US2103475A - Apparatus for taking fluid samples - Google Patents

Description

Dec. 28, 1937.

B. E. LlNpsLY APPARATUS FOR TAKING FLUID SAMPLES Filed May 28, 1935 2 Sheets-Sheet l ...if 4 A INVENTOR 5e T/2d:

ATTo'FgNEY Dec. 28, 1937. B. E. LINDsLY APPARATUS FOR TAKING FLUID SAMPLES 2 Sheets-'Sheet 2 Filed May 28, y1935 15 vll 75 ...Illini fr INVENTQR 9e/7 E. L//ms ATTORNEY pool.

Patented Dec. 28, 1937 f c UNITED STATES PATENT OFFICE 11 claims.

'I'his invention relates to a method and apparatus for obtaining samples from which physical and chemical characteristics of a uid are ascertained as th'e fluid exists in a natural reservoir. For example, it is desirable to possess data regarding condition of oil containedin an oil producing, formation, such as the quantity of gas' liberated from-solution upon diminution of pressure, the relative volumetric proportions of gas to oil at various pressures throughout the length of ow stringinfaI vwell ydrilled into the formation, and other similar data wherewith it is possible to predict physical changes that oil and gas mixtures may undergo throughout the life of the oil The possession of such information also makesit possible to more efficiently design well flowing equipment.

Heretofore ithas been diilicult to obtain samples which actually represent subsurface mixtures of oil and gas for the reason that such samples are taken at different pressures and temperatures than those actually existing in the producing formation. Also, the oil contained in such samplesl has been intermingled with extraneous gasfi. e.', gas which either was in solution originally or was liberated from solution at some higher pressure and later became mixed with the original undis solvedgas. s

It is obvious that such samples might have their gas content either increased or decreased from than the oil originally contained. On the .other hand, if the oil in the original reservoir were completely saturated with gas, reduction of pressure and change in temperature at the place where the sample was taken would result in gas liberation so that the sample contains less gas per unit volume of oil than was originally contained inan equal volume in the reservoir.

It is, therefore, the principal object of the present invention to provide for taking samples of the uid directly at the bcttom of the well and at substantially the temperature and pressure conditions carried within the producing formation.

In accomplishing this and other objects of the invention, ashereinafter pointed out, I have provided improved details of structure, the preferred (ol. 16s-19) forms of which are illustrated in the accompanying drawings, wherein:

Fig. 1 is a vertical section through a well in which is illustrated a sampling apparatus, embodying the features of the present invention.

Fig. 2 is a similar but enlarged view showing v the gsampling apparatus in vertical section and showing the trapping valves in open position to admit oil to the collecting chamber of the apparatus. l0

Fig.'3 is a similar view but showing the valves in closed position to trap a sample of the oil in the collection chamber.

Fig. 4 is a vertical section through the apparatus in inverted position and equipped with a 16 laboratory head wherethrough the sample is removed to a testing bomb.

Fig. 5 is an enlarged section through the head of the apparatus particularly illustrating the method of admitting the pressure fluid and tim- 20 ing outlet of the fluid to control operation of the Aupper trapping valve.

Fig. 6 is ahorizontal section on the line 6 6,

Fig. 5.

Fig. '7 is a horizontal section on the line 1-'|, 25 Fig. 2.

Fig. 8 is a horizontal section through the laboratory head on the line 8 8, Fig. 4.

Fig..9 is a detail fragmentary section of the container barrel particularly illustrating the lower 30 trapping valve and its seat.

Fig. 10 is a detail perspective view of thegspider used in unseating the upper valve when the sample is to be transferred to the testing bomb.

Fig. 11 is a vertical section through a well hole 35 similar to Fig. 2 illustrating a sectional view of a 4modified form of the invention. Referring more in detail to the drawings: I designates a sampling device that is lowered through a well hole 2 by means of a cable 3 to a 40 point adjacentthe bottom of the well for taking a sample of the fluid owing from the oil producing strata into the well hole. The sampling device includes a tubular section l of suitable diameter to be freely lowered through the well 4,5 hole or a flow stream, and of sumcient length to provide a collection chamber 5 having suiiicient capacity to contain asample of desired quantity. Fixed to the lower end of the tubular section is a nipple Shaving threaded ends 'l and 8 for 50 respectively engaging'the internal threads 9 in the lower end of the tube and internal threads i0 of a coupling Il having its lower end terminating in depending ears l2 and I3 located at opposite sides of a fluid inlet slot Il. The/ 56 ears I2 and I3 are provided with apertures I5 and I6 through which a bolt I1 is passed for connecting a temperature and pressure recording device indicated at' I8, Fig. 1. The device I9 may be any one of a number of conventional devices now-on the market and specically forms no part of the present invention.

The well iluid enters the coupling II through the slot I4 and is apt to carry with it quantities of sand or other material that might tend to keep the valves from seating. To prevent entrance of sand with the oil into the flow channel I9 of the nipple 6, a plurality of spaced screens 20 are inserted in the coupling II below the threaded end when the valve is closed by gravity as presently described.

The valve 24 remains seated by reason of gravity and opens in response to flow of fluid through the ports 21 of the spider to admit the fluid into the collection chamber r5. To limit upward movement of the valve, the lower end of the stem carries a stop 28 that engages against the lower face of the spider.

In order to seal the threaded connections of the nipple with the lower end of the tubular section and coupling Il, the nipple is provided with an annular collar 29 to form upper and lower annular shoulders 3U and 3I to seat gasket rings 32 and 33 that engage against the ends of the tubing section and coupling respectively.

A similar nipple 34 is threaded into the upper end of the tubing section and carries a spider 35 and valve seating ring 36 on its lower end identical to the spider and seating ring carried by the lower nipple to form a guide for a valve rod 31 and a seat for a valve 38 carried on the lower end of the rod and whereby flow of luid from the' collection chamber to the check chamber is stopped to retain a sample of the uid in the col-l ed on the upper end of the nipple 34, as best illustrated in Fig. 2. The upper end of the guide section carries a head 40 having a reduced neck 4I on its lower end that is threaded into the upper end of the guide section. Fixed. to the .upper end of the head is a loop 43 having an eye to which the cable 3 is connected.

Located within the lower end of the guide section is a horizontal partition 44 spaced from the upper end of the nipple 34 to form the bottom of guide and check chambers 45 and 6I that prevents sudden closing of the valve 38 incidental /to flow of well fluid through the upper end oi' the tubular section to a plurality of outlet ports 43 that are formed in the guide section at a point below the partition 44, the total area of the outlet ports 48 being such as to permit free flow of oil there-through to facilitate the complete purging of collection chamber 5, during this process of bobbing later described.

With the construction thus far described, oil ows through the inlet slot I4, screen 20, through the ports of the spider 2l, past the lower valve into the collection chamber and out of the collection chamber past the valve 38 through the ports of the spider 35 into the check chamber and out through the ports 48 while the device is being lowered into the well.

Upon suspending the lowering operation of the device, the lower valve will seatfunder gravity but means must be provided for seating the upper valve tovtrap a sample of uid within the collection` chamber.

In the preferred form of the invention, this is accomplished by means of a coil spring 49 housed within the guide section and having one end bearing against the partition 44 and its opposite end against the follower plate 5U of a cup-shapedl piston 5I under response toflow of a pressure fluid 52, that has been injected into the guide section through the head `40, as now to be described.

Threaded into a recess 53 extending radially within the head 49 is a check fitting 54 having a port 55 normally closed by a back check valve 56 that is normally retained seated by means of a spring 51. The outer end 58 of the fitting is shapedto accommodate a conventional type high pressure grease gun for delivering grease or other pressure medium past the valve and through a channel 59v which conveys the iiuid through a nozzle 60 into the chamber 6I that is formed between the head and the piston 5I to force the,

piston downwardly against pressure of the spring 49 which causes the valve stem 31 to unseat the valve 38. l

'I'he head 43 is also provided with anoutlet channel 62 which communicates with a restricted port 63 ina plug 64 threaded into a recess 65 in the side of the head 40 opposite the inlet 50 and having an enlarged outer'portion adapted to receive the head 66 of a needle valve 61 having a tapered end 68 adapted to fit the seat 69 at the outer end of port 63 to prevent escape of grease from the check valve when the needle valve is in place.

The inlet of the channel 62 is covered by a screen 10 that is carried by a plug II threaded into the recess 12 of the head and having a bore communicating with the channel, the purpose of the screen 10 being to prevent material from the chamber from'entering the channel that might tend to clog the outlet port 63, through which the grease is discharged under the propelling nuence of the piston actuated by the sp/ring 49 when the needle valve 61 is removed. Since the port 63 is of fixed size, the rate of grease flow is constant and provides for timing closure of the valve 33.

Inorder to protect the inlet tting and port 63, the upper portion of the head is of reduced diameter to loosely mount a .guard ring 14 having its lower end attached to a shoulder 15, the inner diameter of the ring being such as to provide ample space between the ring and the reduced portion of the head 40 for the outlet of grease when the needle valve 61 has been,re' moved.

In using an apparatus constructed and assembled as described, the pressure and temperature recording device is run into the well to determine the actual pressure and temperature conditions and temperature is calculated the size of the port 63 to give thedesired time closing of the upper valve. A plug .84 having the required orice is then screwed into the recess, after which the needle'valve 8.1 is threaded into the plug to close the port 88 while grease is being injected through the inlet fitting into the chamber 8I.

The amount ofgrease injected is preferably suchas to effect compression oi' the spring about two and one-half inches; the amount ofvgrease admitted. of course, depending upon its viscosityV and the depth of the well or the point at which the sample is to be taken, the idea being that e grease flow through the port 88 will provide am le time for the device to be run into the well, ilushed of well fluid and a sample of oil admitted to the collection chamber before sumcient amount of been extruded to permit closure of the ,limer-valve;

In usual practice, it requires about thirty-four minutes at a temperature of 132 F. to expel grease from the chamber 8l and, therefore, the sampling operation is planned so that the desired sample will be-in the collection chamber within thirty-four minutes after removal of the needle valve. Usually, however, the time required to close the upper` valve is greater than the calculated thiriy-four minutes for the reason that it takes at least twenty minutes for the sampling device and the oil in the cylinder to approximately assume the bottom hole temperatures.. The grease, therefore, remains in viscous Vcondition for a longer period and the closing period of the valve is longer than that calculated.

After` the grease has been injected, the needle valve is inserted to prevent extrusion of the grease under the action of the spring 49. The temperature and pressure recording device I8.is then secured to the bolt I1 by means of a wire 'I8 as 'shown in Fig. 1, or preferablyr by inserting bolt I1 through the hole in the head of device I8. which has previously been drilled and shaped to i'lt between ears I2 and I3, and the lowering cable is attached to theeye of the loop 43.

As soon as the device is ready to be lowered into the well. the ,needle valve for closing the orifice 63 is removed and the-guard 14 positioned over the reduced portion of head I4l) to prevent entrance of foreign matter that might tend to clog the outletof the orifice. 'I'he devicev is then lowered into the well to the bottom ther'eoflor to the point at which the sample is to be taken.

During lowering of the device, the liquid standing in the well enters through the slot I4, lifting the lower valve and moving past the unper valve for ilow out through the ports 48 -so thatthere is a 'constant movement of liquid therethrough. During tle lowering of the device, the spring 49 is gradually expanded to extrude the grease but at the time vthe device has reached the botptom of the hole,- however, there is `still suilicent grease remaining to hold the valve in open position for a suiiicient length of time to obtain an actual sample within the collection chamber.

In order to overcome uncertainties of obtaining a true sample, it is good practice to allow the sampling device to remain in the bottom of the well a suiilcient length of time to permitit to take on the temperature vcf the iiuid issuing from e the formation.

When the device reaches the bottom of the well it is raised and lowered a number of times to purgev the collection chamber of well uid received thereinto during lowering ofthe device through me wnue bobbing the sampling device. the down strokeshould be made as rapidly as possible so that the impact on the lower the upper valve is closed, the device is withdrawn l from the well.

After lremoval of the device from the well the coupling II is4 removed from the nipple 6 and the spider (Fig. ll0) is inserted in the open end of the nipple, as shown in Fig. 4. The spider includes a cylindrical body portion 18 having depending legs 19 and 88 spaced apart tostraddle the stem of the valve 24, the legs 19 and 88 being of suitable dimensionsto pass through theA ports of the spider and engage against the face of the valve.

A laboratory head 8| is then screwed onto the nipple so that an end 82 thereof sealingly engages Ywith the gasket on the nipple. The laboratory head is lprovided with a central bore 83 threaded at its lower end to mount a screw 84 having a cone-shaped point on its lower end adapted to seat in a cone-shaped recess 85 on the body portionv of the spider. The opposite end of the bore is formed to receive a suitable pack'ng ring 86 communicating at their inner ends with the interior of the nipple and at their outer ends respectively with a source of fluid pressure medium. such as mercury, and with a testing bomb through tubings 9| and 92. All of the air in head 8|, channels 88 and 89, bomb 90 and connection tubes 9| and 92, is completely displaced by filling these spaces with mercury, or other suitable medium. Y

It is thus apparent that when the valve 24 is opened, communication is established with the interior of the collection chamber and the interior of the testing bomb and with the source of fluid pressure medium. 'I'he mercury or other suitable liquid which will not mix with the sample of well fluid is then pumped under the required,.pressure.through...the channel 88 into the collection chamber to displace the sample therefrom, which flows out through the channel 89, tubing. 92 and by proper manipulation of valves Idislplaces the mercury which had previously been placed in the testing bomb.

When the testing bomb is being filled, the mercury and the bomb are maintained at an equal or somewhat higher pressure than the pressure determined by the measuring device I8. When oil has displaced all of the mercury from the bomb, valves 93, 93a, and 93h are then closed to retain .the remaining oil in chamber -5 and to en'- trap the sample of 'oil in the testing bomb. The testing bomb is then disconnected from the laboratory head and the sample contained therein may, by simple manipulation of valves, and subjection to a constant temperature bath, be brought to the same pressure and temperatureiconditions and thereby become 'identical in chemical and physical characteristics as when in the producing formation.

The sample' is then .tested to determine th physical and chemical characteristics of the oil.4

In the modified form of the device (Fig. 11)

-the check chamber within the guide section 96 corresponding to guide section 39 of the preferred form of the device. Fixed to and extending upwardly from the dash pot is a rod 91 which terminates below a packing nut 98 that divides the check chamber into upper and lower portions99 and |00, the lower of which is provided with vent ports through which fluid in the check charnber may escape to the well. The ,upper endof the rod 91 carries a collar |03 adapted for supporting a trip rod |04 whichis slidable in packing nut 98 and provided at its upper end with a collar |05 forming a seat |06 for the Varm |01 of a bell crank lever |08. Bell crank |08 is pivotally mounted on a bracket |09 attached to the inner face of the guide section within the upper portion of the check chamber and has a second arm ||0 extending substantially horizontally within the upper portions of the check chamber. Surrounding rod 91 within the lower portion |0| of the check chamber and bearing at its lower end against a plug in said chamber and at its upper end against the collar |03 on said rod is an expansion spring I2 adapted to urge the rod upwardly and hold the arm |01 of the bell crank lever to its seat on collar |05. Spring ||2 is held compressed and the valve 38 open to permit passage of well fluid through the collection and check chambers to exit through the outlet ports in the guide section. When the collection chamber has been purged preparatory to receiving a sample, the stop valve 38 is moved to its seat to close the collectionchamber by unseating of the bell crank lever from its engagement with collar |05 so that the spring ||2 may lift the rod 9T and stem 31 of valve 38 through thrust of a rod H4, slidably mounted in a channel ||5 in a head member ||3 carried by the guide section, under impact of a go-devil ||6 which is slidably mounted on the cable whereby the device is suspended in the well.

What I claim and desire to secure by Letters Patent is:

1. Apparatus for taking samples of fluid from a Well including a collection chamber having inlet and outlet ports,l a trap valve for preventing back flow from said chamber through the port, a stop -valve controlling outlet of fluid from the chamber through the outlet port, means for closing the stop valve, and means for retarding closing movement of the stop valve,

2. Apparatus for taking samples of uid from a well including a collection chamber having inlet and outlet ports,` a trap valve for preventing back ow from said chamber through the inlet port, a stop valve controlling flow of iiuid through the chamber and outlet port, means for closing the stop valve, and means for confining a body of' fluid in restraining relation to said closing means to retain the stop valve open, including a 'bleeding port through which said uid may escape in restricted flow to permit closing of the stop valve.

3. Apparatus for taking samples of iiuid from a well including a collection chamber having inlet and outlet ports, a back ch'eck valve for the inlet port, a stop valve for the outlet port, means yieldingly urging the stop valve to closed position, meansfor closing the valve, means vfor ef- A fecting application of pressure to Said closing means to resist closing of the valve, and means foi' releasing the pressuremeans to'permitl closing of the valve.

4. Apparatus for taking samples of fluid from a well including a collection chamber and having inlet and outlet ports, a back check valve for the inlet port, a stop valve for the outlet port, means for closing the stop valve, and means for conning fluid pressure medium in retarding vrrelationy to said closing means including an outlet for release of said pressure medium in restricted flow to permit slow closing of the valve.

5. Apparatus for taking samples of fluid from a well including a chamber having inlet andoutlet ports, a back check valve for the inlet port, a

.stop valve for the outlet port, a fluid check chamber, yielding means urging the stop valve to ,closed position responsive to pressure of fluid in said chamber.

6. A sampling device of the character described including a tubular body member enclosing a sample fluid collecting chamber provided with inlet and outlet ports and a check chamber connected with the collecting chamber, a check valve for said inlet port, a stop valve controlling flow of uid between said chambers, a piston in the check chamber, means connecting the piston with said stop valve, a spring for moving the piston in one direction, means for supplying iiuid pressure medium tothe check chamber to shift the piston against the tension of said spring, andan orifice member for permitting release of 'said vfluid pressure medium toeffect slow closing movement of the stop valve under tension of said spring. l

'7. A sampling device of the character described including a sample fluid collecting chamber having inlet and outlet ports and a check chamber connected with the collecting chamber through said outlet chamber, a check valve for the inlet port, a stop valve for the outlet port, a piston in the check chamber, a rod connecting the piston with the stop valve, a spring urging the stop valve to closed position, and means for introducing pressure medium .into said check chamber to act against the piston for retaining the stop valve in open position against the tension of said spring, the check chamber having restricted outlet for releasing pressure medium from the check chamber in restricted ilow to permit closing of the stop. valve by said spring.

8. In apparatus for taking samples of fluid l from a well, a hollow barrel including separate collecting and-check ,chambers and vent openings between the chambers, inlet and outlet ports permittingilow through the collecting chamber to said vent ports, a back check'valve for said inlet port, a stop valve for said outlet port responsve to pressure of fluid in the check chamber for opening the outlet port, means for bleeding the check chamber of fluid, and yielding means responsive to pressure of said fluid to permit the stop valve to open and for gradually seating the stop valve against diminishing pressure of said uid.

9. Apparatus for taking samples of fluid from a Well including a collecting chamber having inlet and outlet ports permitting flushing flow of well fluid through said chamber, a check valve for the inlet port, a stop valve for the outlet port, a piston in the check chamber connected piston in one direction in response to supply of pressure uid to the check chamber to unseat the stop valve, means for releasing 4pressure medium from the cl eck member to permit movement of the piston inthe opposite direction to close the valve, and yielding means resisting movement of the piston to open-the valve and urging the piston to close the valve.

10. Apparatus for taking a sample of iluid from a. well including a. collecting chamber having a port for admitting fluid from the well and an outlet port, a check chamber having a bleeding port and an intermediate vent chamber adapted to receive well iluid through said outlet port and having a vent opening, a check valve for s'aid inlet port, a valve for said outlet port, a piston in the check chamber connected with the outlet valve,

and a spring urging the piston to close the outlet valve against diminishing volume of pressure fluid escaping from the check chamber through said bleeding port.

11. Apparatus for taking a sample of iiuid from a well including a collecting chamber having inlet and outlet ports, a check chamber having a bleeding port and an intermediate vent chamber connected with the collecting chamber through said outlet port and having a vent opening, a back check valve for said outlet port. a piston in the check chamber, a rod connecting the piston and outlet valve, and a spring engaging the piston, yieldable under pressure of uid supplied to the check chamber to permit the outlet valve to open and expansible under diminishing pressure of uid exhausting from said chamber to gradually close the valve.

BEN E. LINDSLY.

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