US 3459263 A
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Description (OCR text may contain errors)
Aug. 5, 1969 l J. A. P. DRIVET 3,459,233
FLUID SAMPLING DEVICE med May 29, 1967 5e. 1 l Hs.
United States Patent O 3,459,263 FLUID SAMPLING DEVICE .lean Auguste Prosper Drivet, St.-Germainen-Laye, France, assigner to Societe Anonyme: Societe Auxiliaire des Producteurs de Petrole Flopetrol, Iaris, France Filed May 29, 196'7, Ser. No. 641,895 Claims priority, applicationFrance, June 9, 1966,
Im. Cl. soin 1/10 U.S. Cl. 166-165 10 Claims ABSTRACT F THE DISCLOSURE The study of oil fields requires a precise knowledge of the fluids contained in them. Where, in some cases, it is possible for a Well bottom sample to be reconstituted by re-combining those phases taken from the surface at the separator outlet during a well test, such technique necessitates important means. Moreover, where the well pressure is only slightly higher than the fluid bubble pressure, the only possibility of obtaining a readily utilizable sample is to take a sample from the Well bottom since the well is closed and has a very small output.
This accounts for sampling devices having also been made for taking fiuid samples from the bottom of a deep well.
One problem to be solved in the case of such a iiuidsampling device is the correct control of well bottom valves so as to admit the fluid to be sampled into a taking chamber and subsequently to close said chamber. Another problem is to close this chamber under such conditions that the sampling device remains closed when being lifted in the well irrespective of the ambient pressure conditions and that the contents of said chamber may be verified at ground surface and transferred to a bottle or any other transporting container. Known sampling devices have not, however, permitted this problem to be satisfactorily solved hitherto.
An object of the invention is to provide a sampling device adapted properly to achieve correct control of the valves in the required fashion `and to be kept closed when being lifted through the Well regardless of pressure conditions.
Another object of the invention is to provide a iiuidsampling device for deep wells adapted to be lowered into the well by means of a steel wire line and including a sampling chamber defined in the body of the device and delineated adjacent each end by a bore-forming seat through which an associated valve may be tightly slidden by engagement into it, both valves being positively interconnected by a control rod `and displaceable from an opened position, particularly for allowing the iiuid to be sampled to enter said chamber and a closed position through said seats, means urging said valves into said closed position, a triggering mechanism controlling the motion of said rod so as to close the valves, and a timer which sets the instant at which said triggering mechanism operates.
A further object of the invention is to arrange for the distance between the seats and the valves to be so calculated that one of the valves can be opened while the other valve is still closed, particularly when the sample is transferred to a new bottle or container situated on the ground surface. For obtaining this result, the distance between the valves carried by the control rod is preferably shorter than the distance between an end of the bore forming a seat and the end of the other seat-like bore which extends in the same direction axially of the sampling device. Thus one valve can be opened inwardly of the chamber while the other valve is still in the corresponding seat-like bore and in closed position.
Preferably the valves are held in closed position, irrespective of ambient pressure conditions, by one or several locking members for example of the snap-in type and/ or by a spring.
Yet another object of the invention, is to arrange for the valve-interconnecting rod to terminate at its free end in the form of a head or similarly outlined formation permitting axial coupling with a control device so as to provide, during transfer of the sample to the ground surface, an accurate control of said rod for a sequential positive opening of the two valves.
A still further object of the invention is to provide a sampling device in the body of which is defined a chamber so shaped adjacent each end as to permit an easy connection (for example by screwed parts) of those devices adapted to perform the transfer of the sample to the transporting container and to enable control of the valveinterconnecting rod to take place.
In a suitable constructional form, the triggering mechanism includes a dual screw element system one element of which is connected with a timer by which it is rotated while the other element is so urged (either naturally or artificially) when it is freed owing to the rotation of the first element in the unscrewing direction as to engage a percutor or hitting pin, a valve or an equivalent member capable of providing a communication for achieving displacement of a piston slidable in a cylinder and connected to the valve-interconnecting rod of the sampling device. Such a communication then displaces the piston responsive to a pressure differential and consequently the actuation of the valve-carrying rod and the closing of the valves in the medium to be sampled after a period of time which is set by the timer and the screw element system.
It will be understood that adjustment of the :screw element system permits an easy determination of the instant when the triggering action will take place.
With these and such other objects in view as will incidentally `appear hereafter, the invention comprises the novel construction and combination of parts as described in the accompanying diagrammatic exemplifying the same and forming a part of this disclosure.
FIG. l is an axial sectional view showing the triggering mechanism of this improved sampling device.
FIG. 2 is an axial sectional view of the body of the sampling device.
FIG. 3 is a view showing the body of the sampling device as inverted for the transfer of the sample to a transporting container.
The triggering mechanism `shown in FIG. 1 comprises a tubular element 1 constituting the body of this mechanism and closed lat its upper end by a plug 2 having a screw-threaded stem 3 adapted to receive an element permitting this mechanism to be connected to a steel wire line. Inside the body 1 is housed a timer 4 of the type commonly used in the oil-exploiting industry the operating period of which may vary from 3 to 180 hours. The drum shaft 5 of this timer 4 is connected to a screw 6 guided by a stationary collar bearing 7 and associated 3 with a tapped weight 8 having a guiding pin 9 cooperating with a longitudinal slot 10 formed in a sleeve 11 connected to the timer 4 and carrying the collar bearing 7 that guides the screw `6.
The purpose of the weight 8 is, as described hereafter, to engage by percussion or otherwise a hitting pin or percussor 12 adapted to perforate a diaphragm 13 so as to provide a communication through an axial passage 13a between the annular chamber 14 of the triggering mechanism and a cylinder 15 in which is received for sliding motion a piston 16 having its lower end connected with a coupling sleeve 17 provided with an innerly screw-threaded portion 18 and subjected to the pressure prevailing in the well owing to ports 19 formed at the lower end of the tubular element 1.
The sampling device shown by FIG. 2 comprises a tubular body 20 provided at its upper end with a sleeve 21 screwed into said tubular body 20 and having a bore 22 forming a seat and at its lower end `a sleeve 23 having likewise a bore 24 forming a seat. The sleeve 21 has an extension 23 fitted with a screw-thread 26 for connection with the triggering mechanism (FIG. 1). The sleeve 23 which is screwed into the tubular element 20 is connected with interposition of a sleeve 27 with an shoe 28 for-ming the lower end portion of the sampling device and having a recess 29 housing a filter 30. Between the sleeves 21 and 23 is provided inside the tubular element 20 a chamber 31. In each seat-forming bore 22 or 24 may be engaged by a fiuid tight sliding motion an associated valve 32 or 33. These two valves are positively interconnected by a control rod 34 terminating adjacent its free end by a screw-threaded stem 34a engageable into the sleeve 17 and near its opposite end by a head 35 connected to it by a stern of small diameter 36.
The distance between the valves 32, 33 carried by the control rod 34 is advantageously less than the distance between the seat-forming bore 22 of the end of the other bore 24 extending in the same direction with respect to the sampling device, whereby one 0f the valves can be opened while the other one is still closed.
The valves 32, 33 are preferably held in closed position (as represented in broken lines in FIG. 2) irrespective of the ambient pressure conditions by a coil spring 37 and a locking system comprising a leaf spring 38 having a finger 39 abuttable, when the valves 32, 33 are in closed position, against the upper face of the extension 25 of the sleeve 21.
The sampling operation takes place as follows:
When preparing the triggering mechanism for operation, care should be taken to engage the weight 8 only upon a length of the screw 6 corresponding to the period at the end of which triggering should occur. Thus assuming a timer to have an operating period equal to t (total number of revolutions of the arbor of the drum 5) care should be taken, where it .is desired to trigger the operation at a period equal to t/ 3, to engage the weight 8 only over a length equal to one third of the screw 6. The body of the sampling device is then coupled by means of the screw-threaded portion 26, with the triggering mechanism represented in FIG. 1, whereafter the operation of the several contrivances are correlated by engaging the sleeve 17 upon the screw-threaded portion 34a of the free end of rod 34 controlling the valves 32, 33, and the assembly thus made up is lowered .into the well by being suspended from a steel wire line. At this time the valves 32, 33 occupy the position represented in full lines on FIG. 2.
When the assembly has reached the sampling level, it is slowly raised and again lowered several times so as to fill up the sampling device with the fluid to be sampled which flows into the chamber 31 by passing through the filter 30. In proportion as time passes, the weight 8 goes down and when reaching the end of the screw 6 freely slides through the sleeve 11 and ultimately engages the percutor 12 which, when perforating the diaphragm 13, establishes a communication between the oil filled cylin- CFI der 15 and the chamber 14 in which a pressure nearly equal to atomspheric pressure prevails.
Due to the effect of the difference of pressures, the piston 16 is moved upwardly while actuating the rod 34 carrying the valves 32, 33 `and closing these in the medium to be sampled as represented in broken lines in FIG. 2.
The assembly of parts is then lifted to the ground surface, the shoe 28 is unscrewed and the body of the sampling device is separated from the tri gering mechanism. The -body of the sampling device is afterwards inverted (as shown in FIG. 3) and an upper transfer head 40 is adapted to the sleeve 27, said head having lingers 41 pivotally carried by an element 42 housed in said head and associated with a knurled nut 43. To the extension 25 of the sleeve 21 is also adapted a lower transfer head 44 having a gate valve 45. Conditioning of the assembly made up of the sampling device and transfer heads is effected by filling the hollow portions with mercury, using therefor the gate valves 45, 46 after having produced vacuum or more simply taken the precaution of not trapping air.
For appreciating the quality of the sample, it is necessary to open the valve 32 without opening the valve 33 so as to be able to inject through the lower transfer head 44 successive quantities of mercury for re-compressing the sample to the attainment of the bubble point.
Opening of the valve 32 is done by applying pressure through the lower transfer head 44 until the head of the stem 35 abuts the support of the fingers 41. A research for the bubble point is then effected.
When the sample has been recognized as being proper, it is necessary to compress the same before transferring it through the gate valve 46 (by resorting to usual methods as used in the oil trade) into a transporting bottle or container. Consequently the upper valve should be opened. This operation is done by screwing the knurled nut 43 on its screw. The latter shifts the carrier for the fingers 41 which move off the cone while permitting their retraction and are closed under the head 35. The stem 34 is then shifted and opens the valve 33. The two valves 32, 33 then occupy their initial position as shown in full lines in FIG. 2.
The opening of the valve 33 following that of the valve 32 is obtained in this instance by means of a transfer head that has been engaged from the top. However on some appliances this head can be also screwed from the bottom upon the sampling device. In this case, this device is not inverted and assumes a transfer position similar to the one that it occupies in the well.
Obviously the constructional details of the abovedescribed embodiment can be altered in the field of technical equivalencies without departing from the scope of the invention. Thus for example the lower valve may contain a needle valve held closed in sampling position. Following its lift up to the ground surface, when it is desired to determine the bubble point, the possibility exists of screwing upon the lower end of the sampling -device a transfer head permitting said needle valve to be opened from the exterior.
One may also envisage to replace the seats and valves assemblies as above described by a device in which the valves do not move out of their seat, ports provided in said valves permitting, depending upon the position of the valves with respect to them, either to open or to close the chamber.
What is claimed is:
1. A fluid-sampling device for deep wells adapted to be lowered into the well by means of a steel wire line and comprising a body Vdefining a sampling chamber having two ends, a bore-forming seat arranged adjacent each end of said chamber, a valve slidably mounted in each seat, said valves being shiftable between an opened position allowing penetration of the fluid to be sampled and a closed position in the seats, a rod interconnecting said valves, means for urging said valves to closed position, a triggering mechanism for controlling motion of said rod so as to close the valves, and a timer for setting the instant at which said mechanism operates.
2. A duid-sampling device according to claim 1 in which the distance between the valve is smaller than the distance from one end of the seat-forming bore to the other bore extending in the same direction axially of the device so that one valve may be opened while the other valve is still closed.
3. A Huid-sampling device according to claim 1 comprising locking means for holding the valves in closed position.
4. A fluid-sampling device according to claim 1 in which the valve-interconnecting rod has a free end including a head arranged adjacent said free end of the rod, an actuator adaptable upon the body of the sampling device, and coupling means in said actuator for cooperating with said head so as to perform a precise control of the rod for opening the valves when thesample is transferred from the device after it has ybeen lifted up to the ground surface.
5. A Huid-sampling device for deep Wells adapted to be lowered into an oil or like well by being suspended from a steel wireline, comprising a body dening a sampling chamber and having two ends, screw-threads at both ends of said body, screw-threaded parts engaged with them for delineating said chamber, seat-forming bores in said parts, valves slidably fitted in said bores and shiftable between an opened position and a closed position in the seats, a control rod interconnecting said valves, said rod having a screw-threaded end and a free end, elastic means urging said rod towards a valve-closing position, a triggering mehanism removably adapted upon said body, a screw-thread in said mechanism for coupling'it with the lirst end of the rod, said mechanism being operable to close the valves, and a timer mounted in said mechanism for setting the instant at which it operates.
6. A Huid-sampling device according to claim 5 comprising locking means associated with the rod for holding the valves in closed position.
7. A huid-sampling device according to claim 5 in which the distance between the valves on the rod is larger than the distance between the mutually confronted ends of the screw-threaded parts but smaller than the distance from one end of one of these parts to the end of the other similarly extending part axially of the body.
8. A fluid-sampling device according to claim 5 cornprising a head at the free end of the rod, an actuator removably adaptable to the body, and coupling means shiftable by said actuator and engageable over said head for shifting said rod and opening the valves.
9. A fluid samping device according to claim S comprising a shoe removably adaptable to the device body, a bore in said shoe communicating with the bore in the adjacent screw-threaded part, and a filter in the bore of the shoe.
10. A Huid-sampling device according to claim 5 in which the timer includes a rotary drum, and the triggering mechanism comprises a screw-threaded stemI conwith said drum, a weight screwed upon said stem, a guiding sleeve, said weight being slidable in said sleeve, means for angularly locking said weight, a valve in said sleeve adjacent one of its ends for actuation by said weight, a cylinder, said valve communicating with said cylinder, a piston slidable through said cylinder, a coupling member on said piston, and means on said stem for cooperating with said coupling member for interconnecting said stem and said piston.
References Cited UNITED STATES PATENTS 2,298,627 lO/ 1942 Proudman et al 73425.4 2,342,367 2/1944 Pryor 166-165 2,577,210 12/1951 -Ruska 73-425.4 X 2,613,848 10/1952 Wood 73-425.4 X 2,625,226 1/1953 Wofford 73-425.4 X 2,728,397 12/1955 Ruska 166--162 X 2,870,844 1/1959 Barnes 166-165 DAVID H. BROWN, Primary Examiner U.S. Cl. XR. 73-425