US1842116A - Plug for well tubes - Google Patents

Description

2 Sheet's-Sheet 1 Jan. 19, 1932.

Jam 19, 1932. c. A. RAsMUssEN PLUG Fon WELL TUBES 2 sheets-'sheet 2 x Filed April 14. 1930 N., v :E f 5 Z v4 QvnO 7 5 3 7/ f( 4 377066 4 8 J 5 6 4 o6 #WM z/// @,4/ Q6/ fw i A f, W M fr v. IA 2/ www if, i 0. www E agf W n Troe/vey.

Patented Jan. 19, 1932 UNITED s'raxrlssv PATENT oFFlcE CHESTE A. RASMUSSEIM F LONG BEACH, CALIFORNIA I ELU@ Foa WELL TUBES Application mea April 14,

under its own pressure, and my invention also Li relates to a unique construction of plug or packer.

' In the oil producing industry, after a well is drilled, various casings are set. If the oit bearing formation is under pressure, oil will 1J be caused to flow from the well without requiring any pumping. It is usual practice to install what is known as a flow tubing, through which the oil flows to the top end of the well, where it passes through a structure 35 called a Christmas tree and is conveyed therefrom by suitable piping to a storage. It is often desirable to change the length of the flow tubing, and at the present time to do this the well must be filled with a heavy mud to "3 hold back the oil. y

My invention consists in means whereby a casing or tubing may be closed or plugged off at any desired point below the well surface by inserting a plug in the tubing and L forcing the plug by fluid pressure supplied from the surface of the well downwardly into the tubing against well pressure until the point to be plugged off is reached. The fluid pressure supplied from the surfaceof the well, behind the plug may then be released to cause the plug to become automatically engaged or locked with the tubing, thus effectively closing the tubing at the desired point below the Well surface. Therefore, the present invention has great utility in inserting or withdrawing tubing from the well. After the portion ofthe casing above the plug has been removed or workedupon, as desired., without danger of fluid issuing from the well, the plug may thereafter be released by again applying fluid pressure from the surface of the well thereby to unlock the plug and permit the same to be floated out by well pressure in the tubing.

Although plugs of various types may be used in connection with the practice of the present invention, for purposes of illustration. a type of plug particularly adapted for the purpose is illustrated herein. In that connection an important characteristic ofthe i930. serial No. 444,120.

plug is that it has operating means which is so constructed that it may be operated by fluid pressure` above or below the plug. By controlling the pressure above the plug to be greater or less than below the same, it is possible to-operate the plug instrumentalities so that its gripping and sealing means will perform the desired function.

In the following description I will fully describe the method of my invention, and I will also describe the various forms of packers which are suitable for use in the performance of my invention. These packers in themselves constitute a part of the invention and have numerous novel characteristics which will be fully pointed out in the description.

Referring to the accompanying drawings in which I illustrate my invention,

Fig. 1 is an elevational view partly in section, showing the apparatus in the upper end of a well and showing the manner in which the plug is removed or installed in the well.

Fig. 2 is a vertical section showing the plug in the position it occupies when it is being lowered through the tubing to the point where it is to be set.

Fig. 3 is a' section corresponding to Fig. 2 showing the plug set in the tubing.

Fig. 4 is a view corresponding to Figs. 2 and 3 showing the position of the parts of the plug when they are ready to be removed through the tubing. f

Figs. 5 and 6 are sectional views corresponding to the lines 5 and 6 of Fig. 2.

Referring particularly to Figs. 1 to 6 inclusive, the method of my invention, which constitutes a hydraulic method of setting the plug, will be described. As shown best'in Fig. l. the numeral represents a well casing which has been set infa well. and the numeral 21 represents what is commonly known as an oil string. This oil string extends into the well below the lower end of the casing 20 and has a perforated strained pipe attached to the lower end thereof which is adjacent the oil sands and through which the oil may flow into the well. Connected to the upper end of the oil string is a structure'commonly known as a Christmas tree, this structure being identified by the numeral 22. The Christmas tree includes a cross 23 and lateral pipes 24 having valves 25. Connected in the oil string above and below the cross are valves 27 and 5 28 which constitute a part of the Christmas tree. Extending upward from the valve 27 is a short pipe 28 which is of substantially the same diameter as the oil string 21 and which is in axial alignment therewith. Connected to the upper part of this pipe is a cross 29, and above the cross 29 is a gate valve 30. Also connected to the cross 29 is a fluid supply pipe l31 having a valve 32, and opposite to the pipe 31 is an exhaust pipe 34 having a valve 35. Supported in a casinghead 37, which constitutes the connection between the-upper end of the oil string proper and the Christmas tree 22, is a flow tubing 40. This flow tubing 40 is installed in the well for thepurpose of providing an eduction means through which the oil may flow through the well. The oil flows upwardly through the oil tubing 40 into Vthe Christmas tree 22 and is conducted therefrom through either of the lateral pipes 24.

Referring now to Figs. 2 to 6 inclusive, l will describe the construction of a plug which constitutes a part of the invention; thereafter l will continue to describe the method of my invention.

The plug or packer, which will be generally referred to by the numeral 43, has a body 44 which is essentially cylindrical in shape. The upper part of the body 44 is in the form of a threaded shaft 45 and is separated from ,the main portion 46 of the body by means of a flange 47. The lower part of the body is in the form of a cylindrical stem 48 which is of smaller diameter than the main portion 46 so as to provide a downwardly facing shoulder 49.

Carried on the threaded shaft 45 is a nut 50, and disposed between the nut 50 and the flange 47 is a cup member 51 which is adapted to frictionally engage the oil tubing 40 and is adapted to form a seal when the pressure in the oil tubing 40 above the plug 43 is greater than the pressure below it. The cup 51 has an upwardly and outwardly extending annular lip 52 which is forced outward by the pressure in the oil tubing above it. The position of the lip 52 may be controlled by the nut 50 which may be advanced downwardly to flare this lip. The nut 50 at the upper 0nd of the body 44 and the cup 51 constitute a means whereby fluid pressure above the packer may be applied to actuate the device. These parts may be said to constitute au upper head of the bodv.

The lower end of the stem 48 has threads 54. and screwed thereon is a nut 55. This nut 55 provides an area against which the pressure in the oi'l tubing 40 below the packer may be applied to operate the packer` as will be described. The nut 55 therefore constitutes a lower head of the body 44. Surlpocket 62. Depending from the sli rounding the stem 48 above the nut 55 is a packing member 57 which is adapted to be expanded to engage the oil tubing 40 to provide a fluid-tight seal therewith. Disposed on the stem 48 above the packing member 57 is an expanding member 58, the lower end of which engages the packing member 57. The expanding member has a conical face 59, the smaller diameter of which is at its upper end. Projecting upward from the main portion of the expanding member 58 is a 'cylindrical extension 60 which terminates immediately below the shoulder 49.

Carried by the main portion 46 of the body 44 is a slip supporting member 61 which is vertically slidable on the main portion 46, and which has a cylindrical opening, through which the main portion 46 extends, and a supporting member 61 are depending exible ,n arms 63, to the lower ends of which slip elements 64 are secured. The slip elements 64 have external serrations 65 adapted to grip the oil tubing 40 and have inner conical faces 66 adapted to engage the expanding member 59. Each of the slip members 64 has a partly annular channel 67, and arranged'in each of these partly annular channels 67 is a friction ring 69 which is adapted to engage the oil tubing 40 with a relatively slight friction, which may be sufiicient to prevent the packer 43 from dropping too rapidly throughthe oil tubing 40. For normally retaining the slip members 64 in released position or in inoperative position, as shown in Fig. 2, a coil spring 70 surrounds the main portion 46 of the body 44 between a shoulder 71 of the slip supporting member 61 and a flange member 72 placed at the upper end of the stem 48 between the upper end of the cylindrical extension 60 and the shoulder 49. When the slips are in this position, the friction ring 69 holds the slips inward so that they will not engage the oil tubing 40.

An important part of my inventionis embodied in a latch means. This latch means includes a plunger 73 which is operable in a horizontal opening 75 formed in the upper end of the main portion 46 of the body 44. The plunger has a head 76 and a flange 77 at one end thereof. The flange 77 is engaged by a coil spring 78 which tends to hold the plunger in a position as shown in Figs. 3 and 4, so that the flange 77 engages a stop member 78. The left end of the plunger 73 is provided with a slot which forms a tongue 79. When the device is being lowered through the well, the tongue 79 is adapted to extend into a recess 80 formed in the upper end of the slip supporting member 61, which is held in engaging position by the spring 70, with the result that the plunger 73 is locked in retracted position. When the slips are in engaged position, as shown in Fig. 3, the plunger is released due to the fact that lll) the slip supporting member is moved downward, and it will occupy the position shown in Fig. 3.

Returning now to the fluid pressure method of plugging and unpluggmg a casmg or tubing in a Well, I Will again refer to Fig.

When it is desired to install the plug 1n vthe well, the valves are closed, and the valve 27 is also closed. This valve 27 is normally closed except when access to the mterior of the Christmas tree is desired'. The valve 30 is opened, and the plug 43 1s dropped into the pipe 28. The valve 30 1s then closed, and the valve 31 is opened. Fluid under pressure flows through the fluid supply pipe 31 l per end of the oil tubing 40. The well fluid at this time is forced back into the formation, or, if this is inadvisable for any reason, gas may be withdrawn through the lateral pipes 8O of the casinghead 37 in order to peri mit the fluid being forced downward through the oil tubing to enter the oil string 21. When the packer has reached the desired position, which may be determined by counting the clicks as the packer passes the joints in the oil tubing 40 or by the use of a flexible measuring means which may be attached to the upper end of the body 44, such as a flexible cable 81, as shown in Fig. 9, the packer is then operated to form a seal in the oil tubing 40. This is accomplished bv' closing the valve 32 and opening the valve in theexhaust line 34. This reduces the pressure in the oil tubing 40 above the packer and causes the body 44 to move upward relative to the slip supporting member 61 and the slip members 64. Attention is called to the fact that the change in pressure is rather quick, and there is a frietional engagement of the friction ring 69, both of which result in a relative movement between tbe bodv and the parts 61 and 64. The expanding member 58 thus is moved upward relative to the slip members 64. and tbe slip members G4 are forced outward into gripping engagement with the oil tubing 40,'

as shown in Fig. The well pressure then causes a relative movement between the bodv 44 and the expanding member 58, with the result that the space between the expanding member 58 and the nut 55 is reduced, thus causing the packing member 57 to be expanded and to form a fluid-tight seal within the oil tubing 40.

The portion of the oil tubing 40 above the packer 43 is now accessible and may be removed or worked upon. This removing of the oil tubing 40 does not constitute a part of this present invention but may be accomplslied by use of apparatus disclosed in my copending application, Serial Number 445,650. If the work o`n the upper part of the oil'tubing 40 has been completed, the valve 35 is closed and the valve 32 is opened so that a fluid pressure may again be obtained in the upper part of the oil tubing 40. This fluid pressure must be greater than the well pressure so that the body 44. may be moved downward relative to the slip supporting member 61 and the slip members 64. When this occurs, the parts will occupy the positions shown in Fig. 4. It will be noted that the slip supporting member 61 is moved upward so that the head 76 of the plunger 73 engages the upper Wall forming the pocket 62 which locks the slip supporting member and the slip members in retracted position. The slips are at this time above the larger portion of the expanding member 58 and lare retained in contracted position by the friction ring 69. The packer is then free to be moved to the surface of the ground. This is accomplished by closing the valve 32 and opening the valve 35. When the valve 35 is opened, the fluid in the oil tubing 40 above the packer 43 is forced therefrom by reason of the well pressure. When the packing member reaches a position in the pipe 28', as shown in Fig. 1, the valve 27 is closed and the valve 3() is opened so that the packer may be removed, The well is now ready for further production, 12nd one or both of the valves 25 may be opened.

The operation of the plug, including the lowering of it into the well, setting of it to certain positions, the releasing of it, and the raising of it to the surface of the ground, is accomplished entirely by fluid pressure; that is to say, the plugging and unplugging of the oil tubing 40 is accomplished entirely by fluid pressures which are controlled from the surface of the ground. It is impossible to control or change the well pressure, but it is possible to control and change l" the pressure of the fluid in the oil tubing above the packer, this being done by a suitable operation of the valves 32 and 35, as previously explained.

The description of the methods and packers of my invention in connection with the removal of a portion of au oil tubing is not to be construed as a limitation. As a matter of fact, my inventions are useful for formherein in detail constitute the preferred forms of the invention. I fully understand that various changes may be made without departing from the broad principle of my invention. In construing the appended claims, I desire to have the terms thereof broadly construed so as to include equivalent steps of the method or parts of the process and to include any changes in details which do not depart from the principle, spirit, and scope of my invention.

I claim as my invention:

l. In a casing plu adapted to be set in a casing, the combination of: a body; a packing means carried by said. body; actuating mechanism for actuating said packing means; and means opeiable upon a downward movement of said body relative to said actuating mechanism for non-releasably' locking said actuating mechanism in inoperative position.

2. In a casing plug adapted to be set in a casing, the combination of: a body; a packing means carried by said body; actuating mechanism for actuating said packing means; releasable means for releasably retaining said actuating mechanism in inoperative position; non-releasable means for non-releasably locking said actuating mechanism in inoperative position; and lock means for preventing tlie operation of said non-releasable means prior to an actuation of said actuating mechanism.

3. In a casing plug adapted to be set in a casing, the combination of a body; a packing r means carried by said body; actuating mechanism for actuating said packing means; means operable upon a downward movement of said body relative to said actuatin mechanism for non-releasably locking said actuating mechanism in inoperative position; and lock means for preventing the operation of said means prior to an actuation of said actuating mechanism.

4. In a casing plug adapted to be set in a casing, the combination of: a body; a packing means carried by said body; actuating mechanism carried by said body and operable upon a relative movement of said body to actualte said packing means; means normally retaining said actuating mechanism in inoperative position; a latch means adapted to hold said actuating mechanism in inoperative position; and lock means preventing the operation of said latch means prior to the actuation of said packing means.

5. In a casing plug adapted to be set in a casing. the combination of: a body; a packing means carried by said body; actuating mechanism carried by said body and operable upon a relative movement of said body to actuate said packing means; means normally retaining said actuating mechanism in inoperative position; a latch means adaptcd to hold said actuating mechanism in inoperative position; and means for causing said actuating mechanism to retain said latch means from operating.

6. An apparatus for plugging the tubing of oil and gas wells including a plug having iiuid responsive tubing gripping and releasing means, means for applying iiuid ressure above the plug to move the same into the tubing a ainst fluid pressure, means to operate the tubing gripping means by pressure from below upon release of pressure from above the plug, and means for releasing the tubing gripping and releasing means upon the application of pressure from above.

7. Means for plugging the tubing of pressure wells including a plug adapted to be inserted in the tubing against well pressure and having iuid pressure actuated gripping means and Huid pressure actuated locking means for said gripping means, means for applying fluid pressure in the tubin above the plug to overbalance pressure be ow the plug whereby the latter is forced by the fluid pressure above the plug into the desired location in the tubinv and means whereby upon the release of said pressure above the plug the pressure below the plug actuates the gripping means to its set osition, and means for reapplying the said uid pressure above the plug to release the gripping means and to lock said gripping means in released position.

8. An apparatus for plugging the tubing of pressure wells including a plug adapted to be moved and anchored in the tubing by differential'articial Huid pressure above and natural pressure below the plug, said plug having tubing gripping means and means for controlling the same, said last named means being responsive to the said diiferential pressures above and below the plug to cause the tubing gripping means to engage and release the tubing.

9. An apparatus for plugging pressure wells including a fioatable plug having locking means for holding it in a set position in the tubing and other locking means for holding said first mentioned locking means in unlocked position, and manually controlled fluid pressure means for directing a pressure fluid above the plug to overbalance the well pressure below the same thereby to force the plug to a predetermined position, means for operating the first named locking means to lock the plug in the selected position in the tubing by pressure from below upon release of pressure from above the plug, means for releasing the locking means and operating said other locking means to lock the same in released position upon the application of pressure from above the plug.

10. An apparatus for plugging the tubing of pressure wells including a plug adapted to be moved in and engaged with the tubing by differential fluid pressures above and below the plug, said plug having tubing engaging means, and manually controlled iluid pressure means operable to apply fluid pressure initially above the plug to place it in its predetermined position in the tubing, means operable by Huid pressure from below u on release ofthe fluid pressure from above t e plug to cause the engagement of the tubing en'- gaging means with the tubing, and means to release said tubing engaging means upon the reapplication of pressure from above the plug whereby it may be moved out of fluid obstructing position in the tubing.

11. Means for plugging oil and gas wells including a member adapted to be moved downward into the tubing to plug the same, normally restrained locking means carried by said member and adapted to engage with the tubing to lock the member against upward movement, means whereby uid pressure in the tubing below the member effects actuation of said normally restrained locking means to permit it to engage the tubing, and means for operating said locking means to hold it in released position upon application of pressure from above.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 7th day of April, 1930.

CHESTER A. RASMUSSEN.

Images