Blowout guillotine

BACKGROUND OF THE IN VENTION

This invention is in the field of devices for cutting through well casines and sealing the well.

In many instances, oil and/or gas wells develop extreme pressures or for some other reason control valves and strucHires at the surface of the ground are destroyed or damaged resuming in uncontrollable loss of well fluid, and in some mstances⁸the flowing fluids are ignited and the well burns out of control’ Many proposals have been made heretofore for capping or shutting off flow from such blown out °^{r bul}™g wells but none have proven completely successful. It has been ’posed 1° ^clamP ^{a multipart hOUSing arOUnd a}above the ground surface and by means of devices within the housing to collapse and flatten the casing at some point therein to shut off flow from the well and then to perforate he casing below the closure and withdraw well fluids from the housing Such a proposal is shown in U.S. Pat. No. , , ·

Another proposal has been to bolt or otherwise secure a multipart housing around a well casing and shearing knives with shear through the casing within the housing, the shea g knives themselves then serving as a gate valve to close th well. Such a proposal is shown tn U.S. PAT. No. 1 875 .

Such proposals, however, have not been successful since the . shearing knives do not make a smooth cut and a satisfactory sea^between the knives and casing has not been achieved. Other proposals for closing blown out or burning wells involved the provision, as a permanent part of the well cas g, certain valvelike devices for shutting off flow.

SUMMARY OFTHE INVENTION

The present invention relates to a device comprising a hinged housing that may be applied to and locked around an unprepared exterior portion of a well casmg, between casing joints, in tight clamping and sealing relation thereto without modifying the well casing itself. A rotary cutter within the housing is arranged to be moved to and across the casing therein to completely sever the same and hydrau he means o the housing can then be operated to positively press the cutting disc against the severed end of that portion of the casing extending into the well to positively close and seal the ca ine against loss of well fluids or pressure. Preferably, the cutting disc is provided with means for polishing the uppe..end < surface of the severed casing to provide a perfect seal and the ace of the cutting disc adapted to sealingly engage tha polished surface is preferably provided with a surface layer of softer material, such as bronze. tn a well

The device is so constructed that it can be apphed to a well casing while a well is in normal operation as a standby safety device or it can be manipulated from a remote position to and around a well casing in a well that has already blowni or which is on fire. After the device has been manipulated in h manner set forth above to seal or close flow from the weH, th upper end of the casing above the device can be «PP^and the cutter blade then withdrawn laterally of the casing, whereupon concrete or other material may be injected into the casing to shut the well down and the device may be readily amoved for use at some other location. Preferably, a l parts of the apparatus that require manipulation or movement are com trolleiTby remotely positioned control means, whereupon the well on which the apparatus is to be employe .

BRIEF DESCRIPTION OF THE DRAWINGS

PIG. 1 is a schematic plan view of a first embodiment of the ^inVF^ClG.Tis a vertical sectional view, taken along the line 2-2 of FIG. 1;

Referring to FIGS. 1-3, numeral 2 indicates a casing extending upwardly out of an oil or gas well, although !t may be a drill string or any other conduit extending from a well. The portion of the casing illustrated is shown as bemg above the surface of the ground, although the apparatus _ti; equally adaptable to use with casings that are under water, as will °^bThe^Uapparatus comprises a housing generally indicated at 4 and comprising a first portion 6 hingedly connected as at 8 to a second^Pportion 10. The housing portion 6 is prov.ded with Irm U extending outward^ of its p.vot 8 and t e outer end f which is pivotally connected to the piston rod 14 of a hydrau lie motor device 16. The hydraulic motor devrne 16. may be remotely controlled, from a control panel 18, to forcibly swi g the housing portion 6 relative to portion 10 to the closed position shown by full lines in FIG. 1 or to the open position shown □otted fine. The casing portions 6 and 10 - respec ,ve_lyprovided with a first chamber portton 20 see FIG.

' ^The houri^portions are further provided with semteyhndrical channels 24 and 26, respectively, which face each other when the housing is closed to define a cylindrical P^^sag^ew^ through the closed housing. That passageway is so d mem sioned and configured as to tightly clamp the housing 4 to the casing 2 in sealing relationship at axially spaced P°^'^onsabove and below the chamber portion 20. As shown in FIG. 2 adapter sleeve portions 28 are positioned in the channels 24 and^P26 to accommodate the housing to the particular size o casing illustrated. It is to be understood that the channels 24 and 26 are preferably made of a diameter tc·^a— largest well casing while such adapters as shown at 28 may be provided in different sizes to adapt the apparatus for use with well casings of any smaller diameter. Preferably, the adapter . 26 are provided with circumferential grooves or teeth no shown to effect a tight grip and efficient seal against the casing ² The housing portion 10 is prov.ded with the chamber^0. tion 22 considerably larger than the chamber portion 20 an in which a slidable carriage 30 is mounted for sliding movement toward and from the casing X position.

When the carnage 30 is in its extreme ng „ · as shown in FIG. 2, it is sufficiently far from the well casing that a cutting disc 32 mounted thereon is clear and free oft e casing 2 and does not extend into the passageway defined by channels 24 and 26. The cutting disc 32 is carried by a shaf journaled in the carriage 30 and has a gear 36 fixed thereon.* second gear 38 is fixed to a drive shaft 40 that emends wardly ofthe casing portion 10 in a direction paralleled to the XeX of sliding movement of carriage 30, F.xed to ™ 30 is a pusher tube 42 which extends slidably outwardly through the rear wall of housing portion 10 through a bean g _boss 44 Thus, the pusher tube 42 may be caused to slide to the right or left, as seen in FIG. 2, to produce a correspondmg ’ movement of the carriage 30. As shown, the drive shaft 40 extends outwardly through the pusher tube 42. Referring o _ casing 2.

3,603,387

4 and loops or bails 80 are pivotally connected to the outer ends of piston rods 82 extending rearwardly from the hydraulic motors 78. The housing portion 6 is provided with ears 84 defining seats for the forward ends of the loops 80. Thus, to lock the housing portions together the loops 80 may be moved to the position shown, inwardly of ears 84, and the application of hydraulic pressure into the left-hand of the motors 78 will cause the loops 80 to apply sufficient clamping and sealing pressure to the housing sections to maintain the apparatus in fixed position on the casing 2. In all other respects the modification shown in FIGS. 4 and 5 may be identical to those already described with reference to FIGS. 1-3.

Either form of the apparatus may be applied to an accessible portion of a well casing 2 during normal operation of the well, as a safety feature to be employed only in the event of blowout or fire. On the other hand, the apparatus described may be applied to the casing 2 only after a well has blown out or caught fire. In such instance, it is essential that all operations be capable of being controlled from a remote and safe position. Any suitable guide means can be provided for guiding the housing 4 toward the well casing 2 from a remote position. Such means may take the form of trackways projected from the remote position toward the well casing. The closing 25 of the housing about the well casing and all of the described operating functions may then be controlled from a position of safety remote from the well without endangering operating personnel.

While a limited number of specific embodiments of the invention are shown and described herein, the same are merely illustrative of principles involved and other forms may be employed within the scope of the invention.