US2241477A

US2241477A - Jar

Info

Publication number: US2241477A
Application number: US352555A
Authority: US
Inventors: Chester A Rasmussen
Original assignee: EMIL J RASMUSSEN
Current assignee: EMIL J RASMUSSEN
Priority date: 1940-08-14
Filing date: 1940-08-14
Publication date: 1941-05-13
Anticipated expiration: 1958-05-13

Description

Patented May 13, 1941 f UNITED'` STATES PATENT OFFICE 2,241,477. *A Y v i ,e JAB. Y Y Chester A. Rasmussen, Long Beach, Calif., assignor of one-half lto Emil J.- Rasmussen, Longr Beach, Calif.

:Application August i4, 1940, serlaiNc. 352,555

sciaims. (crass-c7) Myinvention relates to `:lars employed to'dislodge devices and tools in oil wells.

While the principles of my invention are applicable either to 'rotary jars or to straight-pull jars, I 'elect `for the purpose of this disclosure to limit my description toa straight-pull Jar. Those skilled .in the art will find suilicient guidance herein for embodying the invention in other types of jars.

"The general object of my invention is to provide an efficient' and reliable jar 'thatis' relatively simple in structure andfis inexpensive to manufacture.

Ajar of thetypeA elected fordisclosure comprises two slidingly telescoped members on a supporting line and is caused to operate by placing 'the supporting line under tension, the stroke of the jar being. caused by the telescoped members being suddenly released for relative longitudinal movement of limited extent. It is desirable to provide for variable lengths of stroke. because various magnitudes of jarring energy are required and because the stretch of a supporting line, `which must be commensurate with the stroke, varies both with the'elasticity of thesupporting line and with theeffective length of the supporting line. It is an object of my invention to provide a jar that is adjustable with respect to the degree of stress at which thefjar operates and/or is adjustable with respect to the length of the stroke of the Jar.

Present day jars are almost all, if not all, relatively heavy in construction and While suitable for use in drill strings are entirely unsuited for light tasks. A further object of my invention is to provide ay relatively light jar of'relativelyv small dimensions that may be lowered into a well 'on -a showing my jar disposed for operation therein; k

Fig. 2 is a longitudinal sectional view of one form of my jar;

Fig. 3 is a transverse section taken on the lin 3---3v of Fig. 2; l

Fig. 4 is a transverse section taken on the broken line 4--4 of Fig. 2;

Fig. 5 is a transverse section taken on thebroken line 5 5 of Fig. 2:

Fig. 6 is, a fragmentary section of the device of Fig. 2 showing parts of the jar in released disposition.; f

' Fig. 7 is a fragmentary .view similar' to Fig. 2 showing an adjustable form of my jar; and

Fig. 8 is a transversesection taken as indicated by the broken line 8--8 of Fig. 7.

The'principal parts of the iirst formroimy in- -vention shown inFigs. 2-to 6 are:` an outer tubular member generally'designated I0 having an inwardly `directed annular slip shoulder Il; a mandrel generally designated I2 telescopedginto the outer tubular member I0;V and a radially yieldable member I3 'slidingly mounted between s the outer tubular member and the mandrel, the

member I3 having an outwardly directed annular slip shoulder I5 to cooperate with the slip shoulder II. 'I'he outer tubular member I0 and the mandrel` I2 provide, or are 'unitary with, opposite ends of the jar and either the tubular member or the mandrlmay be uppermost. In

the present construction the mandrel I2 is uppermost .and is attached tothe end of a supporting wire I6, and the tubular member I0 is adapted'for connection with a tool or other device at its lower end. y

The outer tubular member III comprises a cylinder I-l, a bushing I8 .at the upper end of the cylinder, and a 'nipple 20 at the'lower end of the cylinder having threads 2| for connecting the jar` to various devices. The bushing I8 may be made in twosections for convenience in assembling the jar-and is adapted to limit the upward movement of the mandrel relative to the outer tubular member III, the lower end oi' the bushing forming a stop shoulder 22.

'I'he annular slip shoulder II of the outer tubular member I0 is preferably tapered in both axial directions and may be formedconveniently by welding a ring of the desired conguration inside the cylinder Il. In the preferred form of my invention, both the cylinder I'I and the slip shoulder II are cut by a series, of longitudinal slots 23 which locally divide thefcylinder I1 into relatively flexible longitudinal strips 25, each of the strips carrying a segment ofthe annular slip shoulder II.

The upper end portion of the Vmandrel I2 is reduced in diameter and threaded for engagement with a weight orfsinker 21, and theupper end of the Weight 2l ris in turn adapted to receive a removable bonnet 2,8. The `pre viously mentioned wire I6 extends through a bore Y :'38 the bonnet28 and is secured to a cross-pin Y Y slip shoulder I 5.1

3| in Ya recess 32 in the upper end of the weight Inside the outer tubular member III the man- I I Adrel I2 is'formed with an impact collar 33that presents an impact shoulder 35 to strikeagainst the previously mentioned shoulder 22 of the bushing I8. At a point spaced below the irnpact collar 33-.thermandrel is reduced in diamter to form what may be termed an'annular resetting shoulder 36 that faces downward'to meet the upper end of the previously mentionedV member I3. For cooperation with the member- I3 the lower end of the mandrel isprovided with an annular stop shoulder 31 to' limit the downward movement of the member I3, a circular portion 38 to prevent radial contraction of the member I3, and a conical portion 40 to guide the Y l y Vmember I3 into a position embracing the cir-V cularportion 38. In thev particular constructionl shown in the drawing the stop shoulder 31, the circular portion 38, and the conical Yportion 40 are all provided by a stop collar 4I that is threaded onto the lower Vend of` the mandrel I2.

, V'I'lfie slidable member'I3 is tubular in general coniiguratlon and preferablythe annular slipV shoulder I5 formed thereon tapers in both axial directions. AThe member I3 is'radially yieldable at'the slip shoulder I5 by virtue of the fact that aseries of slots'42 are cut upward from vthe lower end ofthe member'to form a series of downwardly extending flexible iingers 43, each of which lingers carries a portion of the annular When the jar isinc set position ready for a jarring stroke, the various parts are in the po-V sition Vindicated by Fig. 2. It wil be noted ,that

` the slide member I3 is at its lowermost position with respect to the mandrel I2 and is supported by theY annular stopA shoulder 31 of the mandrel with the slip shoulder I5 below the slip shoulder Y II of th'e outer tubular member III'. Since the various liexble ngers 4,3 of the member I3 embrace thercircular portion 38 at 'the lower end ofthe mandrel it is apparent that at such timeA the annular slip shoulder I5 is not'free to yield by vrradial contraction.V When the jar is in the described set disposition, whatever load isrcarried by the outer tubular member I is transmitted through the slip shoulder II and the `slip'shoul- Vder I to the mandrel I2 and is transmitted through the mandrel to the wire I6. When the There is some reaction `o1` the part of the annular slip shoulder II of the outer tubular member, but it is contemplated that' the yielding action will be primarily on the part of the annularslip shoulder I5 and that the fingers 43 will be highly flexible to minimize resistance to the resetting of the jar. 1 As. soon as the annular slip shoulder Y I5 is forced past the annular slip shoulder II,

the tubular member I3 drops r'of its'own weight into the normal setposition indicated in Fig. 2.` Fig. 1 illustrates by way of example ,anarrangement for employing my jar in an oil well.

vT'lie above described jar generally designated 45 in Fig. 1 is suspended on the end of awire I6 and'is connected to a tool 46 which may be, for example, a valve-operating tool described in my copending application, Serial No'. 208,106, entitled .Producing apparatus for oil Wells. Fig. l shows thejar lowered into a string ofl tubing 41 surrounded by a casing 48. At the top of the well is a Christmas tree assembly generally designated 58 that includes an upwardly extending length of pipe 5I .coaxial with the tubing 41 t'o house the jar when lthejar isf not in use. The wire I6 extending upward from the upper end of the pipe 5I passes over a suitable sheave 62 andfhence passes downwardy through a tension indicator generally designated53 `and iinally is wound onto a drum 55. The drum55 is driven 35 of the impact collar 33 strikes the shoulder 220i the bushing I8.

Resetting of the jar for a repetition of the stroke is aeomplished bymoving the mandrel I2 downward relative to the outer tubular member I0. :Early in the downward movement Vof the mandrel, the Vlower end'of the mandrel passes withoutresistance the annular slip shoulder YI I.

- D ownward .progress of the member I3, however, [is interrupted by contact ofthe annular slip shoulder I 5 withthe annular slip shoulder II, as shown in Fig. 6, and themember I3 remains stationary relative to the outer tubular member I II until the resetting shoulder 36 ofthe down- Y wardly moving mandrel makes contact with the upperend of the member I3 and forces the Vslip shoulderA I5 downward pastV the slip shoulder by an engine 56 through aV belt 51 and a suitable clutch that isnot shown in the drawing.

After the valve operating tool 46 engages a subterranean valve in the well (not shown) and operates the valveQit is Ynecessary .to subject the tool 46 to a ljarring action to sever a shear pin in the toolthereb'y to cause the tool to release the subterraneanvalve.` ATo produce the jarring action, the operator at'the surface of the well manipulates the abovefmentioned clutch to increase the tension of the ywire I6. The'operator observes a `pointer l58 on the tension indicator 53 andl throws out the. clutch to relax the cable as Vsoon as the indicator shows the sudden drop in tension that characterizes a stroke o! the jar.' If

itis found that the jarring action has not caused disengagement of the valve operating tool 46, the operator makes sure that the wire :Is relaxed' sutiiciently to permit the jar to fbe reset and then repeats thesjarring procedure.

The jar shownfin Figs. 7 and 8 is similar in large part to the first embodiment of my invention, corresponding numbers being employed to .indicate corresponding parts. The differences involve the substitution of a modied form of 'nan- -drel I2a vfor the mandrel -I'2, the substitution of an adjustable-impact collar 33a for the previously described, impact collar 33, land the substitution of an adjustable stop member generally desig- Ananted 4 Ia for the stop collar 4 I.

The mandrel -rl2a is Vformed with a long peripheral thread 66 that is `engaged by a threaded tube 6I, the threaded tube Abeing lintegral with the stop collar 33a and extending upward through the bushing I8 at the tcp of the outer tubular member IU. An impact shoulder 35a is providedV by the upper end of the impact collar 33a Vto strike against the stop shoulder 22 of the delicate jarring operations;

bushing Il to li-mit the upward movement of the` mandrel. Rotation of the threaded tube 6I 2.'A jar-constructed as set forh:,1

` in which said tubular bodyis slit'lon'gitudinally varies the longitudinal` position ol? the impact collar 33a on the mandrel i2`a and since the tubing is exposed at its upper end, a-djustment'of the stroke may be accomplishedfrom the yexterior of the jar.

The. stop member ua which isl threaded into the lower end of the mandrel I2a has: an upper., cylindrical portion 62 of the same diameter a the mandrel to serve as an-extension of the man- 63 that leads to; an enlarged cylindrical portionk 65, -the cylindrical portion terminating Vatialn upwardly presented stop shoulder 66.. The portions 85; 65,' and the stop shoulder 66 of the, stop member lla will be recognized escorrespending to similar parts of the previously de- The material of the stop member is such that the segments T3 have substantial flexibility so that adjustment of the threaded plug 6-8 inward outward causes the enlarged cylindrical portion 65 oi' the stop member to expand and contract in diameter. It will be 'readily understood that expansion of the stop member Ila increases the effective diameter of the annular slip shoulder drei. Below the cynndrnai portion sz the stop! member la expands to form a conical portion into resilient strips at said slip shoulder.

SLA jar constructed as set forth in claim 1 in'which said enlarged portionof the mandrel .is expansile and in which adjustable means is provided to expand said enlarged portion to increase the radial extent of said yieldable member when the jar is set.

4.,l A -jarof the character described, comprisl ing: a tubular body having an inwardly prea sented slip shoulder; a radially yieldable member mounted in said body for relative movement longltudinally'thereof, said yieldable member having an outwardly presented slip shoulder for cooperation with said inwardly presented slip shoulder; a mandrel slidingly mounted in said body with said yieldable member between the body andthe mandrel, said mandrelV having an .enlarged expansile portion to prevent radial con- 1 traction of said yieldable member when the jar is l5 on the member I3 and thereby raises the point Y `o1' tension at which the jar is released. Access to the plug 68 for adjustment may be had simply by Iremoving the nipple 20 at the lower end of the outer tubular member I0.

This second embodiment vof the invention is operated in the same manner as .the ilrst form of the invention and is removed from the well for adjustment whenever necessary'. It is a relatively light device that may be lowered into a well on wire as light as 1d gauge to perform 'Ihe 'jarring action is under close control and may be easily predetermined.

-The preferred forms of my invention described herein may be widely varied by those skilled in set, a stop shoulder to limit longitudinal movement of said yieldable member relative to the mandrel-when the jar is set, and a reduced portion to permit radial contraction of said member when the jar isrreleased, thereby to permit resetting of the jar; adjustable means to vary t"the effective diameter of said expansile portion of the mandrel; and means movably mounted on 4said mandrel to cooperate with said tubular body for jarring impact, said movably mounted means being -adjustable longitudinally oi` the mandrel to vary the lengthof the stroke of the jar.

5. A jar as set forth in claim 4 in which said movably mounted means on the jar has an extension to the exterior of said tubular body whereby the movably mounted means may be adjusted from the exterior of the jar.

6. `A jar of the character described, comprising.: a tubular body having an inwardly presented slip shoulder; a radially yieldable annular lmember mounted in said body for relative movement longitudinally thereof, said yieldable member having an outwardly presented 'slip shoulder for cooperation with said inwardly presented the art without departing from my underlying a tubular body having an inwardly presented" slip shoulder; a radially yieldable member mounted in said body for relative movement having an outwardly presented slip shoulder for cooperation. with saidl inwardly presented slip shoulder; and a mandrel 'slidingly mounted in said body with said yieldable member between the lbody and mandrel, said mandrel having a shoulder to cooperate with said tubular body for jarring impact, an enlarged portion to prevent radial contraction of said yieldable member when the jar is set, a stop shoulder to limit longitudinal movement of said yieldable member relative to the mandrel when the jar is set, and a reduced portion to permit radial contraction of said member when the jar is released, thereby to permit resetting of the jar.

' vlongitudinally thereof, said yieldable memberl slip shoulder; and a mandrel surrounded by both said body and said yieldable member and movable longitudinally relative to both said body and said member, said mandrel having a shoulder to cooperate with said tubular body for jarring impact, an enlarged portion to engage `said yieldable member to hold the member in expanded disposition when the jar is set, a shoulder to prevent relative movement of .said member away from said enlarged portion when the jar is set. and a shoulder to vforce said member to contract and -to pass said inwardly presented slip shoulder for resetting of the jar.

7. A jar constructed as set forth in claim 4 in` which said enlarged portion of the mandrel is split for radial expansion and in which an adjustable wedge is provided to expand said enlarged portion.

8. A jar as set forth in claim 4 in which said enlarged portion of the mandrel has `a substantially cylindrical surface for contact with said contractile member when' the jar is set and has a conical surface to guide the contractile member to said conical surface in the setting of the jar.

9. A jar of the character described, comprising: a tubular body unitary with the lower end of the jar, said tubular member having an inwardly presented slip shoulder; a mandrel uniinwardly presented tary with the upper end of the jar and sldingly telescoped into said body,'said mandrel having yan enlarged portion and a downwardly presented shoulder; andV a radially contractile annular member around said mandrel with suiclent clearance to permit vthecontractile member t0 gravitate to said enlarged portion of the mandrel y to be held thereby against contraction, said contractile member having an outwardly presented Y4l Y Y l2,341,477'A slip shoulder to cooperate with said inwardly presented slip shoulder, said downwardly presented shoulder of the Vmandrel being disposed to `force said contractile member downward to carry said slip shoulder of the member past said slip shoulder of the tubular body when the mandrel is moved downward relative to the tubu lar member to set the jar.

' CHESI'ER A. RASMUSSEN..