US2043979A

US2043979A - Well cleaning device

Info

Publication number: US2043979A
Application number: US5774A
Authority: US
Inventors: James T Barkelew; Harold E Scantlebury
Original assignee: Individual
Current assignee: Individual
Priority date: 1935-02-09
Filing date: 1935-02-09
Publication date: 1936-06-16
Anticipated expiration: 1953-06-16

Description

Junel, 1936. J. T. BARKELEW ET AL.

WELL CLEANING DEVICE 4 Sheets-Sheet 1 Filed Feb. 9, 1955 I 721/6 Lars Jrmz Tar/Yelew. JfaraldE Sc'mzllebury June `16, 1936. J. T. BAKELEw Er AL WELL CLEANING DEVICE Filed Feb. 9, 1935 4 .sheets-sheet 2 Inl/enlaza?. far/zes ZZ arkelew.

Homey J. T. BARKELEW ET AL June 16, 1936.

v WELL CLEANING DEVICE 4 Sheets-Sheet 3 Filed F'eb. 9, 1935 s ad r.r n@Y 00 7 4 v .www om. 2 4 l, 5 I@ Y Magd# n.25 fw 5 5m? m c M md/ @m H w. lw? w.

4 Sheets-Sheet 4 www n fra. dC s. M `fa H WELL CLEANING DEVI CE J. T. BARKELEW ET AL June 16, 1936.

Patented .lune 16, 1936 UNITED STATES PATENT OFFICE wELL CLEANING DEVICE James T. Barkelew, Pasadena, and Harold E. Scantlebury, Altadena, Calif., assignors to John Grant, Los Angeles, Calif.

Application Februai-y 9, 1935, serial No. 5,774 24 claims. (c1. 16s- 19) This invention hasto do generally with wellI cleaning devices and is more particularly concerned with such devices wherein there is provided a low-pressure-holding or charge-receiving chamber with a normally closed inlet adapted to be opened at predetermined points in the well whereby the well uid, under relatively high presfrom the well, it will be understood the illustrated 20 inlet valve for said chamber and the valve-control mechanismv may be ,applied with advantage to the inlet of any type of low pressure chamber, irrespective of the manner in which the charged chamber is subsequently emptied or prepared'for re-charge, and therefore the showing `of the invention as embodied in connection with a particular type of chamber is not to be considered as limitative on such broader aspects of the invention.

In this connection it is to be noted that in dislodging foreign matter from casing perforations or otherwise promoting fluid ow by setting up fluid movement by the charging of the Areceiving chamber, (as distinguishedfrombailing) the,

matter sodislodged is ordinarily, but not necessarily, forced into the charge receiving chamber and subsequently disposed of along with the uid charge.

The device will here be described as utilized in the cleaning of casing perforations, to which use it is particularly well adapted, but this particularized description is not to be considered as in any way limitative on the adaptability of the device for other cleaning operations.

y that they may be capable of performing eflicientlyl and surely the services required. For instance, it is highly important that the inlet to the low 55 pressure chamber b e kept tightly closed until the Conditions under which it is desirable or neccleaner has reached the predetermined zone of operation and yet, in spite of that tight closure and in spite o f the usually high iiuid pressure in that zone, the inlet must be capable of practically instantaneous full-opening, under the control of 5 the operator after reaching that zone. Further, the control mechanism must not only be sure and fast in operation, but, to be fully elcient, must be of a nature which does not interfere with the rapid lowering or raising of the device to and from the zone of operation. Further, it must present little or no danger of accidental valvetripping. A

Therefore it-A is among Athe general objects of .the invention to provide a cleaner which'shall 15 have the above desirable features, as well as others which maybe pointed out to better advantage in connection with the detailed description to follow.

It may here be pointed out, however, that the present invention embodies a` novel inlet valvefor the low-pressure chamber, wherein one valve element overlies a portion of the other valve element to form a seal, both elements being movable with respect to the body member and both being so exposed that well pressure tends to move them upwardly. The overlying element; however, is latched down in a manner to resist s e,v,it following that such pressure vis effective ni-ovement under the influence of the well presset` up relative movement between the elements in a manner to seat the .underlying element on the latched element.

Accordingly, as the tool is lowered to zones of increased pressure with a consequent increased tendency for leakage between valve parts, the tighter is the valve held closed to resist such leakage, an obvious advantage. Then, when the overlying element is unlatched after the tool reaches the predetermined zone of operation, well pressure is effective to move both elements upwardly, but the upward movement of the underlying member is checked before that of the overlying element, it following that the elements are Y, relatively parted to open the inlet of the low' 45 pressure chamber. y j

Thus, we secure the eiect, entirely novel so far as we are aware, of utilizing well pressure to maintain a tight closure during descent of thel tool, and then utilizing that well pressure to open the valve once the valve-latch is released. t

In the illustrated embodiment of our invention we haveshown the valve seat as the overlying element which is initially latched against the movement under the influence of well-pressure.

and the valve stopper as the underlying element whose upward movement is checked before that of the seat when the latter is unlatched. However it will be understood that this showing is not limitative on the broader aspects of the invention wherein it is contemplated that either valve element may occupy one relative vertical position or the other.

We have also provided the valve seat member with a second seating surface in opposed relation to the inlet-seat, the single valve-stopper being moved into engagement with the second seat after the low-pressure chamber is charged, to act as a foot-valve.

Fig. l is a side elevation of a cleaning device embodying our invention;

Fig. 2 is an enlarged section on line 2-2 of Fig. 1;

Fig. 3 is an enlarged section on line 3-3 of Fig. 1, the showing of the inlet valve member of Fig. 2 being here repeated in order more clearly to relate certain of the parts;

Fig. 4 is a section on line 4-4 of Fig. 1;

Fig. 5 is a developed view ofcertain cam arrangements used in connection with the operation of the cleaner;

Fig. 6 is a view similar to Fig. 5 but showing the cam elements in changed relative position;

Figs. '1 and 8 are similar to Figs. 3 and 4, respectively, but showing the position of the parts when the inlet valve is opened; and

Figs. 9 and 10 are views similar to Figs. 7 and 8, respectively, but showing the position of the parts during withdrawal of the cleaner.

As has been previously stated, the cleaning device is particularly well adapted, but notlimited, to the dislodgment of foreign matter from the perforations of well-casing, and therefore We have illustrated the device as positioned within such a perforated casing or screen A having any suitable type of perforations, here conventionally illustrated at B. o

Body member vC of the cleaningdevice is here shown as made up of a plurality of sections coupled end-to-end, though it will be understood the showing of such sectional characteristics is not to be construed as limitative on the invention.

Threadably connected body or casing sections are indicated at I0, II and I2; section I0 (Fig. 2) serving as a head or top closure for the chargereceiving or low-pressure chamber D which is annularly defined by those sections. Attachment section I3 is threadably connected to section I0 and serves as means whereby the body member may be attached to a suspension element-cable I4, for instance. Section I I, here shown as longitudinally contracted, may be of any desirable length and may, itself, be sectional. A fort-y foot length gives chamber D a capacity ample for most operations.

Section I0 has a reduced axial bore I5 from which extends a transverse passageway I6 controlled by a spring-closed, outwardly-opening relief valve generally indicated at I1. The function of this valve is merely to relieve high pressure in the charge-receiving chamber as the tool is raised into zones of lower pressure. To facili- Atate unloading of chamber D, we preferably provide an inwardly, opening, spring-closed dump relief valve at I 8. This valve is fully described and claimed in the copending application of W. C. Erwin et al. on Well bailers, filed April 22, 1933, Ser. No. 667,439, wherein the showing of the valve is substantially identical with the present showing. It will suflice here to state that removable screw plug I9 normally closes passageway 20. When chamber D is to be unloaded, plug I8 is removed and passageway 20 is then adapted to put that chamber into communication with the atmosphere when the negative pressure therein (as created by the dumping of the iiuid) is of a value allowing spring-closed valve I8 to open under atmospheric pressure.

While, as will appear, chamber D may be unloaded by opening a valve which has dual capacity as an inlet closure and foot-valve, we have here illustrated an unloading door independent of and above said valve, the choice as to which dumping means shall be employed lying with the operator. The illustration of these two dumping mediums therefore is not to be considered as limitative of one or the other or as indicating that both are necessary.

The auxiliary dump is here shown as a removable door 2I provided in section I2, the construction and mounting of this door being duly described in said copending application Ser. No. 667,439, wherein the showing is substantially the same as herein indicated, and which application also contains claims to these features. The door lis opened by loosening screws 22 (which normally press the door inwardly to compress gasket 23 and thus provide a fluid-tight seal), and then sliding the door transversely to clear lugs 24 from overhanging lips 25, which latter define way 26.

Screwed into and depending from section I2 is tubular section 21 which may be considered a part of body member C or as an extension thereof. A valve-assembly generally indicated at V is provided in the upper end of section 21, this assembly being adapted to function alternately as an inlet valve and a foot-valve for chamber D, as will appear, though this dual capacity is not to be considered as limitative on certain aspects of the invention.

Reduced-diameter tubular section 28 is screwed into the lower end of section 21, serving as a depending extension thereon. A sleeve, generally indicated at 29, is made up of threadably connected sections 30 and 3I which are longitudinally slidable on body-

sections

21 and 28, respectively. Coupled at 32 to sleeve-section 3| is a tubular extension 33 having lateral intake ports 34 which open to intake duct G (made up of the communicating bores of tube 33 and sections 3 I ,'28 and 21) leading to valve V. A shoe or guiding nose 35 on tube 33 closes the lower end of duct G and is preferably fiuted at 36 so well-fluid may pass with minimum interference between the well casing and shoe as the tool is raised or lowered, to obvious advantage.

For controlling or effecting the opening of valve V we provide a member 31 mounted for movement longitudinally with respect to body C and engageable with well casing A, plus an operative connection between that member and valve V whereby movement of the member with relation to the body sets up or controls movement of the valve. In this particular case, member 31 is carried on sleeve-section 3|, and since the latter is telescopically arranged with respect to body-sec- Since we have chosen here to show the inveningv effect therebelow and particularly at intake ports 34, we have indicated the utilization of member 31 both as the element which is operatively connected to the valve for controlling or effecting the opening thereof, and as a packer. However it will be understood that the invention, considered in its broader aspects, is not limited to having member 31 constructed to have this packing function.

With member 31 in the form of a packer positioned above intake ports 34 (whereby the zone of operation is isolated from the fluid-column in the well casing above member 31 so the effect of a sudden charging of chamber D is more or less 'localized about the intake ports) it will be seen that the packer obstructs the space between the cleaner and well-casing and, when the packer is moved upwardly, the fluid column thereabove tends to expand it radially into tighter frictional engagement with the well-casing..v

Accordingly in raising or lowering the cleaner it is vdesirable to by-pass the fluid around the packer, but since we have here shown duct G serving both as an intake passage leading to the inlet valve and as part of the by-passage, it becomes desirable that when the duct is used for intake purposes the by-pass ports opening to that vduct above the packerbe closed off. This prevents well-uid from being drawn inwardly 'through the by-pass ports from outside the isolated intake zone, which otherwise would minimize the localizing effect within that zone when chamber D is suddenly opened to receive a charge.

Therefore, in the preferred embodiment of our invention, we have shown means operable to close the by-pass ports and have given member 31 the additional function of operating that closure, as will be described. It is to be noted, however, that the following described particularities of member 31 and the by-passage control are not to be considered as limitative on the broader aspects of the invention.

Member 31 is here illustrated as a packer of a type well known in the art, `consisting of an upwardly opening cup 38 of rubber or other suitable resilient material held against sleeve-shoulder 39 by cup-member 4U, the latter being held, in turn, by coupling 32. Cup 38 may be reenforced by spring wire eil. Hereinafter, member 31 will be referred to as a packer, but this reference is subject to the reservations noted above.

Valve-assembly V includes a seat-member, generally indicated at 632, in the form of a tube capable of limited longitudinal movement and rotation within the bore of the body section 21. It will appear, however, lthat since member 52 is movable to and from closing position, that member may also be considered a movable closure member. The seat-member ismade up of threadably connected sections 43 and 111i between which is clamped a ring-packing '45, preferably cornprising a downwardly opening cup-leather in tight peripheralengagement with

sections

21 and 13, any :duid under pressure reaching the cup from beneath tending to expand it radially into tighter sealing engagement with the opposed` walls. At the top of tube-section 2:1 and posiv tioned by nut d5, is a similar ring-packing d1,

but here the cup-leather opens upwardly so fluid pressure from above tends to expand it radially into sealing engagement with the opposed peripheral walls of

sections

21 and 55.

Projecting radially from the lower end of tubesection 43 are cam pins 48 which extend through

angular cam slots

49 and 50 in body-section 21 and sleeve-section 30, respectively, slots 5Ilprefv lerably being closed at the outer face of section 5 30 by protector-sleeve 5l welded or otherwise suitably secured to that section.

Preferably, pins 48 extend through slide-blocks 52 which have nice sliding-fit in cam slots 49, the latter inclining at about the slip-angle as pre- 10 determined by the particular forces and surfaces of contact involved. Cn the other hand, each slot has substantially

vertical portions

53 and 54 at bottom and top, respectively and an inclined connecting portion 55 of considerably steeper an- 15 glethan that of slot 49. yWhen valve V is closed, l (Fig. 3) the cam pins are at the bottom of slots 5l! and blocks 52 are at or near the bottom of slots 49.

Secured tol and projecting inwardly from sleeve 2o section 30 and extending through vertical slots 56 in body'section`21, are pins 51 which support a stop collar 55, the purpose of which will later appear. The pins, in addition to their collarsupporting function, serve as keys which, in cooperation with slots 56, permit limited relative longitudinal telescopic movement between body section 21 and sleeve section 30 but prevent relative rotation thereof, it following that during telescopic movement of the

sections slots

59 and 50 30 have no relative rotation but shift vertically with respect to one another (Figs. 5 and 6).

Tube-sections 53 and llhave

internal flanges

59 and 60, respectively, which define outlet opening 6l and inlet .opening 62, respectively, of the 35` low-pressure chamber. The flanges present vertically spaced, opposed seats B3 and tf1 between which valve-stopper or closure is adapted to play, the closure having faces 56 and 61 adapted to. have fluid-tight fit withseats t3, 64, respec- 40 tively, during certain stages of valve operation.

Closure stem t8 extends with sliding fit through spider 69, carried by bodyisection 21, and through collar 58, supported from sleeve-section 30 by pins 51, as has been described. Stem 68 has three 45

collars

10, 1l and 12 positioned with relation to spider 63 and collar 58 in the manner clearlyv shown in Fig. 3. Compression spring 13, interposed between collar 1li and spider 59, tends to hold closure 55 .upwardly with shoulders G1 and 50 in engagement, being depended upon to hold the inlet valve closed only Auntil well pressure takes over the duty, as will appear.

In describing the operation of the tool it will first be assumed it is in the condition of Figs. 55 v l to 5, inclusive,- that is, ready to be lowered to the zone of operation. In this condition it will be noted that by-pass ports 1t and 15 (provided in body-section 23 and sleeve. section 3l, respectively, at points above packer 31) are in reg- 60 istration (Fig. ll) it following that, during descent of the tool, well-fluid may by-pass around the packer through ports Sli, duct G and ports 1d,

15. The frictional engagement of packer 31 with well-casing A tends to retard downward move- 65 ment of sleeve 2Q and thus tends to hold the telescopic joint between body member C and sleeve .29 relatively contracted'as the body member is lowered. Shoulders 15, defining the upper end's of slots '55, engage pins 51 to limit the extent of this contraction and ultimately serve to thrust the sleeve and hence packer 31 downwardly through the well-casing.

lt will be seen that seat member i12, when released, is capable of moving upwardly with re- 3*'5l spect to body section 21 to an extent a (Fig. 5) that is, a distance substantially equal to the extent of therelative vertical displacement of the ends of a given slot 49. However, since member 42 cannot thus move upwardly without coincident rotation (due to the coaction of the cam pins and slots 49) and since the entry of pins 48 in vertical portions 53 of cam slots 50 prevent such rotation, the seat member is, in effect, latched in the position of Fig. 3.

The relatively small vertical clearance (less than distance a) between collar 1I and spider 69 represents the extent' of ultimate upward movement allowed to closure 65. This clearance allows full seating of closure 42, under the infiuence of spring 13 or of upwardly directed uidpressure, on face 64 of the latched-down seat member and is of an extent to compensate for reasonable wear of contacting faces of the valveparts. y

When the well-uid is entered, well-pressure is effective against the lower ends of seat member 42 and closure 65 in a manner tending to move both of them upwardly or, more broadly expressed, toward chamber D, for their upper ends are eX- posed to the relatively low or `atmospheric pressure in that chamber D. However, since seat member 42 is positively latched down, well-pressure is effective to an extent measured approximately by the differential in pressure at opposite sides of closure 65 and over a surface equal to the cross-sectional area of inlet 62 to hold the closure tightly seated on face 64, the effective valve-closing pressure increasing as the tool reaches greater depths and thus off-setting the increasing leakage tendencies.

When the cleaner reaches the zone of operation, descent of the tool is checked and limited withdrawal movement is imparted thereto by reeling-in cable I4. Since packer 31 resists upward movement, due to its frictional engagement 4with well casing A,

body sections

21 and 28 are moved upwardly with relation to sleeve 29. While camV pins 48 are thus being lifted through the vertical portions 53 of sleeve-slots 50, there is no change in the relative position of the valve-parts but body section 28 is lifted suciently to close by-pass ports 15 and thus render the by-passing ineffective so, when valve V is subsequently opened, the cleaningeffect will be localized about intake ports 34.

As cam pins 48 ride out of slot portions 53 into inclined portions 55. they are freed for movement through body-section slots 49, that is, to the left as viewed in Fig. 5. The angle of a given slot 49 is preferably approximately equal to the predetermined slip-angle, so continued upward pull on the body member tends to rotate seat member 42 and thus allow it to move upwardly with respect to body section 21, the inclined portions 55 of sleeve-slot allowing such movement'of the cam pins. Or, if slot 49 be inclined at less than the slip-angle the right hand defining wall (as viewed in Fig. 5) of slot portions 55 may be utilized as cam shoulders for forcing the cam pins through slots '49. Slots 49 linut the extent of upward movement of member 42. v

Aidng in the elevation of sleeve member 42,

` or, if the cam slots be of proper angle, actually being depended upon for elevating the seat member, is the well-pressure directed against the underside of said seat member. The iluid pressure directed against the underside of closure 65 is also initially effective in aiding or causing upward movement of the seat member but when collar 1I engages the underside of spider 69 upward movement of closure 65 is checked while member 42 continues to rise, thus raising seat 64 from closure 65 and opening inlet 62 (Fig. 7

Well-fluid is then free to rush through ports 5 34, duct G, the bore of sleeve 42, and inlet 62 into the low-pressure chamber D, the fluid carrying with it foreign matter (which is to be bailed). Where the device is used as a perforation cleaner, the in-rush sets up such move- 10 ment in the well uid surrounding the tool below the packer as to dislodge slugs of foreign matter in the perforations of the well casing. The slugs (which are sometimes broken up by the uid action and sometimes are removedintact) 15 usually, though not necessarily, are carried into chamber D along with the in-rushing fluid.

With inlet valve V opened, as in Fig. 7, it will be seen that cam lugs 48 are in line with vertical portions 54 of cam slots 50 and that the lower- 20 most stem-collar 12 engages the underside of stop-collar 58. Accordingly.' upon continued withdrawal movement of body C, closure 65 is held from further upward movement by collar 58 while seat-member 42 rises with body section 21 25 -(the relative movement between the sleeve 29 and of closure 65 to close outlet opening 6I, valve V 30v 'thereafter serving as a foot-valve to retain the charge in chamber D (Figs. 9 and l0). During the withdrawal movement which accomplishes the shifting of closure 65 from the position of Fig. to that of Fig. 9, body section 28 has been drawn 35 above by-pass ports 15 (Fig. 10) it resulting that upon subsequent elevation of the charged cleaner, well fluid is again free to by-pass the packer.

When the parts are in the position of Figs. 40 9 and 10, (the charging being completed and the by-pass fully open) sleeve 42 is, in eiect, latched in its uppermost position with respect to body section 21, for it cannot travel downwardly without rotation with respect to section 21 and this 45 rotation is prevented by the presence of cam lugs 48 in vertical portions 54 of sleeve-slots 50 (Fig. 6). With member 42 held in its uppermost position with respect to section 21 and with closure 65 engaging seat 63, continued upward movement 50 of body C acts through stem 68, head 12, collar 58 and vpins 51 to drag sleeve 29 and packer 31 upwardly along with the body.

During the elevation of the charged cleaner, there arises a differential between the internal 55 and external pressures imposed on the cleaner body, but relief valve I1 allows a bleeding of chamber' D to reduce the higher internal pressure and thus eliminate danger of bursting and allows subsequent unloading without danger or in- 60 convenience to the operator.

After the cleaner is. fully withdrawn from the well, chamber D may be unloaded in either of two ways. For instance, door 2| may be opened to 'discharge the material thereabove, such built- 65 up internal pressure as remains in the chamber and generally as measured by the strength of the relief-valve spring, giving the material an initial outward impulse. To prevent a substantial negative pressure from developing in the cham- 70 ber which would otherwise prevent complete unloading, plug I9 may b removed to permit innow of air through valve I8 to the top of chamber D. Or the unloading may be accomplished as follows: with shoe 35 resting on the derrick iioor 75 rao or the bottom of a. receiving-sump, body C is lowered to a position where, due to the relative longitudinal or telescopic contraction of the body and sleeve 29, seat member 42 has been cammed down with relation to section 2l and closure 65,

outlet 6| thus being opened to permit discharge f from .chamber D through duct G and ports 34. When the chamber is emptied, all parts of the device are returnable to the positions of Fig. 3 ready to receive a new charge.

While we have illustrated and described the preferred embodiment of our invention, it will be understood this is to be considered as illustrative of and not limitative on the broader aspects of the invention, for various changes in design, structure and arrangement may be made without departing from the spirit and scope of the appended claims.

We claim: l. In a well-cleaning device, a body having a low-pressure chamber and an inlet therefor, a

seat member and a closure member cooperating to control fluid-now through the inlet, both said members being movable upwardly with respect to said body, and being individually movable ver-l tically with respect to eachother to open the inlet.

2. In a well-cleaning device, a body having a low-pressure chamber and an inlet therefor, a seat member and a closure member cooperating to control duid-flow through the inlet, both said members being movable upwardly with respect to said body, and being individually movable vertically with respect to each other to open the inlet, and releasable means adapted to -holdsaid members against such movement.

3. In a well-cleaning device adapted to belowered through a well casing, a body having a lowpressure chamber and an inlet therefor, a seat member and a closure member cooperating to control duid-flow through the inlet, both said members being movable upwardly with respect to said body, and being individually movable vertically with respect to each other to open the inlet, and means shiftably carried on the body and operatively connected to one of said members to releasably hold the members against such movement, said holding means being adapted to be released by virtue of predetermined movement of the body with respect to the casing.

4. In a well-cleaning device adapted to be lowered through a Wellcasing, a body having a lowpressure chamber and an inlet therefor, a seat member and a closure member' cooperating to control fluid-flow through the inlet, both said members being movable upwardly with respect to said body, and being individually movable vertically with respect to each other to open the inlet, and means shiftably carried on the body and engaging the casing, said means being 'operatively connected to one of said members to releasably hold the members against such movement, said holding means being adapted to be released by virtue of withdrawal movement of the body with respect to the casing.

5, In a well-cleaning device, a body having a low-pressure chamber and an inlet therefor, a seat member having a pair of vertically spaced and opposed seats, and a closure member between the seats, both said members being movable upwardly with respect to the body and said members being individually movable with respect to each other to engage the closure member sevmembers being upwardly movable with respect `to the body under the influence of well-pressure chamber, a downwardly facing annular seat on low-pressure chamber and an inlet therefor, a. seat member having a pair of vertically spacedl and opposed seats, a closure member between the seats, both said members being movable upwardly with respect to the body and said members 5 being individually movable with respect to each other to engage the closure member selectively with said seats, releasable means adapted to hold said members against up-ward movement with the closure engaging the upper seat, and means 10 operative after saidholding means is released to move said closure to the lower seat.

7. In a well-cleaning device, a body having a low-pressure chamber and an inlet therefor, a valve for lsaid inlet, releasable means associated 15 with the v'alve to render well-pressure normally effective to hold the valve closed, and means operative upon the release of the iirst mentioned means to render well-pressure effective to open the valve. i 20 8. In a well-cleaning device, a body having a low-pressure chamber and an inlet therefor, a valve for the inlet and embodying a seat member and a cooperating closure member, both said members being movable upwardly with respect to 25 the body member under the inuence of wellpressure, releasable means associated with one of Y the members to hold it against upward movement and thereby rendering well-pressure effective to close the valve, and means eil'ective upon release Vof the rst mentioned means to vstopupward releasably limited in its upward movement, and 45 l means eiectivewhen said one member is moved upwardly to stop upward movement of said other member in a position spaced below said one member in its elevated position.

10. In a well-cleaning device, a body havinga 504,

low-pressure chamber and an inlet therefor, a' seat-member and a closure-member cooperating to control fluid-flow through the inlet, both said directed thereagainst,l releasable means adapted to hold said seat-member against such movement, the closure member engaging the seat-member when the latter is so held and being thereby releasably limited in its upward movement', and means effective when said seat-member is movedupwardly to stop upward movement of said closure member in a position spaced below said seatmember in its elevated position.

l1. In a well-cleaning device, a body having a 65 low-pressure chamber, a seat member embodying a tube having sliding t in a'body-bore below and with its bore in communication with the the` tube, releasable means holding the tube against upward movement in the body-bore, a closure below and kmounted for vertical movement with respect to the seat, the lower ends of the tube and closure being adapted to be exposed bv to well-pressure and the closure normally en- @5i gaging the seat, means for releasing the holding means to allow upward movementl of the tube and closure under the influence of well-pressure, and a stop on the body limiting the extent of upward movement of the closure to less than that of the tube. l

12. In a. well-cleaning device, a body having a low-pressure chamber, a seat member embodying a tube having sliding t in a body-bore below and with its bore in communication with the chamber, vertically spaced, opposed annular seats in the bore of the tube, releasable means holding the tube against upward movement in the body-bore, a closure in the tube-bore between the seats and mounted for vertical movement with respect thereto, the lower ends of the tube and closure being adapted to be exposed to well-pressure and the closure normally engaging the upper seat, means for releasing the holding means to allow vupward movement of the tube and closure under the influence of well-pressure, a stop on the body limiting the extent of upward movement of the closure to less than that of the tube, and means for subsequently moving the closure into engagement with the lower seat.

13. In a well-cleaning device, a body having a low-pressure chamber, a seat-member embodying a tube mounted for vertical movement through a body-bore below the chamber, the tube-bore being in communication with said chamber, a downwardly-facing annular seat on the tube, a sleeve mounted on the exterior of the body lfor limited longitudinal movement, a pin on the tube and extending through angular slots in the body and sleeve, all in a manner whereby relative longitudinal movement of the body and sleeve allows relative longitudinal movement between the body and tube; a closure below and mounted for relative vertical movement with respect to the tube to open and close the tube-bore at the seat, and means on the body limiting the extent o f upward movement of the closure to less than that of the tube.

14. In a well-cleaning device adapted to be lowered through a well-casing, a body having a low-pressure chamber, a seat-member embodying a tube mounted for vertical movement through a body bore below the chamber, the tube-bore being incommunication with said chamber, a downwardly facing annular seat on the tube, a sleeve mounted on the exterior of the body for limited longitudinal movement, a pin on the tube and extending through angular slots in the body and sleeve, all in a manner whereby relative longitudinal movement of the body and sleeve allows relative longitudinal movement between the body and tube, means on the sleeve and engageable with the well-casing to effect such relative longitudinal movement upon withdrawal movement of the body, a closure below and mounted for relative vertical movement with respect to the tube to open and close the tube-bore at the seat, and means on the body limiting the extent of upward movement of the closure to less than that of the tube.

15. In a. well-cleaning device, a body having a low-pressure chamber, a seat-member embodying a tube mounted for vertical movement through a body-bore below the chamber, the tubebore being in communication with said chamber, a downwardly-facing annular seat on the tube, a sleeve mounted on the exterior of the bodyA for limited longitudinal movement, a pin on the tube and extending through a pair of angular Slots provided, one each, in the body and sleeve, the sleeve-slot having a lower portion extending parallel to the sleeve axis, a closure below and mounted for relative vertical movement with respect to the tube to open and close the tube-bore at the seat, said pin being in said lower portion of the sleeve-slot when the closure is in bore-closing position, and means on the body limiting the extent of upward movement of the closure to less than that of the tube.

16. In a well-cleaning device, a body having a. low-pressure chamber, a seat-member embodying a 'tube mounted for vertical movement through a body-bore below the chamber, the tube-bore being in communication with said chamber, a downwardly-facing annular seat on the tube, a sleeve mounted on the exterior of the body for limited longitudinal movement, a pin on the tube and extending through a pair of angular slots provided, one each, in the body and sleeve, the sleeve-slot having upper and lower portions extending parallel to the sleeve axis a closure below and mounted for relative vertical movement with respect to the tube to open and close the tube-bore at the seat, said pin being in said lower portion of the sleeve-slot when the closure is in bore-closing position and in said upper portion of the sleeve slot when the closure is out of boreclosing position, and means on the body limiting the extent of upward movement of the closure to less than that of the tube.

17. In a well-cleaning device, a body having an external packer and having a low-pressure chamber and an inlet thereto, there being a bypassage around the packer, a valve for said inlet, releasable means associated with the valve to render well-pressure normally effective to hold the valve closed, said by-passage being open when the valve is closed, means shiftable on the body and effective rst to close the by-passage and then to free said releasable means, and means operative then to render well-pressure eiective to open the valve.

18. In a well-cleaning device, a body having an external packer and having a low-pressure chamber and an inlet thereto, there being a bypassage around the packer, a valve for said inlet, releasable means associated with the valve to render well-pressure normally eiective to hold the valve closed, said by-passage being open when the valve is closed, means shiftable on the body and effective rst to close the by-passage and then to free said releasable means, and means operative then to render well-pressure eiective to open the valve; said shiftable means subsequently being eiective to re-open the bypassage.

19. In a well-cleaning device, a body having a vertically extending low-pressure chamber and an inlet for the chamber near one end thereof, a seat member and a closure member cooperating to control fluid-flow through the inlet, both said members being movable vertically with respect to said body towards the low-pressure chamber, and being individually movable vertically with respect to each other to open the inlet.

20. In a well-cleaning device, a body having a vertically extending low-pressure chamber and an inlet for the chamber near one end thereof, a seat member and a closure member cooperating to control fluid-now through the inlet, both said members being movable vertically with respect to said body towards the low-pressure chamber, and being individually movable vertically with a seat member having a pair of vertically spaced respect to each other to open the inlet, and releasable means adapted to hold said members against such movement.

21. In a well-cleaning device, a body having a vertically extending low-pressure chamber and an inlet for the chamber near one end thereof, a seat member and a closure member cooperating to control fluid-now through the inlet, both said members being movable vertically with respect to said body towards the low-pressure chamber, and being individually movable vertically with respect to each other to open the inlet, and means shiftably carried on the body and operatively connected to one of said members to releasably hold the members against suchv movement, said holding means being adapted to be released by virtue of predetermined movement of the body with respect to the casing.

22. In a well-cleaning device, a body having a vertically extending low-pressure chamber and an inlet for the chamber near one end thereof,

' dividually movable with respect to each other to engage the closure member selectively with said seats.

`23. In a well-cleaning device, a body having a. vertically extending low-pressure chamber and an inlet for the chamber near one end thereof,

and opposed seats, and a closure member between the seats, both said members being `movable with respect to the body towards the low-pressure chamber, and said members being individually movable with respect to each other to engage the closure member `.selectively with saidvseats, releasable means adapted to hold said members against movement toward the low-pressure chamber with the closure engaging one of the seats, and means operative after said holding means is releasedto move said closure to the other seat.

24. In a well-cleaning device, a body'having a vertically extending low-pressure chamber and an inlet for the chamber near one end thereof, a valve for the inlet, said valve embodying a seat member and a cooperating closure member,

both said members being movable with respect to the body member towards the low-pressure chamber under the influence of well-pressure, releasable means adapted to hold one of the members against movement toward the low-pressure chamber and thereby rendering Well-pressure effectivel to close the valve, and means effective upon release o f the iirst mentioned means to stop movement of one member towards the lowpressure chamber ahead of the other member and thereby render well-pressure effective to open the valve.l y

JAMES T. BARKELEW.

HAROLD E. SCAN'ILEBURY.