US2893690A

US2893690A - Formation sampler device

Info

Publication number: US2893690A
Application number: US434474A
Authority: US
Inventors: Lawrence S Chambers
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-06-04
Filing date: 1954-06-04
Publication date: 1959-07-07
Anticipated expiration: 1976-07-07

Description

y 4 sheets-sheet y1' July 7, 1959 L. s. CHAMBERS FORMATION SAMPLER DEVICE 2 0 I0 Afl 2 E 1H Mil l.. s cHAMBr-:RS FORMATION SAMPLR DEVICE July 7, .1959

Filed June 4, 1954 INVENToR.

A'rTy.

July 7, 1959 s. CHAMBERS FORMATION SAMPLER DEVICE 4 Sheets-Sheet 5 Filed .JuneV 4. 1954 INVENToR. Lani/gwn 5f (1m/1eme ./lTToR/vay 1United Sttes Patient FORMATION SAMPLER DEVICE Lawrence S. Chambers, Pasadena, Calif. Application June 4, 1954, Serial No. 434,474 17 Claims. (Cl. Z55-1.4)

This invention relates to a sampler for recovering bit lcuttings .produced during oil well drilling operations to 'determine the Vnature of the formation being penetrated bythe drill bit` :In ,present drilling practice it is customary to collect samples of the formations being penetrated from the rm-ud returns at the surfface of the ground. These samples are adequate for some purposes; but are usually mixed with material that caves from the side of the hole at shallower depths. Also, the cuttings are diluted with a large amount of rotary mud fused for circulation and to a consideralble extent are washed clean of any oil showings that may have been originally present. If the formation being penetrated is of a clayey nature, a large portion of the cuttings will be softened by water contained in the drilling fluid and may be reduced to soft mud. Also, in the tn'p up the hole the cuttings are subject to additional grinding by the action of the drill pipe rotating against the wall of the hole.

In many cases, a reliable sample of cuttings 'from the bottom of the well bore will be suiiicient to determine the nature ofthe formation being penetratedand make .unnecessary the taking of a conventional core for this purpose. Also, in some areas it is common practice to core on dlilling breaks, i.e., when rate of penetration of vthe bit increases, since a more rapid drilling rate usually indicates the presence of a sand which may be gas or oil bearing. If the sand penetrated contains oil or tgas, it may lbe desirable to core this formation and do additional testing. If positive data were available to indicate that the sand was water bearing and contained no gas or oil showings or that the drilling break was due to fractured shale or some other formation characteristic which permitted the accelerated penetration of the bit, a core would not be needed. With the device orf this invention, a sample of the bit cuttings with the drilling mud is taken from the bottom of the hole and returned to the surface without contamination with additional fluid and without requiring the substitution of a conventional core barrel for the drilling bit.

The samples obtained by my device are adequate for micropaleontological examination and usually indicate the presence of oil or gas, and in this respect may take the place of a conventional core. However, since coring may be desired for additional reasons or to supplement the information obtained from the sample taken by my device, it is an additional and important advantage of the invention tool to indicate when coring is advisable, and to eliminate unnecessary coring with the loss of time and expense entailed therein.

An object of my invention is to devise a formation sampler for the recovery of bit cuttings from the bottom of the bore of an oil |well.

Another object is to provide a sampler device of the foregoing type which is adapted to be inserted in a drill pipe and fused in conjunction with conventional rotary drilling bits.

Chert formations suchas are produced in certain localities are very diicult to recover with a conventional core barrel; also, lost circulation is common during coring and also during drilling so that no cuttings are recovered at the surface. The device ofmy invention solves a problem of formation sampling in such localities.

6 differential pump pressure is applied to the tool.

It is still another object of the invention to provide a tool which furnishes a quick check of the formations being penetrated which may appear to be oil bearing.

` The foregoing objects and advantages are accomplished 5l vin my invention by the provision of a sampler tool for retrieving bit cuttings, which is adapted to be inserted in the dn'll pipe at the surface and dropped or pumped down through the drill pipe to a position adjacent the circulation ports in the drilling bit located at the bottom of the Ybore hole. The invention tool comprises a sample receiving chamber, an inlet passageway to permit ow ofliquid containing lbit cuttings which pass through the circulation ports of a bit into said chamber, and a valve in such passageway. The valve is preferably in the form of a frangible tube or diaphragm which is ruptured by means of an explosive charge which is tired when the device is positioned to receive ,the cuttings passing through the circulation ports,

1n a preferred embodiment, when using this frangible diaphragm, I also inlude a valve, preferably in vthe form of -a check valve positioned in the passageway between the circulation ports and the frangible diaphragm, Rupturing the frangble tube or diaphragm permits cuttings from outside the drill pipe, along with drilling fluid, ,to

pass into the sample receiving chamber `through the rup.-

tured diaphragm. This chamber, prior to the introduction of bit cuttings, generally contains air at atmospheri pressure. A packing device is positioned on the tool to,

aid in pumping the Vtool down the drill pipe to Yits position adjacent the drill fbit at the bottom of the drill pipe and to prevent mud circulation or passage thereof downward around the tool, i.e., between the tool and drill pipe, while the sample of bit cuttings is being obtained.

The tool is inserted into the drill pipe and may be pumped to the bottom `adjacent the circulation ports of the bit. The packer acts ,as a valve, thus shutting otf mudcirculation. The mud the arrival of the tool at its bottom station.

A by-pass channel extends Within the tool above and below the packing device, and a by-pass valve is posi-k tioned in this channel. Entry of mud and cuttings into the sample chamber urges a freely floating piston positioned therein upwardly against a rod, the upward movement of which opens the valve in said channel and allows fluid and mud circulation through this channel and through ports outwardly to the space between the tool and the drill pipe below the packer, and downwardly in this space and through the ports in the drilling bit. With the by-pass valve open, relatively free circulation may be established by the mud pumps, thus giving a surface indication that the tool has performed its function. An additional means is provided for opening or holding open the by-pass valve in said channel when the sampling tool is being withdrawn from the drill pipe after a sample of bit cuttings has been captured. Such means is in the form of a spear connected to the valve in the channel, the spear being engaged by an overshot connected to a Wire line. In this manner the tool may be Withdrawn readily from the drill pipe without swabbing mud from the drill pipe.

- A spring loaded safety valve, normally closed, is also provided in communication with said by-pass channel. The latter valve can be set to open when a pre-selected Opening of the safety valve allows circulation of lluid through said channel and through the by-pass valve, through the outlet ports in the tool, around the tool and out the ports in the drill bit. When the tool lands on bottom, and the mud pressure rises as stated above, thev safety valve prev vents excessive pressure increases which may damage theV tool and the surface equipment,

pump pressure rises indicating This invention will be more fully understood from the description below of a preferred embodiment of my invention'taken iii connection with the accompanying drawings, wherein: l

Fig. 1 is anV assembly view generally showing the bit cuttings retrieverfor sampler device of the invention;

Fig. 2`is a section of the drill pipe and the upper portion of the sampler shown in a position prior to receipt of a sample of drilling mud and bit cuttings;

Fig. 3 is a view similar to Fig. v2, showing the'upper portion of the sampler tool in a position during receipt of bit cuttings in the sample chamber;

Fig. 4 is a view similar to Fig. 2, showing the lower portion of the sampler tool of Fig. 2;

Fig. 5` is a View showing the lower portion of the sampler tool of Fig. 3;

Fig. 6 is a section taken on line 6--6 of Fig. 3, looking in the direction of the arrows;

Fig. 7 is a section taken on line 7-7 of Fig. 3, looking in the directionof the arrows;

Fig. 8 is a view similar to Fig. 5, showing the lower portion of my tool with the lower valve closed, following receipt of drilling mud and bit cuttings in the sample chamber of the device;

Fig. 9 isa section showing a modification of the timing device and diaphragm rupturing mechanism of the invention sampler;

Fig'. l0 is aview similar to Fig. 9 following actuation of the timer device; and

Fig. 11 is a section taken on line 11-11 of Fig.l 9, looking in the direction of the arrows.

Referring to the drawings, the drill pipe 12 positioned in well bore' 13 has a collar 15 at the lower end thereof which is threadably engaged asfat 14 to a conventional rotaryY drill bit 16, illustrated as a fish tail drag bit. The drill bit 16 has a pluralityA of circulation ports 17 for circulating mud and uidfrom the interior to the exterior of the drillv pipe, or in the reverse direction. Any other rotary or impact bit containing circulation ports, eg., a rock bit, may be used. The sampler device 18 of the invention is introduced at the drilling floor into the drill pipe 12 'after removal of the kelly, the drill pipe being suspended in the slips of they rotary table with the drill bit suspended above the bottom of the hole. The kelly is replaced'and the'sampler tool is circulated to bottom by pumping mud into thedrill pipe. During this operation the bit Vis lowered to within 1 or 2 feet of bottom.

Arrivall of the sampler tool at the bottom, where it seats adjacent to orjin contact with the'drill bit, is signalled by the rise in mud pump pressure due to blocking of the drill pipe by the packer 86, as will be described more fully hereinbelow.

The sampler Vtool 18vis composed of a hollow cylindrical fittingrZi open at its lower end and Vcommunicating with ports17 in the drill bit when positioned at the'bottorn of the` drill pipe. Fitting 20k has a series of circumferential ports22 bringing the interior of the fitting into communicationjf with the annular space 23. between the fitting and drill collar 15, which as is conventional connects the bit and the drill pipe. At the upper end of fitting 20 is aconical valve seat 24 on which is normally seated in closed position, as seenin Fig. 4, a conical check valver26'by means of a compression spring 28.en

circling the valve' stem 30 and positioned between anut 32 fixed ,atA the end of the valve stem and a guide bracket 34 for the stem 30, the guide bracket being connected to the wall of said fitting.

The lower end of a cylinder 36 is threaded onto the upper end of fitting 20, the end of the cylinder abutting an, exterior flange 38 on the outer periphery of fitting 20. Thenupper portion of the cylinder 36 is threadably connected to the lower portionof another fitting 40, with the upper end of cylinder 36 abutting against an exterior peripheral fiange 41-on the fitting 40. This fitting has a central bore,42..communicating with

enlarged bores

43 and 44 at the top and bottom, respectively, of the fitthreadably secured to internal threads in bore 44. The upper flanged end 47 of a tubular frangible diaphragm 48 having a closed cup-shaped bottom is clamped between the upper end of sleeve 4S andfan internal horizontal shoulder 50. forming the upper end of bore 44in fitting 40. The tube 48 extends downwardly in contact with the inner surface ofsleeve 45 and depends a substantial distance below sleeve 45.1'nto the chamber 52 formed between fittings 2i) and 40. The frangible tubular diaphragm 48 separates the chamberY 52 forming the interior of the cylinder 36, from the bore 43.

Positioned within the tube 48 is a cartridge of explosive 54 carrying a cap and insulated

electrical conductorv wires

56 and 57. Wire 56 passes upwardly through a bore 58 in a depending narrow neck 60 of a case 62.130-, sitioned above fitting 40, the 'depending neck 60 being threadably engaged within'an inwardly extending bracket 64 connected to the upper end of fitting 40. Wire 57 is grounded at 65, and the wire 56 Vis connected to batteries 66 which are connected by wire 67- to a conventional clock mechanism 68.

Screwed 'onto the top portion of fitting 40 with its lower end abutting the upper surface of flange 41 of fitting 40 is a cylinder 70,' the upper end of which is screwed onto a cylindrical block 72. A freely sliding piston 74V making a lsealand sliding fit with the walls of cylinder 70 is positioned in chamber 76 above the top of the case 62 and below block 72. Chamber 76 4extending between the frangible tube 48 and block 72 is a low pressure air chamber, for example, atmospheric pressure, in which the'sample of bit cuttings vis collected after Arupture of the tube 4S, as described more fully hereinafter. Block 72 has a narrow bore 77 therein communicating with a pocket in which is positioned a ball check valve 78 comprising a bail l79 and spring 80 normally'maintaining the valve closed Withthe ball seated to close bore 77. This valve serves toY equalize the air pressure in chamber 76 above the piston 74 with the pressure in the space outside of the tool adjacent the drill pipe, while preventing entrance of fluid from the drill pipe,4 as will be described below.

Integrally connected to the top of block 72 is a cylindrical member comprising a narrow lower cylinder 82 and an upper cylinder 84 of larger diameter, the diameter of cylinder 84 being substantially equal to that of cylinder 70. Screwed onto cylinder 82 intermediate its upper and lower ends is a packing device or packer 86 in the form of a swab cup, the outer surface of which makes frictional contact with the drillv pipe. The cup has a plurality of curved, upwardly extending resilient fingers 87, the upper ends of which are in contact with the outer Wall of cylinder 82. Packing members of this type are well known in the art, typical devices of this nature being marketed by the Guiberson Corporation of Dallas, Texas. Cylinder 82 has aport 88 locatedfat the lower end thereof below packer S6, and upper cylinder 84v has aport 90 near the lower end thereof and anA upper port 92 .spaced above port 90, both of rports'9i) and 92,y

being positioned above the packer V86..

`Slidably disposed in a central bore 94Min block 72 andV extending upwardly into cylinder 8 2 and dOWIlWaIdly into chamber 7 6is a rodv 96 having screwedrto its lower end a rod member 97 having an exterior diameter greater ing nut' 100 provides a seal between the interior of cylinder 82 and the bore 94,1 particularly during movement` of 4the rod as described below. The` rodv 96y carries a ring 102 thereon whichv contacts the nut A10,0 to limit downwardrnovenientvof the rod.

l onne'cted to the upper end of rod 96 is a triangularly shaped foot 99. Foot 99 makes contact with the lower end 124 of a cylindrical valve housing 104 located within v valve seat 106 formed on a shoulder 109 at the bottom of cylinder 84 4and about the periphery of the bore 107 located in lower cylinder 82.V Housing 104 has an intermediate enlarged portion 108 having a ball check safety valve 110 therein comprising a ball 112 supported against its seat 114 formed by a shoulder 116 of the housing, by a spring 118 resting on the bottom 120 inside the enlarged portion 108. The enlarged portion 108 of the valve housing 104 is spaced from the inner wall of cylinder 84 to permit free movement of such housing relative to the cylinder 84. The upper end of valve housing 104 has a hollow cylindrical neck 122 communicating with the interior of the enlarged portion 108 which in turn communicates with the interior of the lower cylindrical portion 124 of the valve housing. A port 126 is formed in the neck 122 of housing 104.

A plug 128 `is screwed into the upper end of cylinder 84 and has a central bore 130 to receive for free movement therein a shaft 132 having a spear head 134 at its upper end, the shaft being attached at its lower end by suitable means to the closed upper end 136 of the neck 122 of the Valve housing 104. To the overshot head 134 may be connected an overshot grapple 138 as in conventional practice for purposes of lifting the tool out of the drill pipe.

To obtain a sample of bit cuttings, the tool 18 is operated as follows: The tool is assembled with atmospheric pressure in chamber 76, the piston 74 at its lowermost position and the timing mechanism 68 set for the estimated time required to pump the tool to the bottom of the well bore, plus an additional time, e.g., about minutes, for handling and drilling for a short period. Drilling is stopped and circulation is continued for a short period and then stopped. To insert the tool in the drill pipe at the surface, the drill pipe is set on slips and the kelly removed. The tool parts have, when the tool is introduced into the drill pipe, the positions as shown in Figs. 2 and 4. The tool is then dropped in the drill pipe and the kelly replaced. The mud pumps are then started and the drill pipe is: lowered so that the drilling bit is close to bottom, i.e., one `to three feet. The sampler tool is forced or circulated downward until it comes to rest in a position against drill bit 16, as shown in Figs. 2 and 4. Rotation of the drill pipe may continue while the tool is being pumped down. When the tool lands on bottom a sharp increase in pump pressure will be noted and the pump should be immediately shut olf. During the period of descent of the tool, valve 105 is maintained closed, i.e., on its seat 106, by the Weight of the valve housing 104, and shaft 132 and their associated parts, and spring 118 normally maintains the check valve 110 closed to prevent circulation through the lower portion 124 of housing 104, past valve 105 into cylinder 82 and beyond packer 86, thus enabling the iluid in the drill pipe above the tool to force the tool downward.

At the commencement of the descent of the tool, the pressure within chamber 52 and the sample chamber 76 is approximately atmospheric. Shortly after the start of the descent, the head of fluid in the drill pipe becomes suiiicient to overcome spring 28 to open valve 26 and permit the entry of fluid and clean circulating mud into chamber 52. The chamber 52 continues to receive circulating fluid during the initial portion of descent of the tool until sufficient pressure is built up by the iluid and ,compressed air in chamber 52 to cause the Valve 26 to 6 Y i l N' A close, the valve 26 being in closed position when the tool reaches its lowermost point of rest in the drill collar adjacent the drill bit 16. If, after the tool has reached bottom, the differential pressure across the packer, due to; pump pressure, exceeds a predetermined pressure difference, the ball check safety valve 110 opens. This occurs when the pressure on the downstream side of the packer 86 exerted through port 88 is sufficiently less than the pressure on the upstream side of the packer 86 exerted through

ports

92 and 126, to overcome the force of the spring 108 and cause the ball check valve 110 to unseat. This allows circulation of iluid through and past the tool by means of port 92, chamber 140 in cylinder 84, port 126, the interior of Valve housing 104, openings 103, chamber 142 in cylinder 82, and port 88, the pressure differential across the packerv 86 dropping to the value set by the spring bias of spring 118. Safety valve 110 opens under the application of excess circulating pressure and prevents the sudden stopping of circulation which would cause very high mud pressure to suddenly build up and damage the tool and surface equipment. After the tool reaches the bottom, restricted circulation may continue for a period by increasing the pressure suiciently to open the spring loaded by-pass valve 110.

The kelly is replaced, and with Very little and preferably no circulation of drilling mud, the drill is set on bottom and an additional foot or so of hole is drilled. At this point, the clock 68 having been set for a predetermined time suicient to permit the above operations to be performed, the clock acts to make contact between the detonating cap in the charge 54 and the batteries 66 and the charge is exploded, fracturing the tube or diaphragm 48 (see Fig. 5). Communication is now established between the interior of tube 48 and the chamber 52. The clean mud and fluid trapped in chamber 52 during descent of the tool passes first through tube 48, then through

bores

42 and 43 and passage 49 in fitting 40, and into chamber 76 which up to this time has had air at atmospheric pressure trapped therein. The consequent lowering of the pressure in chamber 52 causes the head of fluid in the annulus surrounding the drill pipe to open valve 26.

Formation fluid containing bit cuttings then passes. through ports 17 in the drill bit upward through the open. valve 26, chamber 52, tube 48 and into the chamber 761 where it is trapped, as indicated in Fig. 5. Substantially no mud from the drill pipe above the packer 86 may enter, because the seal at the packer prevents the hydrostatic head above the packer being exerted for thisA purpose. As the fluid and mud in chamber 76 rises into' contact with the free traveling piston 74, the piston risesf also until the top of the piston engages the rod member 97, and continued rise of the fluid and piston 74 in chamber 76 pushes member 97 and rod 96 upward along with valve housing 104, causing valve 10S to open. This allows circulation of lluid through

ports

90 and 92, chamber 140, open valve 105, chamber 142, and out port 88. Upward movement of the rod 96 continues until member 97 strikes block 72, as shown in Fig. 3. At this time the build-up of pressure in

chambers

52 and 76 causes valve 26 to close, as seen in Fig. 8, trapping the sample of bit cuttings within the tool. If desired, the drill pipe may continue to rotate during the sampling operation.

The tool bit 16 is then raised olf the bottom of the bore hole and the kelly removed. The tool and the sample trapped therein may then be withdrawn by introducing the grapple 138 of the overshot, which is lowered on a wire line from the surface until it engages the overshot head 134. Tension placed on the wire and shaft 132 elevates the entire sampler assembly and at the same time maintains the by-pass valve open to permit circula-Y tion of fluid through the tool and facilitate ascent there'- of, yand to allow pulling the sampler device without swabbing the drill pipe. The assembly is thus lifted through the mud in the drill Y regions of decreasing hydrostatic head, the pressure in pipe.' As the sample rises through' the tube 70 is vented through passage V77 vand valve 78.

The sampler tool containing'the trapped iiuid sample ofybit cuttings in chambers 52 andY 76is returned to the surface. The tool is opened and the sample examined.

While the upper portion of the sample material in chamber 76 may `contain a portionof clean rnud admitted to the lower chamber 52 during the initial phase of descent ofthe tool, this does, not interfere with examination 'of` the sampleco'f bit cuttings v,retrieved from the bottom of the well bore. The proportion of such, initially entering mud may amount to, say to 10% of `the captured sample of bit cuttings.

Alternatively, instead of immediately retrieving the tool following capture of the sample of bit cuttings, the sampling tool can remain in the drill collar and be recovered when the drill bit is pulled for replacement. In this manner a reliable sample of the formationbeing penetrated may be recovered as often as the drilling bit is changed with very little loss of rig time.

Figs. 9 and l0 show a modiication'of the means described above for rupturing the frangible tube. According to this modiiicationthe upper portion of cylinder 36 is screwed onto a cylindrical fitting 144, with the upper end of the cylinder abutting the bottom of an intermediate'iiange 146 on fitting 144. The fitting has a lower bore 148 and a larger upper bore 150fhaving a lower conical portion which communicates with bore 148 through a narrow intermediate bore 152. Clamped between the horizontal shoulder 154 formed at the upper end of bore 148 and a short sleeve 156 screwed into bore 148 is an annular flange 157 of a frangible tube or diaphragm 158 having a relatively short depending cupshaped portion 160.

Screwed into a central bore 162 in` an inwardly extending bracket 164 integrally connected to fitting 14d is a barrel 166 having a bore 168 therein in vertical axial alignment with bore 152 and tube 158. Threadably secured to and supported on the upper portion of barrel 166 is a cylindrical housing 169 having a bottom wall 170 and a cover 172 screwed into the upper end ofthe housing l 169. An explosive cartridge 174 carrying a bullet 176 at its lower end is suspended in the upper end of bore 168, and a tiring pin 178 is slidably supported in a central bore 180 in the bottom 170 of housing 169. The lower end of the ring pin isl maintained in spaced relationship to the cartridge 174 bysuitable means, eg., a spring 181.

A hammer 182 is suspended within housing 169 at a distance above firing pin 178 by means of a dog 184 on the end of a lever 186, the dog 184 normally resting in a mating notch 187 in the upper outer surface of the hammer. In a Central pocket 18S in the upper end of hammer 182 is positioned a compression spring 198. which urges the hammer downward, the lower end of thespring resting on the bottom of this pocket and the upper end of the spring being attached to a bracket 192 held in iixed position by a pin 193 mounted in the side walls of housing 169. The spring 190 is positioned about a vertical rod 191 connected to bracket 192, for maintaining the spring in proper alignment. Lever 186 is pivoted at 194 and is urged in a clockwise direction about the pivot point 194 .by a tension spring 1955 connected at one end 196 to lever 186 and iixed at the other endV to a stud 198 in the wall of housing 169. Theother end of lever 186 has a dog 200 thereon which is in continuous contact with the peripheral surface of a cam 202 which is rotated in a clockwise direction by a clock mechanism 204, the cam having a notch 206 therein.

In operation of this modification, the clock mechanism 204 is set prior to insertion of the tool in the drill pipe, and` when the tool is in operative position in the drill col-lar adjacent the bit 16, and the pre-set time interval for manipulation of the tool to place itin positionto receive a sample of bit cuttings has elapsed, cam 200 has rotated to a position where dog 200 kof lever 186 drops into notch 206, as seen in Fig. l0, causing the lever Thus, entry of th'emixture of uid and bit cuttings into aseaao.

8 to rotate clockwise throughrthe action of spring 195. This withdrawsA dog 184 from notch 187in hammer`182, causing spring 1910ft`o push the hammer 182 downward. The hammerthen strikes the tiring pin 178 urging it downwardfin bore 180 until the poin'tnof the Iiringpin strikesrthe explosive charge- 174, which then explodes and propelsthe bullet v17 6 downward through barrel 166, m

rupturingV the tube 158V and permitting iiuid containing bit cuttings to enter chamber `208 through tube 158, bores 152and 15 0and port 210 in itting 144. The function-` ing (of the sampler'modiiied as shown in Fig'. 9 is the same as described*` above, except for the specic construction of the frangiblevalve and the means for rupturing the valve diaphragm.

As'willbe understood by those skilled in the art, I

lmay replace thevcartridge 174 and bullet 176 by a suitable detonated shaped explosive `-charge so that the explosive jet punctures the diaphragm 158.

Instead of placing thel bottom of the sampling tool of the invention essentially in contact with-the drilling bit 16` as shown. in Figs. 4 and 5, I may insert in the drill collar any device conventionally used for centering and positioning tools inserted intothedrill pipes to be positionedv on the bit, as, for example,4 surveying devices,

so that the bottom of the tool is spacedifrom the drill` bit 16. Such devices are constructed to permit passage of fluid from the drill channels into the interior of the drill, and into thelower portion 20 of the tool.

After a sample of bit cuttings has been captured Within lmy Sampler device, it is not essential that circulation through the tool be establishedprior to lifting of they device` to` retrieve the sample, although a period of cir` culation is preferred at this time. Hence, if desired, the

piston 74 and rod 96 with its depending member 97 maylbe omitted and thebore 94 inV block 72 made solid.

chamber '76 will not cause valve 105 to open, and accordingly no circulation can take place while the tool remains on bottom, except through the spring loaded safety.

0 valve 110. y However, when the tool is raised by the wire line overshot, the valve 'is ylifted oi its seat 106.

and opened by` tension on shaft 132 to cause circulation through the tool duringthe ,tool retrieving operation.

WhileI have described a particular embodiment of my invention for, the purpose of illustration,` it shouldVA bevk understood that various vmodihications and adaptationsthereof may be made within the spirit Vof the invention as set forth in the appended claims.

I claim: Y

l. A bit cuttings 4retrieving device for oil wells, said device being adapted for insertion into a drill pipe, which comprises an upper air chamber, a lower chamber, a frangible closure separatingsaid upper and lower chambers, means for fracturingsaid frangible closure at a predetermined time, a valve at the bottom of said lower chamber, said valve permitting iiow of tluid and sample cuttings into said lower chamber, means to close said valve onV receipt of a sample in said chamber, a freely -sliding piston in said upper chamber, packing means connected to the outer lwall of said sampler tool and adapted to expand into contact with said drill pipe, to prevent circulation between said device and said drill pipe and past said device, a port in said Vdevice above said packing means anda port in said device below said packing means, a by-passconduit communicating with said ports,

a by-pass valve in said conduit permitting circulation past said packing means and through 'a portion of said device, and a rod connected to said by-pass valve and extending into said upper chamber, said .piston cooperating with o said rod for actuation'of said by-pass valve, said packing 'means by-pass conduit and by-pass valve being disposed above said upper chamber.v

2. A bit cuttings retriever for oil wells, said device being adaptedto be inserted into a drill pipe, which. comprises a case housing including therein amupper;

A 9 A closed chamber, a lower closed chamber, a frangible closure separating said upper and lower chambers, a traveling piston in said upper chamber, a check valve in said upper chamber to permit uid to escape from said chamber when the external pressure is less than the pressure in said upper chamber, packing means disposed about said housing above said upper chamber, said packing means preventing circulation between said device and said drill pipe, a first port in said housing between said packing means and said upper chamber, a by-pass conduit in said housing, a normally closed by-pass valve in said conduit, a second port in said housing above said by-pass valve and said packing means, said by-pass conduit communicating with said ports, a slidable rod connected to said by-pass valve and extending into said upper chamber above said piston, said rod being actuated through contact thereof by said piston to open said bypass valve and permit circulation of uid through said ports -and said conduit past said packing means, a norl mally closed spring-biased valve at the bottom of said l lower chamber, said valve opening to permit flow of fluid and sample cuttings into said lower chamber, andl closing on receipt of a sample in said chamber, and means for rupturing said frangible closure at a predetermined time, whereby uid and bit cuttings from a well formation pass through said spring-biased valve and said lower chamber into said upper chamber to displace said traveling piston upwardly into contact with said rod for actuation of said by-pass valve.

3.. A bit cuttings retriever foroil wells, said device being adapted to be inserted into a drill pipe, which comprises a main case housing including therein an upper closed chamber, a lower closed chamber, a frangible Aclrtuilllfa,separat.ine said. ,upper and lower chambers, a traveling piston in said upper'clia'mber, `a` 'check valve vin said upper chamber lto permit iiuid to escape from said chamber when the external pressure is less than the pressure in said upper chamber, a bypass conduit in said main housing above said upper chamber, packing means disposed about said bypass conduit, said packing means preventing circulation between said device and said drill pipe, arst port in said main housing between said packing means and said upper chamber, a movable valve housing within said main housing and positioned above said packing means, a pressure valve, in said valve housing normallyA closed and adapted to open on the imposition of a predetermined pressure, the lower end of said valve housing communicating with said by-pass conduit, a second portin said valve housing above said pressure valve, -a shoulder in said main housing, the lower end of said valve housing cooperating with said shoulder to form a normally closed by-pass valve, a third port in said main housing above said bypass valve, said by-pass conduit communicating with said rst, second and third ports, a slidable rod connected to said valve housing and extending into said upper chamber above said piston, said rod being actuated through contact thereof by said piston l to movel said valve housing upward and open said by-pass valver and permit circulation of fluid through said rst and third ports and said by-pass conduit past said packing means, a normally closed spring-biased valve at the bottom of said lower chamber, said valve lopening to permit flow of Huid and sample cuttings into said lower chamber, and closing on receipt of'a sample in said chamber, and means forl rupturing said frangible closure at a predetermined n'mefwherebyiiuid and bit cuttings from a well formation pass through said spring-biased valve and said lower Y l chamber into said upper chamber to displace said traveling piston upwardly into contact with said rod for vactuation of said by-pass valve.

4. A bit cuttings retriever for oil wells, said device prisesV a case housing including therein an upper closedchamber, alower closed chambena .frangible losure separating said upper and lower chambers, pack- Y being adapted to be inserted into a drill pipe, which comassenso ing meansldisposed about said housing above said upper chamber, saidpacking means preventing circulation between said device. and said drill pipe, a by-pass conduit'v t permitting circulation from one side of said packing means to the other side thereof, a first port in said main housing between said packing means -and said upper chamber, a check valve in said upper chamber to permit iiuid to escape from said chamber Whnzthe external pressure is less than the pressure in said upper chamber, a movable valve housing within said main housing and positioned above said packing means, a pressure valve in said valve housing normally closed and adapted to'o'pen on the imposition of a predetermined pressure, the lower end of `said valve housing communicating with said bypass conduit, a second port in said valve housing above said pressure valve, a shoulder in said main housing, the lower end of said valve housing cooperating kwith said shoulder, l to form a normally closed by-pass valve for said by-pass conduit, a third port in said main housing above said bypass valve, said by-pass conduit communicating with said rst, second and third ports, a slidable rod connected to the upper end .of said Valve housing and extending exteriorly of said housing, whereby said by-pass valve is opened when said rod is urged upwardly to permit circulation of fluid through said first and third ports and said by-pass conduit past said packing means, a normally closed spring-biased valve -at the bottom of said lower chamber, said valve opening to permit flow of Huid and sample cuttings into said lower chamber, and closing on receipt of a sample in said chamber, and means for rupturing said frangible closure Aat a predetermined time whereby fluid and bit cuttings from a well formation pass through said spring-biased valve and said lower chamber into said upper chamber.

' 5.- A bit. cuttings retrieving device for oil wells, `said device being adap-ted to be inserted into a 4dillpipe hav-" ing a drill bit containing circulation ports and the device circulated to the bottom of said drill pipe adjacent said ports, which comprises an elongated main case housing including therein a lower closed chamber, a normally closed spring-biased valve at the bottom of said housing and said lower chamber, said valve opening to permit flow of uid and sample cuttings into said lower chamber, and closing upon receipt of a sample in said chamber, an upper kclosed chamber, a frangible tube disposed between said `munication with said conduit, a movable safety valve housing positioned above said swab cup, a normally closed ball check valve in said valve housing, said last-named valve opening on the imposition of a predetermined pressure thereagainst, a shoulder in said main housing ad v jacent the juncture of said uid conduit and said third chamber, the lower end of said valve housing seating on said shoulder to form a normally closed by-pass valve, a rst port in said main housing between said upper chamber and said swab cup, a second port in said main housing communicating with said third chamber, a third port in said valve housing abovevsaid ball check valve,

, a slidable rod extending upwardly into said fluid conduit and Vdownwardly into said upper chamber above said piston, a foot at the upper end of said rod and contact- Y 'ing the lower end of said valve housing and providing apertures between said foot and the lower end of said valve housing and placing the lower end of said valve housing in communication with said fluid conduit, stops o n said rod limiting upward and downward movement. thereof, said rod being actuated through contact'thereof 1I. bynsaidpiston to move said `valve housing upward and open saidy by-pass Valve, establishing fluid communication befween'said third chamber and said fluid conduit and permitting -eirculation of fluid through said second port, said thirdfchamber, said fluid conduit and said rst port, a slidable shaft connected to the upper end of said valve housing and extending exteriorly of said housingrfor liftingzsaid device, an explosive charge Vmounted adjacent said vfrangible tube, time-controlled means for exploding said `charge at a predetermined time whereby Huid and bit cuttings from a Well formation pass through said springbiased *valve andsaid lower chamber into said upper chamber to displace said traveling piston upwardly-into contact with said rod for actuation of` said by-pass valve.,

6. A device as defined in claim 5, wherein said second l5 port is disposed adjacent the lower end of said third chamber, and including a fourth port in said main housing communicating with said third chamber, said fourth port beingy disposed above said second vport and adjacent said Y third port.

7l A formation sampler tool adaptedto be inserted into a drill pipe, which comprises a chamber, a passageway at the lower end of` said chamber, a closure for said chamber in said passageway, means for rupturing said closure, a first valve in said passageway below said closure, said valve permitting ow of fluid and sample cutting from a zone exteriorly of said tool into said passageway, means for actuating said valve, packing means connected to the outer wall of said sampler toolk and adapted to contact said drill pipe to prevent circulation between said tool and said drill pipe, an inlet port and an outlet port in said tool disposed on opposite sides of said packing means, a by-pass lin said toot communicating with said ports and permitting circulation through a portion of said tool from one side of said packing means to the other side thereof, a second valve in said by-p-ass, and means in said chamber and connected -to said second valve to actuate said second Valve in response to introduction of said sample of bit cuttings into said chamber,

8. A formation sampler tool adapted to be inserted into a drill pipe, which comprises a chamber, a passageway at the lower end of said chamber and communicating with said chamber, a frangible closure in said passageway and separating it from said chamber, means for frac-` turing said frangible closure at a predetermined time, a check valve in said passageway permitting fluid flow only from the exterior of said tool into said passageway when the external pressure is greater than that in said passageway, a freely sliding piston in said chamber, packing means connected tothe outer wall of said sampler tool and adapted to expand into Contact with said drill pipe to prevent circulation between said tool and said drill pipe, an inlet port and an outlet port in said tool disposed on `opposite sides of said packing means, a by-pass in said tool communicating with said ports and permitting circulation through a portion of said tool from one side Y of said packing means tothe other side thereof,` a second d valve in said by-pass, means connected to said piston and said second vvalve and operable in response to movement t of said piston for actuating said second valve, and a third ValYe in said by-pass operating independently of `said second lvalve and permitting circulation through said portion of said sampler tool when said second valve is closed,` and means for opening said third valve at a`predeterrr1ined.,65 pressure. Y i v 9. In combination, a drillstring `including a drill bit connected to said drill, string, said drill bit having v`cirf' culation 4ports therein,v -a sampler, tool disposedin said.'r drill Vstr-ing adjacent said drill bit andin communicationfqg withfsaid circulation ports, said sampler tool comprising, a chamber, a passageway to said chamber, a closurezv'for said.chamberw in said, passageway, means s forrupturing t said: closureat ,a predetermined ,tirne,ta checkA `valve in Sauvageau-permitting @uid V1l wv., i1lr in@ Said pas '75 `ing a sample, receiving chamber in said sampler, a packer l said packer to the other side of said packer, a valve in said Y 4by-pass conduit, a rod connected to said valve and adapted` 3tool and opening said by-pass valve, a fluid communicating passageway to said chamber and adapted to receive y ,sampler through said passageway into said chamber, and.; y

l gage said drill string, said packer closing communication@ sageway when the external pressure is greater than that ,j

in said passageway, a freely sliding piston in said cham-I l ber,fpacking means connected to the vouter wall of said f sampler tool and in contact with said drill string to pre;l i ventcirculation between said tool and said drill string and 1.;

past said tool, `ankinlet port and annoutlet port` in saidtoolddisposedon opposite sides of said packing means, a l

by-pass in said tool communicating with said ports and permitting circulation through said drill string and ak pori tion of said tool from one side of said packing means to Y the other side thereof, a second lValve in said by-pass, and?,

means connected to saidpiston and to said second valve,Y and operable in response to movement of said piston for v actuating said second valve.

10. A bit cuttings retriever for oil wells, said dev icew being adapted to betinserted` into a drill vpipe, whichl corn-` prises a main `housing including therein a closed chamber, means associated with said chamberfor introducing' a sample of bit cuttings into said chamber and maintaining said sample therein, packing means disposed about said,- housing above said closed chamber, said packing means preventing circulation between said device and said drill' f'pipe, a by-pass conduit in said mainrhousing, a first port p in said main housing between said packing means and l said closed chamber, a movable valve housing within said main housing and positioned above said packing means, a pressure valve in said valve housing normally closed and adapted to open on the imposition of a predetermined pressure, the lower end of said valve housing communicating with said by-pass conduit, a second port in said valve housing above said pressure valve, a shoulder .in said main housing, the lower endl of said valvehousing cooperating with said shoulder to form a normally closed by-pass valve, a third port in said main housing above said by-pass valve, and means in said chamber and operable in response to introduction of a formation sample into said chamber to move said valve housing upward and open said by-pass valve and permit circulation of fluid through said first and third ports and said by-pass conduit past said packing means.

ll. A sampler adapted to be introduced into a drill`v string including a drill pipe and a drill bit containing circulating ports connected to one end of the drill pipe, for positioning said sampler adjacent said drill bit, comprismounted externally of said sampler and adapted to en-v gage said drill string, said packer closing communication between said ports and the drill string above said sampler, a duid by-pass conduit in said sampler from one side of to open said valve on upward movement of said rod, said rod having a spear head at its upper end adapted to re- Y ceive an overshot grapple for simultaneously lifting said fluid passing through said ports when said sampler is in position adjacent said bit, a second valve in said passageway, permitting flow of fluid from the exterior of said means associated with said second valve of uid through said passageway sampler in the opposite direction.

12. A sampler adapted to be introduced into a drill` .string including a drill pipe and a drill bit containing cir-, v 4zculating ports connected to one end of the drill pipe, for.Y positioning rsaid sampler adjacent said drill bit, compris- -V inga sample, Vreceiving chamberin said sampler, a packer. mounted externally of said sampler and adapted to en-,

to preventflow and exteriorly of said L.,

between said ports andthe'drill string above said sampler,L

a fluid by-pass conduit in said sampler from one side of. saidpacker'to the .other side of said packer, a Valve insaid l.. bypassconduit', means operable in response to receipt-t`of`-tl a sample of bit cuttings` in said chamber to open sa'i d,.;Y

valve, a uid communicating passageway to said chamber and adapted to receive uid passing through said ports when said sampler is in position adjacent said bit, a valve in said passageway, said valve opening on the imposition of external pressure greater than the pressure in said passageway, to permit flow of duid through said passageway into said chamber from a zone exteriorly of said ',sampler, and to close said valve to prevent ow of duid through said passageway and exteriorly of said sampler in the opposite direction.

13. A sampler adapted to be introduced into a drill string including a drill pipe and a drill bit containing circulating ports connected to one end of the drill pipe, and positioning said sampler adjacent said drill bit, comprising a sample receiving chamber in said sampler, a tluid communicating passageway to said chamber and adapted to receive fluidppassing through said ports when said sampler is in position adjacent said bit, a valve in said passageway, permitting ow of lluid from the exterior of said sampler through said passageway into said chamber, and means associated with said valve to prevent flow of fluid through said passageway and exteriorly of said sampler in the opposite direction, a closure member in said passageway, means to rupture said closure member on passage of a predetermined time interval to permit passage of fluid into said chamber, and means connected to the upper portion of said sampler and adapted to receive an overshot grapple for lifting said sampler to the well surface.

14. A sampler adapted to be introduced into a drill string including a drill pipe and a drill bit containing circulating ports connected to one end of the drill pipe, and positioning said sampler adjacent said drill bit, comprising a sample, receiving chamber in said sampler, a packer lmounted on the outer wall of said sampler and adapted to engage said drill string, said packer closing communication between the said ports and the drill string above said sampler, a uid communicating passageway to said chamber and adapted to receive fluid passing through said ports when said sampler is in position adjacent said bit, a valve in said passageway permitting ow of fluid from the exterior of said sampler through said passageway into said chamber, and means associated with said valve to prevent flow of uid through said passageway and exteriorly of said sampler in the opposite direction, a closure member in said passageway, means to rupture said closure member upon passage of a predetermined time interval, a fluid by-pass conduit from one side of said packer to the other side of said packer, a valve in said by-pass conduit, a traveling piston in said chamber and a lift rod in said chamber between said piston and said last mentioned valve, said rod opening said last named valve on a predetermined travel of said piston in response to passage of uid into said chamber.

15. A sampler adapted to be introduced into a drill string including a drill pipe and a drill bit containing circulating ports connected to one end of the drill pipe, and positioning said sampler adjacent said drill bit, comprising a sample receiving chamber in said sampler, a packer mounted on the outer wall of said sampler and adapted to engage said drill string, said packer closing communication between the said ports and the drill string above said sampler, a fluid communicating passageway to said chamber and adapted to receive uid passing through said ports when said sampler is in position adjacent said bit, a valve in said passageway permitting tlow of uid from the exterior of said sampler through said passageway into said chamber, and means associated with said valve to prevent ow of uid through said passageway and exteriorly of said sampler in the opposite direction, a closure member in said passageway, and means to rupture said closure member upon passage of a predetermined time interval, said closure member being frangible, and said means to rupture said closure including an explosive charge.

16. A sampler adapted to be introduced into a drill string including a drill pipe and a drill bit containing circulating ports connected to one end of the drill pipe, and positioning said sampler adjacent said drill bit, comprising a sample receiving chamber in said sampler, a packer mounted on the outer wall of said sampler and adapted to engage said drill string, said packer closing communication between the said ports and the drill string above said sampler, a iiuid communicating passageway to said chamber and adapted to receive tluid passing through said ports when said sampler is in position adjacent said bit, a valve in said passageway permitting flow of fluid from the exterior of said sampler through said passageway into said chamber, and means associated with said valve to prevent flow of fluid through said passageway and exteriorly of said sampler in the opposite direction, a closure member in said passageway, means to rupture said closure member upon passage of a predetermined time interval, a fluid by-pass conduit from one side of said packer to the other side of said packer, a valve in said lby-pass conduit, said closure member being frangible and said means to rupture said closure member including an explosive charge, and means in said chamber connected lto said last named valve and operable in response to rupture of said closure member and receipt of iluid in said chamber to actuate said last named valve.

17. A sampler adapted to be introduced into a drill string including a drill pipe and a drill bit containing circulating ports connected to one end of the drill pipe, and positioning said sampler adjacent said drill bit, comprising a sample receiving chamber in said sampler, a packer mounted on the outer wall of said sampler and adapted to engage said drill string, said packer closing communication between the said ports and the drill string above said sampler, a fluid communicating passageway to said chamber and adapted to receive fluid passing through said ports when said sampler is in position adjacent said bit, a valve in said passageway permitting flow of lluid from the exterior of said sampler through said passageway into said chamber, and means associated with said valve to prevent ow of lluid through said passageway and exteriorly of said sampler in the opposite direction, a closure member in said passageway, means to rupture said closure member upon passage of a predetermined time interval, a uid by-pass conduit from one side of said packer to the other side of said packer, a port in said sampler on each side of said packer and communicating with said bypass conduit, a check valve operable at a predetermined pressure in said by-pass conduit to permit uid ilow through said conduit and said last named ports, a second valve in said by-pass conduit operating independently of said check valve, and a rod connected to said second valve and adapted to open said second valve to permit passage of uid through said bypass conduit and said last named ports on upward movement of said rod, said rod having a spear head at its upper end adapted to receive an overshot grapple for simultaneously lifting said tool and actuating said rod to open said second valve.

References Cited in the tile of this patent UNITED STATES PATENTS 1,522,197 Macready Jan. 6, 1925 1,697,249 Macready Ian. 1, 1929 2,176,240 Bandy Oct. `17, 1939 2,201,447 Mullins May 21, 1940 2,214,551 Edwards Sept. l0, 1940 2,493,962 Gray Jan. 10, 1950 2,497,185 Reistle Feb. 14, 1950 2,577,210 Ruska Dec. 4, 1951 2,623,733 Sewell Dec. 30, 1952 2,661,803 Ramsey Dec. 8, 1953 2,674,439 Chambers Apr. 6, ,1954 2,681,795 Gregory June 22, 1954