US2098520A

US2098520A - Well cleaning device

Info

Publication number: US2098520A
Application number: US22297A
Authority: US
Inventors: James J Santiago
Original assignee: Individual
Current assignee: Individual
Priority date: 1935-05-20
Filing date: 1935-05-20
Publication date: 1937-11-09
Anticipated expiration: 1954-11-09

Description

Nov. 9, 1937. J. J. SANTIAGO 2,098,520

WELL CLEANING DEVICE Filed May 20, 1935 4 Sheets-Sheet l Nov. 9, 1937.

J. J. SANTIAGO WELL'CLEANING DEVICE` Filed Mary 2o, 1955 4 sheets-sheet 2 Nov.' 9, 1937. L 1. 1. sANTlAcso 2,098,520

wELL CLEANING DEVICE Nov. 9,v 1937. J. J. SANTIAGO WELL CLEANING DEVICE Filed May 20, 1935 4 Sheets-Sheet 4 Patented Not. 9,1937

Y UNITED STATES PATENT OFFICE to John Grant, Los Angeles,

Calif.

Application May 20, 1935, Serial No. 22,297

' z3 claims. (ci. 16s- 19) This invention has todo generally with well cleaning devices and is more particularly concerned with such devices wherein there is provided' a low-pressure-Vholding or charge-receiving chamber with a normally closed inlet adapted to be opened ata predetermined point in the well whereby the well vuid, under relatively high pressure, charges that chamber with sand or other foreign matter adjacent the inlet, or vsets up vsuch pressure actions `or high velocity fluidmovements as to dislodge foreign matter which may be offering .obstruction vto free passage of fluid through ssures in the formation or perforations in the well casing.

l5 While the invention is here ldescribed* in connection with a device having a single-charge lowpressure chamber adapted to be emptied after each charging and after the tool has been lifted 'from the well, it will be understood the illustrated 23 means for opening the chamber to receive well r liquid andthe control f mechanism may be applied with advantage to the inlet of any type of low pressure chamber, irrespective ofthe 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 Y. the invention.

In this connection it is to be noted that inv dislodging foreign matter from casing perfora tions or otherwise promoting fluid ilow by Set- 1 ting up fluid movemeitby the charging of' the I receiving chamber, (as distinguished' from bailing) the matter so dislodged is ordinarily, but

not necessarily, forced into the charge receiving chamber' andsubsequently disposed of along with the fluid charge.

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

,45 Conditions under'which it i's desirable or necessary to perform well cleaning operations are so well knownv to workers in the art that it will be unnecessary here to detail them. However, it is well recognized that cleaning devices of the general nature set forth above must have certain characteristics, not easy of attainment, in order that they may be capable ofperforming efliciently and` surely the services required. For instance, it is highly important that the inlet to the low pressure chamber be kept tightly closed, until the cleaner has reached th`e predetermined zone of operation and yet, in spite of that tight closure and in spite of the usually high fluid pressure in that zone, the inletmust be capable of practically instantaneous full-opening, lunder the con- 5 trol of the operator, after reaching that zone. Further, the control mechanism must not only be sure and fast in operation, but, to be fully efilcient, must be of a nature which does not interfere with the rapid lowering or raising of the de- 10 vice to and from the zonel of operation. Further, it must resent little or no danger of accidentally openi g the charge receiving chamber.

Therefore, it is among the general objects of the invention to provide a cleaner which shall l5\` have the above desirable features, as well as others which may be pointed out to better advantage in connection with theI detailed description to follow.

One of my major and more particular objects is 20 to provide a mechanism that will preclude the possibility of the charge receiving vchamber being prematurely opened as the cleaner is being lowered in the well, and which is capable of repeated operation, without the necessity for removal from the 25 well, to open the charge receiving chamber in the event the mechanism fails to do soin the ilrst operation. While, as will be understood, the invention broadly contemplates the use of varlous different types of closuresfor the low pres- 30 sure chamber whereby the latter may be opened to receive the charge of well fluid, I prefer to use a closure of the frangible disk type in which the diskis broken to.suddenly place the charge receiving chamberin communication with theV 35 well liquid, by the impact of a relatively movable disk breaking member. Also 'in accordance with my'preferred form of the invention, I utilize a disk breaking member of the spring loaded type in which the member is releasably held in cocked 4o or retracted position, relative Cto the frangible disk, by a latch element, the latter being operable to release the breaking member, causing the latter to be projected against and to rupture the u disk. 45

While I do not claim as my invention broadly the use of 'a load-and-re mechanism for opening communication with the charge receiving chamber, I have made various members and incorporated certain additional features in this'l 50 type of mechanism that characteristically distinguish the invention from similar types of mechanisms heretofore used, and in so doing have overcome various seriously objectionable features' that have heretofore limited and interfered with the successful operation of this type of well cleaner. For example, insofar as I am aware, prior well cleaning devices embodying a load-and-re type of mechanism of the general character outlined above, have necessitated cocking or latching the firing member in retracted position before the cleaner is lowered in the well, with the result that frequently the firing or disk breaking member is prematurely released while the apparatus is being lowered in the well due to sudden jarring or imparts caused by irregularities in the well. The invention entirely obviates the possibility of such occurrences due to the fact that the cleaner may be lowered to the desired position with the breaking member out of cocked position, so that accidental release cannot occur After the cleaner has been fully lowercd, then the breaking member may be cocked and released to break the disk and allow a sudden rush of well liquid into the low pressure chamber. The invention embodies a further highly desirable feature in that in the event the re member fails in one operation to break the disk, it may be reset and released as many times as may be necessary to finally break the disk, without having to remove the apparatus from the well.

The invention has many additional features and objects, but all these, as well as the aspects referred to above, will be best understood from the following detailed description of certain typi-` cal and illustrative forms of the invention.

In the drawings:

Fig. 1 is a side elevation'pf a well cleaner embodying my invention;

Fig. 2 is an enlarged longitudinal section of an upper portion of the cleaner shown in Fig. 1, the disk breaking member being shown in a released position;

Fig. 3 is a continuation of Fig. 2 illustrating the lower portion of the cleaner;

Fig. 4 is a view similar to Fig. 2 showing the disk breaking member in retracted position;

Fig. 5 is a sectional view showing the charge receiving chamber in the upper portion of the apparatus, Fig. 5 being an upper continuation of the portion of the cleaner shown in Fig. 2;

Figs. 6 and 7 are sectional views 'similar to Figs. 2 and 3, respectively, showing the parts in charged position after the disk breaking member has been released;

Fig. 8 is a section on line 8-8 of Fig. 2;

Figs. 9 and 10 are fragmentary side elevations showing the parts as viewed from lines 9-9 and III-I0 of Figs. 2 and 7, respectively;

Figs. 11, 12 and 13 are transverse sections taken on lines II-I I, I2-I2, and I3I3, of Figs. 3, 4 and 6, respectively;

Fig. 14 is a fragmentary section on line II-M of Fig."7;

Figs. 15 and 16 are sectional views similar to Figs. 2 and 3, showing a variational form of the invention;

Figs. 17 land 18 are fragmentary side elevations, partly in section, showing portions `of the variant form as viewed from lines I'I-Il and IB-IB of Figs. 15 and 16;

Fig. 19 is a fragmentary section on line IS- 9' Fig. 19;

to the dislodgment of foreign matter from the perforations of well casing, and therefore I have illustrated the device as positioned within such a perforated casing or screen C having any suitable type of perforations, here conventionally illustrated lat P.

The present cleaner construction may be regarded generally as comprising relatively longitudinally movable body and sleeve portions B and S, the lower portion of the body being in the form of a mandrel M extending through the sleeve S, as will hereinafter more fully appear. The upper section of body member B is here shown to be made up of a plurality of sections coupled end-to-end, though it will be understood that the showing of such sectional characteristics is not to be regarded as limitative on the invention.

Threadably connected body or casing sections are indicated at I0, II and I2 (see Fig. 5), section I0 serving as a head or top closure for the charge receiving or low pressure chamber IIa. Coupling I3 is threadably connected to'section III and serves as means whereby the body may be attached to a suspension element, for example cable I 4, see Fig. 1. Section I I, here shown as longitudinally contracted, may be of any desirable length and may, itself, be sectional. A forty foot length gives chamber IIa 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 valve generally indicated at I'I. 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 facilitate unloading chamber IIa, after the latter has received a charge and the cleaner is removed from -the well, I preferably provide an inwardly opening, spring-closed dump relief valve I8. This valve is fully described and claimed in Patent No. 2,059,629, issued November 3. 1936, to W. C. Erwin et al., on Well bailers, wherein the valve showing is substantially identical with the instant showing. It will suflice here to state that screw plug I9 normally closes passageway 20. When chamber IIa is to be unloaded, plug I9 is removed and passageway 20 is then adapted to put the chamber into communication with the atmosphere when the lower pressure in the chamber (as created by dumping the uid) is of a value allowing spring closed valve I8 to open under atmospheric pressure.

Screwed into the lower end of section I2 is a section 2| whose bore 22 may be considered as the inlet opening of chamber Ila, the upper end of 2l presenting an upward facing seat 23 to take a foot valve 24. Pin l25 acts as a stop to limit the upward movement of valve 24. Section I2 is fully described and claimed in the above mentioned Patent No. 2,059,629, wherein the showing of the door is substantially the same as the instant showing. The door is opened by loosening screws 21 (which normally press the door inwardly to compress gasket 28 and provide a fluidtight seal) and then sliding the door transversely to clear lugs 29 from overhanging lips 30, which latter dene way 3|.

Section 2| has

counterbores

33 and 34, containing a bushing 35 below which is a member 36 carrying a, frangible disk 31. As best shown in Fig. 8, the disk carrying member 36 is inserted in sleeve 32 a slot H2' registering with a corre- 'horizontal slot H0.

. of the body, previously referred to as the mandrel portion M of the body. The lower end ofjthjs ing member 45, preferably though not necessarily typicaL'I have shown the

packers

51 and 55 eachv 'ing to disconnect the body sections, by

pulled down against the resistance of spring 50 berwith an unbroken disk, inserted within the body. Sleeve 32 is then rotated to the left, as

'bringing slots m and ||2- around to .tbe positions into the body below bushing 35 within a. transof tubular form, adapted to be projected against verse slot 35a in the body. The mounting and the frangible disk 31 when released by thelatch disposition of the disk is fully described and device generally indicated at 41. The head 46a claimed in said Patent No. 2,059,629 wherein the of tubular member 45 preferably is tapered to showing of these features is substantially the avoid fluid constriction within bore 34, and if same as the instant showing. Disk 31 may be desired, the upper end of this head portion may madel of any suitaible frangible material, such as be provided with teeth 48 to more effectively rupglass `or other ceramic composition, and has a ture the disk when projected thereagainst. downwardly concave shape, as illustrated, so as Member 45 normally (see Fig. 2) is supported to be readily engageable by the disk breaking in engagement with the disk 31 by'a coil spring member hereinabove described. It suflices to 50 contained within a cup-shaped liner 5| innote at this point that disk 31 normally provides Serted Within body section 2| and seating 0n the a fluid-tight bottom closure for the charge reupper end of section 40. As shown in Fig. 13, the ceiving chamber Ila, and that the cleaner is bottOm flange 0f liner 5| has a Series 0f Openings lowered in the well with chamber |la empty. 5ia t0 permit uid circulation between the liner After the cleaner has been lowered to the vdepth and the Outside 0f member 45 Spring 50 bears of the Well zone to be cleaned, the cleaning operupwardly against a Shoulder 52 on the head 46a ation is then performed by breaking disk a1 to 0f member 46- Lugs 53 project radially beyond allow a. sudden rush of well liquid through the Shoulder 52 to guide member 46 within bore 54 casing perforations P and openings in sleeve S 0f the bOdY, and Serve aS StODS t0 limit the longiinto the low pressure chamber Ha, as will later tudinal travel 0f the member Within -the body be brought out. by engagement with the upper end of liner 5|, Provision is made whereby the disk carrying When member 45 iS in cocked DO SitiOn'and with member 35 maybe releasably locked within the body Shoulder 54a When the member iS in fully body, and yet rendered'removable for replace- Projected DOSitiOn. e V ment of the disk without the necessity for ha-vi The latch 4l comprises a sleeve 55 screwplacing on threaded at 56 on the upper end of a tube 51 desupfported pending within the upper portion of the mandrel 42, tube 51 having a sliding t within the mandrel bore and being longitudinally movable within the body. Downward movement of latch sleeve 55 and tube 51 relative to the body is resisted by a coil spring 58 conned between the body section 2| a rotatable sleeve 32 between body rings 32|, there being a pin 38 projecting from the body through a horizontally extending slot I0' in the sleeve. The construetion is best shown in Fig. 2 wherein the sleeve 32- has been shown, for purposes of illustration,

to be rotated substantieiiy in the direction upper end 0f mandrel 42 and the bottom of of. the srrow,to more eieeriy illustrate its slotted Sleeve t5- formation. In reality, when the cleaner is lowi- Latch Sleeve 55 iS l0rl8itlldn8lly SlOtted fOr a eredin the weil, the sleeve wiil be rotated to the Short distance downwardly from its upper end position of Fig. c, es wiu be explained. The disk to form. radially expansible detente 55e having on carrier member 3s is inserted within and witiitheir upper ends projections Ssfwbich are engagedrawn from the body through the sleeve slot I ible With an annular Shoulder 50 formed on the registering with body Slot 35a, In order to porlower end of tubular member 45. Detents 55a mit member 35 to be Withdrawn through Slot have sumcient clearance at 5| from the wall of after a cleaning operation with the disk breaking boi? Section 4,0 t0 permit radial expansion 0f member 45 projected up through member 35 in projections 59 to the extent of releasing shoulder the later dosoribed position of Fig 6, 1 provide 50 and member 45 for upward movement. as will presently appear. Upon upward movement of the spondingly shaped slot nza (Fig 1) 1n the body body relative to sleeve 55 from the positions of Fig. section 2 I, through which a pin (not shown) may 2 to Fig. 4, detent shoulders 52' come into engagebe inserted. within one of the openings ||3 in ment with annular surface 63 on shoulder 50, the the disk breaking member.. By means of the angularity-of

Surfaces

62 and 53 beine: such that inserted pin, the disk breaking member may be. the latch will retain the disk breaking member `until spring 50 will be compressed to the point at which lugs 53 come into engagement with the upper end of liner 5|.

Surfaces

52 and 53 may have any suitable angularity greater than the slip angle, though Iin practice an angle o f around 30 viewed in Fig. 2, to lock' member 35 in place, has been fcllnd Satisfactory. The-.angularity 0f surfaces `,54 on the detents 55a. and surfaces 55 shown`l in Fig, 6, which position is determined by on member 46 preferably will be somewhat greatthe engagement of pin 38 with the end of the er, for instance around 60,in order that there will be no undue resistance to movement of member 45 from the projected position of Fig. -6 back into sufficiently to enable member 35-to^be withdrawn through slot tl, and another disk carrying meri.-

, The lower end of section 2| is threadably conf) nected at 39 with body section 40, theiatter in retained engagement by the latches in'Fig. 2, tur being connected by screwthreads 4| with as the body is lowered to reset the disk breaking the reduced diameter 'lower tubular section 42 YJmember' in the manner hereinafter described.

The sleeve structures comprises a tube 55 care rying a pair of longitudinally spaced packers generally indicated at 51 and 58, which may be of any suitable type and construction capable by mandrel section 42 is-closed by a screwthre'aded member- 43, the-bottom of which 'is tapered 'as at 44 to facilitate 'passing any obstructionsthat` engagementwith the casing C, of confining bemight .be encountered within the casing while the tween them an annular' space 59 through which cleaner is being` lowered. suction is applied to the casing perforations P -The low pressure chamber opening mech nism; opposite the space when the charge receiving generally indicated at 45, comprises a disk b` chamber is opened, as hereinafter described. As

against substantial vertical movement in thecasing during operation of the cleaner, as willfully appear later. Nuts 11 and 1a having rounded end surfaces 11b are threaded on the upper and lower ends of tube 68.

As best illustrated in the cross sectional view of Fig. l1, opposite sides of the mandrel portion 42 of the body are ilattened at 18 to form with sleeve 68, longitudinal by-pass passages 19 exered with the disk breaking member 46 in untending the -full length of the sleeve. Between passages 19, the mandrel 42 has a fairly snug and substantially fluid-tight sliding iit with sleeve 86. Latch tube 51 is connected with sleeve 86 by means of a .transverse pin 80, see Fig. 14, extending through the lower end oi the tube and terminating in the' sleeve. Relative longitudinal movement between the body and sleeve assembly, including with the latter the latch tube 51, occurs within the limits of engagement of nut 11a on the upper end of sleeve 88 with the lower end of body portion 48, see Fig. 9, and the engagement of nut 11 on the 'bottom of the sleeve withthe mandrel nut 43, as shown in Fig. 10. During such relative longitudinal movement between the mandrel and sleeve, pin 88 travels longitudinally within slots 8| in the mandrel. However, in order to preclude the possibility of the pin becoming sheared While the apparatus is going into or coming out of the well, slots 8l are extended somewhat beyond the limiting positions of the pin 88,'see Fig. 14, when the sleeve andmandrel are in their extreme relative positions corresponding to Figs. 2 and 7.

The mandrel 42 is chamfered at 82 and 83 at both the upper and lower extremities of ilattened surfaces 18 so that in the uppermost and lowermost positions of the mandrel relative to the sleeve 68, these by-pass. passages will remain in open communication with the interior of the cas- 7 ing through the

openings

84 and 85, se`e Figs. 9

and 10, formed by the

chamfers

82 and 83. At this point it may be particularly noted that in all operating positions of the cleaner, and throughout the range of relative movement between the body B and sleeve assembly S, the by-pass passages remain open. The purpose of these passages is of course to provide for the lay-passing of well liquid past the

packers

61 and 88 as the cleaner is lowered or raised in the well and to eliminate iluid resistance to such movements.

Opposite sidesof the intermediate portion of.

sleeve 68 between

packers

61 and 68 have longitudinal slots 88, the edges of which are beveled asl indicated by the surface at 81, see Figs. 3 and 11. 'I'hrough these slots, suction is communicated to the surrounding space 89 between the packers by way of the mandrel bore 88 and a series of mandrel ports 89, see Fig. 11, registering with the sleeve slots 86. Some of the uppermost ports 89 may be in registration with slots 86 when the mandrel is in its lowermost position relative to the sleeve, see Fig. 3, but when the mandrel has been raised to its uppermost position, substantially as illustrated in Fig. 7, all the ports 89 are vbrought to register with the slots 86.l Pin 80 prevents -relative rotation between the mandrel and sleeve, and keeps slots 88 and-ports 89 in longitudinal alinement.

In operation, the cleaner is lowered into the` well with the parts in the position shown in Figs.

2 and 3, the disk breaking member 48 having been inserted within the latch 41 but remaining in an uncocked or out of retracted position. The sleeve assembly S -is forced downwardly through the casing against the resistance of

packers

61 and 68, by the engagement of the intermediate body section 40 with nut 11b on the upper end of sleeve 66. During downward movement of the cleaner through the well liquid standing n casing C, the liquid is by-pa'ssed upwardly past the packers through the open passages T9. The apparatus is lowered in the well until space 69 between the .packers is brought opposite the particular portion of the perforated casing to be cleaned.

By reason of the fact that the cleaner is lowsubstantial lost motion between the parts before the member can bemoved to a retracted or cocked position, the possibility of the low pressure chamber opening mechanism being accidentally tripped while the cleaner is being lowered, is practically precluded. This will be seen upon consideration of the fact that if obstructions are encountered that would tend to temporarily hold up and then cause the sleeve and latch assembly to suddenly drop relative to the body, still such movement would not trip the disk breaking member; 'Ihis is true because, first, of the resistance of spring 58 to downward movement of the latch sleeve to the trip position, and second,'due to the lost motion afforded by the necessity for the detent 59 to move downward from the position of Fig. 2 to the point of engagement with shoulder 80, and member 46 to be subsequently pulled down to the point where lugs 53 engage the upper end of liner 5I, before the disk breaking member can be cockedand the latch released to project it against the disk 31.

After theapparatus has been lowered to proper position for the cleaning operation, the body B is raised to progressively elevate shoulder 80 into engagement with the detents 59 and to raise liner 5I into engagement with lugs 53, as shown in Fig. 4. Upon continued upward movement of the body, the latch is released from the disk breaking member and the latter is projected upwardly, by the expansive force of' spring 50, to engage and break the disk 31, see Fig. 6. Due to the suddenness of the disk breaking operation,

`the low pressure chamber I la is instantly placed to be drawn into the low pressure chamber through the full registering slots 88 and ports 51 and the breaking member 4 6.

As previously mentioned, if for any reason the member'46 fails to break the disk inA one operadered end of vmember 48'into the latch sleeve 55,

thus resetting the disk breaking mechanism for another operation as above described.l Immedi ately upon breaking the disk 31, the charge is drawn upwardly into the chamber lla, unseat- Aing valve 24, until a pressure balance exists.

.Thereupon the ball valve 24 seats, and the cleaning `operation is completed so thatthe cleaner -89, and thence upwardly through the latch tube 'may now be pulled fromthe well with the charge trappedin' chamber la. In elevating the cleaner,

l the sleeve S is pulled upwardly with the body by the engagement of nut 11 on the bottom of the sleeve by the mandrel nut 43, by-pass passages 19 remaining open all the while to obviate any resistance to removal by the presence lof the hydrostatic column of liquid in the well.

In Figs. 15`to 21, I show a variational form of the invention similar in its general construction and mode of operation to the previously described form, but differing in the construction of the mandrel and in additional provisions for rendering the apparatus proof against accidental tripping while the cleaner is being lowered in the well. In the views showing the variational form of the invention, parts similar to corresponding parts in the first described form are designated by the same numerals with primes added.

Referring to Figs. 15 to 18, the mandrel M', is shown to include an inner tube 42' and an outer sleeve having a fluid-tight fit with the tube 42 except where opposite surfaces 18' of the latter have been flattened to form by-pass passages 9| as in the first described form. Sleeve 00 is confined between the lower end of body section 40' (see Fig. 17) and nut 43 (see Fig. 18) on the lower end of the mandrel, the sleeve terminating within annular recesses 92 and 93 and being locked .by set screws 94.

Openings

95 and 96 are formed in the upper and lower ends of the sleeve 90 and mandrel 42 at the ends of mandrel surfaces 18 in order to provide constantly open communications between the ends of by-pass passages 9| and the'interior of the casing.

In this form of the invention, the by-pass passages are contained entirely within the mandrel itself, as distinguished from the first-described form in which the corresponding passages are directly between the packer carrying sleeve and the mandrel. Sleeve 90 has'a freely sliding fit with sleeve 66', the necessity of providing a fluidtight t between the sleeves not being as important as the desirability for a close t between the mandrel and sleeve in the rst described form, due to the fact that with the by-pass passages conned within the sleeve part of the mandrel, a substantially greater sealing surface contact is maintained between the relatively moving parts.

Ports 98 drilled through the sleeve 90 and mandrel 42', are adapted to be brought into registration with longitudinally extending slots 99 formed in opposite sides of the sleeve 66', when the mandrel is raised to uppermost position determined by the engagement of nut 43' with nut |00 on the lower end of the sleeve. Astirrup |02, best illustrated in Fig. 21, is connected to the lower end of latch sleeve 55 by a collar |03 attached to the top of the stirrup and threaded into the lower end of the latch sleeve. Stirrup f |02 depends within the mandrel section 42' of the body, and has intermediate its ends a bridge portion |02a adapted to be brought into .engagement with the pin |04, see Fig. 19, which extends through the lower opening |0217 of the stirrup, mandrel slots 6|', and terminates in the sleeve 56. As in the described form, a coil spring is placed within body section 40' between latch sleeve 55' and the upper end of the mandrel section 42'.

In operation, starting with the parts in the positions shown in Figs. l and 16, upward movement of the body irst raises the stirrup 02 to the point where pin |04 is brought into engagement with the bottom of the stirrup at the lower end of opening |02b. It will be noted that until pin 04 engages the lower end of the stirrup, no relative movement occurs between the latch mechanism and the disk breaking member, in distinction to the iirst. described form wherein, by reason of the latch being integrally connected with the sleeve, the latch starts to move relatively toward the lower end of the disk breaking member at the start of upward movement of the body. Thus in this variational form, I have in effect provided for additional lost motion in the disk breaking member operating mechanism, the extent of lost motion being the l'ength of opening |02b in the stirrup, or the distance which pin |04 must move relatively before the latch sleeve 55 starts its downward relative movement within the body to cock the disk breaking member.

Upon further upward movement of the body and mandrel, stirrup |02 is first raised t0 the point where pin |04 is engaged at they lower end of opening |02b. With latch sleeve 55 held against further upward movement, member 46 is raised to the point of engagement between detents-59' and shoulder 60. Subsequent upward travel of the body cocks the disk breaking member and releases it to be projected against the disk, all in the manner previously described.

By reason of the additional lost motion afforded by the pin and slot connection 04, |02b, between the latch and sleeve 66', further assurance is had against accidental tripping of the disk breaking member while theeleaner is being lowered into the well. Thus, if for any reason the sleeve assembly tends to suddenly drop on the mandrel, pin |04 `must lower to the point of engagement with the bottom Vof the stirrup before vthe latch can move relatively to the breaking member to move the latter toward cocked position. In order to provide a yielding resistance to upward movement of the body relative to the stirrup after the latter has been raised to the point of engagement with pin 04, the length, longitudinally of the body, of spring 58' preferably is adjusted so that the lower end of sleeve 55 will come into engagement with the spring at substantially the time when the lower end of the stirrup engages pin |04.

In Fig. 15, I have shown the inclined surfaces 64' of detents 59, and also surface 65' on shoulder 60', to have a different angularity than the corresponding

surfaces

64 and 65 oi the iirst described form, in order to increase the resistance to reengagement of shoulder 60 within the latch after the member 46' has been projected against the disk 3| In this last form, surfaces 64 and 65 may have an angularity in the neighborhood of 45, or of any other suitable value that will increase'the resistance of resetting to the extent that if member 46' fails to break the disk, shoulder 60' will be supported suiiiciently on the detent surfaces 64 to enable the body and disk 31 to be suddenly dropped down against the upper end of member '46 to break the disk, without necessarily having to force the breaking member into retained engagement by the latch.

I claim:

1. In a well cleaning device, a body forming a low pressure chamber, normally closed means adapted to be opened to admit well liquid to said chamber, a member movable relative'to said body from retracted to projected position to open the rst mentioned means, means for releasably holding said member in retracted position, and a suspension means on which said body is lowered into the well, said member being movable from non-retracted position to retracted position and into retained but releasable engagement with said holding means after said body has been lowered in the well.

2. In a well cleaning device, a body forming a low pressure chamber, normally closed means adapted to be opened to admit well liquid to said lowered in the well.

3. In a well cleaning device, a body forming` a low pressure chamber, normally closed means adapted to be opened to admit well liquid to said chamber, a member movable relative to said body from retracted to projected position to open the rst mentioned means, a suspension means on which said body is lowered into the well, and means independent of said suspension means for releasably holding said member in retracted position, said member being releasable from and reengageable with said holding means by raising and lowering said suspension means.

4. In a well cleaning device, a body forming a low pressure chamber, normally closed means adapted to be opened to admit well liquid to said chamber, a member movable vertically relative to said body from retracted to projected position to open the first mentioned means, a suspension means onz which said body is lowered into the \i7e:ll,1and means independent of said suspension means` for releasably holding said member in retractedposition, said member being releasable from and reengageable with said holding means by raising and lowering said body.

5. In a well cleaning device, a body forming a low pressure chamber,. normally closed means adapted to be opened to admit well liquid to said chamber, a member movable relative to said body from retracted to projected position to open the first mentioned means, yieldable means resisting movement of said member from projected to retracted position, means for releasably holding said member in retracted position, and a suspension means on which said body is lowered into the well, said member being movable from nonretracted position to retracted position and into retained but releasable engagement with said holding means after said body has been lowered in the well.

. 6. In a well cleaning device, the combinatin comprising, an apertured sleeve, means holding said sleeve in engagement with the well casing,

a body movable vertically relative-to said sleeve and containing a low pressure chamber, normally closed means adapted to be opened to admit well liquid through said sleeve to said chamber, a member movable relative to said body from retracted to projected position by virtue of upward movement of the body relative to the sleeve, to open said normally closed means, means associated with said sleeve for releasably holding said member in retracted position, and a suspension means on which said body and sleeve are lowered into the well, said member being movable with the body from non-retracted position into retained engagement with said holding means, upon downward movement of said body relative to said sleeve.

7. In a well cleaning device, the combination comprising, an apertured sleeve, means holding said sleeve in engagement with the well casing, a body movable vertically relative to said sleeve and containing a low pressure chamber, normally closed means adapted to be opened to admit well liquid through said sleeve to said chamber, a

y member movable relative to said body from retracted to projected position by virtue of upward movement of the body relative to the sleeve, to open said normally closed means, a spring latch connected to said sleeve for releasably holding said member in retracted position, and a suspension means on which said body and sleeve are lowered into the well, said member being movable with the body from non-retracted position to retracted position and into retained engagement with said latch, upon downward movement of said body relative to said sleeve.

8. In a well cleaning device, the combination comprising, an apertured sleeve, means holding said sleeve in engagement with the Well casing, a body movable vertically relative to said sleeve and containing a low pressure chamber, normally closed means adapted to be opened to admit well liquid through said sleeve to said chamber, a

member movable relative tov said body from retracted to projected position by virtue of upward movement of the body relative to the sleeve, to open said normally closed means, a latch movable vertically relative to said sleeve for releasably holding sald member in retracted position, means for limiting upward movement of the latch relative to the sleeve, and a suspension means on which said body and sleeve are lowered into the well, said member being releasable from said latch by upward movement of said body relative to said sleeve, and being returnable into engagement with said latch by reverse relative movement between said body and sleeve.

9. In a vwell cleaning device, the combination comprising, an apertured sleeve, means holding said sleeve in engagement with the well casing, a body movable vertically relative to said sleeve and containing a low pressure chamber, normally closed means adapted to be opened to admit well liquid through said sleeve to said chamber, a member movable relative to said body from retracted to projected position by virtue of upward movement of the body relative to the sleeve, to open said normally closed means, a latch movable vertically relative to said sleeve for releasably holding said member in retracted position, means for limiting upward movement of the latch relative to the sleeve, and a suspension means on which said body and sleeve are lowered into the well, said member being releasable from said latch by upward movement of said body relative to said sleeve, and being returnable into engagement with said latch by reverse relative movement .between said body and sleeve, there being tracted position, and means for moving said 75 member from non-retracted position into retracted position while the device is lowered in the well.

11. In a well cleaning device, a body forming a low pressure chamber, a i'rangible element closing one end of said chamber, a member movable longitudinally within said bodyvfrom retracted to projected position to engage and break said element, and a latch engaging said member to hold it in retracted position, and means for moving said member from `non-retracted position into retracted position while the device is lowered in the well, said meniber being engageable with and releasable from said latch by straight longitudinal movement relative thereto.

12. In a well cleaning device, a body forming a low pressure chamber, a i'rangible element closing one end of said chamber, a tubular member movable longitudinally within said body from retracted to projected position to engage and break said element, said member being adapted'- to pass well iluid into said chamber when said element is broken, and a latch comprising a yieldable element engaging said member to hold it in retractedzposition, and means for moving said member from non-retracted position into retracted position while the device is lowered in the well.

13. In a well cleaning device, a body forming a low pressure chamber, a frangible element closing one end of said chamber, a member movable longitudinally within said body from retracted to Aprojected position to engage and break said element, yieldable means resisting movement of said member from projected to retracted position, and

a latch engaging saidmember to hold it in retracted position, and means for moving said member from non-retracted position into retracted position while the device is lowered in the well.

14. In a well cleaning device, a body forming a low pressure chamber, a frangible element closing one end of said chamber, a member inovable longitudinally within said body from retracted to projected position to engage and break said element, a shoulder on said member, and a latch engaging said member to hold it in retracted position and comprising a detent engageable with and releasable from said shoulder by straight relative longitudinal movement between said member and detent.

15. In a well cleaning-device, a body forming a low pressure chamber, a Irangible element closing one end of said chamber, a member movable longitudinally within said body from retracted to projected position to engage and break said element, a latch engaging said member to hold it in retracted position, and means for moving said member from non-retracted position into retracted position while the device is lowered in the well, yieldable means resisting relative movement between said latch and the body, and yieldable means resisting movement of said member from projected to retracted position.

16. In a well cleaning device, the combination comprising, an apertured sleeve, meansholding said sleeve in' engagement with the well casing, a'

body movable vertically relative to said sleeve and containing a low pressure chamber, normally closed means adapted to be opened to -admit well liquid through said sleeve to said chamber, and means for opening the last mentioned means by virtue of relative longitudinal movement between said body and sleeve, there being a by-pass passage between the body and sleeve that remains 75 open throughout'said relative movement.

17. -In a well cleaning device, the combination comprising, an apertured sleeve,A means holding4 said sleeve in engagement with the well casing, a body movable vertically relative to said sleeve and containing a low pressure chamber,normally closed means adapted to be opened to admit well liquid through said sleeve to said chamber, means for opening saidJ normally closed means, the

last mentioned means comprising a latch and a closure opening member movable into and out oi retained engagement with said latch by relative movement of said body and sleeve.

18. In a well cleaning device, albody forming a low pressure chamber, normally closed means adapted to be opened to admit well liquid to said chamber, a member movable relative to said body from 'a cocked position to a projected position to open said means, yieldable means resisting movement of said member into Vcocked position, al

-open said means, yieldable means -resistin'g movement of said member into cocked position, a latch for releasably holding said member in cocked position, and means operable by vertical movement of said body for bringing said'latch into holding engagement with said member after the deviceis lowered in a well with said member in uncooked position. l

o2i). In a well cleaning device, an apertured sleeve, spaced packers carried on said sleeve and adapted to engage the well casing, a body movable vertically relative to said sleeve and forming a lowpressure chamber, normally closed means adapted to be opened to admit well liquid through said sleeve into said chamber, a member movable relative to said body from a cocked position to a projected position to open jsaid means, yieldable means resisting movement of said memberinto cockedposition, a latch for releasably holding said member in .cocked position, said latch being operable by relative movement between said body and sleeve after the device has been lowered in the well, to cock said member.

' 21. In a well cleaning device, an apertured sleeve, spaced packers carried on said sleeve and adapted to engage the well casing, a body movable vertically relative'to. said sleeve and forming a low pressure chamber, normally closed means adapted to be opened to admit well liquid through said sleeve into said chamber, a member movable relative to said body from a cocked position to a projected position to open said means, yieldable means resisting movement of said member into cocked position, a latch for releaslatch being operable by relative movement between said body and sleeve after the device has been lowered in the well, to cock said member,

Iand the latch being engageable with said' memably holding said member in cocked position, said tion, said latch being operable by relative movement between said body and sleeve after the device has been lowered in the Well, to cock said member, and yieldable means resisting relative vertical movement between said latch and the body.

23. In a well cleaning device, an apertured sleeve, spaced packers carried on said sleeve and adapted to engage the well casing, a body movable vertically relative to said sleeve and forming a low pressure chamber, normally closed means adapted to be opened to admit well liquid through said sleeve into said chamber, a member movable relative to said body from a cocked position to a projected position to open said means, yieldable means resisting movement of said member into cocked position, a latch for releasably holding said member in cocked position, said latch being operable by relative movement between said body and sleeve after the device has been lowered in the Well, to cock said member, and the latch being engageable with said member when the latter is in uncocked position' and then having substantial vertical movement relative thereto before acting to cock said member, and yieldable means resisting relative vertical movement between said latch and the body.

JAMES J. SANTIAGO.