it is preferred to employ the improved packer illustrated in the drawings as it may be easily and quickly assembled in the body and actuated to provide a positive leak tight seal. The packer A may be designed to seal about the drill pipe P as illustrated in the drawings or may be designed to fully close oi the upper end of the body opening when the tools are removed from the well: In the. case illustrated thepacker A comprises two sections B formed of a split annular body of packing 35, a split collar 36 on the upper end of the vpacking and a split collar 31 on the lower end of the packing. This laminated assembly is split at vdiametrically opposite points into the two semi-circular sections B. The packing and the collars 36 and 31 are proportioned to be readily passed downward into the enlarged body opening I1. Lips-38 may be provided adjacent the interior and exterior surfaces of the collars 36 and 31 to confine or retain the edge portions of the packing 35. Wedge shaped vridges or tongues 39 'may be provided on the inner ends ofthe collars to expand the packing 35 inwardly and outwardly when the assembly is subjected to a compressionstrain. Pins 40 extend through openings in the collar 3G and the packing 35 and thread into openingsv in the collar 31 to retain the collars and packing in their proper assembled positions. The lower collar 3l is provided with a downwardly and inwardly tapered periphery to seat on the shoulder It and support the packer in the opening I'I. Openings 4I may be provided inthe upper collar 36 to receive the threaded ends of lifting or susor outer ends of the sections B together when the packer is assembled about the pipe P. A latch M is pivoted in a recess B5 in the upper collar segment of one section B and is adapted to cooperate with a pin t6 passing through a .similar recess in the opposing end of the upper collar segment of the other section. The end or nose of the latch td projects from the end of the collar segment and a spring 4l normally yieldinglyv urges the latch intoanoperative position for engaging the pin d6. During drilling the packer A may be suspended in the well derrick in a position where it may be allowed to swing inwardly against the drill pipe P so that the inner sides of the hinged ends of the sections B strike the pipe and-cause the sections to bepivoted together, whereupon the latch M automatically cooperates with the pin d6 to latch the sections together about the drill pipe. The packer may then be slid or lowered downwardly into the enlarged body opening i'i.

Means is provided on the packer Ato be engaged by the ilange or lip 3i of the member 30' when the packer is dropped or lowered into the opening il of the body. An annular groove tu is provided inthe periphery of the upper collar 36. A split ring 5i is arranged in the groove 5@ for cooperating with the lip 3i. The ring 5i or segment in the groove portion 5t of each section B. The 'segments of the ring 5i are shiftable radially in the groove 5t and are normally urged outwardly by springs 52. Pins 53 50 limit the outward movement of the ring 5i.

The portion of the ring 5i which projects beyond the periphery of the packer has a, downwardly and inwardly inclined lower surface 55d and a fiat horizontal upper side or surface. When the 55 packer A has been arranged or assembled about @0.0i the springs 52.

65 upper side is engageable by the lip 3l. vThe member 3i! may be threaded downwardly to actuate or compress the packer to seal about the pipe P and to seal with the wall of the opening I'I.4

During the drilling of the well or at any time when there is a possibility of a blowout occurring the body I may be positioned on the upper end of the casing C. vUnder normal conditions the packing sleeve 22 is in its uncontracted condi- 75 tion Where the wall of its opening 23 is flush includes a substantially semi-circular sectionv with the wall of the body opening I3. The member 30 is normally threaded on the body I0,

its downward threading being limited by the screws 32. The opening through the device or blowout preventer is normally unobstructed permitting the free operation of tools through the casing. At the rst warning of high pressures developing in the well fluid under pressure is passed into the chamber or recess. I5 through the) conduit 2l. This fluid under pressure contracts or actuates the packing sleeve 22 "iinwardly. If a string of pipe P is extending into the well at the time'of actuation of the means H l the packing sleeve 22 tightly seals against the drill pipe -to close od the body opening i3. In the event that there are no tools extending into the well the packing sleeve 22 may be contracted or actuated inwardly to control or close off the upper end of the casing C.A Upon the actuation of the means ii as just described the conduits 2i communicating with the ports I9 may be open to permit the escape of the gas pressure or may be employed to pass mud under pressure into the well as desired or believed necessary.

Immediately following the operation of thepacking means ii as just described the packer A, which may have been suspended in the derrick, is swung inwardly against the drill pipe P so that the inner sides of its sections B strike the automatically closed about the pipe. The latch ttl automatically latches with the pin 46 upon the closing or hinging together ofl the sections A. The packer A is then lowered or dropped into the body of the blowout preventer. The ring di is automatically contracted as the packer is passed into the opening il through 'the cooperation or its surface 5t with the lip 3i.

The springs b2 return the ring segments to positions where their upper sides are engageable by the ange 3i. 'lille actuating member 3u is then threaded downwardly to actuate or compress the packer A to cause the packer to seal about the pipe P and seal with the wall of the body opening i'i. As previously pointed out the packer A may be designed to seal on the upper end of the body i@ when there are no toolsvextending through the device. The ports may be employed to permit the escape of gas under pressure. or to pass mud under pressure into the well as required. VFollowing the operation of the packing means i2 pressure may beremoved from the recess i5 to permit the packing sleeve 22 to return to its normal configuration through its resiliency. The packing means l2 dependably and eectively seals and closes oi the upper end of the body it. In the event that a leak develops about the packer A the packing sleeve 22 may be contracted or actuated inwardly by fluid pressure admitted to the recess I5 to close or seal the body opening it, whereupon the packer A may be replaced. y

The auxiliary or emergency packing means I I provided by the present invention is instantly operatable to control or seal oi the upper end. of a well casing when a blowout is anticipated. The packing meansv i i when actuated allows the packer A to be properly positioned and actuated to dependably seal oi the upper end' of the body I0 without undue haste. The body l0 of the device .is particularly simple and is provided with two sets of ports providing for the proper control of the Wellwhen either packing means 'is in use. The packing means il is positioned and available lpipe adjacent their hinged ends and are thus for immediate use but does not in any way in teriere with the normal passage and operation of tools through the device.

Having described only a typical preferred form and application of our invention, We do not wish to be limited or restricted to the specic form and application herein set forthkbut wish to reserve to ourselves any modifications or variations that may appear to -those skilled in the art or fall within the scope of the following claim.

Having described our invention, we claim:

A head for a well comprising a'lower body section to be applied to a well casing and having a. passagewayl therethrough of uniformdiameter, a circumferentially extending lip formed at the upper end of said body section having a at end portion and an outer and downwardlyl tapered side wall terminating in a fiat circumscribing shoulder, a threaded portion formed on the body section adjacent said flat circumscribing shoulder and substantially agreeing in outer circumference therewith, a cylindrical tubular packing sleeve of uniform wall thickness having an internal diameter substantially agreeing with-the diameter of the bore through the lower "body section and being formed at its lower end with a lip conforming to the lip and shoulder formed on the body section against which it seats, an

upper section threaded at its lower end to engage the threads ot the lower section and being formedv with a main bore agreeing in diameter with the outside diameter of the tubular expanding packing and a reduced bore at its upper end agreeing with the inside diameter of the tubular expanding packing, a downwardly and inwardly tapered lip carried by the section having a bore of reduced diameter and forming a groove in combination with the wall of vthe large bore of said upper section, an upwardly extending lip formed on the tubulancontractible member and seated within said section, an annular recess formed around the -wall of thelarge bore of the upper section intermediateits ends whereby an annular space will occur around the median portion of the contractible tubular packing, the longitudinal width of said recess beingless than the distance between the ends of the lips formed on the upper and-lower sections and means providing for the introduction of fluid into said annular groove to distend the median portion of contractible packing.

ERWIN'BURNS. HARRY P. WICKERSHAM.

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