Title:
Blowout preventer and control head
United States Patent 2231613


Abstract:
This invention relates to a blow-out preventer and control head for oil, gas and other types of wells and may be readily connected to a well casing and associated with a derrick floor and a rotary table. The primary object of this invention is the provision of a device of this character which...



Inventors:
Kay, Burke
Application Number:
US32773040A
Publication Date:
02/11/1941
Filing Date:
04/03/1940
Assignee:
Paul, Stock
Primary Class:
Other Classes:
251/197, 251/294, 277/325
International Classes:
E21B33/06
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Description:

This invention relates to a blow-out preventer and control head for oil, gas and other types of wells and may be readily connected to a well casing and associated with a derrick floor and a rotary table.

The primary object of this invention is the provision of a device of this character which will provide a positive control against the escape of liquid or gases under high pressure and which is so constructed that it may be easily and quickly closed or opened either manually or by motive power and when open will permit ordinary drilling and other operations to be successfully carried out in the well without interference from the device, and the construction further will not readily become clogged or rendered inoperative by dirt and other foreign matter and will be thoroughly lubricated to prevent sticking or freezing of the gate elements which provide the necessary seal.

Another object of this invention is the provision of an adjusting means for the gate elements to increase and decrease the pressure on said elements, the adjusting means being automatically operated to provide a maximum amount of pressure on said gate elements when the latter reach full closing position.

With these and other objects in view, the invention consists in certain novel features of construction, combination and arrangement of parts to be hereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be had to the following description and accompanying drawings, in which Figure 1 is a fragmentary side elevation, partly in section illustrating a control head constructed in accordance with my invention and showing the same connected to a well casing and associated with a derrick floor and a rotary table.

Figure 2 is a sectional view taken on the line 2-2 of Figure 1 showing a drill tube gripped thereby to effect a seal between the latter and the well casing to prevent the escape of liquid or gas.

Figure 3 is a view similar to Figure 2 with the cover or top plate of the device removed.

Figure 4 is a vertical sectional view illustrating the device.

Figure 5 is a plan view illustrating a wedge.

Figure 6 is an edge elevation illustrating the wedge.

Figure 7 is a plan view illustrating one of the gate elements.

Figure 8 is an edge view illustrating the gate element.

Figure 9 is a plan view illustrating the other gate element.

Figure 10 is an edge elevation illustrating the gate element shown in Figure 9.

Referring in detail to the drawings, the numeral 5 indicates a coupling of a conventional construction found in the upper end of a well casing 6. The coupling 5 is of the flange type to permit a control head 7 to be fastened thereto, the control head forming the subject matter of the present invention. The control head fastened to the well casing as specified locates the control head in close relation to the derrick floor 8 and the rotary table 9. The construction of the control head permits a drill stem 10 to extend therethrough and enter the well casing for a drilling operation.

The control head adapted to the well casing can be conveniently operated from a position on the derrick floor for closing the well casing against the escape of liquid or gas under excessive pressures with the drill stem still extending through the control head. By manual manipulation of the control head it can be adjusted to permit the drill stem to be withdrawn from the well casing without excessive loss of gas or liquid from the well. After the removal of the drill stem from the well casing, the control head can be actuated to bring about a positive closing of the well casing against the escape of gas or liquid.

The control head includes an elongated casing having top and bottom walls II and 12 and vertical walls 13. The vertical walls are of integral construction and the top and bottom walls are detachably secured thereto by stud bolts 14.

Integral with the top and bottom walls of the casing and arranged in opposed relation are necks !5 and 16 which provide through the casing a passage and this passage is of such a size that a drill stem or similar device may operate freely through the casing. One of the necks 15 is of the flanged type to permit fastening thereof onto the flanged coupling 5 of the well casing.

The inner face of the bottom wall 12 has formed thereon a seat 16 equipped with a facing plate or liner 17. The inner face of the top plate has formed thereon an inclined seat 18 also equipped with a facing plate or liner 19. The liners are provided with openings to match the necks 15.

Arranged in superimposed relation and for sliding movement in opposite directions between 65 the seats are gate elements 20 and 21 to which are secured stems 22 extending through opposite vertical walls of the casing, the latter having packing glands 23 to engage the stems to prevent leakage. The gates are each in the form of a plate and have formed therein a substantially oval shaped opening 24 or an opening in which a portion thereof is substantially circular in shape with an arcuate shaped portion connecting therewith and fitted to the latter-named portion is a facing strip 25 constructed of rubber or any other material suitable for the purpose.

Formed on the gates are shoulders 26. The shoulder 26 of the gate 21 may abut the inner end of one of the necks for limiting the sliding movement of said gate 21 in one direction. The shoulder 26 on the gate 20 may abut a wedge 27 for the automatic operation of the wedge when the gates have been brought in full closing position, that is, the gates positioned so that the openings thereof are out of complete registration. The wedge 27 is arranged between the gate 20 and the seat 18. This wedge acts to force the gate 20 against the gate 21 and tPjlatter against the seat 16. An adjustable stro pin 28 is threaded in the casing or the top wall 12 thereof for limiting the movement of the wedge in one direction and also may be employed for adjusting the wedge to increase its action on the gates. It will be seen that the adjusting pin 28 engages with one end of the wedge, the other end of the wedge being provided with an offset 29 apertured to receive the reduced end 30 of a jack screw 31 threaded in one of the vertical walls of the casing. A head 32 is formed on the jack screw or the reduced portion 30 thereof to prevent this portion from disconnecting from the wedge. The latter-named end of the wedge is also engaged by expansion springs 33 bearing against an end wall of the casing. The jack screw is operable from the exterior of the casing.

An operating lever 34 is pivotally mounted on the casing 7, as shown at 35, and the pivoted end thereof is in the form of an elongated head 36.

Connecting links 37 are pivoted to the ends of the head 36.

By referring to Figure 2 it will be seen that the operating lever 34 is of a double construction including parallel members 38 connected by a handle 39. The parallel members are pivoted on opposite sides of the casing and each has a head 36. Also it will be seen from Figure 2 that the connecting links 37 are arranged in pairs and extend in opposite directions and are pivotally connected to connecting pins or bolts 40 to which the stems 22 of the gates are connected. Spacing sleeves are arranged on the pins 40 between the connecting links and the stems and are indicated by the character 41.

Lubricant may be placed in the casing so that the gates and other movable parts therein will be continuously fed with lubricant to prevent sticking or freezing thereof. Also it will be seen that the gates never moved out of over-lapping relation either when open or closed and have ground fit with each other and with the seat and wedge, consequently preventing leakage between these parts. The gates when in open position align the openings thereof so that the drill stem may have free movement therethrough.

Connected to the handle 39 of the operating lever are cables 43 and 44 which extend through the derrick floor and are provided with eyelets 45 in the free ends thereof. The cable 44 passes over a pulley 46 arranged in a plane below the control head or the lowermost position of the free end of the operating lever. By pulling upwardly on the cable 43 the gates will be caused to move in the direction of each other or into or towards closing position. A pull on the cable 44 moves the control lever in a reverse direction and causes the gates to slide towards open position, that is a position of aligning the openings thereof. Whenever it is necessary to close the well against a blowout or the escape of liquid and gas, the operator pulls the cable 43 which actuates the gates to engage the drill stem and due to the cushion facings on said gates a seal will be established between said gates and the drill stem. The wedge acting on the gates prevents leakage between said gates or between the gates and the casing. The adjustment of the wedge can be brought about by turning the adjusting pin from the exterior of the casing. A slight reverse movement of the gates will free the drill stem sufficient to permit its withdrawal and the gates then may be moved into fully closed position and as the gate 20 nears full closing position it engages with the wedge 27 and causes the latter to slide therewith increasing the wedging action thereon and consequently brings about a maximum amount of pressure on the gates and the latter with the casing to provide a positive closure for the well casing. As the wedge is forced in the latter-named position by the gate 20 it will be against the action of the springs 33 so that on movement of the gates in a reverse direction or towards an open position the springs act to release the wedging action of the wedge on the gates by a reverse movement of the wedge. However, should the wedge stick and fail to move the jack screw 31 may be manually operated from the exterior of the casing to free the wedge. From the foregoing description taken in connection with the accompanying drawings it will be seen that all moving parts within the casing are thoroughly lubricated at all times to prevent sticking or freezing of these parts. Further, it will be seen that the gates move in parallel directions and with wiping contact with each other so as to clean the seats as well as the gates of any foreign matter. Also it will be noted that the gates are held in contact with each other and with the casing or seats thereof and the wedge under a tremendous and positive pressure exerted by the wedge and when moving into fully closed position have the wedging action thereon automatically increased to provide a positive closure or -oa1 against escape of gas or liquid.

While the foregoing description states that the operating lever is manually actuated, it is to be understood that power means may be connected to the cables for operating the device by motive power. This device is simple in construction and may be employed wherever it is desired to prevent the escape of gas or liquid or wherever gate valves or similar devices have been heretofore emrloyed. It is believed that the foregoing description, when taken in connection with the drawings, will fully set forth the construction and advantages of this invention to those skilled in the art to which such a device relates, so that further detailed description will not be required.

Having thus described my invention, what I claim is: 1. In a device of the class described, a casing, opposed necks on said casing and providing a passage therethrough, slidable gates in said casing and having contact with each other and provided with openings to move relative to each other and the passage for opening and closing the latter, seats in said casing and one of said seats engaging one of the gates, a wedge having an opening aligning with the passage through the casing and engaging one of the gates, means on the latter-named gate to engage said wedge to increase the wedging action thereof on the gates when the latter are in full closing position, and means for operating said gates in opposite directions.

2. In a device of the class described, a casing, opposed necks on said casing and providing a passage therethrough, slidable gates in said casing and having contact with each other and provided with openings to move relative to each other and the passage for opening and closing the latter, seats in said casing and one of said seats engaging one of the gates, a wedge having an opening aligning with the passage through the casing and engaging one of the gates, means on the latter-named gate to engage said wedge to increase the wedging action thereof on the gates when the latter are in full closing position, and means for operating said gates in opposite directions, tension means acting on the wedge, and a jack screw threaded to the casing and connected with the wedge.

3. In a device of the class described, a casing, opposed necks on said casing and providing a passage therethrough, slidable gates in said casing and having contact with each other and provided with openings to move relative to each other and the passage for opening and closing the latter, seats in said casing and one of said seats engaging one of the gates, a wedge having an opening aligning with the passage through the casing and engaging one of the gates, means on the latter-named gate to engage said wedge to increase the wedging action thereof on the gates when the latter are in full closing position, means for operating said gates in opposite directions, tension means acting on the wedge, a jack screw threaded to the casing and connected with the wedge, and an adjusting pin threaded in the casing and engaging said wedge. 4. In a device of the class described, a casing having a port, parallel gates slidable in said casing and having openings movable relative to each other and to the port for opening and closing the latter, a wedge engaging one of the gates, seats formed in said casing and one of said seats engaging one of the gates and the other seat engaging the wedge and having an inclined face to coact with the taper of the wedge, an adjusting means for the wedge, a shoulder on one of the gates to engage the wedge for increasing its wedging action on said gates when the latter are moved into full closing position, stems on said gates and extending through the casing, packing means carried by the casing to engage the stems, and an operating means carried by said casing and connected to the stems.

KAY BURKE.